Abstract: The present invention is a blood separation system that is fully mechanized to collect blood from a patient, separate waste portions of the blood, wash the blood, and redirect the usable portions to a device for reinjecting the usable portions into the patient. The present invention prevents accidental activation of an improper operation that could cause harm to a patient or a shut down of the system by requiring confirmation of each step by an operator. The invention provides screen displays with detailed setup instructions, eliminating the need for secondary documentation that might not be allowed in a surgical environment. The invention also instructs the operator at the appropriate times to do certain manual steps such as opening and closing clamps. Since the opening and closing of clamps is a highly critical operation, confirmation of these steps is also required.

Abstract: The present invention is a centrifuge bowl housing and cover latch suitable for use in a blood separation system. The housing is mounted on shock absorbers to minimize transmission of vibrations from the centrifuge. The housing is configured to retain spilled liquids, efficiently collect the spilled liquids, drain liquids away from the drive means, and drain liquids out of a drain port to a collection container. The housing has a transparent cover that opens to allow loading of centrifuge bowls into the housing. The cover is a shatter resistant material and when closed, seals the top of the housing, retaining blood components and flying pieces of a centrifuge bowl if the bowl breaks. The cover has a latch that prevents the centrifuge from spinning when the cover is open and prevents opening of the cover when the centrifuge is spinning.

Abstract: A system for securing a blood separator bowl in an autotransfusion machine includes a split ring or collar adapted to grip an enlarged cap on the base of the bowl and a clamp assembly for moving the collar between retracted and expanded positions. In the retracted position, the clamp assembly includes both an overcenter lock system for securing the collar in the retracted position and a backup auxiliary lock in the event of failure. The system further provides for centering the separator bowl on its axis of rotation to prevent undue vibration.

Abstract: The disposable flexible pouch for collecting and filtering blood has two inner chambers separated from each other by a filtering screen (11), a first chamber being connected to the outside by an outlet opening for the filtered blood and a second chamber being connected to the outside by an inlet opening for the blood to be processed. The pouch is formed from two superposed walls (1, 2) made of a flexible plastic material and bonded together by welding of their respective peripheral edges (3). The inlet and the outlet openings for the blood, as well as an outlet opening (5) for the suction air provided with a bacterial filter, are all made in the same wall (2) forming the pouch and the filtering screen (11) having a lower surface at the surface of this same wall (2) cooperates with the inner face thereof to form several compartments communicating with one another and forming the second chamber, so that the retention volume is reduced.

Abstract: A pinch clamp finding a primary use in an autotransfusion machine includes a hollow clamp head having a closed upper end and an open lower end reciprocally receiving a piston. A lateral groove is established in the clamp head so that a deformable tube can be received in the clamp head passing through the hollow interior thereof. The piston is reciprocally moved within the clamp head so as to selectively pinch the tube between the piston head and the closed end of the clamp head. The piston is positively reciprocated by cam followers on a piston rod with the cam followers riding in closed cam tracks in adjacent cam wheels on opposite sides of the piston. The cam wheels are mounted on a crankshaft which is selectively driven by power means.

Abstract: A peristaltic pump and tube body system disclosed includes a pump housing, a pump rotor rotatably mounted in the housing, and a motor for driving the rotor. The housing has a pair of opposed side walls hinged and releasably latched to the housing whereby insertion and removal of a pump tube is facilitated. The rotor has two rollers disposed at 180 degrees to one another together with opposed rigid bearing surfaces inside the housing which squeeze the latch to produce a pumping action when the rotor is rotated in either direction.

Abstract: An intravenous fiber membrane oxygenator is disclosed in several embodiments wherein the fibers either run at a transverse angle relative to the longitudinal axis of the oxygenator and/or are of a reduced length to optimize the gas transfer efficiency of the oxygenator. Various helical or spiral wraps of fibers are disclosed. One embodiment utilizes two sets of longitudinally extending fibers wherein the oxygen gas is moved in opposite directions from a central location of the oxygenator.

Abstract: An inflatable tourniquet cuff includes an inflatable bladder having an outer layer with a predetermined thickness and an inner layer with a thickness that is less than the predetermined thickness of the outer layer. An opening in the bladder allows for the inflation and deflation of the bladder. A fastener system attached to the bladder releasably secures the bladder about a patient's limb so that the thin inner layer is positioned adjacent the patient's skin. The thin layer is relatively flexible in comparison to the thick outer layer and thus expands to a greater degree than the outer layer upon inflation of the bladder.

Abstract: A gas transfer apparatus readily adapted for oxygenating blood includes a housing with a hollow internal chamber having a fiber mat consisting of two sets of intermingled hollow fibers with one set of fibers having micropores formed in the walls thereof and the other set having solid liquid impermeable walls. The housing for the apparatus is designed such that the blood being processed passes substantially uniformly across the entire cross section of the fiber mat whereby a treating gas such as oxygen being directed through the microporous fibers can be diffused into the oxygen deficient blood while excess CO.sub.2 in the blood can cross diffuse into the interior of the fiber and be removed from the apparatus. Simultaneously with the cross diffusion of gas between the microporous fibers and the blood, a thermal conducting fluid such as water is passed through the solid walled fibers to maintain or regulate the temperature of the blood in the apparatus.

Abstract: A blood collection reservoir and filter device includes a generally cylindrical housing and an internal filter medium with the filter medium being retained in spaced relationship from the side wall of the housing so that blood can pass through the filter in a non-traumatized manner and flow smoothly onto a dispersion plate for cascading delivery to the internal surface of the side wall of the housing where it can flow in a non-traumatic manner to an outlet in the bottom wall of the housing. The filter medium includes a defoaming filter layer and a particulate filter layer so that blood removed from a surgical wound can be defoamed and filtered within the device. The filter is elevated within the housing to provide a relatively large temporary storage area where blood can be retained in non-contact with the filter.

Abstract: A tube clamp for dependably occluding the flow of fluid through a deformable tube includes a pair of pin members mounted on a supporting surface adjacent to a pivotal body that includes an edge portion adapted to be pivoted into the space between the pin members to pinch the tube against the pin members, thereby occluding the flow of fluid through the tube.

Abstract: A blood filter device for separating gas bubbles from a flow of blood includes a filter medium in a lower body portion of the device through which the blood must flow before being directed through an outlet tube. An upper cap sealed to the top of the lower body portion includes a blood inlet tube into which a conical dispersion plate is projected so as to decrease the rate of flow of the blood. The rate of flow further decreases as it enters a debubbling chamber in the cap. A top wall of the cap defines a sloped and arched channel around the inlet tube adapted to direct released gas toward a vent tube at the uppermost extent of the sloped top wall.

Abstract: A method of cleaning red blood cells which have been separated from undesirable components of blood in a centrifugal separating chamber includes the steps of pulsating a washing solution through the red blood cells in an alternating high flow rate/low flow rate sequence so as to alternately agitate the red cells for optimal cleaning and stabilize the red cells to prevent a flushing of the cells from the separation chamber.

Abstract: An electronic measuring device utilizes multiple different transducers for supplying signals exhibiting predetermined and typically nonlinear relationships to the multiple input variables sensed by the transducers. The measuring device includes a microcomputer containing stored linearizing information therein relating to the predetermined nonlinear relationship of the signals supplied by the transducers and the variables sensed by the transducers. The microcomputer linearizes each of the signals supplied by the transducers and thereby obtains highly accurate signals indicative of the variables sensed. Depending upon the ultimate determination to be obtained by the device, the linearized signals representative of the input variables may be employed in a polynomial equation calculation conducted by the computer to obtain the output determination.

Abstract: The temperature within a freezer case or refrigeration compartment is operatively determined and controlled by a control system employing a microcomputer which operatively controls a refrigeration system associated with the freezer case. A sensing element is operatively connected to the microcomputer for supplying a signal representative of the freezer compartment temperature. Temperature selector switches establish upper and lower limits of a desired range of temperatures for the freezer case and another selector switch establishes an alarm condition temperature limit. The microcomputer follows a program of comparing the compartment temperature to the upper limit, the lower limit and the alarm condition limit. During normal operation, the microcomputer also controls a refrigerant valve to regulate the compartment temperature within the desired range. If the compartment temperature elevates to the alarm condition limit, the microcomputer energizes a first alarm.

Abstract: A digital thermometer uses a microprocessor computer containing stored information relating to the response characteristics of a transducer to supply a measurement of temperature. The transducer is preferably a thermistor whose resistance varies in a predetermined and nonlinear relation to its temperature. The microprocessor computer includes a read-only memory which has been preprogrammed with piece-wise linearized information approximating the nonlinear relation of resistance and temperature of the thermistor. A current source develops a voltage across the thermistor which is related to the temperature of the thermistor. The voltage across the thermistor is converted into a digital signal, and the digital signal is related to the piece-wise linearized information stored. The temperature equivalent is calculated from a first order algebraic equation determined by the relationship of the digital signal to the stored information.

Abstract: A display unit having a plurality of light emitting segments is directly attached to a circuit board, thereby avoiding use of a separate encapsulated display device. The circuit board is provided with a plurality of electrical conductors permanently attached to its component mounting surface. Electrically conductive leads extend between the light emitting segments of the display unit and the electrical conductors attached to the circuit board. The display unit includes a base supporting member to which the light emitting segments are attached in a desired configuration. The base member is preferably glued with an electrically conductive glue to an electrical conductor attached to the circuit board, thereby simultaneously physically connecting the base member directly and permanently to the circuit board and electrically connecting a common terminal of the light emitting segments to the electrical conductor on the circuit board.