# US 5,215,519 A · Autotransfusion membrane system with means for providing reverse filtration > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,215,519 A - Document ID: US5215519A - Status: Granted - Kind: A - Application number: 07/730,705 - Filed: 1991-07-16 - Granted: 1993-06-01 - Earliest claimed: 1990-03-07 - Inventors: U. Ramakrishna Shettigar - Web page: https://patentgrep.com/patent/US5215519A ## CPC - A61M 1/3627: {Degassing devices; Buffer reservoirs; Drip chambers; Blood filters} - A61M 1/02: Blood transfusion apparatus (blood infusion by syringes A61M5/14) - A61M 1/34: Filtering material out of the blood by passing it through a membrane, i.e. hemofiltration or diafiltration - A61M 1/3403: {Regulation parameters} - A61M 1/3451: {the difference in weight between both ultra-filtrate and substitution reservoir being used as control signal} - A61M 1/3603: {in the same direction} - A61M 1/3604: {in opposite directions} - A61M 1/3612: {after treatment} - A61M 1/3692: {Washing or rinsing blood or blood constituents} - A61M 1/631: {Emptying the suction container without interrupting suction} - A61M 1/3626: {Gas bubble detectors} - A61M 1/3639: {Blood pressure control, pressure transducers specially adapted therefor} - A61M 1/3669: {Electrical impedance measurement of body fluids; transducers specially adapted therefor} - A61M 2205/3331: Pressure; Flow - A61M 2205/3375: Acoustical, e.g. ultrasonic, measuring means - A61M 2205/3382: Upper level detectors - A61M 2205/3386: Low level detectors - A61M 2205/3389: Continuous level detection (A61M2205/3393 takes precedence) - A61M 2205/3393: by weighing the reservoir - A61M 2205/75: with filters - A61M 2205/7554: with means for unclogging or regenerating filters - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} ## Abstract An apparatus for recycling autologous blood from a patient for reinfusion back to the patient comprising suction means, means for admixing aspirated blood with a washing fluid, filtering means for filtering the admixture through an emboli filter, monitoring means for measuring the blood component levels or hematocrit in the filtered blood, filtration means for removing excess fluid and particulates from the blood, and reinfusion means is disclosed. The apparatus operates in three different modes--idling, filtration and reinfusion--in response to specified conditions. Embodiments for use during surgery for on-line purification and reinfusion on a real time basis are disclosed along with embodiments for use postsurgically when the wound site is closed. Means for performing reverse filtration in the membrane filter are also included for maintaining a consistent level of filtration through the membrane filter. ## Claims ### Claim 1 Apparatus for treating autologous blood taken from a patient for reinfusion to the patient comprising: suction means for aspirating blood from a wound site; conduit means for conducting said aspirated blood from said suction means; washing fluid retainer means for retaining washing fluid for admixing with said aspirated blood, said washing fluid retainer means being in fluid communication with said conduit means; first filter means for removing emboli and large particulates from said aspirated blood, said first filter means being connected to said conduit means; vacuum connector means associated with said first filter means for attachment to a source of vacuum; filter casing means for enclosing said first filter means therein; detection means associated with said filter casing means for detecting blood levels within said casing; second filter means for filtering excess fluids and impurities from said blood, said second filter means being in fluid communication with said first filter means; filtrate container means associated with said second filter means for containing said excess fluids and particulates filtered from said blood by said second filter means; structure means connectable to said second filter means for providing movement of fluid through said second filter means to effect reverse filtration relative to said second filter means; reinfusion means in fluid communication with said second filter means for reinfusing filtered blood to said patient; and monitor means positioned proximate said reinfusion means for monitoring blood component levels. ### Claim 2 (depends on 1) The apparatus of claim 1 wherein said second filter means includes a circulation chamber and a filtration chamber, said circulation chamber being in fluid communication with said first filter means, and said filtration chamber being in fluid communication with said structure means for providing reverse filtration. ### Claim 3 (depends on 2) The apparatus of claim 2 wherein said structure means for providing reverse filtration includes fluid retainer means in fluid communication with said filtration chamber for supplying fluid to said filtration chamber, and clamp means associated with said fluid retainer means for selectively preventing said fluid from being supplied to said filtration chamber. ### Claim 4 (depends on 2) The apparatus of claim 2 further comprising means for communicating blood from said first filter means to said second filter means and from said second filter means to said first filter means, said apparatus further including first mechanical means for urging the movement of blood within said means for communicating blood. ### Claim 5 (depends on 4) The apparatus of claim 4 further comprising clamp means connected to said means for communicating blood between said second and first filter means, said clamp means selectively preventing said blood from being communicated between said second and said first filter means through said means for communicating blood. ### Claim 6 (depends on 5) The apparatus of claim 5 wherein said clamp means connected to said means for communicating blood, said detection means, said monitoring means and said first mechanical means are all in electromechanical communication with each other. ### Claim 7 (depends on 6) The apparatus of claim 6 further comprising a third filter associated with said reinfusion means, blood level detection means associated with said third filter for detecting the presence of emboli, and clamp means associated with said reinfusion means for selectively preventing reinfusion of blood to said patient, said clamp means being in electromechanical communication with said clamp means connected to said means for communicating blood, said detection means, said monitoring means, said blood level detection means and said first mechanical means. ### Claim 8 (depends on 4) The apparatus of claim 4 further comprising a third filter associated with said reinfusion means and blood level detection means associated with said third filter for detecting the presence of emboli. ### Claim 9 (depends on 8) The apparatus of claim 8 further comprising second mechanical means associated with said reinfusion means for urging blood therethrough, said second mechanical means being in electromechanical communication with said first mechanical means, said monitor means, said detection means and said blood level detection means. ### Claim 10 (depends on 8) The apparatus of claim 8 wherein said monitor means is positioned proximate said second filter means. ### Claim 11 (depends on 2) The apparatus of claim 2 wherein said first filter means and said second filter means are integrally joined and positioned within said filter casing means. ### Claim 12 (depends on 11) The apparatus of claim 11 further comprising mechanical means associated with said reinfusion means for urging said blood therethrough. ### Claim 13 (depends on 12) The apparatus of claim 12 wherein said structure means for providing reverse filtration includes fluid retainer means in fluid communication with said filtration chamber for supplying fluid to said filtration chamber, and clamp means associated with said fluid retainer means for selectively preventing said fluid from being supplied to said filtration chamber. ### Claim 14 (depends on 13) The apparatus of claim 13 wherein said fluid retainer means is said washing fluid retainer means, and wherein said apparatus further includes an afferent line connected to said washing fluid retainer means to provide fluid communication with said filtration chamber of said second filter means. ### Claim 15 (depends on 13) The apparatus of claim 13 further comprising mechanical means for urging fluid from said fluid retainer means. ### Claim 16 (depends on 15) The apparatus of claim 15 further including a filtrate conduit interconnected between said filtration chamber and said filtrate retainer means for conducting filtrate therebetween, and clamp means associated with said filtrate conduit for selectively preventing filtrate from flowing through said filtrate conduit. ### Claim 17 (depends on 16) The apparatus of claim 16 wherein said mechanical means is also associated with said filtrate conduit for urging filtrate along said filtrate conduit. ### Claim 18 (depends on 1) The apparatus of claim 1 further comprising vacuum regulation means associated with said vacuum source for regulating the amount of negative pressure provided by said vacuum source to said apparatus. ### Claim 19 An apparatus for treating autologous blood taken from a patient for reinfusion to the patient comprising: suction means for aspirating blood from a wound site; first conduit means for conducting said aspirated blood from said suction means; washing fluid retainer means for retaining washing fluid for admixing with said aspirated blood; second conduit means interconnected between said washing fluid retainer means and said first conduit for conducting washing fluid therebetween; first filter means for removing emboli and large particulates from said aspirated blood, said first filter means being connected to said first conduit means; filter casing means for enclosing said first filter means therein; vacuum connector means associated with said first filter means for attaching a source of vacuum thereto; reservoir means associated with said filter casing means for collecting filtered blood from said first filter means; second filter means for filtering excess fluids and particulates from said blood; third conduit means interconnected between said reservoir means and said second filter means for conducting blood therebetween; fourth conduit means interconnected between said second filter and said reservoir for conducting filtered blood therebetween; filtrate container means in fluid communication with said second filter means for containing said excess fluids and particulates filtered from said blood by said second filter means; structure means connectable to said second filter means for providing movement of fluid through said second filter means to effect reverse filtration relative to said second filter means; fifth conduit means interconnected between said second filter means and said filtrate container means for conducting filtrate therethrough; and reinfusion means associated with said blood collection means for reinfusing purified blood to the patient. ### Claim 20 (depends on 19) The apparatus of claim 19 wherein said washing fluid retainer means is positioned below said relative height of said suction means. ### Claim 21 (depends on 20) The apparatus of claim 20 wherein said second filter includes a circulation chamber and a filtration chamber, said circulation chamber being in fluid communication with said first filter means, and said filtration chamber being in fluid communication with said structure means for providing reverse filtration. ### Claim 22 (depends on 21) The apparatus of claim 21 wherein said structure means for providing reverse filtration includes fluid retainer means in fluid communication with said filtration chamber for supplying fluid to said filtration chamber, and clamp means associated with said fluid retainer means for selectively preventing said fluid from being supplied to said filtration chamber. ### Claim 23 (depends on 22) The apparatus of claim 22 further comprising detection means associated with said filter casing means for detecting blood levels therein and monitor means associated with said reinfusion means for monitoring blood cellular component levels. ### Claim 24 A method of obtaining and treating autologous blood for reinfusion into a patient comprising: providing apparatus for treating autologous blood comprising: aspiration means for aspirating blood from a patient; a source of washing fluid, first filter means for removing emboli and particulates from said blood; a source of vacuum associated with said first filter means; second filter means for removing excess fluid and particulates from said blood; structure means for providing movement of fluid through said second filter to effect reverse filtration therethrough; monitoring means for evaluating blood component levels; and reinfusion means; aspirating blood from said patient using said aspiration means; admixing said blood with washing fluid from said source of washing fluid; filtering said admixture of blood and washing fluid through said first filter means to remove emboli and particulates; filtering said admixture through said second filter means to remove particulates and excess fluid; selectively providing fluid to said second filter means from said structure means for providing reverse filtration to effect intermittent reverse filtration; monitoring said filtered blood cellular volume fraction in said blood; and reinfusing said filtered blood into said patient. ### Claim 25 (depends on 24) The method according to claim 24 further comprising filtering said blood after monitoring said filtered blood and prior to reinfusing said filtered blood into said patient.