Hemostat

Abstract

A hemostat for use by injured patients of different sizes includes a strap that can be wound around an injured limb to provide a desired hemostatic force, the strap being configured with a first portion and a second portion of different widths. In one embodiment, a gas flow control assembly of a pneumatic hemostat includes: a housing including a longitudinally movable force transmitting element and a gas reservoir; and a pivotable actuation handle wherein, when the actuation handle is pivotally moved about its axis of rotation, pressurized gas is expelled from the reservoir and then flows into the interior of the inflatable bandage to provide the hemostatic force. In other embodiments, the pneumatic hemostat includes one or more of a flow control unit, a manual pressure release activator, a puncture mitigation connection portion, and a strap configured with interconnected inner, outer, and intermediate sealant layers.

Description

[0001] Divisional application

[0002] This application is a divisional application of application number 201980086323.8, application date October 24, 2019, and titled “Hemostat”. Technical Field

[0003] The present invention relates to the field of pneumatic hemostats. In some embodiments, the present invention relates to a pneumatic hemostat for controlling bleeding suitable for use by medical personnel and inexperienced first responders unexpectedly placed in a pre-medical emergency situation. Background Art

[0004] A hemostat is a well-known device for stopping bleeding. Traditionally, a bandage (e.g., a bandage) is tightened by a makeshift tool such as tape to apply pressure to an artery, thereby stopping blood flow through a limb.

[0005] Other manually applied hemostats that use force-applying devices such as ratchets or capstans can stop blood loss from an injured arm within 20-80 seconds. However, because the depth of the femoral artery relative to the skin surface is greater than the depth of the brachial artery, and the size of the thigh is larger relative to the arm, a significantly larger force of about 300-600N is required and sustained for a longer period of time to suppress femoral artery bleeding. The actual force required to stop bleeding depends on the thickness of the limb, the depth of the artery within the limb, and the width of the bandage that transmits the applied force to the injured artery. In order to reduce the amount of manually applied force required to stop bleeding, the width of the bandage is usually limited, which can easily lead to soft tissue, muscle, nerve and bone damage in the injured limb, especially for narrower bandages of about 2.5 cm in size, which can cut the skin if too much force is applied.

[0006] Therefore, it is desirable to provide a pneumatic hemostat with a wider bandage, which can evenly apply pressure to the injured limb even when a sufficiently large hemostatic force is applied, thereby not damaging soft tissue.

[0007] Pneumatic hemostats are commonly used in limb surgery to achieve a nearly bloodless procedure while being able to apply a relatively large hemostatic force to the injured limb. Such pneumatic hemostats in the prior art include an inflatable cuff, which is a bandage constructed with a rubber air bag located within a plastic or fabric outer cover. A connecting tube is used to connect the cuff to a pressure device, which includes an air compressor, a pressure setting button, a pressure setting digital display, and a timer. The pressure device is powered by electricity and is therefore connected to a wall outlet, so the devices associated with these prior art pneumatic hemostats are fixed and are not practical for medical personnel who need to treat wounded patients in an external location. In addition, the wide bandages used in hospital environments are approximately 20 cm wide and are relatively large in size, making them inconvenient to transport in a small bag for use by medical personnel.

[0008] Other prior art pneumatic hemostats have disadvantages including a lack of protection for the pressurized gas source required to inflate the bandage, making it unsuitable for use in a battlefield environment, and the inability to use the pressurized gas source multiple times for hemostatic procedures.

[0009] When a hemostat is used for a long time, the injured patient's limb tissue is susceptible to ischemia due to the cessation of blood flow distal to the hemostat. The extent of ischemic changes depends on the duration of limb obstruction. These symptoms can be reversible if the pressure applied by the hemostat is short-term, less than two hours, or is periodically released every few minutes while allowing bleeding to resume. However, because excessive blood loss that may lead to death may occur, if a pneumatic hemostat is used, medical personnel are discouraged from releasing pressure, such as by reducing the pressure in the bandage by deflating it, before sending the patient to the hospital. After the pneumatic hemostat is deflated, products such as excessive acid, lactic acid, toxic metabolites and oxygen free radicals are introduced into the blood system and cause complications such as systemic metabolic changes and reperfusion syndrome that may lead to cardiac arrest.

[0010] Furthermore, if the pneumatic hemostat is temporarily deflated before medical transport, the stored pressurized gas will be exhausted while the interior of the bandage is exposed to atmospheric air, thereby rendering the pneumatic hemostat unusable after deflation.

[0011] The object of the present invention is to provide a pneumatic hemostat for use by medical personnel and inexperienced emergency personnel in emergency situations before being sent to a doctor, so as to inflate a bandage that applies a hemostatic force to a predetermined pressure.

[0012] Another object of the present invention is to provide a pneumatic hemostat that will not harm adult and pediatric injured patients when using an inflatable cuff.

[0013] Another object of the present invention is to provide a compact, reliable and user-friendly pneumatic hemostat that is easily deployed in external locations.

[0014] It is a further object of the present invention to provide a pneumatic hemostat suitable for use by medical personnel that can temporarily deflate the bandage if necessary.

[0015] Another object of the present invention is to provide a pneumatic hemostat having a flow control unit that can be used for multiple hemostatic operations.

[0016] It is yet another object of the present invention to provide a pneumatic hemostat that reduces the consumption of pressurized gas for each hemostatic procedure.

[0017] Other objects and advantages of the present invention will become apparent as the description proceeds. Summary of the invention

[0018] A hemostat for use with injured patients of different sizes comprises a bandage that can be wrapped around an injured limb to provide a desired hemostatic force, the bandage being constructed with a first portion and a second portion having different widths, wherein the second portion is a pressure applying portion that is significantly narrower and longer than the first portion, and the first portion is suitable for transmitting a much smaller hemostatic force to the injured limb than the hemostatic force transmitted by the second portion.

[0019] A pneumatic hemostat comprises an inflatable bandage adapted to receive pressurized gas and be wrapped around an injured limb to provide a desired hemostatic force.

[0020] In one embodiment, the pneumatic hemostat further comprises a tightening device adapted to receive a free end of the bandage so that the free end can move freely within the tightening device until the free end is clamped when the bandage is sufficiently tightened to transmit the hemostatic force. The tightening device may comprise a housing member and a rocker, the rocker being rotatably mounted on and within the housing member via a longitudinally extending axis, the rocker being configured to angularly displace about the axis in response to a force applied to the rocker by the injured limb when the bandage is sufficiently tightened until a surface of the rocker is clamped with a clamping edge of the housing member, while the bandage is disposed between the surface of the rocker and the clamping edge.

[0021] In one aspect, the pneumatic hemostat further comprises a sealing element, wherein the clamping force applied to the sealing element by the rocker surface and the clamping edge prevents pressurized gas from flowing from the pressure-applying portion of the bandage wrapped around the injured limb to the free end, thereby making the free end of the bandage significantly narrower than the pressure-applying portion.

[0022] In one aspect, the sealing element is disposed inside a bandage, the bandage being constructed with an inner layer, an outer layer, and a middle sealant layer connected to each other.

[0023] In one aspect, the sealing element is external to the strap.

[0024] A user-friendly gas flow control assembly of a pneumatic hemostat comprises: a housing including a shell, a longitudinally movable force transfer element and an air outlet, the housing being connectable to a gas cartridge filled with pressurized gas and usually sealed by a blocking element; a pivotable actuating handle configured with a wide-area, generally flat user-operable surface; and a structure provided with the housing, cooperating with the actuating handle to define a rotational axis of the actuating handle, wherein when the actuating handle is pivotally moved about its rotational axis, an actuating force is transmitted, the actuating force drivingly contacts the force transfer element to forcefully contact and open at least a portion of the blocking element, thereby allowing pressurized gas to be discharged from the gas cartridge and flow through the air outlet to the interior of an inflatable bandage, which can be wrapped around an injured limb to provide the desired hemostatic force.

[0025] In one aspect, the obstructing element is a pierceable cap and the force transmitting element is a piercing pin terminating in a pointed tip drivable to an inwardly displaced position in which the pointed tip pierces the pierceable cap.

[0026] In one aspect, the force transfer element is an actuating piston configured to cooperate with a valve stem associated with the gas cartridge.

[0027] In one aspect, the structure provided with the housing and cooperating with the actuating handle to define the axis of rotation is a transversely extending beam rotatably mounted in a corresponding seat provided with the housing to define the axis of rotation of the actuating handle. A cam fixedly connected to the beam is drivably adjacent to the force transmitting element.

[0028] A flow control unit (e.g., a pressure regulating unit) comprises: a shell member configured with an inlet and an inner cavity for receiving pressurized gas as needed; a hollow tube with an outer diameter less than 2.5 mm, which is connected to the inlet fluid; a piston with a central opening, which is connected to the tube and has an outer diameter significantly larger than the outer diameter of the tube, and the piston can move axially and sealingly in the inner cavity to define a supply chamber connected to the atmospheric air fluid at the distal end of the piston and a regulating chamber connected to the inlet fluid via the tube at the proximal end of the piston; and a fixed sealing element, wherein, after the pressurized gas flows into the regulating chamber, the piston is moved distally by the pressure difference between the pressure in the regulating chamber and the pressure in the supply chamber until the distal end of the tube is blocked by the sealing element to prevent additional inflow of pressurized gas.

[0029] A pneumatic hemostat comprises: an inflatable bandage and a pressure regulating unit. The inflatable bandage can be wrapped around an injured limb to provide a desired hemostatic force. The pressure regulating unit is configured with: an inlet for receiving pressurized gas as required; a piston that can be axially and sealingly moved in an inner cavity to define a supply chamber in fluid communication with atmospheric air at a distal end of the piston and a regulating chamber in fluid communication with the inlet and the inner part of the bandage at a proximal end of the piston; and a manual pressure release actuator that, when moved, provides a gap in fluid communication with the regulating chamber and the atmospheric air to selectively reduce the pressure of the fluid inside the bandage while preventing the pressurized gas from additionally flowing into the regulating chamber.

[0030] A puncture relief connection portion for connecting an inflatable strap to a housing of a gas flow control assembly, comprising: a flexible air inlet that protrudes through an outer layer of the inflatable strap and has a central channel that is in fluid communication with the interior of the strap, wherein the air inlet is connectable to an exhaust port of the gas flow control assembly through which pressurized gas for inflating the strap can be exhausted; and a plurality of fasteners that protrude from the outer layer of the strap and are separate from the air inlet, wherein each of the fasteners is connectable to a corresponding fixing element that is associated with the housing of the gas flow control assembly.

[0031] In one aspect, the plurality of fasteners are integrally formed with a rigid plate positioned within the strap interior and attached to the outer strap layer and formed with an aperture through which the air inlet protrudes.

[0032] In one aspect, the rigid plate is attached to a semi-rigid sealing layer adapted to provide additional protection against egress of pressurized gas from the connection portion, to which the mounting elements of the air inlet are attached.

[0033] As mentioned herein, "longitudinal" refers to the direction along the axis parallel to the tubular gas cartridge when the tubular gas cartridge is coupled to the piercing unit housing. "Transverse" refers to a direction generally perpendicular to the longitudinal direction. "Horizontal" refers to a direction at an angle to the longitudinal direction, which is not necessarily transverse. "Proximal" refers to the direction toward the user-accessible element of the hemostat, such as the unattached edge of a manual pressure release trigger or an actuating handle away from its axis of rotation. "Distal" refers to the direction opposite to the proximal direction. Other directional terms, such as "top", "above", and "below" refer to the direction when the hemostat is set on the top of a horizontal surface, but the hemostat can be set in any other desired direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In the attached picture:

[0035] Figure 1 is a perspective view from the top of an embodiment of a pneumatic hemostat, showing the tightening device in an open position and with the inflatable cuff only partially shown;

[0036] Figure 2 yes Figure 1 Exploded view of the hemostat;

[0037] Figure 3 It is available with Figure 1 A perspective view from the top of an inflatable bandage used in conjunction with a hemostat, the inflatable bandage being shown in a flattened state;

[0038] Figure 4 yes Figure 1a perspective view of the hemostat from the bottom, shown with the tightening device in an open position and the inflatable strap removed;

[0039] Figure 5 yes Figure 1 a perspective view from the bottom of the hemostat of , shown with the tightening device in the closed pivot position and the inflatable strap removed;

[0040] Figure 6 yes Figure 1 a perspective view from the top of the hemostat of , shown with the upper housing of the gas flow control assembly removed and the gas cartridge partially removed to show the fasteners connecting the inflatable strap to the lower housing;

[0041] Figure 7 Cut along the mid-plane through the gas flow control assembly when deployed during a hemostasis procedure Figure 1 The hemostat, the two separated parts of the inflated bandage and the cross-section of the injured limb;

[0042] Figure 8 is a cross-sectional view of an injured limb cut along the front, showing Figure 1 The hemostat, when deployed during a hemostatic procedure, causes the inflated band to be wrapped around the limb and disposed in a clamping relationship relative to the constricting device;

[0043] Fig. 9 is with Figure 1 A cross-sectional view of a tightening device used in conjunction with a hemostat, showing an inflatable band being fed into the tightening device;

[0044] Fig.10 is a plan view of components associated with an airflow control assembly, shown with the components removed from a housing;

[0045] Fig.11 yes Fig.10 A cross-sectional view of a component cut along a horizontal plane;

[0046] Fig.12 is a horizontal cross-sectional view of another embodiment of a gas flow control assembly, not showing a piercing pin and a tube of a pressure regulating unit;

[0047] Fig.13 is and Figure 1 A perspective view from the top of the actuation handle of the hemostat with the housing of the airflow control assembly separated;

[0048] Fig.14 yes Figure 1 a perspective view from the top of the hemostat of , shown with the actuation handle in a pivoted position;

[0049] Fig.15 is through and Figure 1 a longitudinal cross-sectional view of a portion of a gas flow control assembly for use in conjunction with a hemostat showing the actuation handle in a non-pivoted position with a cam associated therewith drivably proximate a head element of a piercing pin;

[0050] Fig.16 is through and Figure 1 a longitudinal cross-sectional view of a portion of a gas flow control assembly cut away in conjunction with a hemostat showing the actuation handle in a pivoted position;

[0051] Fig.17 yes Fig.11 an enlarged view of a portion of the pressure regulating unit showing details;

[0052] Fig.18 It is available with Fig.17 A perspective view from the front of a tube used in conjunction with a pressure regulating unit;

[0053] Fig.19 is through and Figure 1 A longitudinal cross-sectional view of a portion of a gas flow control assembly for use in conjunction with a hemostat showing a manual pressure release actuator set to a retracted proximal position;

[0054] Fig. 20 is through and Figure 1 A longitudinal cross-sectional view of a portion of a gas flow control assembly for use in conjunction with a hemostat, showing a manual pressure release actuator set to an advanced distal position;

[0055] Fig.21 is a perspective view from the top of another embodiment of a pneumatic hemostat shown deployed on a schematically illustrated injured limb and with a tightening device coupled to a gas flow control assembly;

[0056] Fig. 22 yes Fig.21 a perspective view from the top of the hemostat of FIG. 1 , shown deployed on a schematically illustrated injured limb and with the tightening device separated from the gas flow control assembly;

[0057] Fig.23 is a perspective view from the top of another embodiment of a pneumatic hemostat shown deployed on a schematically illustrated injured limb and with a tightening device coupled to a gas flow control assembly;

[0058] Fig.24 is a perspective view from the side of another embodiment of a pneumatic hemostat pre-delivered with an inflatable band;

[0059] Fig.25 yes Fig.24A top view of the hemostat shown with the upper housing of the gas flow control assembly removed;

[0060] Fig.26 is with Fig.24 A perspective view from the top of a portion of an inflatable bandage used in conjunction with a hemostat;

[0061] Fig.27A yes Fig.26 A top view of the entire strap, shown in a flat state;

[0062] Fig.27B yes Fig.27A A side view of the strap after inflation;

[0063] Fig.27C yes Fig.27A A perspective view of a strap connected to a gas flow control assembly and with its free end pre-fed into a tightening device;

[0064] Fig.28A yes Fig.26 A cross-sectional view of a wider connecting portion;

[0065] Fig.28B It is used to manufacture Fig.28A An exploded perspective view of the components of the connecting portion;

[0066] Fig.28C yes Fig.28B A perspective view of the parts after they are attached together;

[0067] Fig.28D yes Fig.28C An exploded perspective view of the attachment member of the inflatable strap under the outer surface of the inflatable strap before being attached to the outer surface of the inflatable strap;

[0068] Fig.29 yes Fig.24 a perspective view from the side of the gas flow control assembly, wherein the gas flow control assembly is separated from the tightening device and the actuation handle is set to a pivoted position;

[0069] Fig.30 yes Fig.24 A cross-sectional view of a gas flow control assembly of , wherein the actuation handle is in a non-pivoted position and the actuation piston is disposed in a non-actuated position;

[0070] Fig.31 yes Fig.24 A cross-sectional view of a gas flow control assembly of , wherein the actuation handle is in a pivoted position and the actuation piston is disposed in an actuated position;

[0071] Fig.32A yes Fig.24A cross-sectional view of a portion of the tightening device showing the rocker in a non-pivoted position;

[0072] Fig.32B yes Fig.24 a cross-sectional view of a hemostat showing the rocker in a pivoted position and a perspective view showing a circumferentially extending strap external to the gas flow control assembly and the tightening device to illustrate the weld line;

[0073] Fig.33 yes Fig.24 A perspective view of a hemostat from the side and bottom with the strap removed showing an embodiment of a tightening device;

[0074] Fig.34 yes Fig.24 A perspective view of a hemostat from the side with the band removed showing another embodiment of a tightening device; and

[0075] Fig.35 yes Fig.24 A perspective view of a hemostat from the side and bottom with the straps removed illustrates another embodiment of a tightening device. DETAILED DESCRIPTION

[0076] The compact pneumatic hemostat of the present invention is primarily, but not necessarily, used in emergency situations, such as after a motor vehicle crash, explosion, and stabbing accident, or on the battlefield, to try to stop limb bleeding and death from excessive blood loss. After the bandage is inflated to a predetermined pressure, pressure is applied circumferentially around a portion of the injured limb, thereby temporarily occluding the blood vessel to which the pressure is applied.

[0077] Due to its user-friendly construction, the hemostat is easily actuated by all users, including medical personnel, inexperienced first aid personnel accidentally placed in an emergency situation, and even injured patients can actuate the hemostat to start a hemostasis operation, and the bandage is easy to wrap around the injured limb and tighten.

[0078] As will be described below, the unique construction of the hemostat greatly reduces complications typically associated with prolonged use of the hemostat, as well as damage to the skin and underlying tissue caused by excessive pressure applied to a pediatric patient.

[0079] Since the pressurized gas used by the pneumatic hemostat is supplied internally within the housing of the gas flow control assembly, typically via a gas cartridge, rather than being supplied externally to the housing via an electrically operated gas delivery device as practiced in the prior art, the compact hemostat of the present invention does not have any electrical or electronic components, and can thus be advantageously used in wet or muddy environments. Of course, in some embodiments, a well-sealed electronic module may be added, such as an electronic module including a GPS component for locating the subject or a sensor for determining some real-time physiological characteristics of the subject, similar to the electronic module provided to divers.

[0080] Figure 1 and Figure 2 An embodiment of a pneumatic hemostat 40 is shown. The pneumatic hemostat 40 includes a gas flow control assembly 43, a tightening device 48 pivotally connected to the gas flow control assembly 43, and an inflatable strap 49 connected to the gas flow control assembly 43 and selectively tightened by the tightening device 48.

[0081] The inflatable strap 49 can be constructed of three layers 13-15 of substantially equal length and width. The inner layer 15 is made of a flexible tear-resistant material. The outer layer 13, which is exposed to the underlying terrain that typically has sharp objects such as thorns and broken glass, is made of a flexible and puncture-resistant material (such as silicone rubber or a fabric made of a flexible material such as nylon or polyester fibers) and is sealed with a layer of puncture-resistant material such as polyurethane. The middle layer 14 is made of a sealant such as polyurethane.

[0082] The gas flow control assembly 43 is constructed with a housing, for example, having an upper portion 2 and a lower portion 38 according to the orientation shown to form a curved proximal user accessible surface. The upper housing portion 2 and the lower housing portion 38 can be coupled together by a plurality of spaced fasteners 9, such as threaded fasteners. Two longitudinally spaced arms 51 and 52 can extend downwardly from the same side of the lower housing portion 38, each arm terminating in a corresponding arc-shaped protruding seat 54. The two seats 54 face each other.

[0083] A replaceable gas cartridge 21, a piercing unit housing 18, a pressure regulating unit 24, and a manual pressure release actuator 4 are mounted within the gas flow control assembly 43. The metal cover that normally seals the gas cartridge 21 is pierced in the piercing unit housing 18 to allow pressurized gas (e.g., carbon dioxide or nitrogen) to be discharged from the gas cartridge. The pressure regulating unit 24 is used to control the pressure of the gas discharged into the interior of the inflatable strap 49. The manual pressure release actuator 24 is operably connected to the pressure regulating unit 24 so as to selectively deflate the strap 49 while ensuring that the remaining pressurized gas in the gas cartridge 51 is not discharged. The manual pressure release actuator 4 may protrude from the curved proximal surface of the housing.

[0084] The gas cartridge 21 can be supplied with carbon dioxide, nitrogen, inert gas or refrigerant gas. The gas can be replaced after removing the cartridge cover 5 (pressurized to 70-170 bar at 60° C. and pressurized to about 20 bar at -10° C.). The cover 5 can be, for example, about half the width of the housing, about one quarter the length of the housing, and about equal to the total thickness of the upper housing part 2 and the lower housing part 38 in height, or any suitable size. The cartridge cover 5 can be removably fixed to the housing by one or more magnets 6 attached to the lower housing part 38.

[0085] Alternatively, the gas flow control assembly 43 may be configured without a pressure regulating unit or without a piercing unit housing. When the gas flow control assembly is configured without a piercing unit housing, another type of force transmitting element (e.g. Fig.30 Element 472 shown in ) can be selectively driven to forcefully contact and open at least a portion of the blocking element that normally seals the gas cartridge 21 so that pressurized gas flows from the gas cartridge into the interior of the inflatable band 49.

[0086] Alternatively, the gas flow control assembly is provided with a non-replaceable gas cartridge and accordingly is constructed without a cartridge cap.

[0087] A thin and wide area actuation handle 3 for inflating the strap 49 is pivotally connected to the distal end area of ​​the housing of the gas flow control assembly 43. When the width of the actuation handle 3 is greater than 60% of the width of the gas flow control assembly 43, the actuation handle 3 has a user-friendly wide area. The actuation handle 3 is generally covered on a groove 39, which is formed in the upper housing portion 2 by a small gap sufficient for a portion of a finger (e.g., 0.5 cm) to be inserted and pivotally raise the handle 3. The thickness of the actuation handle 3 is generally uniform; however, the thickness can be gradually increased, for example, from a thickness of 1 mm in the finger contact area to maximize the finger gap, gradually increasing to a thickness of 3 mm in the pivot axis area, thereby increasing the overall structural strength of the actuation handle. The actuation handle 3 is generally flat to reduce the amount of material required, however it can be slightly curved while having a fairly high structural strength to be able to transmit the actuation force, as will be described below.

[0088] In one embodiment, the groove 39 extends distally to a timing device 34, such as a digital timing device, adapted to indicate the start of a hemostasis operation, housed in the half of the upper housing portion 2 not occupied by the cartridge cover 5, distal to the curved proximal surface.

[0089] The tightening device 48 for clamping the inflatable strap 49 when it is sufficiently tightened comprises a housing member 10 and a rocker 11 rotatably mounted on and in the housing member 10 via an axis 12 .

[0090] The shell member 10 has a thickened end wall 56 as well as an outer wall 58 and two longitudinally spaced side walls 57. The end wall 56 may be flat and rectangular; the side walls 57 extend downwardly from the upper wall 56 to a height below the lower surface of the end wall 56 relative to the orientation shown, so as to define a projection 59. The lower edge 66 of the outer wall 58 constitutes a clamping edge. A hole 62 is drilled in each side wall 57, so that the two holes 62 are aligned. A bending element 64 extends downwardly from the inner edge 63 of the upper wall 56, terminating in two hinge elements 67 extending longitudinally in opposite directions, which are housed in corresponding seats 54, so that the shell member 10 can rotate around an axis coinciding with the seat 54.

[0091] The rocker 11 has a flat surface 71 which may be rectangular, and two longitudinally spaced side walls 74 which extend upward from the surface 71 and may be curved upward. Each side wall 74 may have a short portion 77 which protrudes laterally from the curved portion, and the upper edge of the short portion 77 is coplanar with the surface 71. A short inner leg 81 and a short outer leg 83 extending longitudinally between the two side walls 74 may extend downward from the surface 71. The longitudinal spacing between the side walls 74 is less than the longitudinal spacing between the side walls 57 of the housing member 10. In each side wall 74, a hole 76 is preferably drilled in an area closer to the corresponding short portion 77 so that the two holes 76 are aligned. The shaft 12 is adapted to be received in the holes 62 and 76 so that the rocker 11 can swing around it. An outer wall 79 (i.e., facing away from the arms 51 and 52) extends longitudinally between the two short portions 77 and extends upward from the surface 71 to a height significantly less than the height of the side walls 74.

[0092] Figure 3 A top view of an inflatable cuff 49 when flat is shown. The cuff 49 may be constructed with two integral portions 44 and 46 of different widths. The portion 44 having a uniform width A (e.g., 50 mm) is elongated and suitable for wrapping around an injured limb to apply circumferential pressure to stop bleeding. The portion 46 has a maximum width B (e.g., 100 mm) that is greater than the width A. The portion 46 may be connected to the housing of the gas flow control assembly to increase the strength of the connection and may be constructed with a curved (e.g., elliptical) circumference. By providing a cuff with a relatively narrow pressure-applying portion, wherein the cuff 49 is free to move until constrained by a tightening device, the tightening device may also be advantageously narrow to make the device compact. The short end 45 of the cuff 45 opposite the connecting portion 46 is included in the free end of the cuff that is pulled during the tightening operation, and the width of the short end 45 may be slightly greater than A, e.g., 60 mm, to prevent the free end from retracting through the tightening device in the opposite direction.

[0093] In contrast to manually applied hemostats, which are narrow and whose bandages are usually a maximum of 5 cm wide due to the difficulty in applying the required hemostatic force, the pneumatic hemostats of the present invention are able to achieve sufficiently high pressures to apply hemostatic force to even limbs of large diameter. The bandage 49 is constructed with two integral portions 44 and 46 of different widths, and the hemostatic force is not entirely transmitted by the relatively narrow portion 44, which has significant clinical advantages. Wrapping a relatively wide bandage portion 46 (e.g., 15 cm) around a limb or at least a large portion of the limb evenly distributes the pressure applied to the surface of the limb and helps reduce pain and localized damage, which is very important for subjects with smaller limb diameters, such as pediatric patients. At the same time, a greater hemostatic force can be transmitted to adult patients with larger diameter limbs via the longer and narrower portion 44 without causing excessive pain and damage to the tissue.

[0094] In one embodiment, the two portions 44 and 46 are made of different materials with different degrees of flexibility. Therefore, the relative widths of portions 44 and 46 can change after the strap 49 is inflated. For example, portions 44 and 46 can have the same width before the strap is inflated; and after inflation, portion 44 becomes narrower and longer than portion 46.

[0095] It will be appreciated that the inflatable straps may be of uniform width.

[0096] In one embodiment, the strap having portions 44 and 46 of different widths may be non-inflatable. Portions 44 and 46 may be integrally formed with the non-inflatable strap, or alternatively, may be connected together, for example, detachably connected together, by various means known to those skilled in the art, such as bonding, sewing, welding, buttons, and Velcro.

[0097] like Figure 7 As shown, in addition to the outer layer 13, the middle sealant layer 14 and the inner layer 15 of the inflatable band, the connecting portion 46 is also provided with a relatively rigid attachment plate 61 adapted to be attached to the housing of the gas flow control assembly. The inner layer 15 is adapted to be in contact with the injured limb 35. The inner attachment plate 61 may be made of a relatively rigid plastic such as polypropylene or high-density polyethylene and is connected between the outer layer 13 and the sealant layer 14, for example, by welding. The three layers 13-15 may be welded together by a welding line 17, which extends longitudinally along the entire corresponding lateral edges of the inflatable band including the pressure applying portion 44 and the connecting portion 46.

[0098] like Figure 3As further shown, a plurality of separate snaps 65 or any other suitable type of fasteners (e.g., screws or clips) connected to the attachment plate protrude outwardly from the outer strap layer within the connecting portion 46. A tubular port 73 also protrudes outwardly from the outer strap layer for allowing pressurized gas to pass therethrough into the interior of the strap, and is generally centrally located relative to the plurality of fasteners 65.

[0099] Figure 4 and Figure 5 The hemostat 40 is shown from below when the tightening device 48 is set to an open position suitable for cooperating in performing a hemostatic operation and when it is set to a closed pivot position suitable for compact storage in a small bag ready for deployment in an emergency to help an injured patient. When the tightening device 48 is in the pivot position, the hinge element rotates approximately 180 degrees until the end wall 56 of the shell member is generally parallel to the lower surface 41 of the housing of the gas flow control component 43.

[0100] When the strap is non-inflatable, the small component can be fixed to the strap instead of the housing of the gas flow control assembly, and the arms 51 and 52 ( Figure 2 ) extends downward from the widget.

[0101] Figure 3 The strap 49 shown, after being wrapped, for example, may also be compactly stored in the same or a different pouch as the pivoting tightening device and gas flow control assembly.

[0102] like Figure 4 and Figure 6 As shown, the partially shown inflatable strap connection portion 46 is adjacent to the housing lower surface 41 by a plurality of snaps 65 which, when coupled to the piercing unit housing 18, are attached to a portion of the lower housing portion 38 located below the partially shown gas cartridge 21 .

[0103] Figure 4 , Figure 6 , Figure 7 and Fig.17 Some elements are shown that enable pressurized gas to flow into the interior 53 of the inflatable cuff 49. The flow of pressurized gas exhausted from the gas cartridge is directed to the interior 53 of the inflatable cuff through a centrally drilled port 73. The port 73 may be part of an element that can be coupled (e.g., removably coupled) to the gas flow control assembly 43 prior to performing a hemostatic procedure. Such an element may include an integral abutment 78 having a diameter or maximum width that is significantly larger than the port 73, and the tubular port 73 may be factory-secured to the attachment plate 61 via holes formed in the attachment plate 61 and the outer layer 13 and the middle layer 14 of the inflatable cuff, so that the abutment 78 is in a compressed relationship with the attachment plate 61.

[0104] Port 73 may be coupled to pressure regulating unit 24 via a tapered fitting 117 that extends downwardly from discharge conduit 114 of the pressure regulating unit by a simple squeezing action transmitted by coupling portion 46. When coupling portion 46 is attached to the housing bottom surface, pressurized gas exhausted from the gas cartridge will be directed to interior 53 of the inflatable strap via tube 26 of pressure regulating unit 24, discharge conduit 114, fitting 117, and port 73.

[0105] When pressurized gas is introduced into the common interior 53 of the pressure applying portion 44 and the coupling portion 46 , the inner layer 15 is separated from the intermediate sealing layer 14 as the pressure within the interior 53 increases.

[0106] Alternatively, one can use Fig.28A -Connection portion 452 shown in -D.

[0107] Figure 8 The pneumatic hemostat 40 is shown deployed during a hemostatic procedure. To ensure a rapid hemostatic procedure, the free end 44' of the band is pre-fed into a tightening device 48 when the hemostat is stored. In an emergency situation, the hemostat 40 is first removed from its bag and the tightening device 48 is placed on a selected area of ​​the injured limb 35 relative to the wound site. The pressure applying portion 44 is then wrapped around the limb 35 until the connecting portion 46 is attached to the gas flow control assembly housing 38, while the connecting portion 46 remains adjacent to the limb 35. By freely pulling the free end 44' of the band with a force T in a direction away from the tightening device 48, the pressure applying portion 44 is sufficiently tightened to enable a subsequent hemostatic procedure to be performed after the pressurized gas begins to be discharged from the gas cartridge.

[0108] like Fig. 9 As shown, when the hemostat is deployed, when the strap 49 is fed into the tightening device 48, for example, at the factory or by a medical professional, the strap 49 is positioned in active contact with the engageable strap upper surface 71 of the rocker 11 and below the shaft 12. When the strap 49 is wrapped around the injured limb and fully tightened, the limb applies a force to the inner wall 75 of each side wall of the rocker 11. This applied force causes the rocker 11 to rotate in a counterclockwise direction about the shaft 12 according to the orientation shown until the outer rocker wall 79 forms a clamping relationship with the clamping edge 66 of the outer wall 58 of the shell member 10, and the strap 49 is disposed between the outer rocker wall 79 and the shell member outer wall 58. Angular displacement of the rocker 11 can also be facilitated by spacing the shaft 12 from the vertical centerline of each side wall 74 to provide eccentric movement. In this clamping relationship, the free end of the strap 49 can no longer be pulled freely, but is clamped.

[0109] The manual pressure release actuator 4 can be used to release the band from the clamping edge 66 by reducing the pressure inside the band and making it free to move again, or to gradually release the pressure before removing the hemostat, the operation of which will be described below.

[0110] Refer again Figure 8 The clamping relationship established between the outer rocker wall and the outer shell member wall also advantageously enables the free end 44' of the bandage to be much narrower than the pressure-applying portion 44 of the bandage. When pressurized gas of a predetermined pressure is introduced into the interior of the bandage, the bandage is inflated, thereby applying a radial hemostatic force S to the limb 35. When there is no tightening device 48 to cooperate, the inflated free end 44 with a length of about 30 cm is likely to cause trouble to the injured patient and the medical staff trying to help the patient, and sometimes even cause harm to them. When the clamping relationship is established at the clamping edge, the outer rocker wall and the outer shell member wall both apply a clamping force to the middle sealant layer of the bandage, thereby preventing the pressurized gas from passing over the clamping edge from the pressure-applying portion 44 to the free end 44'. The middle sealant layer close to the outer layer also helps prevent the pressurized gas from leaking outward from the inside of the bandage to the atmosphere.

[0111] Now refer to Figure 10-Figure 16 , shows a device adapted to cooperate with the piercing unit housing 18 to start the discharge of pressurized gas from the gas cartridge 21. The discharged gas flows from the piercing unit housing 18 to the pressure regulating unit 24 via the interconnection structure 8.

[0112] like Fig.10 and Fig.11 As shown, the piercing pin 19 generally protrudes outwardly from the piercing unit housing 18 when in the retracted position and can then move axially in a hole 82 formed on the piercing unit housing 18.

[0113] The piercing pin 19 is configured with an elongated shaft 87 terminating in a pointed tip 88 adapted to pierce the metal cap 37 of the gas cartridge 21 after the metal cap 37 has been substantially fully inserted into the piercing unit housing 18 via the threaded engagement 36 through an opening at the end of the piercing unit housing 18 opposite the piercing pin 19. The piercing pin 19 also has a large-sized head element 89 that, when the actuating handle applies a driving force to the head element 89, contacts the head element 89 and moves the head element 8 to an inwardly moved position. Moving the piercing pin 19 to the inwardly moved position with a force sufficient to cause the pointed tip 88 to pierce the metal cap 37, thereby causing the pressurized gas to be discharged from the gas cartridge 21. The discharged gas flows through the aperture 82 and the conduit 93 in fluid communication with the aperture 82, and flows from the piercing unit housing 18 to the housing 96 of the pressure regulating unit 24 through the interconnection structure 8. Sealing elements 22 and 23, such as O-rings, respectively located at both ends of the hole 82 prevent gas leakage.

[0114] When the head element 89 is set to the moving position, the head element 89 will limit the inward movement of the piercing pin 19 when contacting the surface of the piercing unit housing 18. When the force applied to the actuating handle is released, the piercing pin 19 can return to the retracted position by the pressure of the exhaust gas.

[0115] Alternatively, if Fig.12 As shown, after the force applied by the actuating handle has been released, the coil spring 20 (partially removed for clarity) around the piercing pin shaft is biased to facilitate the piercing pin to return to the retracted position. The coil spring 20 can be compressed by the head element 89, for example, simultaneously with the pivoting of the actuating handle and the piercing of the metal cover. When the force applied to the actuating handle is released, the stored spring energy is also released, causing the piercing pin to retract. The retracted head element can therefore apply a force that causes the actuating handle to pivot in the opposite direction to a non-pivoted position.

[0116] Fig.13 The user-friendly actuation handle 3 is shown separated from the housing of the gas flow control assembly. The actuation handle 3 includes a thin and relatively wide, generally flat user operable surface 101, which may have a curved distal edge to avoid interference with the housing when pivoted. The user operable surface 101 is provided with two opposing side walls 103, which are adapted to abut against corresponding upper housing portion side walls when the actuation handle 3 is in a non-pivoted position and extend along the entire length of the surface 101, or as Figure 1 and Fig.14 As shown, the arc-shaped extension 104 extends only along the distal end of the surface 101. The arc-shaped extension 104 is located below the distal region of the corresponding side wall and is bent inwardly relative to the distal region of the corresponding side wall at a portion thereof. A flat surface 107 substantially perpendicular to the user-operable surface 101 contacts inwardly relative to the distalmost portion of the corresponding pair of side walls 103 and the extension 104. The transversely extending beam 109 extends between the two flat surfaces 107 and has a curved surface that is rotatably mounted in two laterally spaced narrow concave seats 28, which have a lower portion 38 ( Figure 2 ) to define the rotation axis of the actuating handle 3.

[0117] Projecting downwardly from the beam 109 is, for example, an oval shaped cam 112 which is drivably adjacent the head member 89 of the piercing pin, such as Fig.15 One or more stoppers 115, for example triangular in shape, protrude distally from the beam 109 to limit the pivotal movement of the actuating handle 3 by contacting an area of ​​the gas flow control assembly housing.

[0118] This configuration of the actuation handle 3 advantageously provides a mechanical advantage, i.e., the ratio of the longitudinal length L of the user operable surface 101 from a line 116 passing through its rotational axis coinciding with the beam 109 to the longitudinal length M of the cam 112 from the rotational axis is in the range of 16-22: 1, for example 20: 1. With this mechanical advantage, the force of average magnitude applied when raising the user operable surface 101 will output an amplified driving force of about 20 kg applied to the piercing pin, which is sufficient to pierce the metal cover 37 of the gas cartridge 21.

[0119] When the actuating handle 3 is Fig.14 and Fig.16 When the actuating handle 3 is pivoted about its rotational axis, the cam 112 attached thereto also pivots in a similar direction. In this pivoted position, the curved periphery of the cam 112 slidingly and drivingly contacts the head element 89 to an inwardly moved position so that the tip of the piercing pin pierces the metal cover. The curved groove 47 formed in the gas flow control assembly housing facilitates the pivotal movement of the arc-shaped extension 104 without interference. When the actuating handle 3 is pivoted in the opposite direction, the action is reversed.

[0120] Now refer to Figure 6 , Figure 7 , Fig.11 and Figure 17-Figure 20 The structure and operation of the pressure regulating unit 24 are described.

[0121] like Fig.17 As shown, the pressure regulating unit 24 has a housing 96 configured with an inner cavity, in which a piston 25 equipped with an O-ring 28 or any other suitable sealing element can be axially differentially moved to define a spring-based supply chamber 133 and a separate regulating chamber 134. The supply chamber 133 is supplied with atmospheric air through an opening 138 formed in the housing 96.

[0122] A thin hollow tube 26, connected to the piston 25, for example by an adhesive material 139 or alternatively by a fastener such as a threaded connection, passes through the entire thickness of the piston 25 and is in fluid communication with the regulating chamber 134. The tube 26 is adapted to receive pressurized gas discharged from the gas cartridge via the conduit 93 and pass the gas to the regulating chamber 134. A coil spring 129, which may be attached to the distal edge 137 of the supply chamber 133, surrounds the tube 26 and is used to control the pressure within the band.

[0123] The cap 30 may be metal and may be threadedly engaged with the housing 96 at the narrow end 98. The cap 30 is used to guide the pressurized gas to the tube 26. A flat sealing element 31, for example made of EPDM rubber, is attached to the proximal end of the cap 30 and is also attached to, for example, a flat annular flange element 32, which is configured to carry an elongated annular element 141, in which the tube 26 can be accommodated and axially displaceable. The annular element 141 has two openings 144 that may be diametrically opposite to each other. When the cap 30 is engaged to the housing 96 to the maximum extent, in combination with alignment means known to those skilled in the art, one of the openings 144 may be aligned with the conduit 93. Through various dedicated channels, such as channels of different diameters and directions, provided in the annular flange element 32 and the elongated element 141, the exhausted pressurized gas can flow from the conduit 93 to the aligned openings 144 without escape, and from the aligned openings to the distal end of the tube 26, i.e., near the cap 30. The proximal end of the elongate member 141 retains an O-ring 27, constituting an additional means for preventing the escape of pressurized gas.

[0124] Three secondary passages 152, 162 and 172 formed in the shell 29 connected to the housing 96 are in fluid communication with the regulating chamber 134. The first passage 152 is used to allow the pressurized gas to flow to the interior of the strap. The first passage 152 can be in communication with a threadably engageable seat 154, which is adapted to be engaged with the strap. Figure 7 and Fig.12 The exhaust conduit 114 is shown engaged, for example, detachably engaged. The manual pressure release actuator 4 is connected to the second passage 162. If the pressure of the pressurized gas rises close to a predetermined threshold, the pressurized gas can be released to the atmosphere through the third passage 172 via the safety valve 177, the structure of which is well known to those skilled in the art. Therefore, when a patient is treated in an emergency, sent to a hospital and treated in the hospital, the same pneumatic hemostat can be used to stop bleeding without worrying about excessive pressure of the gas.

[0125] When the compressed gas is initially discharged from the gas cartridge 21, since the atmospheric pressure in the supply chamber 133 is greater than or equal to the pressure in the regulating chamber 134 without compressed gas, there is an axial gap between the distal end of the tube 26 and the sealing element 31, and the spring 129 is biased to keep the piston at a predetermined interval from the distal edge 137 of the supply chamber 133. Therefore, the pressurized gas is introduced into the tube 26 and flows to the regulating chamber 134 via the first passage 152, thereby allowing the pressure in the inner part 53 of the band to increase. Finally, as the pressurized gas flows into the regulating chamber 134, the pressure in the regulating chamber 134 is greater than the pressure in the supply chamber 133 and greater than the biasing force of the spring 129, so that the piston 25 is forced to move distally. When the piston 25 moves sufficiently distally, the distal end of the tube 26 is blocked by the sealing element 31, preventing the pressurized gas from flowing in additionally. Therefore, the pressure in the inner part 53 of the band is maintained at a predetermined level, and sufficient pressurized gas is maintained in the gas cartridge 21 to achieve additional hemostatic operations and enable the pneumatic hemostat to be a multi-purpose hemostat.

[0126] Compared to prior art pressure regulators that rely on costly precision machining using a computer numerical control (CNC) lathe to achieve a reliable seal, the tube 26 may advantageously have an outer diameter 148 of less than 2.5 mm, provided that, for example, a tapered tube construction having a smooth finish and an outer diameter of at least 6 mm is formed integrally with the piston. At such a small size, Fig.18 The tube 26 shown can achieve a reliable seal by providing a tapered distal end 164 manufactured by low-cost cutting, without the need for a smooth finish, because the contact between the distal end and the sealing element, which only causes a slight depression of the sealing element, is sufficient to reliably block the tube 26. Other advantages of the small size tube include mechanical connection to the piston; reduced material removal time and cost because the tube is manufactured from a billet having a diameter substantially equal to the diameter of the tube, rather than the diameter of an integral larger size piston as previously practiced in the prior art; simple sealing; and reduced sealing force requirements due to the use of a small diameter tube.

[0127] Now refer to Figure 6 , Fig.12 , Fig.17 , Fig.19 and Fig. 20 The operation of the manual pressure release actuator 4 is described.

[0128] The manual pressure release actuator 4 includes a main rod 166 that can move axially in the second passage 162 of the housing 29 and cooperates with an O-ring 167 that is generally fitted in the second passage and has an outer diameter substantially equal to that of the second passage. A secondary rod 173 extends proximally from and below the proximal end of the main rod 166 and terminates in a protrusion 176 that can engage a finger. A stopper 178, such as an inclined stopper, extends proximally from the interface between the main rod 166 and the secondary rod 173 and is used to limit the proximal movement of the manual pressure release actuator 4 when contacting the housing element 33, such as Figure 7 shown.

[0129] Alternatively, the manual pressure release actuator may include a single rod extending distally from the protrusion 176 .

[0130] Fig.12 and Fig.19 The manual pressure release actuator 4 is shown when it is set to the retracted proximal position. In the retracted position, the main rod 166 is received in and engaged with the O-ring 167 that is sealingly engaged in the second passage 162, so that the second passage is blocked by the main rod 166 and the O-ring 167 to prevent the pressurized fluid received in the regulating chamber 134 from flowing out to the atmosphere.

[0131] If the medical staff wishes to reduce the internal pressure of the bandage to remove the hemostat from the patient or to prevent ischemia in the muscle tissue during prolonged use of the hemostat, the protrusion 176 can be pushed to move the main rod 166 and the O-ring 167 engaged therewith toward the distal end. Fig. 20 162, O-ring 167 moves outward from second passage 162 and enters regulating chamber 134, thereby generating a radial gap between main rod 166 and the wall of second passage 162. When main rod 166 is advanced to the maximum extent distally, it contacts piston 25 and causes the distal end of tube 26 to be blocked by sealing element 31. Since the distal end of tube 26 is blocked, pressurized gas is prevented from entering regulating chamber 134, and the fluid in regulating chamber 134 begins to be discharged to the atmosphere via the radial gap around main rod 166, so that the magnitude of the hemostatic force applied by the fluid pressure inside the bandage can be reduced. The magnitude of the hemostatic force can be reduced periodically at short time intervals, such as 10-15 minutes.

[0132] The degree of pressure reduction can be simply controlled by releasing the force applied to the protrusion 176. After the force applied to the protrusion 176 is released, the pressurized gas retained inside the band flows through the first channel 152 and keeps the piston 25 advanced distally. Finally, the main rod 166 separates from the piston 25 and then moves proximally in the second channel 162. The main rod 166 carries the O-ring 167 and allows the O-ring 167 to be accommodated again in the second channel 162 to block the radial gap.

[0133] If all of the pressurized gas is allowed to escape to the atmosphere, the supply chamber 133 and the regulating chamber 134 will reach an equilibrium state and the distal end of the tube 26 will no longer be blocked by the sealing element 141. Therefore, an additional amount of pressurized gas will be delivered to the regulating chamber 134.

[0134] The previously unknown ability to periodically deflate the cuff internally in the pre-hospital setting prevents ischemia, providing a significant clinical advantage despite the prolonged use of the pneumatic hemostat. Medical staff accompanying the patient to the hospital can monitor the patient's physiological status to avoid complications such as metabolic changes, reperfusion syndrome, and cardiac arrest.

[0135] In addition, when protrusion 176 is secured in the distal advanced position by a locking device movably connected to the gas flow control assembly housing, the distal end of tube 26 will remain blocked at all times, so that after the inflatable cuff is replaced, the pressurized gas remaining in the gas cartridge can be used to perform additional hemostatic procedures on other injured patients.

[0136] Fig.21 and Fig. 22 Another embodiment of a pneumatic hemostat 240 is shown which may be compactly stored by a plurality of spaced apart forks 276 extending laterally from a gas flow control assembly 243. The forks 276 are insertable and connectable to a slot 277 of a housing member 210 provided with a non-pivoting cinch 248. The slot 277 is sized to allow connection with the forks 276 and also to allow an inflatable strap to be fed thereunder along an engageable cinch surface of the rocker 211. The forks 276 are pressed together to release the gas flow control assembly 243 from the cinch 248. The operation of the gas flow control assembly 243 and the cinch 248 are respectively similar to Figure 1 The operation of the gas flow control assembly 43 and the tightening device 48 is the same.

[0137] Fig.23 Another embodiment of a pneumatic hemostat 340 is shown, which includes Fig. 22 The tightening device 248 described in the above and the gas flow control assembly 343 without the pressure regulating unit are combined to achieve a more compact structure. The gas flow control assembly 343 includes an actuating handle 3 of the same structure for starting the inflation of the strap 49; a piercing unit housing 18, in which the gas cartridge 21 is detachably connected; and a piercing pin 19 for piercing the metal cover that usually seals the gas cartridge, as described above with reference to Fig.11 and Fig.13 described. Figure 7 The connecting portion 46 shown can be used to attach the strap 49 to the gas flow control assembly housing. The pressurized gas flow discharged from the gas cartridge can be directed to the inflatable strap before flowing into the interior of the strap. Fig.17A relief valve 177 is shown in fluid communication with the internal chamber to prevent over-pressure.

[0138] A plurality of spaced apart fork members 276 ( Fig. 22 ) can be inserted into and connected to the slot 277 of the housing member 210 provided with the tightening device 248 for compact storage. The fork 276 is pressed together to release the gas flow control assembly 343 from the tightening device 248.

[0139] Figure 24-Figure 30 Another embodiment of a pneumatic hemostat 440 is shown.

[0140] like Fig.24 As shown, the pneumatic hemostat 440 includes a gas flow control assembly 443, which is provided with a user-friendly actuation handle 447; a non-pivoting restraint device 448, which can be connected to the gas flow control assembly 443, such as Fig.23 448, to provide a compact housing without a pressure regulator; and an inflatable strap 449 connected to the gas flow control assembly 443 and selectively clamped by the restraining device 448. In this embodiment, the inflatable strap 449 is constructed without an internal sealing layer; however, as will be described below, pressurized gas is prevented from reaching the free end of the strap from the clamping edge associated with the tightening device 448 by an external sealing element.

[0141] It should be understood that the inflatable band 449 may also be constructed with an internal sealing layer and the pneumatic hemostat 440 may be constructed with a pressure regulator.

[0142] Fig.25 Another embodiment of a gas flow control assembly is shown. When the actuation handle is removed, the gas flow control assembly 443 is shown positioned in abutment with the tightening device 448. A gas cartridge 461 equipped with a valve actuator to initiate the discharge of gas is shown as being removably coupled to a piston housing 468, such as by a threaded connection, and the piston housing 468 is composed of two differently sized portions 468a and 468b, for example. An elongated actuation piston 472 in a non-actuated position protrudes through an opening in the piston housing portion 468a so that its head 474 is aligned with a transversely extending shaft 476 ( Fig.29 ) spaced apart, i.e. relative to the longitudinal axis of the gas cartridge 461, the actuating handle is able to rotate around the longitudinal axis. After actuation, the actuating piston 472 is returned to the non-actuated position by the spring 471.

[0143] The gas flow control assembly 443 may also include a device for adjusting the gas pressure inside the band. A pressure release valve 477 for manually releasing the internal band pressure (e.g., slowly and controllably releasing the pressure before removing the hemostat from the subject) may be operably connected to the piston housing portion 468a. A pressure control mechanism 478 for automatically regulating the internal band pressure during deployment of the pneumatic hemostat may be operably connected to the piston housing portion 468a via a conduit. The pressure control mechanism 478 may have a selector 479 by which a user can select the pressure to be set.

[0144] like Fig.26 As shown, an inflatable bandage 449 having two different widths can be constructed with a plurality of sequentially interconnected cells, such as cells 456 to 458, which are adapted to help reduce the volume of the inflatable bandage interior, thereby reducing the volume of pressurized gas required to deliver sufficient hemostatic force to the injured limb relative to a pneumatic bandage lacking sequentially interconnected cells. Cells 456-458 are each attached to an outer longitudinally extending boundary layer 451 of bandage 449.

[0145] A plurality of identical and sequentially interconnected cells 458 may be provided at the narrower width portion 459. Cell 456 is provided at the wider width connecting portion 452, and a transition cell 457 of varying width is inserted between cell 456 and the cell 458 closest to cell 456. A short longitudinally extending neck 431 extends between two adjacent cells to facilitate the flow of pressurized gas from one cell to another. Two transverse protrusions 434a and 434b, for example, tooth-shaped, extend from opposite sides of the corresponding region of the boundary layer 451 to define the adjacent surface of the corresponding neck 431 and the adjacent cell, which is generally curved. An inlet 437 protrudes inwardly through the upper wall of the cell 456, through which the pressurized gas flows to the interior of the band, and a fastener 439 for connecting to the housing of the gas flow control assembly around the inlet 437 protrudes upward from the cell 456. Each fastener 439 may be a snap or other connector known to those skilled in the art, whether a removable device or a non-removable device, and may be spaced at different distances from the air inlet 437. Alternatively, all fasteners may be spaced equidistantly from the air inlet 437.

[0146] Fig.27A-B show a top view and a side view, respectively, of the strap 449 when inflated and not connected to the gas flow control assembly. In addition to the wider width cell 456 and the transition cell 457, the strap 449 is also constructed with a plurality of narrower width cells 458a-e, and pressurized gas can flow from the inlet 437 through the adjacent neck 431 of each cell to inflate the strap 449. The divider 467 adjacent to the cell 458e and the end cell 462 prevents pressurized gas from flowing to the end cell 462, ensuring that the uninflated end cell 462 has a minimum thickness so that the subject feels comfortable when the remaining portion of the strap 449 is wrapped around the subject's limb and inflated. Of course, when the clamping edge prevents pressurized gas from flowing to other portions of the inflatable strap 449 that protrude distally from the clamping edge of the tightening device and are adjacent to the end cell 462, the other portions may not be inflated.

[0147] Each unit is defined by an outer surface 453 and a limb-facing surface 454 of the strap 449 and transverse projections 434 respectively embedded in the outer surface 453 and the limb-facing surface 454. When the strap 449 is inflated, the transverse projections of the outer surface 453 separate from the corresponding transverse projections of the limb-facing surface 454 to form a pyramidal projection 434'. The apex of the pyramidal projection 434' protruding from the side of the outer surface 453 intersects the apex of the corresponding pyramidal projection 434' protruding from the side of the limb-facing surface 454 at a longitudinally extending weld line 481, which is the connecting interface between the outer surface 453 and the limb-facing surface 454.

[0148] Fig.27C The strap 449 is shown when the wider width unit 456 is connected to the gas flow control assembly 443 and the free end 462 of the strap is pre-fed into the tightening device 448. The attachment plate 506 ( Fig.33 ) and the screw 441 is connected to the corresponding fastener. The screw 441 can also pass through the hole 501 formed in the Figure 4 The holes on the bottom surface 41 of the embodiment of the present invention are provided to connect with corresponding fasteners. A plurality of narrower width units 458 extend circumferentially to the tightening device 448.

[0149] Fig.28AA cross-sectional view of the connecting portion 452 is shown. A flexible air inlet 437 protrudes through the outer layer 453 of the inflatable strap, and its central channel 438 is in fluid communication with the strap interior 465 located between the outer layer 453 of the inflatable strap and the limb-contactable layer 454. In order to reduce the stress concentration to which the connecting portion 452 is exposed, a semi-rigid sealing layer 424 formed with holes, such as made of polyurethane, thermoplastic polyurethane (TPU) or similar material, is attached to the air inlet 437 and the outer strap layer 453, such as by high-frequency brazing. The thickness of the semi-rigid sealing layer 424 can be in the range of 0.1-0.5 mm, such as 0.2 mm. Except for the hole configured to accommodate the air inlet, the semi-rigid sealing layer 424 has no small holes. The air inlet 437 also protrudes through a rigid plastic plate 427 which is also attached to the semi-rigid layer 424 and is made of, for example, high density polyethylene (HDPE) and polypropylene, from which a plurality of fasteners (eg, fasteners 439a - b ) protrude.

[0150] For example, Fig.28B -D, the air inlet 437 is configured with a mounting element 435 for attachment to the semi-rigid layer 424. The rigid plate 427 is configured with a hole 426 for accommodating the air inlet 437 and four bosses 428, each of which can be connected to a fastener (such as a screw) passing through a corresponding hole formed on the attachment plate of the gas flow control assembly housing. The outer strap layer 453 is further formed with four holes 463 to respectively accommodate the bosses 428, and is formed with a central hole 466 to accommodate the air inlet 437. After assembly, the connecting portion 452 is as shown in FIG. Fig.26 shown.

[0151] Prior art methods for connecting an inflatable band to a gas flow control assembly typically include a single threaded connection to a valve core. This single connection creates relatively high stress concentrations during deployment of the pneumatic hemostat, while the relatively high pressure inflatable band wrapped around the injured limb applies relatively high tension to the single threaded connection. Due to the high stress concentrations, small holes or perforations often form in the band, resulting in reduced internal band pressure and loss of pressurized gas. When the pneumatic hemostat is provided with additional features discovered in the present invention, such as a pivotable actuation handle, a tightening device, a safety release valve, and a self-adjusting pressure control mechanism, the additional features create vibration forces that increase stress concentrations when operated, thereby causing the high stress concentrations to be exacerbated at the connection of the inflatable band.

[0152] By using the connection portion 452, the inflatable strap is connected to the gas flow control assembly housing by multiple connections rather than a single connection, thereby advantageously significantly reducing the relatively high stress concentration. The inlet 437 is connected to the rigid attachment plate 506 ( Fig.33 ) protrudes and serves as a piston housing 468 ( Fig.27C) is connected, for example, removably connected, or otherwise accessible to an attachment plate, which is otherwise securely secured to the connecting portion 452 by a plurality of fasteners. When the strap is inflated, the air inlet 437 is pressed against the attachment plate 506, and additional pressurized gas can flow freely from the gas cartridge to the strap interior 465. The semi-rigid sealing layer 424 provides additional protection to prevent the pressurized gas from flowing out of the connecting portion 452.

[0153] Fig.29 The gas flow control assembly 443 is shown when the actuation handle 447 is set in a pivoted position. Two laterally spaced elongated mounting elements 482 are rotatably mounted on the shaft 476 to facilitate pivotal movement of the actuation handle 447, wherein the mounting elements 482 are substantially perpendicular to the generally flat user-operable surface 491. The end of one of the mounting elements 482 is shown in force-transmitting relationship with the actuation piston head 474.

[0154] Figure 30-Figure 31 The operation of an actuating piston 472, which acts as a force transmitting element when cooperating with the actuating handle 447, is shown. The actuating piston 472 is longitudinally guided in a longitudinal slot formed in the piston housing 468 (not shown). The actuating piston 472 carries an angled guide tube 494.

[0155] exist Fig.30 4, the actuating handle 447 is in a non-pivoted position, the actuating piston 472 is arranged in a non-actuated position, and the side edge of the mounting element 482 is in abutting relationship with the actuating piston head 474. The distal end of the actuating piston 472 is slightly spaced apart from the valve stem 464 of the gas cartridge 461, which is shown in a protruding position. In the non-actuated position of the actuating piston 472, the short flat extension of the conduit 494 is not aligned with the conduit 497 (only a portion is shown) fixed to the exhaust port 469 of the piston housing 468 and extending through the inlet port of the inflatable strap 449 to prevent the strap from being inflated due to leakage of pressurized gas. During non-use, leakage of pressurized gas from the gas cartridge 461 is also prevented by an annular seal 496 fixed to the base of the valve stem 464. The conduit 497 is spaced apart from the actuating piston 472 by a small gap.

[0156] exist Fig.31In the embodiment, the actuating handle 447 pivots and transmits the actuating force to the actuating piston 472 through the head 474, while the spring 471 fixed to the recessed portion of the piston housing is compressed. The actuating piston 472 is thereby moved longitudinally until the short flat extension of the conduit 494 is aligned with the conduit 497. The actuating piston 472 thus contacts the valve stem 464 and retracts it, thereby opening the valve seat and allowing pressurized gas to flow from the interior of the gas cartridge 461 to the conduit 494 via the valve seat. Since the conduit 494 is aligned with the conduit 497, the pressurized gas will also flow to the interior of the band via the air inlet. A plurality of annular seals 483 surrounding the conduit 494 prevent gas from leaking from the adjacent area between the conduit 494 and the conduit 497. In one embodiment, a pressure gauge 513 that is intuitively apparent and schematically shown and is connected to the fluid inside the band indicates when the interior of the band is inflated. In another embodiment, when gas is discharged from the pressure control mechanism 478 ( Fig.27C ) is released, in response to the audible reaction produced by the pressure control mechanism 478, the user stops inflating the interior of the strap with pressurized gas.

[0157] When the actuation force is released, the spring force of the spring 471 surrounding the actuation piston 472 is released, thereby pushing the actuation handle 447 to the non-pivoted position, and the conduit 494 becomes misaligned with the conduit 497, as shown in FIG. Fig.30 In addition, the spring around the valve stem 464 stops being compressed and the valve stem returns to the protruding position.

[0158] Alternatively, the actuating piston 472 may be longitudinally driven by a button 541 protruding from the lower housing 538 of the gas flow control assembly 443 or any other actuator, such as Fig.27C As shown in . When the actuation force is transmitted, the movable rod 543 connected to the button 541 or in a force transmitting relationship therewith is driven longitudinally to move the actuation piston head 474 toward the proximal end. The operation of the actuation piston is as described above.

[0159] It will be appreciated that the actuating piston 472 may be used to drive Fig.11 The piercing pin 19 is shown.

[0160] The pressurized gas exhausted from the gas cartridge 461 after the actuation force is transmitted can be in fluid communication with the pressure relief valve 477 and the pressure control mechanism 478 through corresponding conduits also fixed to the piston housing 468. The conduit 494 carried by the actuation piston 472 can be configured with additional angled sections, each of which can be similar to Fig.31 In order to provide the desired pressure control function, each corresponding conduit can be equipped with a valve or other pressure biasing mechanism, and optionally with a sealing element.

[0161] Now refer to Fig.32A, showing a cross-sectional view of a portion of the tightening device 448A. In addition to the addition of the sealing element 533, the housing member 510 and the rocker 521 are configured to Fig. 9 534 is substantially shorter than the distance to the distal leg 536. The distal leg 536 may be substantially longer than the proximal leg 534. In addition, the side wall 514 of the housing member 510 is formed with a narrow gap in which the longitudinally extending outer sealing element 533 is fixed. The outer sealing element 533 is also formed in the side wall 514 of the housing member 510. Fig.32B and Fig.33 As shown in Fig.32B As shown, when the rocker 521 rotates in response to contact with the injured limb and a tensile force is applied to the inflatable strap 449, a clamping force is exerted on the strap. An external sealing element 533, preferably semi-rigid (e.g., 70 Shore A hardness), located at the clamping edge supplements the clamping force to prevent pressurized gas from flowing to the free end of the strap 449. Thus, the free end of the strap is not inflated, making it more comfortable for the subject and less susceptible to puncture.

[0162] Fig.34 A tightening device 448B is shown configured with an external sealing element 537 attached to the proximal leg 534 of the rocker.

[0163] Fig.35 A tightening device 448C configured with an outer sealing element 533 and an outer sealing element 537 is shown.

[0164] For example, Fig.32B The hemostat is well suited for use in warfare as a small hemostat that can be compactly stored in a soldier's backpack or other storage equipment.

[0165] Here are some of the beneficial features of this small hemostat:

[0166] i. Small gas cartridges - The gas cartridge has a volume in the range of 3-7 ml, which is smaller than the standard volume of 7 ml. The relatively small size of the gas cartridge can be fully inserted into the gas flow control assembly without protruding outward therefrom, which can prevent the gas cartridge from being accidentally separated from the gas flow control assembly and damaged, which is a significant advantage in terms of reliability and safety.

[0167] ii. Environmental adaptability - The use of inert gases, such as nitrogen or argon, or refrigerant gases, which are stored in gaseous form in gas cartridges without the risk of freezing, enables the pneumatic hemostat to operate in a wide temperature range of -40°C to +70°C. Since it is not affected by atmospheric pressure, the hemostat can also operate in different environments, such as on land, in the air or underwater.

[0168] iii. Actuation - The actuator, whether an actuation handle or a button, has sufficient structural strength to transmit the high magnitude of actuation force that causes the pressurized gas to be discharged from the gas cartridge. The structure of the actuation handle facilitates simple and intuitive operation, thereby achieving hemostasis in only a few seconds.

[0169] iv. Inflatable bandage with two widths and interconnected cells - The unique bandage structure has a narrower width and smaller internal volume than inflatable bandages in the prior art. The wider width portion enables the force required to achieve hemostasis to be reduced, and the narrower width portion constructed with interconnected cells allows the use of a smaller volume of pressurized gas relative to an inflatable bandage without interconnected cells. The wider width portion (which compresses the limb when inflated) allows the bandage to be applied to small limbs without causing injury, while the long and narrow width portion allows the bandage to be applied to large limbs, such as 85 cm in circumference.

[0170] v. Automatic Pressure Release Valve - When the band is inflated to a constant preset pressure, it is not necessary to utilize the entire volume of pressurized gas retained in the gas cartridge. When the interior of the band reaches a predetermined high pressure, the pressure release valve will allow some of the gas from the interior of the band to vent to the atmosphere to ensure that the pressure inside the band will drop to the preset pressure. In some embodiments, the pressure release valve emits an audible response, such as a hissing sound, to indicate to the user when to terminate the band inflation.

[0171] vi. Snap-on connection between gas flow control assembly and tightening device - a fork-shaped piece extending laterally from the gas flow control assembly and insertable into a slot in a non-pivoting tightening device facilitates a simple and intuitive connection that withstands high pressure and prevents accidental separation.

[0172] vii. Tightening Device - The tightening device enables smooth movement of the strap and also enables one-handed operation of the strap to facilitate self-deployment of the strap.

[0173] Although some embodiments of the present invention have been described by way of illustration, it is apparent that the present invention may be implemented through numerous variations, changes and modifications, and by utilizing numerous equivalents or alternatives within the purview of those skilled in the art, without departing from the scope of the claims.

Claims

1. An inflatable hemostat, comprising: an assembly having a flexible discharge port, at least one conduit for delivering gas from a gas cartridge, and a rigid plate; a strap having an outer layer and an inner layer sealed to each other to form an interior, a flexible air inlet disposed between the outer layer and the inner layer, and a panel engaged with the flexible air inlet; and The strap is attached to the assembly via a plurality of fasteners on a panel of the strap such that the flexible exhaust port is releasably engaged with the flexible inlet port.

2. The inflatable hemostat of claim 1, further comprising a sealing layer disposed between the outer layer and the inner layer.

3. The inflatable hemostat of claim 2, wherein: The sealing layer is disposed on a first side of the flexible air inlet, and the panel of the strap is disposed on a second side of the flexible air inlet.

4. The inflatable hemostat of claim 1, wherein: The binding tape has a third sealing layer.

5. The inflatable hemostat of claim 1, wherein: The flexible drain port protrudes from the rigid plate of the assembly.

6. The inflatable hemostat of claim 1, wherein: The plurality of fasteners are integrally formed on the panels of the strap.

7. The inflatable hemostat of claim 6, wherein: The panels of the strap are attached to the outer layer.

8. The inflatable hemostat of claim 1, wherein: The plate of the strap has an aperture through which the flexible air inlet protrudes.

9. The inflatable hemostat of claim 1, wherein: The flexible discharge port includes a tapered fitting.

10. The inflatable hemostat of claim 1, wherein: The flexible air inlet has an abutment connected to a panel of the strap.

11. The inflatable hemostat of claim 1 further comprising a pivotable tightening device engaged with the strap.

12. The inflatable hemostat of claim 11, wherein: The pivotable tightening device, assembly and strap are assembled together.

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