Automatically-locking vacuum syringe, and associated system and method

Abstract

To provide an automatically-locking vacuum syringe, and an associated system and method.SOLUTION: Automatically-locking syringes are disclosed herein. A syringe in accordance with embodiments of the present technology can include (i) a barrel, (ii) a plunger slidably positioned within the barrel, and (iii) a lock plate coupled to the barrel. The plunger also extends through an opening in the lock plate, and a biasing member is configured to bias the lock plate to a locking position. When the plunger is moved from a depressed position to a withdrawn position, the lock feature engages the lock plate to drive the lock plate away from the locking position to thereby permit the lock feature to pass through the opening in the lock plate.SELECTED DRAWING: Figure 1B

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 061,902, filed August 6, 2020, and entitled "AUTOMATICALLY-LOCKING VACUUM SYRINGES, AND ASSOCIATED SYSTEMS AND METHODS," which is incorporated herein by reference in its entirety.

[0002] FIELD OF THE INVENTION The present technology relates generally to systems, methods, and devices for the endovascular treatment of emboli and / or thrombi in blood vessels of human patients. In particular, some embodiments of the present technology relate to a self-locking syringe for generating and releasing a stored vacuum pressure to aspirate clot material from a blood vessel. [Background technology]

[0003] Thromboembolism is characterized by the blockage of blood vessels. Thromboembolic disorders, such as stroke, pulmonary embolism, heart attack, peripheral thrombosis, and atherosclerosis, affect many people and are major causes of morbidity and mortality.

[0004] When an artery is occluded by a clot, tissue ischemia develops. If the occlusion persists, ischemia progresses to tissue infarction. However, if blood flow is rapidly restored, infarction may not develop or may be severely limited. Thus, failure to reestablish blood flow can lead to limb loss, angina, myocardial infarction, stroke, and even death.

[0005] In the venous circulation, obstructive materials can also cause serious harm. Blood clots can develop in the large veins of the legs and pelvis, a common condition known as deep venous thrombosis (DVT). DVT typically occurs in situations prone to blood pooling (e.g., long-distance air travel, immobility) and clotting (e.g., cancer, recent surgery, such as orthopedic surgery). DVT can prevent venous blood from draining from the legs, leading to swelling, ulcers, pain, and infection. DVT can also create reservoirs where blood clots can collect and then travel to other parts of the body, including the heart, lungs, brain (stroke), abdominal organs, and / or limbs.

[0006] In the pulmonary circulation, unwanted substances can cause harm by obstructing the pulmonary arteries (a condition known as pulmonary embolism). If the obstruction is upstream in the main or major pulmonary artery bifurcation, it can significantly impair total blood flow within the lungs and therefore total blood flow throughout the body. This can lead to hypotension and shock. If the obstruction is downstream from the major pulmonary artery bifurcation in the middle pulmonary artery bifurcation, it can prevent a significant portion of the lung from participating in gas exchange with the blood, resulting in low blood oxygen and a buildup of blood carbon dioxide.

[0007] There are many existing techniques for reestablishing blood flow through an occluded blood vessel. For example, embolectomy is a surgical technique that involves cutting open the vessel and placing a balloon-tipped device (such as a Fogarty catheter) at the site of the occlusion. The balloon is then inflated beyond the clot and used to pull the occluding material back up to the incision point. The occluding material is then removed by the surgeon. While such surgical techniques are useful, exposing the patient to surgery can be traumatic and is best avoided when possible. Furthermore, the use of a Fogarty catheter can be problematic due to the potential risk of damaging the inner vessel wall as the catheter is being pulled back.

[0008] Percutaneous methods are also utilized to reestablish blood flow. A common percutaneous technique is called balloon angioplasty, in which a balloon-tipped catheter is introduced into a blood vessel (e.g., typically through an introducer catheter). The balloon-tipped catheter is then advanced to the point of occlusion and inflated to dilate the stenosis. While balloon angioplasty is suitable for treating vascular stenosis, it is generally ineffective for treating acute thromboembolic events because the obstructing material is not completely removed and restenosis regularly occurs after dilation. Another percutaneous technique involves placing a catheter near the clot and injecting streptokinase, urokinase, or other thrombolytic agents to dissolve the clot. Unfortunately, thrombolysis typically takes hours to days to be successful. Furthermore, thrombolytic agents can cause bleeding, and in many patients, thrombolytic agents cannot be used at all.

[0009] Various devices exist for performing thrombectomy or removing other foreign bodies. However, such devices have been found to have structures that are either overly complex, cause trauma to the treated vessel, or lack the ability to properly secure against the vessel. Furthermore, many of the devices have overly complex structures that lead to manufacturing and quality control difficulties, as well as delivery problems when passing through tortuous or small-diameter catheters. While less complex devices may allow users, especially inexperienced users, to pull through the clot, such devices may not completely capture and / or collect all of the clot material.

[0010] Therefore, a need exists for improved systems and methods for embolectomy. Summary of the Invention [Means for solving the problem]

[0011] The present technology is generally directed to self-locking syringes, such as for use in clot removal systems for aspirating clot material from a blood vessel of a human patient. In some embodiments, the self-locking syringe can include (i) a barrel, (ii) a locking plate coupled to the barrel, and (iii) a plunger slidably positioned within the barrel and having a locking feature configured to engage with the locking plate. The plunger also extends through an opening in the locking plate, and a biasing member is configured to bias the locking plate toward the locked position. When the plunger is moved through the barrel from the depressed position to the retracted position, the locking feature is configured to engage with the locking plate and drive the locking plate away from the locked position, thereby allowing the locking feature to pass through the opening in the locking plate. When the locking feature passes through the opening, the biasing member is configured to bias the locking plate to the locked position, preventing movement of the plunger from the retracted position to the depressed position. Thus, in one aspect of the present technology, the plunger is automatically locked in position via engagement of the locking plate with the locking feature when the plunger is pulled back a selected distance.

[0012] In additional embodiments, a self-locking syringe can include (i) a barrel having a flange, (ii) a plunger slidably positioned within the barrel, and (iii) at least one locking member coupled to the plunger. The locking member can include a body and a first arm hingedly coupled to the body. The first arm is configured to be biased at least partially outwardly, away from the longitudinal axis of the plunger, to a locked position. When the plunger is in the retracted position, the first arm can engage a flange of the barrel to prevent movement of the plunger through the barrel from the retracted position to the depressed position. The syringe can further include an actuator movable between a first position and a second position. The actuator can include a second arm configured to engage the first arm in the second position to drive the first arm inward toward the longitudinal axis and away from the locked position. Thus, when the plunger is retracted, moving the actuator from the first position to the second position can drive the first arm radially inward away from the locked position to enable movement of the plunger through the barrel from the retracted position to the depressed position. The present invention provides, for example, the following items. (Item 1) A self-locking syringe, Barrel and a plunger slidably positioned within the barrel, the plunger being movable between a depressed position and a retracted position, the plunger including a locking feature; a locking plate coupled to the barrel and having an opening extending therethrough, the plunger being slidably positioned within the opening, the locking plate including a biasing member configured to bias the locking plate to a locked position; when the plunger is moved from the depressed position to the retracted position, the locking feature is configured to engage the locking plate and drive the locking plate away from the locking position, thereby allowing the locking feature to pass through the opening; the biasing member is configured to drive the locking plate to the locked position after the locking feature passes through the opening, preventing movement of the plunger from the retracted position to the depressed position. (Item 2) Item 1, wherein the locking feature includes a stop surface extending generally perpendicular to a longitudinal axis of the syringe, and the locking plate is configured to engage the stop surface when (a) the locking plate is in the locked position and (b) the plunger is in the retracted position. (Item 3) 2. The syringe of claim 1, further comprising a button coupled to the locking plate, the button being operable to move the locking plate away from the locking position and allow movement of the plunger from the retracted position to the depressed position. (Item 4) Item 1, wherein the biasing member includes at least one of a spring and a living hinge. (Item 5) Item 2. The syringe according to item 1, wherein the biasing member is an arm hingedly connected to the locking plate. (Item 6) Item 10. The syringe of item 1, wherein the locking feature is one of a plurality of locking features positioned along the longitudinal axis of the plunger. (Item 7) when the plunger is moved from the depressed position to the retracted position, each of the locking features is configured to sequentially engage the locking plate and drive the locking plate to the position away from the locking position, thereby allowing the locking features to pass through the opening; 7. The syringe of claim 6, wherein the biasing member is configured to drive the locking plate to the locked position and prevent movement of the plunger from the retracted position to the depressed position after each of the locking features has sequentially passed through the opening. (Item 8) 7. The syringe according to item 6, further comprising a locking mechanism configured to engage the locking plate and lock the locking plate at the position away from the locked position. (Item 9) Item 10. The syringe according to item 1, wherein the barrel has a volume of about 60 cc or more. (Item 10) A self-locking syringe, a barrel including a flange; a plunger slidably positioned within the barrel, the plunger aligned along a longitudinal axis, the plunger movable along the longitudinal axis between a depressed position and a retracted position; a locking member coupled to the plunger, the locking member including a body and a first arm hingedly coupled to the body, the first arm configured to be biased at least partially outwardly, away from the longitudinal axis of the plunger, to a locked position; an actuator including a second arm, the actuator movable between a first position and a second position, the second arm configured to engage the first arm in the second position to drive the first arm inward toward the longitudinal axis and away from the locked position. (Item 11) Item 11. The syringe of item 10, wherein the first arm is configured to engage with the flange of the barrel to prevent movement of the plunger from the retracted position to the depressed position when (a) the actuator is in the first position and (b) the plunger is in the retracted position. (Item 12) Item 11. The syringe of item 10, wherein the locking member includes a third arm hingedly coupled to the body, the third arm configured to be biased at least partially outwardly, away from the longitudinal axis of the plunger, to a locked position; and the actuator includes a fourth arm configured to engage the third arm in the second position and drive the third arm inwardly, toward the longitudinal axis, away from the locked position. (Item 13) Item 13. The syringe of item 12, wherein the first arm is configured to be biased at least partially outwardly away from the longitudinal axis in the first direction, and the third arm is configured to be biased at least partially outwardly away from the longitudinal axis in a second direction opposite the first direction. (Item 14) Item 13. The syringe according to item 12, wherein the first arm and the third arm have the same size and shape, and the second arm and the fourth arm have the same size and shape. (Item 15) Item 13. The syringe of item 12, wherein the third arm is configured to engage with the flange of the barrel to prevent movement of the plunger from the retracted position to the depressed position when (a) the actuator is in the first position and (b) the plunger is in the retracted position. (Item 16) 1. A clot treatment system comprising: A catheter, a pressure source configured to generate a vacuum pressure; a tubing subsystem configured to fluidly connect the catheter to the pressure source, the tubing subsystem including a vacuum indicator configured to provide an indication that the catheter is under vacuum pressure. (Item 17) Item 17. The clot treatment system of item 16, wherein the tubing subsystem includes a window portion, and the vacuum indicator portion includes a flexible member positioned over the window portion, the flexible member configured to deform around the opening when the catheter is under vacuum pressure to provide the indication that the catheter is under vacuum pressure. (Item 18) Item 18. The clot treatment system of item 17, wherein the vacuum indicator comprises a housing positioned around the flexible member and configured to prevent excessive deformation of the flexible member when the catheter is under positive pressure. (Item 19) Item 17. The clot treatment device according to item 16, wherein the pressure source is a self-locking syringe. (Item 20) the tubing subsystem includes a valve, a first tubing section, a fluid control device, and a second tubing subsystem; the valve fluidly connects the catheter to the first tubing section; the first tubing section is fluidly connected between the valve and the fluid control device; the second tubing system fluidly connects the fluid control device to the pressure source; Item 17. The clot treatment device according to item 16, wherein the vacuum indicator is fluidly connected between the valve and the fluid control device. (Item 21) A syringe, a barrel having a tip, the tip including an opening; a plunger movable through the barrel to create a vacuum within the barrel; a vacuum indicator positioned over the opening in the tip, the vacuum indicator including a transparent tube and an indicator movably positioned within the tube, the indicator including a first portion having a first visual characteristic and a second portion having a second visual characteristic different from the first visual characteristic; the first portion is configured to be positioned adjacent to the tube when the barrel is not under vacuum pressure; The syringe, wherein the second portion is configured to be positioned adjacent to the tube when the barrel is under vacuum pressure. (Item 22) the vacuum indicator further includes an opaque cap over the tube, the indicator being movably positioned within the cap and the tube; the second portion is configured to be positioned adjacent to the cap when the barrel is not under vacuum pressure; 22. The syringe according to claim 21, wherein the first portion is configured to be positioned adjacent to the cap when the barrel is under vacuum pressure. (Item 23) Item 23. The syringe of item 22, wherein the vacuum indicator further includes a biasing member coupled between the indicator and the cap, the biasing member configured to bias the indicator to position the first portion adjacent to the tube when the barrel is not under vacuum pressure. (Item 24) 22. The syringe of claim 21, wherein the vacuum indicator is positioned over the opening in the tip and further includes a flexible member coupled to the indicator. (Item 25) Item 25. The syringe of item 24, wherein the flexible member is configured to deform around the opening when the catheter is under vacuum pressure. (Item 26) 25. The syringe of claim 24, wherein the vacuum indicator further comprises an opaque cap over the tube, the first portion of the indicator being coupled to the flexible member and the second portion of the indicator being coupled to the cap. (Item 27) 22. The syringe of claim 21, wherein the vacuum indicator further includes a flexible member positioned over the opening in the tip and a biasing member, the first portion of the indicator being coupled to the biasing member and the second portion of the indicator being coupled to the flexible member. (Item 28) 22. The syringe of claim 21, wherein the first and second portions of the indicia are movable relative to one another, and the second indicia is at least partially nested within the first indicia. [Brief explanation of the drawings]

[0013] Many aspects of the present technology can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure.

[0014] [Figure 1A] 1A and 1B are exploded isometric and side views, respectively, of a vacuum-locked syringe in accordance with an embodiment of the present technology; [Figure 1B] 1A and 1B are exploded isometric and side views, respectively, of a vacuum-locked syringe in accordance with an embodiment of the present technology; [Figure 2A] 1A and 1B are isometric views of the syringe of FIGS. 1A and 1B in depressed and retracted positions, respectively, in accordance with an embodiment of the present technology; [Figure 2B] 1A and 1B are isometric views of the syringe of FIGS. 1A and 1B in depressed and retracted positions, respectively, in accordance with an embodiment of the present technology; [Figure 3A] FIG. 3A is a side view of a syringe illustrating a step of locking a plunger of the syringe to a locking member of the syringe in accordance with an embodiment of the present technology, and FIGS. 3B and 3C are enlarged side views. [Figure 3B] FIG. 3A is a side view of a syringe illustrating a step of locking a plunger of the syringe to a locking member of the syringe in accordance with an embodiment of the present technology, and FIGS. 3B and 3C are enlarged side views. [Figure 3C] FIG. 3A is a side view of a syringe illustrating a step of locking a plunger of the syringe to a locking member of the syringe in accordance with an embodiment of the present technology, and FIGS. 3B and 3C are enlarged side views. [Figure 4] FIG. 13 is an enlarged isometric view of a portion of a syringe in accordance with an additional embodiment of the present technology. [Figure 5A] 13A and 13B are isometric and side views, respectively, of a syringe in a retracted position in accordance with an additional embodiment of the present technology; [Figure 5B] 13A and 13B are isometric and side views, respectively, of a syringe in a retracted position in accordance with an additional embodiment of the present technology; [Figure 5C] FIG. 5C is an isometric view of the syringe of FIGS. 5A and 5B in a depressed position in accordance with an embodiment of the present technology. [Figure 6A] FIG. 13 is a side view of a vacuum-locked syringe in accordance with an additional embodiment of the present technology. [Figure 6B] 6B is an enlarged side view of a locking mechanism of the syringe of FIG. 6A in a first position and a second position, respectively, in accordance with an embodiment of the present technology; [Figure 6C] 6B is an enlarged side view of a locking mechanism of the syringe of FIG. 6A in a first position and a second position, respectively, in accordance with an embodiment of the present technology; [Figure 7]1A-4, 5A-5C, and / or 6A-6C, in accordance with embodiments of the present technology. FIG. [Figure 8A] 8A-8C are enlarged, partial schematic side views of a vacuum sign of the clot removal system of FIG. 7 in a vacuum-off position and a vacuum-on position, respectively, in accordance with an embodiment of the present technology; [Figure 8B] 8A-8C are enlarged, partial schematic side views of a vacuum sign of the clot removal system of FIG. 7 in a vacuum-off position and a vacuum-on position, respectively, in accordance with an embodiment of the present technology; [Figure 9] FIG. 10 is a perspective view of a vacuum indicator in a vacuum off position in accordance with an additional embodiment of the present technology; [Figure 10A] 10A-10C are perspective views of a vacuum indicator in vacuum-off and vacuum-on positions, respectively, in accordance with an additional embodiment of the present technology; [Figure 10B] 10A-10C are perspective views of a vacuum indicator in vacuum-off and vacuum-on positions, respectively, in accordance with an additional embodiment of the present technology; [Figure 11] 1C is a side view of the syringe of FIGS. 1A and 1B including a vacuum indicator in accordance with an embodiment of the present technology. FIG. [Figure 12A] 13 is a perspective view of a syringe including a vacuum indicator in accordance with an additional embodiment of the present technology; FIG. [Figure 12B] 13 is a perspective view of a syringe including a vacuum indicator in accordance with an additional embodiment of the present technology; FIG. [Figure 13A] 10A-10C are side views of a vacuum indicator in a vacuum-off position, a partial vacuum position, and a full vacuum position, respectively, in accordance with an additional embodiment of the present technology; [Figure 13B] 10A-10C are side views of a vacuum indicator in a vacuum-off position, a partial vacuum position, and a full vacuum position, respectively, in accordance with an additional embodiment of the present technology; [Figure 13C] 10A-10C are side views of a vacuum indicator in a vacuum-off position, a partial vacuum position, and a full vacuum position, respectively, in accordance with an additional embodiment of the present technology; [Figure 14A] 13A-13D are isometric and top views of a syringe in accordance with an additional embodiment of the present technology; [Figure 14B] 13A-13D are isometric and top views of a syringe in accordance with an additional embodiment of the present technology; [Figure 14C] 14C are enlarged side views of the vacuum indicators of the syringe of FIGS. 14A and 14B in the "vacuum off" and "vacuum on" positions, respectively, in accordance with an embodiment of the present technology. [Figure 14D] 14C are enlarged side views of the vacuum indicators of the syringe of FIGS. 14A and 14B in the "vacuum off" and "vacuum on" positions, respectively, in accordance with an embodiment of the present technology. [Figure 14E] 14A-14D in vacuum-off and vacuum-on positions, respectively, in accordance with an embodiment of the present technology. [Figure 14F] 14A-14D in vacuum-off and vacuum-on positions, respectively, in accordance with an embodiment of the present technology. [Figure 14G] 14A-14F in a vacuum-off position in accordance with an embodiment of the present technology. FIG. [Figure 15A] 14A-14D are isometric and side views of a syringe in accordance with an additional embodiment of the present technology; [Figure 15B] 14A-14D are isometric and side views of a syringe in accordance with an additional embodiment of the present technology; [Figure 15C] 15C are enlarged side views of the vacuum indicators of the syringes of FIGS. 15A and 15B in the "vacuum off" and "vacuum on" positions, respectively, in accordance with an embodiment of the present technology. [Figure 15D] 15C are enlarged side views of the vacuum indicators of the syringes of FIGS. 15A and 15B in the "vacuum off" and "vacuum on" positions, respectively, in accordance with an embodiment of the present technology. [Figure 15E] 15A-15D in vacuum-off and vacuum-on positions, respectively, in accordance with an embodiment of the present technology. [Figure 15F] 15A-15D in vacuum-off and vacuum-on positions, respectively, in accordance with an embodiment of the present technology. [Figure 15G]15A-15F in a vacuum-off position in accordance with an embodiment of the present technology. FIG. [Figure 16] 15A-15G, further including a biasing member in accordance with an embodiment of the present technology. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0015] Specific details of various embodiments of the present technology are described herein with reference to FIGS. 1A-16. However, the present technology may be practiced without some of these specific details. In some instances, well-known structures and techniques often associated with the disclosed syringes, clot removal systems, and the like are not shown in detail so as not to obscure the present technology. The terms used in the description presented below are intended to be interpreted in their broadest reasonable manner, even when used in conjunction with the detailed description of certain embodiments of the present disclosure. Certain terms may even be emphasized below; however, any terms intended to be interpreted in any limited manner are so clearly and specifically defined in this detailed description section.

[0016] The accompanying drawings illustrate embodiments of the present technology and are not intended to limit its scope. The sizes of the various depicted elements are not necessarily drawn to scale, and these various elements may be arbitrarily enlarged to improve readability. Details of components may be abstracted in the drawings to exclude details such as the location of components and specific precise connections between such components when such details are not necessary for a complete understanding of how to make and use the present technology. Many of the details, dimensions, angles, and other features shown in the drawings are merely illustrative of particular embodiments of the present disclosure. Thus, other embodiments may have other details, dimensions, angles, and features without departing from the spirit or scope of the present technology.

[0017] With respect to the terms "distal" and "proximal" within this description, unless otherwise specified, these terms can refer to the relative position of portions of the catheter subsystem relative to the operator and / or location within the vasculature. Also, as used herein, designations such as "rear," "forward," "superior," "inferior," etc. are not meant to limit the referenced components to use in a particular orientation. It will be understood that such designations refer to the orientation of the referenced components as shown in the figures. The systems of the present technology can be used in any orientation suitable for the user.

[0018] The headings provided herein are for convenience only and should not be construed as limiting the subject matter disclosed.

[0019] I. SELECTED EMBODIMENTS OF VACUUM-PRESSURE LOCKED SYRINGES 1A and 1B are exploded isometric and side views, respectively, of a vacuum-locked syringe ("syringe 100") in accordance with an embodiment of the present technology. Syringe 100 is in a partially retracted position in FIG. 1B. Referring to both FIGS. 1A and 1B, syringe 100 includes a plunger 110 slidably positioned within a barrel 120. Barrel 120 is shown as partially transparent in FIG. 1B for clarity. Barrel 120 can include a barrel portion 122 (e.g., a cylindrical portion) extending between a flange 124 and a tip 126. In some embodiments, barrel portion 122 can have a volume of approximately 60 cc or greater. Tip 126 is configured to be releasably or permanently coupled to an adapter 130 (shown partially transparent in FIGS. 1A and 1B). In some embodiments, tip 126 can define a bore 128 having a size of approximately 26 French or greater. In the embodiment shown, adapter 130 is a Toomey tip adapter having a sealing member 132 (e.g., an O-ring) extending around its exterior surface for sealingly engaging (e.g., connecting) to a Toomey fitting or Toomey adapter. In other embodiments, adapter 130 can be omitted and tip 126 of barrel 120 can be directly coupled to another device or system (not shown), and / or tip 126 can be another type of tip, such as, for example, a luer lock, a locking slip, and / or a needle.

[0020] In the embodiment shown, plunger 110 includes a shaft 112 extending between a flange 114 and a gripping portion 116. The gripping portion 116 is configured to be grasped by a user to retract (e.g., retract, pull) and / or depress (e.g., advance, push) the plunger 110 through a barrel 120 during operation of the syringe 100. The plunger 110 may include a sealing member 118 positioned about the flange 114 and configured to sealingly engage an inner surface of the barrel portion 120 to define a sealed volume (e.g., of negative / vacuum pressure) within the barrel 122. Various components of the syringe 100 may include metal, plastic, and / or other suitable materials.

[0021] 1B , the shaft 112 of the plunger 110 includes a lower edge or surface 111 and a locking feature 113 extending / protruding from the surface 111. In the embodiment shown, the locking feature 113 includes (i) a sloped portion 115, (ii) a plateau portion 117 extending from the sloped portion 115, and (iii) a stop surface 119 extending from the plateau portion 117. The sloped portion 115 may extend / slope at an angle relative to the surface 111 (i) away from the surface 111 and (ii) in a direction toward the flange 114 of the plunger 110. The plateau portion 117 may extend generally parallel to the surface 111, away from the sloped portion 115, in a direction toward the flange 114. The stop surface 119 may extend away from the plateau portion 117 in a direction generally perpendicular to the surface 117 and the surface 111. In some embodiments, the locking feature 113 can be a tab, flat surface, half disk, and / or other feature extending from the lower surface 111 of the shaft 112 .

[0022] In the embodiment shown, the syringe 100 further includes a base 140 and a locking member 150 operably coupled to the base 140. In some embodiments, the base 140 can be coupled to the flange 124 of the barrel 120. Thus, the base 140 can couple the locking member 150 to the barrel 120. The base 140 can include a body 142 having an opening 143 extending therethrough and configured to slidably receive the shaft 112 of the plunger 110. The locking member 150 can include a locking plate 152 coupled to a button portion 154. The locking plate 152 can include an opening 153 (i) extending therethrough, (ii) defined by a rim portion 156, and (iii) configured to slidably receive the shaft 112 of the plunger 110. In some embodiments, locking member 150 can be movably coupled to base 140, for example, via a biasing member (e.g., arm 358 shown in FIGS. 3B and 3C , spring 460 shown in FIG. 4 , and / or another type of biasing member). As described in more detail below with reference to FIGS. 3A-4 , locking plate 152 is configured to engage locking feature 113 of plunger 110 when plunger 110 is retracted to the selected position, locking plunger 110 in the selected position. The selected position can correspond to a preselected vacuum volume in barrel 120. Button portion 154 is actuatable (e.g., depressible) by a user to release locking plate 152 from locking feature 113 and release plunger 110, e.g., to allow plunger 110 to move through barrel 120 and expel any contents collected within barrel 120 (e.g., bodily fluids such as blood and clot material) from tip 126.

[0023] 2A and 2B are isometric views of a syringe 100 in a depressed position (e.g., a first position, an empty position, a zero vacuum position) and a retracted position (e.g., a second position, a vacuum accumulation position, a vacuum generation position, a full vacuum position), respectively, in accordance with an embodiment of the present technology. The barrel 120 is shown as partially transparent in FIGS. 2A and 2B for clarity. Referring together to FIGS. 2A and 2B, generally, a user can move the syringe 100 from the depressed position to the retracted position by pulling the gripping portion 116 of the plunger 110 relative to the barrel 120 in the direction of arrow A (FIG. 2A) to retract the plunger 110 through the barrel 120, the base 140, and the locking member 150. In some embodiments, retracting the plunger 110 can create a vacuum (e.g., create a negative pressure) within the barrel 120. Additionally, locking plate 152 of locking member 150 can engage locking feature 113 (obscured in FIG. 2B ) of plunger 110 as plunger 110 is retracted past locking plate 152 to automatically lock plunger 110 in the retracted position. To move syringe 100 from the retracted position to the depressed position, a user can (i) actuate button portion 154 of locking member 150 (e.g., by depressing button portion 154 in the direction of arrow B in FIG. 2B ) to disengage locking plate 152 from locking feature 113 and unlock plunger 110 from locking member 150, and then (ii) push plunger 110 in the direction of arrow C ( FIG. 2B ) relative to barrel 120.

[0024] FIG. 3A is a side view of the syringe 100 illustrating the process of locking the plunger 110 to the locking member 150 in accordance with an embodiment of the present technology, and FIGS. 3B and 3C are enlarged side views. The syringe 100 is in a partially retracted position in FIGS. 3A and 3B. More specifically, FIGS. 3A and 3B show the syringe 100 as the locking feature 113 passes through the opening 153 (FIG. 1A) in the locking member 150 during retraction of the plunger 110 from the depressed position to the retracted position. FIG. 3C shows the syringe 100 after the locking feature 113 has been retracted past the locking plate 152 and through the opening 153. The barrel 120 is shown as partially transparent in FIGS. 3A-3C, and the base 140 is shown as partially transparent in FIGS. 3B and 3C for clarity.

[0025] 3B and 3C , locking member 150 further includes an arm 358 (e.g., a biasing member) that operably couples locking member 150 to base 140. In the embodiment shown, for example, arm 358 projects away from (e.g., perpendicular to) locking plate 152 and presses against (e.g., engages, attaches to) base 140. Arm 358 can be a spring arm, living hinge, lever arm, or other member that (i) is hingedly / movably coupled to locking member 150 and (ii) is configured to bias locking plate 152 upward to a locked position (e.g., a first position) as shown in FIGS. 3C and 1B (e.g., in the upward direction indicated by arrow D in FIG. 3C ). When the locking feature 113 is retracted past the locking plate 152, the locking feature 113 can engage with the locking plate 152 and drive the locking plate 152 away from the locked position (e.g., toward the second position) against the biasing force of the arm 358 as shown in FIG. 3B (e.g., downward as indicated by arrow E in FIG. 3B).

[0026] 3A and 3B , when plunger 110 is pulled back toward locking member 150 in the direction of arrow A, angled portion 115 of locking feature 113 first engages edge portion 156 ( FIG. 1A ) of locking plate 152 at first side 357 a of locking plate 152 opposite second side 357 b. As the plunger is pulled back further, angled angled portion 115 drives locking plate 152 (and button portion 154) downward in the direction of arrow E against the biasing force of arm 358 (e.g., away from the locked position) until locking plate 152 reaches plateau portion 117 of locking feature 113. That is, angled portion 115 of locking feature 113 translates the longitudinal force of plunger 110 into radial movement of locking plate 152. Continued retraction of plunger 110 causes locking plate 152 to slide over / against plateau portion 117 until locking feature 113 reaches stop surface 119. Referring to FIG. 3C , when locking plate 152 passes the end of plateau portion 117, arm 358 can drive locking plate 152 upward in the direction of arrow D to the locked position. Plunger 110 is then prevented from moving / advancing past locking plate 152 toward the depressed position (e.g., in the direction of arrow C shown in FIG. 2B ). Specifically, second side 357 b of locking plate 152 can engage / contact stop surface 119 of locking feature 113 to prevent advancement of plunger 110. In other embodiments, locking feature 113 and / or locking plate 152 can have different configurations / arrangements that facilitate locking plunger 110 in the retracted position. For example, in some embodiments, the plateau portion 117 of the locking feature 113 can be omitted.

[0027] To unlock plunger 110 from locking member 150, a user can actuate button portion 154 of locking member 150, for example, by pressing button portion 154 downward in the direction of arrow E. Movement of button portion 154 drives locking plate 152 downward relative to locking feature 113 until edge portion 156 ( FIG. 1A ) of locking plate 152 completely clears stop surface 119 of locking feature 113, thereby allowing movement of locking feature 113 through opening 153 ( FIG. 1A ) in locking plate 152. The user can then advance plunger 110 through barrel 120 to expel any contents collected in barrel 120.

[0028] Thus, in one aspect of the present technology, the plunger 110 is automatically locked in place via the locking plate 152 and the locking feature 113 when the plunger 110 is retracted a selected distance. In contrast, many conventional locking syringes require the user to rotate the plunger relative to the barrel to facilitate plunger locking. Such rotation can be difficult when the syringe has a large volume, e.g., 60 cc or more, and therefore requires a relatively large retraction force to retract the plunger. Thus, the syringe 100 of the present technology has improved usability compared to conventional locking syringes, particularly during procedures requiring multiple retractions of the plunger 110 over the course of the procedure. In some embodiments, the locking member 150 and the locking feature 113 can be configured (e.g., molded, positioned) so that the syringe 100 automatically locks at a selected position corresponding to a selected volume of the barrel 120. In some embodiments, the selected volume can be approximately 60 cc or more.

[0029] In another aspect of the present technology, syringe 100 is lockable in only a single position, which can be particularly useful when syringe 100 is used in a procedure where a single working volume is preselected / desired, such as during a clot removal procedure involving aspirating clot material from a blood vessel, as described in more detail below with reference to FIG.

[0030] FIG. 4 is an enlarged isometric view of a portion of a syringe 100 in accordance with an additional embodiment of the present technology. The barrel 120 is shown as partially transparent in FIG. 4 for clarity. In the illustrated embodiment, the locking plate 152 of the locking member 150 is operably coupled to the base 140 via a pair of springs 460 (only one of the springs 460 is visible in FIG. 4). The springs 460 are configured to bias the locking plate 152 to the first position shown in FIGS. 4 and 1B and may replace or supplement the arms 358 described in detail above with reference to FIGS. 3A-3C. More specifically, each of the springs 460 can be a compression spring operably coupled between a first spring mount 462 of the locking plate 152 and a second spring mount 464 of the body 142 of the base 140. In a manner similar to that described in detail above with reference to Figures 3A-3C, (i) locking feature 113 can engage locking plate 152 and drive locking plate 152 against the biasing force of spring 460 during retraction of plunger 110, and (ii) spring 460 can drive locking plate 152 upward after locking feature 113 has passed locking plate 152 to automatically lock plunger 110 in the retracted position.

[0031] 5A-5C are isometric, side, and another isometric view, respectively, of a syringe 500 in accordance with an additional embodiment of the present technology. The syringe 500 is in a retracted / retracted position in FIGS. 5A and 5B and in a depressed / advanced position in FIG. 5C. Referring together to FIGS. 5A-5C, the syringe 500 can include various features generally similar to or identical to the syringe 100 described in detail above with reference to FIGS. 1A-4. In the illustrated embodiment, for example, the syringe 500 includes a plunger 510 configured to be slidably positioned within a barrel 520. The barrel 520 is shown as partially transparent in FIGS. 5A-5C for clarity. The barrel 520 can include a barrel portion 522 extending between a flange 524 and a tip 526. In some embodiments, tip 526 is configured to be releasably or permanently coupled to an adapter 530 (e.g., a Toomey tip adapter, shown partially transparent in FIGS. 5A-5C ). Plunger 510 can include a shaft 512 extending between a flange 514 and a gripping portion 516. Plunger 510 can include a sealing member 518 positioned about flange 514 and configured to sealingly engage an inner surface of barrel portion 520 to define a sealed volume (e.g., of negative pressure / vacuum pressure) within barrel 522.

[0032] In the embodiment shown, syringe 500 further includes a pair of locking members 570 (individually identified as first locking member 570a and second locking member 570b) operably coupled to actuator 580. In some embodiments, shaft 512 of plunger 510 includes a spline 511 (e.g., a wall portion), and locking members 570 can be positioned on either side of spline 511. Locking members 570 can each include a body 572 and an arm 574 hingedly / movably attached to body 572. Arm 574 can be a spring arm, a living hinge, a lever arm, or other member configured to be biased outwardly away from longitudinal axis L ( FIG. 5A ) of syringe 500. Bodies 572 may each include a first end portion 573 and a second end portion 575 opposite first end portion 573, and may each include / define an elongated opening 576 extending between first end portion 573 and second end portion 575. Locking members 570 may be formed of plastic, metal, and / or other suitable material and may be a single, integral part (e.g., an injection molded part) or may be formed of separate parts that are joined together.

[0033] In the embodiment shown, actuator 580 includes a pusher portion 582 and a pair of elongated arms 584 (individually identified as first arm 584a and second arm 584b) extending away from pusher portion 582. In some embodiments, pusher portion 582 is slidably coupled to splines 511 of shaft 512 and configured to slide at least partially between (i) a first position in which pusher portion 582 abuts and / or is adjacent to gripping portion 516 of plunger 510, and (ii) a second position in which pusher portion 582 abuts and / or is adjacent to second end portion 575 of arm 574. Plunger 580 is shown in the second position in FIGS. 5A-5C . The first arm 584a can extend at least partially through an opening 576 in the first body 570a, and the second arm 584b can extend at least partially through an opening 576 in the second body 570b. In some embodiments, the arm 584 is slidably positioned within the opening 576 such that movement of the pushing portion 582 between the first and second positions advances / retracts the arm 584 through the opening 576. In some embodiments, in the first position, the arm 584 of the actuator 580 does not extend over the arm 574 of the locking member 570. In the second position, the arm 584 of the actuator 580 can extend over / around all or a portion of the arm 574 of the locking member 570 to move (e.g., pinch) the arm 574 inward toward the longitudinal axis L against the biasing force of the arm 574 (e.g., in the direction of arrow F in FIG. 5B ). Actuator 580 may be formed from plastic, metal, and / or other suitable materials and may be a single, integral piece or may be formed from separate pieces that are joined together.

[0034] 5A and 5B , the arm 574 of the locking member 570 is biased outward such that an end portion of the arm 574 engages the flange 524 of the barrel 520. Thus, the arm 574 prevents / locks the plunger 110 from further advancing into the barrel 520 toward the depressed position. To unlock the plunger 510, a user can press the pushing portion 582 of the actuator to move the pushing portion 582 at least partially from the first position to the second position (e.g., toward the barrel 520 and the locking member 570). Movement of the pushing portion 582 drives the arm 584 through the opening 576 in the body 572 and over / around the arm 574 of the locking member 570 to move the arm 574 inward toward the longitudinal axis L and out of engagement with the flange 524. The user can then advance plunger 510 toward the depressed position (FIG. 5C) to expel any contents collected in barrel 520.

[0035] Subsequently, to retract the plunger 510 from the depressed position to the retracted position, the user may first move the actuator 580 to a first position to free the arms 574 of the locking member 570 from the arms 584 of the actuator 580. Thus, the arms 574 of the locking member 570 may return to their outwardly biased position and, in some embodiments, may contact the inner surface of the barrel portion 522. Then, when the plunger 510 is retracted through the barrel 520, the arms 574 of the locking member 570 may (i) spring outward as they are retracted from the barrel 520 (e.g., after passing the flange 524) and (ii) spring back upon engaging the flange 524. Thus, in one aspect of the present technology, the plunger 510 is automatically locked in position via the arms 574 of the locking member 570 when the plunger 510 is retracted a selected distance.

[0036] In some embodiments, the locking members 570 can be configured (e.g., molded, positioned) so that the syringe 500 automatically locks at a selected position corresponding to a selected volume of the barrel 520. In some embodiments, the selected volume can be about 60 cc or greater. In some embodiments, the syringe 500 can include only one of the locking members 570 or more than two of the locking members 570.

[0037] FIG. 6A is a side view of a vacuum-locked syringe (“syringe 600”) in accordance with an additional embodiment of the present technology. Syringe 600 is shown in a depressed position in FIG. 6A . Syringe 600 may include various features generally similar to or identical to syringe 100, described in detail above with reference to FIGS. 1A-3C . In the embodiment shown, for example, syringe 600 includes a plunger 610 slidably positioned within a barrel 620. Barrel 620 is shown as partially transparent in FIG. 6A for clarity. Syringe 600 further includes a base 640 and a locking member 650 operably coupled to base 640. Locking member 650 includes a locking plate 652 coupled to a button portion 654. Plunger 610 includes a lower edge or surface 611 including a plurality of locking features 613 extending / protruding from the lower surface 611. Each of the locking features 613 may include (i) a sloped portion 615 , (ii) a plateau portion 617 extending from the sloped portion 615 , and (iii) a stop surface 619 extending from the plateau portion 617 .

[0038] When the plunger 610 is retracted through the barrel 620, the locking features 613 are configured to engage the locking plates 652 to automatically lock the plunger 610 in a retracted position corresponding to the position of the locking features 613. More specifically, a user can retract the plunger 610 to a desired location / volume, and the locking feature 613 closest to the locking plate 652 can engage the locking plate 652 to automatically lock the plunger 610 in place. To move the syringe 600 from the retracted position to the depressed position, the user can (i) actuate the button portion 654 of the locking member 650 to disengage the locking plate 652 from the locking features 613 and unlock the plunger 610 from the locking member 650, and then (ii) push the plunger 610 against the barrel 620. In one aspect of the present technology, the syringe 600 includes multiple ones of the locking features 613 that allow the syringe 600 to be automatically locked in multiple different positions. In the embodiment shown, plunger 610 includes twelve locking features, however, in other embodiments, syringe 600 can include any number of locking features 613 to facilitate locking syringe 600 in any desired position / volume. Additionally, the location of locking features 613 can be selected to provide precise volume and vacuum control.

[0039] In the embodiment shown, the syringe 600 further includes a locking mechanism 690 operable to enable / disable the automatic locking feature of the syringe 600. More specifically, FIGS. 6B and 6C are enlarged side views of the locking mechanism 690 of the syringe 600 in a first position and a second position, respectively, in accordance with an embodiment of the present technology. Referring together to FIGS. 6B and 6C , the locking mechanism 690 may include a pin 692 operably coupled to the base 650 via a biasing member 694. In the embodiment shown, the pin 692 includes a head portion 693 and an engagement portion 695. The biasing member 694 may be operably coupled between the head portion 693 and the base 640, and the engagement portion 695 may extend at least partially through a channel 696 in the base 640. The locking member 650 may include an opening 698 configured to receive the engagement portion 695 of the pin 692 in the first position shown in FIG. 6B .

[0040] 6B , biasing member 694 (e.g., a tension spring) biases locking pin 692 toward locking member 650 such that engagement portion 695 is positioned in opening 698. Referring to both FIGS. 6A and 6B , in the first position, locking member 650 is partially depressed such that locking feature 613 slides freely past locking plate 652 without engaging locking plate 652. Thus, plunger 610 can be pulled back / depressed through barrel 620 without locking feature 613 automatically locking syringe 600, and thus syringe 600 functions similarly to a conventional syringe when locking mechanism 690 is in the first position. To activate the automatic locking feature of the syringe 600, a user can pull the pin 692 (e.g., head portion 693) away from the locking member 650 (e.g., against the biasing force of the biasing member 694) to retract the engagement portion 695 from the opening 698 and disengage the engagement portion 695 from the locking member 650. Thus, in the second position, the locking member 650 is operable to engage the locking feature 613 to auto-lock the syringe 600 (e.g., the locking member 650 can be biased as described with reference to FIGS. 3A-4 ). In other embodiments, the pin 692 can be operably coupled to the locking member 650 and configured to engage the base 640. In some embodiments, the syringe 100 and / or syringe 500 described in detail with reference to FIGS. 1A-5C can include the same or similar locking mechanisms for enabling / disabling the automatic locking feature.

[0041] II. SELECTED EMBODIMENTS OF THE CLOMATIC TREATMENT SYSTEM 7 is a partial schematic side view of a clot treatment or clot removal system including an aspiration assembly 700 ("assembly 700") incorporating syringe 100, syringe 500, and / or syringe 600, in accordance with an embodiment of the present technology. In the embodiment shown, assembly 700 includes a catheter subsystem 710 fluidly coupled to a tubing subsystem 720. Generally, assembly 700 (i) may include features generally similar or identical to those of the aspiration assembly described in detail in U.S. patent application Ser. No. 16 / 536,185, entitled "SYSTEM FOR TREATING EMBOLISM AND ASSOCIATED DEVICES AND METHODS," filed August 8, 2019, and incorporated herein by reference in its entirety, and / or (ii) may be used to treat / remove clot material from a patient (e.g., a human patient) using any of the methods described in detail therein.

[0042] In the embodiment shown, the catheter subsystem 710 includes a catheter 702 (e.g., an aspiration catheter) comprising an elongate shaft defining a lumen 704 and having a distal portion 703 and a proximal portion 705. The catheter subsystem 710 further includes a valve 706 that can be integral with or coupled to the proximal portion 705 of the catheter 702. In some embodiments, the valve is a hemostatic valve configured to maintain hemostasis during a clot removal procedure by preventing proximal fluid flow through the valve 706 when various components, such as a delivery sheath, tensioning member, guidewire, interventional device, or other aspiration catheter, are inserted through the valve 706 and delivered through the catheter 702 to a treatment site in a blood vessel. The valve 706 includes a branch or side port 708 configured to fluidly couple the lumen 704 of the catheter 702 to the tubing subsystem 720. In some embodiments, the valve 706 can be a valve of the type disclosed in U.S. Patent Application No. 16 / 117,519, filed August 30, 2018, entitled "HEMOSTASIS VALVES AND METHODS OF USE," the entire contents of which are incorporated herein by reference.

[0043] Tubing subsystem 720 fluidly couples catheter subsystem 710 to syringe 100, syringe 500, and / or syringe 600 (collectively "syringes 100 / 500 / 600"). More specifically, tubing subsystem 720 can include one or more tubing sections 724 (individually labeled as first tubing section 724a and second tubing section 724b), at least one fluid control device 726 (e.g., a valve), and at least one connector 728 (e.g., a Toomey tip connector) for fluidly coupling tubing subsystem 720 to syringe 100 / 500 / 600 and / or other suitable components. More specifically, in the embodiment shown, the fluid control device 726 is a stopcock that is fluidly coupled to (i) the side port 708 of the valve 706 via a first tubing section 724a and (ii) the connector 728 via a second tubing section 724b.

[0044] The fluid control device 726 is externally operable by a user to regulate the flow of fluid therethrough, specifically from the lumen 704 of the catheter 702 to the syringe 100 / 500. In some embodiments, the connector 728 is a quick-release connector (e.g., a quick-disconnect fitting) that enables rapid coupling / detachment of the catheter 702 and fluid control device 726 to / from the syringe 100 / 500 / 600.

[0045] 1A-7 together, syringe 100 / 500 / 600 is configured to generate (e.g., form, create, fill, store) a vacuum (e.g., a negative relative pressure) and store the vacuum for subsequent application to catheter subsystem 710. For example, during operation of assembly 700, a user can first close fluid control device 726 (i) before pulling back plunger 110 of syringe 100 until plunger 110 automatically locks to increase vacuum pressure within barrel 120 of syringe 100, (ii) before pulling back plunger 510 of syringe 500 until plunger 510 automatically locks to increase vacuum pressure within barrel 520 of syringe 500, and / or (iii) before pulling back plunger 610 of syringe 600 until plunger 610 automatically locks in a position corresponding to one of locking features 613. In this manner, a vacuum is built up (e.g., a negative pressure is maintained) within the syringe 100 / 500 / 600 before the syringe 100 / 500 / 600 is fluidly connected to the catheter subsystem 710. To aspirate the lumen 704 of the catheter 702, the user opens the fluid control device 726 to fluidly connect the syringe 100 / 500 / 600 to the catheter subsystem 710, thereby allowing the vacuum built up in the syringe 100 / 500 / 600 to be applied or released to the lumen 704 of the catheter 702.

[0046] Release of the fluid control device 726 instantaneously or near-instantaneously applies the stored vacuum pressure to the tubing subsystem 720 and the catheter 702, thereby generating a suction pulse throughout the catheter 702. In particular, suction is applied at the distal portion 703 of the catheter 702. In one aspect of the present technology, pre-priming or storing vacuum in the syringe 100 / 500 / 600 prior to applying vacuum to the lumen 704 of the catheter 702 is expected to generate a greater suction force and corresponding fluid flow rate at and / or near the distal portion 703 of the catheter 702 compared to simply actuating the syringe 100 / 500 / 600 while fluidly connected to the catheter 702. When the distal portion 703 is positioned within a blood vessel near clot material within a patient (e.g., a human patient), the suction force generated by application of the stored vacuum can be used to aspirate or otherwise remove the clot material from within the patient's blood vessel.

[0047] III. SELECTED EMBODIMENTS OF VACUUM INDICATIONS 7, in some embodiments, assembly 700 can include a vacuum indicator 730 (shown schematically) operably coupled to tubing subsystem 720. As described in more detail below with reference to FIGS. 8A and 8B, vacuum indicator 730 can provide an indication, such as a visual indication, of whether assembly 700 is under vacuum pressure. In the embodiment shown, vacuum indicator 730 is operably coupled to tubing subsystem 720 between fluid control device 726 and valve 706 (e.g., to first tubing section 724a and between a separate portion of first tubing section 724a). In other embodiments, vacuum indicator 730 can be operably coupled to tubing subsystem 720 between fluid control device 726 and connector 728 (e.g., to second tubing section 724b and between a separate portion of second tubing section 724b).

[0048] 8A and 8B are enlarged, partial schematic side views of a vacuum indicator 730 in a vacuum-off position and a vacuum-on position, respectively, in accordance with an embodiment of the present technology. Referring to both FIGS. 8A and 8B, the vacuum indicator 730 includes a body 832 and a flexible member 834 operably coupled to the body 832. The flexible member 834 is shown as partially transparent in FIGS. 8A and 8B for clarity. In some embodiments, the body 832 is a unitary or one-piece member of plastic, metal, or another suitable rigid material. The body 832 may include a first connector portion 836a (e.g., a first barb), a second connector portion 836b (e.g., a second barb), and a central portion 838 extending between the first and second connector portions 836a,b. The body 832 may further define a lumen 837 extending therethrough between the first and second connector portions 836a,b. The first connector portion 836a can be coupled to the first tube 825a, and the second connector portion 836b can be coupled to the second tube 825b. In some embodiments, the first and second tubes 825a,b can together form a first tubing section 724a (FIG. 7) such that the vacuum indicator 730 is fluidly coupled between the fluid control device 726 and the valve 706.

[0049] In the embodiment shown, central portion 838 of body 832 includes / defines (i) a recess 840 extending circumferentially therearound and (ii) an opening 842 positioned in recess 840 and extending through central portion 838 to lumen 837. In some embodiments, recess 840 can have a different shape and / or can extend only partially around central portion 838, and / or body 832 can include more than one opening 842 positioned in recess 840. Flexible member 834 can be a thin, compliant tube positioned over recess 840 and opening 842. In some embodiments, opposing end portions of flexible member 834 are secured to body 832 via first and second mounting members 844 a, 844 b. The first and second mounting members 844a,b may comprise adhesives, welds, fasteners, collars, or other components that mechanically secure the flexible member 834 over the recess 840 such that the flexible member 834 forms a seal over the recess 840. In some embodiments, the flexible member 834 may have a thickness between about 0.005 inches and about 0.100 inches.

[0050] 7, when assembly 700 is not under vacuum, flexible member 834 is positioned over recess 840 in a relaxed state such that flexible member 834 has a generally cylindrical shape, as shown in FIG. 8A. When a vacuum is generated in assembly 700, the vacuum is applied to flexible member 834 through opening 842, pulling / sucking flexible member 834 into recess 840, as shown in FIG. 8B. The deformation of flexible member 834 provides a visual indication to a user of assembly 700 that assembly 700 is under vacuum. When the vacuum is released, flexible member 834 returns / bounces back to the vacuum-off position shown in FIG. 8A, providing a visual indication that assembly 700 is not under vacuum.

[0051] In some embodiments, the thickness of flexible member 834, the size of openings 842, and / or the number of openings 842 can be selected so that flexible member 834 deforms to the vacuum-on position ( FIG. 8B ) and returns to the vacuum-off position ( FIG. 8A ) at a selected vacuum level. For example, making flexible member 834 thinner will result in it collapsing under a lower vacuum, while making flexible member 834 thicker will require a higher vacuum to collapse. Similarly, a thinner flexible member 834 is less likely to bounce back to the vacuum-off position ( FIG. 8A ) and therefore requires more pressure (e.g., positive pressure) to bounce back, while a thicker flexible member 834 will bounce back with little or no pressure.

[0052] In some embodiments, vacuum indicator 730 can include a housing 846 (shown schematically) that at least partially surrounds flexible member 834. Housing 846 can be formed of a rigid material (e.g., plastic, metal) and can be coupled to body 832. In some embodiments, housing 846 is configured to inhibit or prevent excessive deformation of flexible member 834 when assembly 700 is under positive pressure. For example, when positive pressure is applied to assembly 700, flexible member 834 can deflect outward, away from body 832, and contact housing 846. Thus, housing 846 can inhibit flexible member 834 from deflecting further outward and damaging or rupturing flexible member 834.

[0053] In some aspects of the present technology, the vacuum indicator 730 can assist a user during a clot removal procedure on a patient using the assembly 700. At times, for example, after applying a vacuum built up in the syringe 100 / 500 / 600 to the lumen 704 of the catheter 702, the clot material can at least partially clog the distal portion 703 of the catheter 702, causing cavitation in the assembly 700. In such instances, it is often desirable to remove the assembly 700 from the patient, thereby removing the clot material clogging and / or adhering to the distal portion 703 of the catheter 702. However, user error and / or a leak in the assembly 700 (e.g., from the valve 706) can dissipate the vacuum in the assembly 700, thereby releasing and / or reducing the force holding the clot material to the catheter 702. The vacuum indicator 730 can provide a quick and easy visual indication to the user of whether the assembly 700 is maintaining a vacuum. Thus, based on the position of vacuum indicator 730, the user can decide how to proceed with the procedure, for example, whether to continue to retract assembly 700 from the patient.

[0054] In some aspects of the present technology, the vacuum indicator 730 is a passive device that adds little or no volume to the flow path of the assembly 700. Adding volume to the flow path of the assembly 700 can reduce the amount of suction that can be generated at the distal portion 703 of the catheter 702. Thus, the vacuum indicator 730 can provide an indication of vacuum (e.g., on or off) without adversely affecting the clot removal capabilities of the assembly 700. In contrast, for example, a vacuum gauge coupled along the flow path of the assembly 702 increases its volume, decreasing the suction power of the assembly 700. Furthermore, the recess 840 can have a relatively small volume so that the vacuum indicator 730 is less likely to become clogged during use of the assembly 700 (e.g., by a blood clot during a thrombectomy procedure using the assembly 700). In contrast, a vacuum gauge or similar mechanism can be more susceptible to clogging, rendering them inoperable.

[0055] FIG. 9 is a perspective view of a vacuum indicator 930 in a vacuum-off position in accordance with an additional embodiment of the present technology. The vacuum indicator 930 may include certain features, functions, and / or advantages that are generally similar or identical to the vacuum indicator 730 described in detail above with reference to FIGS. 8A and 8B . For example, in the illustrated embodiment, the vacuum indicator 930 includes a body 932 and a flexible member 934 operably coupled to the body 932. The flexible member 934 is shown as partially transparent in FIG. 9 for clarity. The body 932 may include a first connector portion 936 a (e.g., a first barb), a second connector portion 936 b (e.g., a second barb), and a central portion 938 extending between the first and second connector portions 936 a, b. The body 932 may further define a lumen 937 extending therethrough between the first and second connector portions 936 a, b. The first and second connector portions 936a,b can be coupled to various tubes of, for example, the first tubing section 724a and / or the second tubing section 724b (FIG. 7).

[0056] In the embodiment shown, the central portion 938 of the body 932 includes / defines a plurality of longitudinal openings 950 that extend through the central portion 938 to the lumen 937. In some embodiments, the openings 950 can be evenly spaced around the body 932. In other embodiments, the central portion 938 can include more or fewer openings 950 and / or the openings 950 can be positioned differently around the central portion 938. The flexible member 934 can be a thin, compliant tube that is sealingly secured to the body 932 over the openings 950 via first and second mounting members 944 a, 944 b.

[0057] 7, when assembly 700 is not under vacuum, flexible member 934 is positioned over openings 950 in a relaxed state such that flexible member 934 has a generally cylindrical shape, as shown in FIG. 9. When a vacuum is generated in assembly 700, the vacuum is applied to flexible member 934 through openings 950, pulling flexible member 934 at least partially into one or more of openings 950. The deformation of flexible member 934 provides a visual indication to a user of assembly 700 that assembly 700 is under vacuum. When the vacuum is released, flexible member 934 can return to the vacuum-off position shown in FIG. 9, providing a visual indication that assembly 700 is not under vacuum. In some embodiments, vacuum indicator 930 can include a housing (not shown) that at least partially surrounds flexible member 934 and is configured to inhibit or even prevent excessive deformation of flexible member 934 when assembly 700 is under positive pressure.

[0058] 10A and 10B are perspective views of a vacuum indicator 1030 in a vacuum-off position and a vacuum-on position, respectively, in accordance with an additional embodiment of the present technology. The vacuum indicator 1030 may include certain features, functions, and / or advantages that are generally similar or identical to the vacuum indicator 730 and / or vacuum indicator 930 described in detail above with reference to FIGS. 8A-9. For example, referring to both FIGS. 10A and 10B, the vacuum indicator 930 includes a flexible member 934 that is fluidly coupled to a tube 1025. In some embodiments, the tube 925 is part of the first tubing section 724a or the second tubing section 724b (FIG. 7).

[0059] However, in the embodiment shown, the flexible member 1034 is attached directly to the tube 1025 over a hole or opening 1027 in the tube 1025 (obscured and shown schematically in FIG. 10A ). In some embodiments, opposing end portions of the flexible member 1034 are secured to the tube 1025 via a first mounting member 1044 a and a second mounting member 1044 b. The first and second mounting members 1044 a, b can be clamps, collars, or other mechanical components that mechanically secure the flexible member 1034 over the opening 1027 such that the flexible member 1034 forms a seal over the opening 1027. The first and second mounting members 1044 a, b can be secured to the tube 1025 via compression, adhesive, fasteners, and / or other suitable connection means. In some embodiments, the opening 1027 can have a diameter of about 0.100 inches to about 0.300 inches.

[0060] 7, when assembly 700 is not under vacuum, flexible member 1034 is positioned over opening 1027 in a relaxed state such that flexible member 1034 has a generally cylindrical shape, as shown in FIG. 10A. When a vacuum is generated in assembly 700, the vacuum is applied to flexible member 1034 through opening 1027, pulling flexible member 1034 into opening 1027, as shown in FIG. 10B. The deformation of flexible member 1034 provides a visual indication to a user of assembly 700 that the assembly is under vacuum. When the vacuum is released, flexible member 1034 returns to the vacuum-off position shown in FIG. 10A, providing a visual indication that assembly 700 is not under vacuum.

[0061] In some embodiments, a syringe constructed in accordance with the present technology can include a vacuum indicator integrated therewith. For example, FIG. 11 is a side view of the syringe 100 of FIGS. 1A and 1B including a vacuum indicator 1130 formed in the adapter 130 in accordance with an embodiment of the present technology. In the embodiment shown, the vacuum indicator 1130 includes a flexible member 1134 sealingly positioned over an opening 1152 in the adapter 130. The flexible member 1134 can be formed from a compliant material such as silicone and can have a dome-like shape in the vacuum-off position shown in FIG. 7 . With additional reference to FIG. 7 , when the syringe 100 is coupled to the system 700 (e.g., connector 728) and the plunger 110 is pulled back to draw a vacuum in the barrel 120, the vacuum is applied to the flexible member 1134 through the opening 1152, pulling the flexible member 1134 into / toward the opening 1152. For example, flexible member 1134 can invert when assembly 700 is under vacuum. The inversion / deformation of flexible member 1134 provides a visual indication to a user of assembly 700 that assembly 700 is under vacuum. When the vacuum is released, flexible member 1134 can passively return to the vacuum-off position shown in FIG. 11 , providing a visual indication that assembly 700 is not under vacuum.

[0062] 12A and 12B are perspective views of a syringe 1200 including a vacuum indicator 1230 in accordance with an additional embodiment of the present technology. The syringe 1200 is in a retracted position in FIG. 12B. Referring to both FIGS. 12A and 12B, the syringe 1200 includes a plunger 1210 slidably positioned within a barrel 1220. The barrel 1220 is shown as partially transparent in FIG. 1B for clarity. The plunger 1210 includes a flange 1214 configured to sealingly engage an inner surface of the barrel 1220 to define a sealed volume 1217 (FIG. 12B: e.g., of negative / vacuum pressure) within the barrel 1220.

[0063] In the embodiment shown, the vacuum indicator portion 1230 includes a housing 1260 (shown as partially transparent in FIGS. 12A and 12B ) coupled to the plunger 110 and defining a lumen 1262. The flange 1214 may include a through-hole 1264 that fluidly couples the lumen 1262 of the housing 1260 to the sealed volume 1217 within the barrel 1220. The vacuum indicator portion 1230 may further include an indicator member 1266 slidably positioned within the lumen 1262. The indicator member 1266 may be an elongated member and, in some embodiments, may have a color that contrasts with the color of the housing 1260 (e.g., a relatively light color). In some embodiments, the indicator member 1266 is configured to sealingly engage the housing 1260. For example, housing 1260 can include one or more sealing members (e.g., O-rings, not shown) on an inner surface thereof, and / or indicator member 1266 can include one or more sealing members (e.g., O-rings, not shown) on an outer surface thereof to provide a dynamic seal between housing 1260 and indicator member 1266. In the embodiment shown, indicator member 1266 is operably coupled to flange 1214 via biasing member 1268 extending through lumen 1262. Biasing member 1268 (e.g., a compression spring) is configured to bias indicator member 1266 through lumen 1262 in a direction away from flange 1214 (e.g., as indicated by arrow F in FIG. 12A ).

[0064] 7, when syringe 1200 is coupled to system 700 (e.g., connector 728) and plunger 1210 is pulled back to draw a vacuum in sealed volume 1217 of barrel 1220, the vacuum is applied to indicator member 1266 through through-hole 1264 in flange 1214 and lumen 1262 in housing 1260. The vacuum pulls indicator member 1266 through lumen 1262 against the biasing force of biasing member 1268, as indicated by arrow G in FIG. 12B. The positioning of indicator member 1266 relative to housing 1260 can provide a visual indication to a user of assembly 700 that assembly 700 is under vacuum. In some embodiments, for example, when plunger 1210 is fully retracted, indicator member 1266 can be positioned fully within lumen 1262, as shown in FIG. 12B, and thus obscured by housing 1260. When vacuum is released, biasing member 1268 drives indicator member 1266 through lumen 1262 in the direction of arrow F at least partially outside of housing 1260 (e.g., as shown in FIG. 12A), providing a visual indication that assembly 700 is not under vacuum. In some aspects of the present technology, the position of indicator member 1266 relative to housing 1260 can provide an indication of the varying level of vacuum in assembly 700 (e.g., as opposed to a binary on / off indication).

[0065] In some embodiments, the plunger 1210 includes a gripping portion 1216 configured to engage the indicator member 1266 and prevent further movement of the indicator member 1266 in the direction of arrow F when the assembly 700 is under positive pressure, as shown in FIG. 12A. In some embodiments, any of the vacuum-locked syringes 100 / 500 / 600 described in detail above with reference to FIGS. 1A-6C can include a vacuum indicator portion 1230.

[0066] 13A-13C are side views of a vacuum indicator device or vacuum indicator 1330 in a vacuum-off position, a partial vacuum position, and a full vacuum position, respectively, in accordance with an additional embodiment of the present technology. Referring together to FIGS. 13A-13C, the vacuum indicator 1330 includes a sealing indicator 1370 slidably positioned within a barrel 1320. The barrel 1320 includes a cap 1371 (e.g., a sealing cap) and a tip 1326 (e.g., a luer connector) that can be directly coupled to another device or system, such as the fluid control device 726 (e.g., a stopcock) of FIG. 7, as shown in FIGS. 13B and 13C.

[0067] In some embodiments, the sealing indicia 1370 is configured to sealingly engage the barrel 1320 to define a first volume or chamber 1372 and a second volume or chamber 1374 within the barrel 1320. For example, the sealing indicia 1370 can include one or more sealing members (e.g., O-rings, not shown) on an outer surface thereof to provide a dynamic seal between the barrel 1320 and the sealing indicia 1370. In some embodiments, the one or more sealing members can engage the barrel 1320 with low friction to facilitate sliding movement of the sealing indicia 1370 within the barrel 1320. The first chamber 1372 can be a sealed volume with no outlet, while the second chamber 1374 can be open to the tip 1326.

[0068] 7, when assembly 700 is not under vacuum pressure, seal indicator 1370 can be positioned near the top of barrel 1320 adjacent cap 1371. When syringe 100 / 500 / 600 is used to generate a vacuum in assembly 700, vacuum pressure is generated in second chamber 1374. The vacuum pressure in second chamber 1374 pulls seal indicator 1370 downward toward tip 1326 of barrel 1320, as shown in FIG. 13B. When seal indicator 1370 moves downward, away from cap 1371, the volume of first chamber 1372 increases, thereby generating vacuum pressure in first chamber 1372. The vacuum pressure created in the first chamber 1372 provides a resistive force that acts against the vacuum force in the second chamber 1374 to urge the seal indicator 1370 upward toward the cap 1371. The vacuum force in the second chamber 1374 must overcome the resistive vacuum force in the first chamber 1372 to move the seal indicator 1370 downward through the barrel 1320. In some embodiments, the vacuum indicator 1370 is configured (e.g., shaped, sized) so that the seal indicator 1370 abuts the tip 1326 of the barrel 1320 in a full vacuum position, as shown in FIG. 13C , to indicate that a maximum vacuum level has been created in the assembly 700. When the vacuum force dissipates or is lost in the assembly 700, the resistive vacuum force in the first chamber 1372 can move the seal indicator 1370 back toward the vacuum-off position shown in FIG. 13A .

[0069] Generally, the opposing vacuum forces in the first and second volumes 1372, 1374, along with the frictional forces between the barrel 1320 and the seal indicator 1370, dictate the speed and location of movement of the seal indicator 1370 along the barrel 1320. In some aspects of the present technology, the vacuum indicator 1330 can provide continuous resolution of vacuum level at higher vacuum levels (e.g., greater than 25 inHg). That is, the position of the seal indicator 1370 on the barrel 1320 can indicate a particular vacuum level in the assembly 700.

[0070] 14A and 14B are isometric and top views of a syringe 1400 in accordance with an additional embodiment of the present technology. The syringe 1400 is in a depressed / advanced position in FIGS. 14A and 14B. Referring together to FIGS. 14A and 14B, the syringe 1400 can include various features generally similar to or identical to the syringe 100 described in detail above with reference to FIGS. 1A-4 and can be coupled to the assembly 700 of FIG. 7 for use in a clot removal procedure. In the embodiment shown, for example, the syringe 1400 includes a plunger 1410 configured to be slidably positioned within a barrel 1420. The barrel 1420 is shown as partially transparent in FIGS. 14A and 14B for clarity. The barrel 1420 can include a barrel portion 1422 and a tip portion 1426. The plunger 1410 can include a shaft 1412 and a grip portion 1416. The syringe 1400 further includes a base 1440 and a locking member 1450 having a locking plate 1452 (obscured in FIG. 14B and partially obscured in FIG. 14A ) and a button portion 1454. The locking member 1450 is configured to automatically engage the base 1440 when the plunger 1410 is retracted to automatically lock the plunger 1410 in the retracted position, as described in detail above. The button portion 1454 can be actuable (e.g., depressible) by a user to release the locking plate 1452 from the base 1440 and release the plunger 1410, for example, to allow the plunger 1410 to move through the barrel 1420 and expel any contents collected within the barrel 1420 (e.g., bodily fluids such as blood and clot material) from the tip 1426. However, in the embodiment shown, the button portion 1454 extends generally parallel to the grip portion 1416 of the plunger 1410 .

[0071] Additionally, in the embodiment shown, the syringe 1400 further includes a vacuum indicator 1430 formed on and / or coupled to the tip 1426. FIGS. 14C and 14D are enlarged side views of the vacuum indicator 1430 in the "vacuum off" and "vacuum on" positions, respectively, in accordance with an embodiment of the present technology. FIGS. 14E and 14F are enlarged, partially see-through side views of the vacuum indicator 1430 in the vacuum off and vacuum on positions, respectively, in accordance with an embodiment of the present technology. FIG. 14G is an enlarged, side cross-sectional view of the vacuum indicator in the vacuum off position in accordance with an embodiment of the present technology. Referring together to FIGS. 14E-14G, the vacuum indicator 1430 can include a flexible member 1434 (e.g., a diaphragm, a rolling diaphragm) sealingly positioned over an opening 1461 in the tip 1426. The flexible member 1434 can be formed from a compliant material, such as silicone.

[0072] 14C-14G together, in the embodiment shown, the vacuum indicator 1430 further includes (i) a non-transparent (e.g., opaque) bonnet or base 1435 positioned around and / or coupled to the flexible member 1434, (ii) a transparent tube 1437 coupled to and extending from the base 1435, and (iii) a non-transparent cap 1439 coupled to and positioned over the tube 1437. The base 1435, the tube 1437, and / or the cap 1439 can be integrally formed or can be separate components coupled to one another. The vacuum indicator 1430 can further include an indicator 1460 movably positioned within the tube 1437 and the cap 1439. The indicia portion 1460 can include a first indicia region 1462 and a second indicia region 1464, each having at least one visual characteristic (e.g., color, pattern, size, thickness, shape) that differs from the other. For example, in some embodiments, the first indicia region 1462 can be a first color (e.g., red), while the second indicia region 1464 can be a different second color (e.g., green). In some embodiments, a first end portion of the indicia portion 1460 (e.g., a lower end of the first indicia region 1462) can be coupled to the flexible member 1434, and a second end portion of the indicia portion 1460 (e.g., an upper end of the second indicia region 1464) can be coupled to the cap 1439 via a biasing member 1466 ( FIGS. 14F and 14G ), such as a spring. As best seen in FIG. 14G, in some embodiments, the biasing member 1466 can extend at least partially through an internal channel 1469 of the indicator portion 1460.

[0073] When the tip 1426 of the syringe 1400 is not under vacuum, the vacuum indicia 1430 is in a vacuum-off position in which the biasing member 1466 biases the indicia 1460 toward the cap 1439 so that the first indicia area 1462 is positioned adjacent the transparent tube 1437 and is therefore visible to the user, as shown in Figures 14C and 14E. At the same time, the second indicia area 1464 is obscured by the non-transparent cap 1439 in the vacuum-off position. When the tip 1426 of the syringe 1400 is under vacuum, the vacuum indicator 1430 is in a vacuum-on position in which the vacuum pulls the flexible member 1434 into / toward the opening 1461, thereby pulling the indicator 1460 toward the opening 1461 against the biasing force of the biasing member 1466, such that the second indicator area 1464 is positioned adjacent the transparent tube 1437 and is therefore visible to the user, as shown in FIGS. 14D and 14F . At the same time, the first indicator area 1462 is obscured by the non-transparent base 1435 in the vacuum-on position. In this manner, the first and second indicator areas 1462, 1464 are configured to provide a visual indication to the user of whether the syringe 1400 (and the coupled assembly 700 of FIG. 7 ) is under vacuum.

[0074] 15A and 15B are isometric and side views of a syringe 1500 in accordance with an additional embodiment of the present technology. The syringe 1500 is in a depressed / advanced position in FIGS. 15A and 15B. Referring together to FIGS. 15A and 15B, in some embodiments, the syringe 1500 can be generally identical to the syringe 1400 (e.g., including the plunger 1410, barrels 1420, 1426, base 1440, and locking member 1450) described in detail above with reference to FIGS. 14A and 14B. However, in the embodiment shown, the syringe 1500 includes a different vacuum indicator 1530 formed on and / or coupled to the tip 1426.

[0075] 15C and 15D are enlarged side views of vacuum indicator 1530 in "vacuum off" and "vacuum on" positions, respectively, in accordance with an embodiment of the present technology. 15E and 15F are enlarged, partially see-through side views of vacuum indicator 1530 in vacuum off and vacuum on positions, respectively, in accordance with an embodiment of the present technology. 15G is an enlarged, cross-sectional side view of vacuum indicator 1530 in the vacuum off position, in accordance with an embodiment of the present technology. 15C and 15D ...G can include various features that are at least generally similar in structure and function to or identical in structure and function to corresponding features of vacuum indicator 1430, described in detail above with reference to FIGS. 14C-14G, and can operate in a manner generally similar or identical to vacuum indicator 1430.

[0076] 15E-15G , for example, the vacuum indicator 1530 can include a flexible member 1534 (e.g., a diaphragm, a rolling diaphragm) sealingly positioned over the opening 1461 in the tip 1426. The flexible member 1534 can be biased to a first (e.g., preconvoluted) position in a vacuum-off position and can be pulled downward toward the opening 1461 to a second position in a vacuum-on position. Referring to FIGS. 15C-15G , the vacuum indicator 1530 can further include (i) a non-transparent (e.g., opaque) base 1535 positioned around and / or coupled to the flexible member 1534, (ii) a transparent tube 1537 coupled to and extending from the base 1535, and (iii) a non-transparent cap 1539 coupled to and positioned over the tube 1537. The base 1535, the tube 1537, and / or the cap 1539 can be integrally formed or can be separate components coupled to one another. The vacuum indicator 1530 further includes an indicator 1560 positioned within the tube 1537 and the cap 1539. In the embodiment shown, the indicator 1560 includes a first indicator region or portion 1562 and a second indicator region or portion 1564, each having at least one distinct visual characteristic. For example, in some embodiments, the first indicator portion 1562 can be a first color (e.g., red) and the second indicator portion 1564 can be a different second color (e.g., green). In some embodiments, the second indicator portion 1564 is at least partially nested within the first indicator portion 1562 in the vacuum-off position (e.g., as best seen in FIG. 15G ). The first marking portion 1562 (e.g., its lower end portion) can be coupled to the flexible member 1534, while the second marking portion 1564 (e.g., its upper end portion) can be coupled to the cap 1539.

[0077] When the tip 1426 of the syringe 1500 is not under vacuum, the vacuum indicator 1530 is in a vacuum-off position, as shown in Figures 15C and 15E, where the flexible member 1534 is in the first position and biases the first indicator portion 1562 upward toward the cap 1539 so that the second indicator portion 1564 is positioned adjacent the transparent tube 1537 and is therefore visible to the user. At the same time, the first indicator portion 1562 at least partially surrounds the second indicator portion 1564 so that the second indicator portion 1564 is obscured in the vacuum-off position and is not visible to the user. When the tip 1426 of the syringe 1500 is under vacuum, the vacuum indicator 1530 is in a vacuum-on position in which the vacuum pulls the flexible member 1534 into / toward the opening 1461, thereby pulling the first indicator portion 1562 downward, away from the cap 1539 and the second indicator portion 1564, such that the second indicator portion 1564 is visible through the transparent tube 1537, as shown in FIGS. 15D and 15F . At the same time, the first indicator portion 1562 is obscured by the non-transparent base 1535 in the vacuum-on position. In this manner, the first and second indicator portions 1562, 1564 are configured to provide a visual indication to the user of whether the syringe 1500 (and the coupled assembly 700 of FIG. 7 ) is under vacuum.

[0078] In some embodiments, alternatively or in addition to biasing the first indicator portion 1562 to the vacuum-off position using the flexible member 1534, the vacuum indicator 1530 can include a biasing member configured to bias the first indicator portion 1562 to the vacuum-off position. For example, FIG. 16 is an enlarged side cross-sectional view of the vacuum indicator 1530 further including a biasing member 1666, such as a spring, operably coupled between the cap 1539 and the first indicator portion 1562, in accordance with an embodiment of the present technology. In the embodiment shown, the biasing member 1666 has an upper end portion 1667 (e.g., its spring mount) coupled to the cap 1539 and a lower end portion 1668 (e.g., its spring mount) coupled to the first indicator portion 1562. In some embodiments, the biasing member 1666 can extend at least partially through an internal channel 1669 of the second indicator portion 1564. When the tip 1426 of the syringe 1500 is not under vacuum, the biasing member 1666 can bias the first indicated portion 1562 toward the cap 1539 to a vacuum-off position. When the tip 1426 of the syringe 1500 is under vacuum, the flexible member 1534 can pull the first indicated portion 1562 against the biasing force of the biasing member 1666 toward the opening 1461 to a vacuum-on position.

[0079] IV. Further Examples The following examples are illustrative of various embodiments of the present technology. 1. A self-locking syringe, comprising: Barrel and a plunger slidably positioned within the barrel, the plunger being movable between a depressed position and a retracted position, the plunger including a locking feature; a locking plate coupled to the barrel and having an opening extending therethrough, the plunger being slidably positioned within the opening, the locking plate including a biasing member configured to bias the locking plate to a locked position; when the plunger is moved from the depressed position to the retracted position, the locking feature is configured to engage the locking plate and drive the locking plate away from the locked position, thereby allowing the locking feature to pass through the opening; The syringe, wherein after the locking feature passes through the opening, a biasing member is configured to drive the locking plate to a locked position to prevent movement of the plunger from the retracted position to the depressed position. 2. The syringe of example 1, wherein the locking feature includes a stop surface extending generally perpendicular to the longitudinal axis of the syringe, and wherein the locking plate is configured to engage the stop surface when (a) the locking plate is in the locked position and (b) the plunger is in the retracted position. 3. The syringe of example 1 or example 2, further comprising a button coupled to the locking plate, the button being operable to move the locking plate away from the locked position and allow movement of the plunger from the retracted position to the depressed position. 4. The syringe of any one of Examples 1 to 3, wherein the biasing member includes at least one of a spring and a living hinge. 5. The syringe of any one of Examples 1 to 3, wherein the biasing member is an arm hingedly connected to the locking plate. 6. The syringe of any one of Examples 1-5, wherein the locking feature is one of a plurality of locking features positioned along the longitudinal axis of the plunger. 7. When the plunger is moved from the depressed position to the retracted position, each of the locking features is configured to sequentially engage the locking plate to drive the locking plate away from the locked position, thereby allowing the locking features to pass through the opening; 7. The syringe of example 6, wherein the biasing member is configured to drive the locking plate to the locked position to prevent movement of the plunger from the retracted position to the depressed position after each of the locking features passes through the opening in sequence. 8. The syringe of example 6 or example 7, further comprising a locking mechanism configured to engage the locking plate and lock the locking plate in a position away from the locked position. 9. The syringe of any one of Examples 1 to 8, wherein the barrel has a volume of about 60 cc or more. 10. A self-locking syringe, a barrel including a flange; a plunger slidably positioned within the barrel, the plunger aligned along a longitudinal axis, the plunger movable along the longitudinal axis between a depressed position and a retracted position; a locking member coupled to the plunger, the locking member including a body and a first arm hingedly coupled to the body, the first arm configured to be biased at least partially outwardly, away from a longitudinal axis of the plunger, to a locked position; a syringe comprising: an actuator including a second arm, the actuator being movable between a first position and a second position, the second arm configured to engage the first arm in the second position to drive the first arm inwardly toward the longitudinal axis and away from the locked position. 11. The syringe of Example 10, wherein the first arm is configured to engage a flange of the barrel to prevent movement of the plunger from the retracted position to the depressed position when (a) the actuator is in the first position and (b) the plunger is in the retracted position. 12. The syringe of example 10 or example 11, wherein the locking member includes a third arm hingedly coupled to the body, the third arm configured to be biased at least partially outwardly, away from the longitudinal axis of the plunger, to the locked position; and the actuator includes a fourth arm configured to engage the third arm in the second position to drive the third arm inwardly, toward the longitudinal axis, away from the locked position. 13. The syringe of Example 12, wherein the first arm is configured to be biased at least partially outwardly away from the longitudinal axis in a first direction, and the third arm is configured to be biased at least partially outwardly away from the longitudinal axis in a second direction opposite the first direction. 14. The syringe of example 12 or example 13, wherein the first arm and the third arm have the same size and shape, and the second arm and the fourth arm have the same size and shape. 15. A syringe described in any one of Examples 12 to 14, wherein the third arm is configured to engage with a flange of the barrel to prevent movement of the plunger from the retracted position to the depressed position when (a) the actuator is in the first position and (b) the plunger is in the retracted position. 16. A clot treatment system comprising: A catheter, a pressure source configured to generate a vacuum pressure; a tubing subsystem configured to fluidly connect the catheter to a pressure source, the tubing subsystem including a vacuum indicator configured to provide an indication that the catheter is under vacuum pressure. 17. The clot treatment system of Example 16, wherein the tubing subsystem includes a window portion, and the vacuum indicator portion includes a flexible member positioned over the window portion, and the flexible member is configured to deform around the opening when the catheter is under vacuum pressure to provide an indication that the catheter is under vacuum pressure. 18. The clot treatment system of Example 17, comprising a housing, wherein the vacuum indicator is positioned around the flexible member and configured to prevent excessive deformation of the flexible member when the catheter is under positive pressure. 19. The clot treatment device of any one of Examples 16-18, wherein the pressure source is an auto-locking syringe. 20. the tubing subsystem includes a valve, a first tubing section, a fluid control device, and a second tubing subsystem; a valve fluidly connecting the catheter to the first tubing section; a first section of tubing fluidly connected between the valve and the fluid control device; a second tubing system fluidly connecting the fluid control device to a pressure source; 17. The clot treatment device of claim 16, wherein the vacuum indicator is fluidly connected between the valve and the fluid control device. 21. A syringe, a barrel having a tip, the tip including an opening; a plunger movable through the barrel to create a vacuum pressure within the barrel; a vacuum indicator positioned over the opening in the tip, the vacuum indicator including a transparent tube and an indicator movably positioned within the tube, the indicator including a first region having a first visual characteristic and a second region having a second visual characteristic different from the first visual characteristic; the first region is configured to be positioned adjacent to the tube when the barrel is not under vacuum pressure; The syringe, wherein the second region is configured to be positioned adjacent to the tube when the barrel is under vacuum pressure. 22. The vacuum indicator further includes an opaque cap over the tube, the indicator being movably positioned within the cap and the tube; the second region is configured to be positioned adjacent to the cap when the barrel is not under vacuum pressure; 22. The syringe of example embodiment 21, wherein the first region is configured to be positioned adjacent to the cap when the barrel is under vacuum pressure. 23. The syringe of Example 22, wherein the vacuum indicator further includes a biasing member coupled between the indicator and the cap, the biasing member configured to bias the indicator to position the first region adjacent to the tube when the barrel is not under vacuum pressure. 24. The syringe of any one of Examples 21-23, wherein the vacuum indicator further comprises a flexible member positioned over the opening in the tip and coupled to the indicator. 25. The syringe of example 24, wherein the flexible member is configured to deform around the opening when the catheter is under vacuum pressure. 26. A syringe as described in Example 24 or Example 25, wherein the vacuum indicator further includes an opaque cap over the tube, a first portion of the indicator being bonded to the flexible member, and a second portion of the indicator being bonded to the cap. 27. A syringe described in any one of Examples 21 to 26, wherein the vacuum indicator portion further includes a flexible member positioned over the opening in the tip portion and a biasing member, a first portion of the indicator portion being coupled to the biasing member and a second portion of the indicator portion being coupled to the flexible member. 28. A syringe described in any one of Examples 21 to 27, wherein the first and second portions of the indicator portion are movable relative to each other and the second indicator portion is at least partially nested within the first indicator portion.

[0080] V. Conclusion The above detailed description of embodiments of the present technology is not intended to be exhaustive or to limit the present technology to the precise form disclosed above. While specific embodiments and examples of the present technology have been described above for illustrative purposes, those skilled in the art will recognize that various equivalent modifications are possible within the scope of the present technology. For example, while steps are presented in a given order, alternative embodiments may perform steps in a different order. Various embodiments described herein may be combined to provide further embodiments.

[0081] From the foregoing, it will be understood that, although specific embodiments of the present technology have been described herein for illustrative purposes, well-known structures and functions have not been shown or described in detail in order to avoid unnecessarily obscuring the description of the embodiments of the present technology. Where the context permits, singular or plural terms may also include the plural or singular terms, respectively.

[0082] Furthermore, unless the word "or" is expressly limited in reference to a list of two or more items to mean only a single item exclusively from the other items, the use of "or" in such a list should be interpreted as including (a) any single item in the list, (b) all of the items in the list, or (c) any combination of the items in the list. Furthermore, the term "comprising" is used throughout to mean the inclusion of at least the recited features, but not the exclusion of any more of the same features and / or other features of additional types. While specific embodiments have been described herein for illustrative purposes, it will be understood that various modifications can be made without departing from the present technology. Furthermore, while advantages associated with some embodiments of the present technology have been described in the context of these embodiments, other embodiments may also exhibit such advantages, and not all embodiments necessarily exhibit such advantages to fall within the scope of the present technology. Thus, the present disclosure and related technology may encompass other embodiments not explicitly shown or described herein.

Claims

[Claim 1] The invention described in this specification.

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