80 results about "Blood outflow" patented technology

A blood pump-oxygenator system (250A, 250B, 250C) for increasing perfusion and oxygen levels in the body of a patient (P), comprising: a blood inlet (80) and a blood outlet (90) connected to form a circuit operable as a cardiopulmonary bypass system suitable for extracorporeal treatment of the blood of the patient; a first blood pump (11) and a first oxygenator (20), wherein the first blood pump (11) is configured to deliver blood from the patient (P) through the circuit to the blood inflow port (80), through the first oxygenator (20), out of the blood outflow port (90) and back to the patient (P). The system further comprises a second blood pump (13) and a second oxygenator (21), wherein the second blood pump (13) is configured to deliver blood from the patient (P) through the circuit to the blood inflow port (80), through the second oxygenator (20), out of the blood outflow port (90) and back to the patient (P). The circuit comprises a first branch (101) and a second branch (102) arranged in parallel with each other, the first branch (101) accommodating the first blood pump (11) and the first oxygenator (20), and the second branch (102) accommodating the second blood pump (13) and the second oxygenator (21). The system further comprises a pump control unit (290) wherein the first and second blood pumps (11, 13) are configured to be controlled by the pump control unit (290) to increase or decrease the blood flow through the corresponding oxygenator (20, 21) by changing the proportion of the blood flow through the first and second oxygenator (20, 21).

The utility model relates to a catheter type ventricular assist system which can provide different flows and is small in trauma, and comprises a single-channel double-cavity cannula and a single-channel single-cavity cannula, the single-channel double-cavity cannula comprises an inner tube and an outer tube, the near end of the inner tube is communicated with an inlet tube of a blood pump, and an outlet tube of the blood pump is communicated with the near end of the outer tube or the near end of the single-channel single-cavity cannula. Blood is sucked in from the blood inflow port at the far end of the inner tube and flows out from the blood outflow port at the far end of the outer tube to form a small-flow circulation auxiliary system, and blood is sucked in from the blood inflow port at the far end of the inner tube and flows out from the opening at the far end of the single-channel single-cavity cannula to form a large-flow circulation auxiliary system. By means of the mode that the outer tube and the single-channel single-cavity cannula are switched, one set of ventricle auxiliary device can meet small-flow circulation assistance and large-flow circulation assistance, and the ventricle auxiliary device is suitable for different scenes. In small-flow circulation assistance, the outer tube and the inner tube are single-channel double-cavity intubation tubes, the single-channel double-cavity intubation tubes can be intervened to the designated position only through one incision, trauma is small, and postoperative recovery is fast.

An example aneurysm implant can include a tubular braid that can have an open end, a pinched end, and a predetermined shape. In the predetermined shape, the tubular braid can have three segments and two inversions, one of the three segments extending between the two inversions and forming a sack. Two of the segments can form a substantially semispherical shape. The tubular braid can be implanted in an implanted shape based on the predetermined shape. The substantially semispherical shape of the tubular braid can aid in decreasing a pulsatile blood inflow rate and a pulsatile blood outflow rate for a substantially spherical aneurysm cavity.

A blood pump comprises a pump casing having a blood flow inlet and a blood flow outlet, and an impeller arranged in said pump casing so as to be rotatable about an axis of rotation. The impeller has blades sized and shaped for conveying blood from the blood flow inlet to the blood flow outlet. The blood pump also has an outflow cannula having an upstream end portion, a downstream end portion and an intermediate portion extending between the upstream end portion and the downstream end portion. The upstream end portion of the outflow cannula is connected to the pump casing such that blood is conveyed from the blood flow outlet of the pump casing into and through the intermediate portion of the outflow cannula towards the downstream end portion of the outflow cannula, wherein the downstream end portion has a blood flow outlet through which blood can exit the outflow cannula. At least a portion of the intermediate portion of the outflow cannula has an outer diameter that is larger than an outer diameter of the pump casing.

An intravascular blood pump (1) comprises a pump housing (2) having a blood inflow (21) and a blood outflow (22), and an impeller (3) arranged in the pump housing (2) to be rotatable about an axis of rotation, wherein the impeller (3) has blades (31) which are dimensioned and shaped for conveying blood from the blood inflow (21) to the blood outflow (22). The blood pump (1) further comprises a drive unit (4) for rotating the impeller (3), the drive unit (4) comprising a plurality of posts (40) arranged about the axis of rotation (10), wherein each of the posts (40) comprises a stem portion (41) and a head portion (42). Coil windings (470) around the posts are controllable in sequence to generate a rotating magnetic field. The drive unit (4) further comprises a back plate (50) which engages with the end (44) of the stem portion (41) of the posts (40) opposite the head portion (42).

The invention relates to the technical field of medical instruments, and discloses a two-way valve and a ventricle assisting device. The two-way valve comprises a valve body, the valve body is of a tubular structure with a proximal end and a telecentric end, a window is formed in the side wall of one side of the valve body, and a first contact area is arranged on the edge of the end, close to the telecentric end, of the window on the inner side wall of the valve body; the valve clack is rotatably arranged in the valve body, a concave part is arranged on the side, facing the window, of a telecentric arc section of the valve clack, a valve clack contact area is arranged at the position, opposite to the first contact area, of the valve clack, and the valve clack can rotate between a first state position and a second state position relative to the valve body. The opening window is opened or closed. According to the technical scheme, when the valve clack rotates to the first state position, the blood outflow path is increased due to the concave part of the telecentric arc section of the valve clack, so that the blood outflow amount is further increased, and the effect of assisting in pumping out blood is improved.

The device comprises a base, a controller is arranged on the outer side of the base, a cleaning mechanism is arranged at the top of the base, a clamping and pressurizing mechanism is installed at the top of the base, the cleaning mechanism comprises a cleaning box, an extraction pump is fixedly connected to the outer side of the cleaning box, and the extraction pump is fixedly connected to the outer side of the cleaning box. According to the pressurized cleaning device for the wounds after the acupuncture injury, a screw rod moves to drive an extrusion rod to move, so that the extrusion rod pushes a clamping plate on the outer side of a moving rod, and when the clamping plate moves to the outer sides of the arms and the two hands, the arms and the two hands can be kept stable at the top of the base; according to the device, the effect of clamping the arm is achieved, at the moment, a first electric telescopic rod is started through a controller, so that the first electric telescopic rod drives a pressurizing cover to move downwards, then the pressurizing cover extrudes the puncture position of the arm, blood flows out, and follow-up cleaning is facilitated.

The invention discloses a platelet aggregation function detection kit. Comprising a sample pool and a biochemical active membrane integrated part, the sample pool is a cavity capable of accommodating citrate anticoagulant whole blood; a sample adding opening is formed in the top of the sample pool; the sample adding opening and the biochemical active membrane integrated part are separated at the top; a biochemical active membrane is flatly spread in the center of the biochemical active membrane integrated part; a membrane pore is formed in the center of the biochemical active membrane; the biochemical active membrane comprises a membrane surface coating; the membrane surface coating is formed by combining collagen and ristomycin; the platelet aggregation state can be more accurately judged according to a biochemical active membrane formed by two platelet inducers, namely collagen and ristomycin; a special structure formed by the capillary tube, the biochemical active membrane integrated piece, the sample pool and the biochemical active membrane can simulate the process from blood flowing out of a blood vessel to coagulation in vitro.

The foldable blood pump for right heart assistance is small in intervention size, large in flow and small in blood damage and comprises an expandable and contractible pumping assembly, the near end of the pumping assembly is connected with an in-vitro driving unit through a flexible transmission unit, the pumping assembly comprises a foldable impeller and an expandable shell arranged on the periphery of the foldable impeller in a covering mode, and the expandable shell is connected with the foldable impeller. The thin film extends from the middle section of the expandable shell to the far side and extends to the catheter outside the expandable shell, the near section of the expandable shell forms a blood inflow port, and a blood outflow port is formed in the far end of the thin film. The impeller is of a foldable structure, large flow can be obtained at a low rotating speed, damage to cells in blood caused by too large rotating speed is reduced, the motor is externally arranged, and the temperature rise and fault risks of motor operation are effectively avoided. Meanwhile, an interventional artery passage is straight and short, abrasion and vibration of the shaft sleeve caused by bending of the flexible shaft are greatly reduced, power loss is reduced, power transmission efficiency is greatly improved, and controllability of the motor to the impeller and stability of power transmission are also improved.

The present invention discloses a guide device for inserting a guidewire for cardiovascular interventional surgery, belonging to the technical field of guidewire guidance. The device comprises a guide seat, a guidewire guiding and twisting assembly comprising a slider, a positioning pin elastically and slidably inserted on the slider, a second dial rotatably connected to the slider, and the second dial elastically connected to the first dial; the guidewire is clamped by the first dial and the second dial, both of which are fan-shaped structures and form a circular wheel, and the guidewire is inserted into a catheter sheath along the guide seat through the reciprocating circular wheel; the first dial and the second dial are toggled and placed on the slider, and the circular wheel clamps the guidewire; the positioning pin is squeezed and inserted into the guide seat by the second dial, thereby preventing blood from flowing out of the catheter sheath and contaminating the doctor's hands, the guidewire, and the catheter sheath. The guidewire is inserted into the catheter sheath by the guidewire guiding and twisting assembly through the reciprocating movement of the guidewire stored in the guidewire storage tube, thereby preventing the guidewire from accidentally being pulled out of the catheter sheath and causing blood vessels to be scratched.

A vascular implant is provided for increasing the efficiency of blood flow through an aorta. The vascular implant includes a tubular shunt having a lumen for allowing blood to pass between an aorta and an inferior vena cava. An expandable reservoir is sized for placement in the inferior vena cava. The reservoir has a first region coupled to the tubular shunt and may include a second region formed with an exit port for allowing some blood to escape the reservoir into the inferior vena cava. The exit port reduces the possibility of stagnation in the reservoir. High pressure blood from the aorta temporarily passes through the tubular shunt and into the reservoir, such as during systole. When blood pressure reduces in the aorta, blood from the reservoir passes from the reservoir and through the shunt where it reenters the aorta, such as during diastole.

The utility model discloses a blood collecting and separating device which comprises a separating cup, the separating cup comprises a cup body, a cup cover, a static head, an upper cover and a lower cover, a blood inlet and a blood outlet in the top of the static head are both vertically arranged, and the upper cover and the lower cover are connected with the bottom of the static head; the upper end of the lower cover is communicated with the blood inlet to form a blood inflow channel, and a space between the inner walls of the upper cover and the lower cover is communicated with the blood outlet to form a blood outflow channel; the liquid inlet end of the blood inflow channel penetrates through the cup cover along the interior of the lower cover and extends into the bottom of the cup body; the liquid outlet end of the blood outflow channel penetrates through the cup cover to be located at the cup opening along the top of the cup body and enters the gap between the upper cover and the lower cover. By improving the structure of the static head, automatic assembly of the separation cup and a consumable pipeline during use can be facilitated, meanwhile, automatic assembly in the production process of the separation cup can be facilitated by improving the connecting structure between the static head and the upper cover and the connecting structure between the static head and the lower cover, and production efficiency is improved.

The application relates to the technical field of medical devices, in particular to a catheter pump assembly and a processing method thereof. The catheter pump assembly comprises a blood flow channel, a blood inflow cage and a blood outflow cage. The blood flow channel comprises a spring body support which is coiled by a shape memory alloy wire. The inner side of the spring body support is covered with an inner layer film, and the outer side is covered with an outer layer film. The two ends of the inner layer film and the outer layer film respectively extend to the two ends close to the spring body support, so that at least part of the spring body support is located at the connecting part of the blood flow channel, the blood inflow cage and the blood outflow cage. According to the technical scheme provided by the application, the connecting part of at least part of the blood flow channel, the blood inflow cage and the blood outflow cage is supported by the spring body support, thereby improving the bending resistance of the connecting part of the blood inflow cage, the blood outflow cage and the blood flow channel, overcoming the risk of breakage or falling of the connecting part, and ensuring the reliability of the catheter pump in use.

The present invention provides a vascular occlusion device, which includes a handle, a sheath, a puncture guide wire, a positioning guide wire and a push rod. The positioning guide wire and the push rod are arranged side by side and inserted into the inner cavity of the sheath. A plug corresponding to the push rod is provided at the distal end of the sheath. The occluder can be used without an arterial sheath (long sheath). The puncture guide wire is conveyed into the blood return port at the distal end of the sheath and led out through the guide wire exchange port. The normal use of the puncture guide wire is realized by adding an independent puncture guide wire channel. After the puncture guide wire is withdrawn, it is judged whether the blood return port at the distal end is inserted into the blood vessel according to the blood outflow condition of the guide wire exchange port. During the use process, there is no need to replace the long sheath and the short sheath, which improves the treatment efficiency and reduces the physical injury of the patient.

The invention relates to an interventional catheter pump, and belongs to the technical field of medical instruments. The catheter pump comprises a driving assembly and an intervention assembly, and the intervention assembly at least comprises a catheter and a pump head. During use, the driving assembly is located outside the human body, the pump head is located in the heart, and the driving assembly transmits power to the pump head through the power transmission assembly in the catheter. The pump head at least comprises a support and a covering film, the near end of the covering film is fixedly connected to the catheter and provided with at least one outlet for blood to flow out, and the far end of the covering film is matched with the support to synchronously change along with folding and unfolding of the support. When the stent is in a natural unfolding state, the covering film is in a folded state, and at least two folds are distributed from the near end to the far end. In a working state, folds of the covering film are basically flattened, the outer diameter of the covering film is in a decreasing trend from the near end to the far end, and the covering film and the heart valve are basically kept in circumferential fit in the valve closing period.

An arterial cannula for ECMO includes a main arterial cannula with an inner wall and having a first end with a blood outflow port. The first end is intended to be introduced into an artery so as to inject the blood retrogradely into the artery. A retro-perfusion cannula is configured to be translatably movable between a retracted position in the first end of the main arterial cannula and a deployed position at least partly outside the main arterial cannula and opposite the blood outflow port of the main arterial cannula.

This invention relates to an intravascular blood pump, comprising a pumping device with a pump section and a drive section, wherein the pump section comprises a pump casing having a primary blood flow inlet and a primary blood flow outlet hydraulically connected by a primary passage and the drive section comprises a stator and a rotor rotatable about an axis of rotation and configured to rotate a primary impeller, the primary impeller being configured to convey a primary blood flow from the primary blood flow inlet to the primary blood flow outlet along the primary passage, the drive section further comprises an ancillary blood flow inlet and an ancillary blood flow outlet hydraulically connected by an ancillary passage extending through an axial gap between the rotor and the stator and an ancillary impeller arranged at a drive section end (DSE) of the rotor and rotatable about the axis of rotation along with the rotor, the ancillary impeller comprising one or more ancillary impeller vanes configured to convey an ancillary blood flow (ABF) from the ancillary blood flow inlet to the ancillary blood flow outlet along the ancillary passage in a direction toward a pump section end (PSE) of the pumping device, and the rotor is mounted in a blood-purged radial sliding rotor bearing with an inner rotor bearing surface and an outer rotor bearing surface, and the ancillary impeller forms the inner rotor bearing surface of the radial sliding rotor bearing.

The invention discloses a spherical drill with stabs, and relates to the field of medical instruments, the spherical drill with stabs comprises a spherical working end and a connecting handle, the spherical outer surface of the spherical working end is provided with a plurality of miniature conical protrusions which are orderly distributed in space, and the miniature conical protrusions are used for cutting or disturbing a target bone surface in a rotating state; the diameter of the protruding part is 0.4-0.6 mm, the height of the protruding part is 0.6-0.8 mm, the whole protruding part is distributed in an axial symmetry mode and can be arranged in a plurality of longitude and latitude directions, the arrangement modes are diversified, the total length of the drill body is 30-45 mm, the drill body is suitable for low-speed power equipment, the structure can be integrally formed or assembled in a high-precision mode, and the drill body is made of materials with good biocompatibility. According to the invention, an operation area can be slightly cut while the integrity of a bone bed is kept, so that the hard tooth extraction fossa inner wall, the periodontal bone wall and the hole wall of the bionic implant fossa become soft, the outflow of blood is promoted, the secretion of growth factors and the climbing of osteoblasts are stimulated, and the healing of the operation area is promoted.

The invention discloses a catheter implantation system of a percutaneous intervention type axial flow blood pump. The catheter implantation system comprises the axial flow blood pump and a conveying device matched with the axial flow blood pump. The axial flow blood pump comprises an impeller assembly, a flexible shaft transmission assembly and a handle assembly, the impeller assembly and the handle assembly are connected through the flexible shaft transmission assembly, and the impeller assembly comprises an elastic support, a covering film, a blood pump body, an impeller rotor, an impeller shaft, a far-end supporting bearing, a cage frame and a flow guide tail cone; the elastic support structure is made into a petal shape, and the covering film wraps and fixes the root of the elastic support to the cylindrical surface of the blood pump body. The cage frame and the blood pump body are integrally machined and manufactured, the cage frame and the flow guide tail cone are welded, the two far-end supporting bearings are installed at the two ends of an inner hole cavity of the flow guide tail cone, the impeller shaft penetrates through the far-end supporting bearings, the far end of the impeller shaft is fixedly connected with the impeller rotor, and the impeller rotor is located in the blood pump body. A blood outflow hole is formed between every two adjacent cage frames.

A blood pump-oxygenator system for increasing perfusion and oxygen level in a patient comprises a blood flow inlet and outlet forming a circuit operable as a cardiopulmonary bypass system for extracorporeal processing of blood, a first blood pump and first oxygenator. The first blood pump conveys blood through the circuit from the patient into the blood flow inlet, through the first oxygenator and out of the blood flow outlet back into the patient. The system further comprises a second blood pump and second oxygenator. The second blood pump conveys blood through the circuit from the patient into the inlet, through the second oxygenator and out of the outlet back into the patient. A pump control unit controls the first and second pumps to increase or decrease blood flow rate through the respective oxygenator to vary a ratio of flow rates of blood through the first and second oxygenators.

An oxygenator system includes: a canister; a membrane in the canister to provide a gas transfer with blood; a blood inflow tube to deliver blood to the canister; and a blood outflow tube to deliver blood from the canister, wherein one or more of the blood inflow tube or the blood outflow tube includes a curved portion.

The invention discloses a filling type catheter and a ventricular auxiliary device, and belongs to the technical field of medical instruments. The catheter in the aorta comprises a multi-cavity catheter body, a first cavity and a second cavity which are isolated from each other are arranged in the catheter body, a blood inlet is formed in the proximal end of the first cavity and communicated with blood in the aorta, and medium fluid flows in the second cavity and is not communicated with the blood. A bleeding part is arranged on the multi-cavity tube body and comprises a bleeding hole formed in the tube wall and a balloon which can be filled and is located on the side, close to the heart end, of the bleeding hole. The fillable balloon is communicated with the second cavity through an extension pipeline with supporting performance, when the fillable balloon is in the first state, the filling medium is bulged and blocks the sealed bleeding hole, and when the fillable balloon is in the second state, the non-filling medium is away from the bleeding hole and opens the bleeding hole to enable blood to flow out. The ventricular auxiliary device further comprises a diaphragm pump and a control host, and the control host drives the diaphragm pump to suck or pump blood and controls the full balloon to expand or contract. Accurate control of blood flow is achieved through the controllable balloon, and effective auxiliary circulation support is provided for patients with heart diseases.

Various aspects of this disclosure are directed toward a percutaneous circulatory support device for use with a guidewire, the device comprising a housing having an interior lumen, an exterior surface, a blood inlet, and a blood outlet that includes at least one blood outflow window. An impeller is disposed within the interior lumen, with the impeller configured to rotate relative to the housing to cause blood flow into the blood inlet, through the interior lumen of the housing, and out of the blood outlet. A motor is operatively coupled to the impeller, the motor configured to rotatably drive the impeller, wherein the exterior surface of the housing adjacent the at least one blood outflow window comprises a marking.

The present invention relates to the technical field of medical devices, and discloses an artificial valve device. The artificial valve device includes a stent, and the stent includes a first mesh structure layer, a second mesh structure layer, and a third mesh structure layer. The first mesh structure layer, the second mesh structure layer, and the third mesh structure layer are distributed in sequence along the direction from the blood outflow end to the blood flow inflow end. The length of the support rod portion of the first mesh structure layer, the length of the support rod portion of the second mesh structure layer, and the length of the support rod portion of the third mesh structure layer decrease in sequence. The artificial valve device also includes a valve, and the valve is connected to the stent. In the above manner, the present invention can improve the axial positioning performance of the artificial valve device and is conducive to preventing paravalvular leakage.

To provide an intravascular blood pump for assisting a left ventricle of a heart of a patient.SOLUTION: An intravascular blood pump for percutaneous insertion to a blood vascular system of a patient includes a pump device 30 and a supply catheter 36. The pump device includes a pump part including a blood inflow port, a blood outflow port, and an impeller for transporting blood from the inflow port to the outflow port. The pump device further includes a drive part connected to the pump part and adapted to drive the impeller. A supply line supplies electric energy for driving the impeller to the drive part. The supply catheter 36 supplies electric energy for driving the impeller. The pump part 32 is arranged between the drive part 31 and the supply line 36 in an axial direction. The pump part includes a cannula 35 flexibly bendable. A power transmission line 44 is arranged across the cannula 35 so as to prevent burst in a phenomenon in which the cannula 35 bends.SELECTED DRAWING: Figure 11

The utility model relates to the technical field of centrifugal machines, and discloses a centrifugal machine facilitating uncapping of blood collection tubes, which comprises a centrifugal machine body, a mounting shaft is rotatably arranged in the centrifugal machine body, a detachable rotating frame is mounted on the mounting shaft, a plurality of mounting grooves distributed annularly are formed in the detachable rotating frame, and hanging baskets are mounted in the mounting grooves. A plurality of test tube insertion holes which are distributed at intervals are formed in the hanging basket and are used for placing blood collection tubes; when the blood collection device is used, the blood collection tube is placed in the test tube insertion hole of the hanging basket, and the cover plate assembly is matched with the elastic supporting assembly to extrude the test tube cap at the top of the blood collection tube, so that the phenomenon that blood in the blood collection tube flows out due to the fact that the test tube cap falls off in the centrifugal process is avoided; in addition, the blood collection tubes with different diameters placed in the test tube insertion holes can be clamped and fixed through the arranged clamping assembly, and damage and leakage caused by collision of the blood collection tubes and the inner walls of the test tube insertion holes in the centrifugal process are avoided.

An intravascular blood pump for percutaneous insertion into a patient's vasculature comprises a pumping device (30) and a supply catheter. The pumping device comprises a pump section with a blood flow inlet, blood flow outlet, and impeller for conveying blood from the inlet to the outlet and further comprises a drive section connected to the pump section and adapted to drive the impeller. The supply line supplies the drive section with electric energy for driving the impeller. An anchoring structure (25A) is provided at a distal end region of the intravascular blood pump. A connecting catheter (25) may be attached to the anchoring structure from distally in order to guide the intravascular blood pump through the patient's vasculature in a distal direction.

The application aims to provide a series blood pump with large flow and small hemolysis, comprising a blood flow channel and a pumping unit, one end of the blood flow channel is provided with a blood inflow port, the other end is provided with a blood outflow port, the pumping unit comprises an impeller and a motor set for driving the impeller to rotate, the blood pump is used in the process of interventional heart through blood vessels, the plurality of motors are separated from each other, the length of the continuous rigid section is reduced, and therefore the over-bending requirement of the blood vessel can be met; after reaching the designated position in the heart, the connecting mechanism drives the adjacent motors to be connected into a whole, that is, the torques of the plurality of motors are superposed, and therefore a larger load-impeller can be driven to rotate, so that the pumping flow of the blood pump is increased. Under the premise that the flow meets the human body demand, the rotating speed of the series blood pump can be greatly reduced compared with the common blood pump, and therefore the hemolysis can be further reduced.

The invention discloses an anti-displacement artificial heart valve stent, and relates to the technical field of valve stents.The anti-displacement artificial heart valve stent comprises a stent body which is of a net-tube-shaped structure and comprises an inflow section, a transition section and an outflow section which are sequentially arranged in the axial direction, and a valve blade is arranged in the transition section; the end, away from the transition section, of the inflow section is an inflow end for blood inflow, and the end, away from the transition section, of the outflow section is an outflow end for blood outflow. In a natural state, the inflow end and the outflow end are gradually expanded outwards in the direction away from the transition section; the auxetic section is arranged between the transition section and the outflow section in the axis direction of the stent body; the auxetic section is of a geometrical structure with the negative Poisson's ratio characteristic, and when the auxetic section is subjected to axial impact force of blood, the auxetic section deforms to convert axial stretching displacement into radial expansion displacement. According to the present invention, the anti-displacement performance is excellent, the blood vessel is not damaged, and the long-term stability and reliability are provided.

The present disclosure provides methods and devices for removing particles from fluids. A method for removing red blood cells includes obtaining a device having a microstructured substrate including microstructures extending across a first surface, where at least a portion of an exterior surface of the microstructures are configured to allow capillary action. The device also includes a cover disposed a selected distance apart from a top of the first surface of the microstructured substrate and at least one sidewall that attaches the cover to the first surface of the microstructured substrate along a perimeter of the first surface of the microstructured substrate. The method further includes filling the device with a volume of blood through the first aperture via capillary action, waiting for a time sufficient for at least a portion of the red blood cells to settle within the first open volume of the microstructures, and applying pressure to the device, thereby causing some of the initial volume of blood, from which at least some of the red blood cells have been retained within the first open volume of the microstructures, to flow out of the device.