Abstract: A method of controlling thermal transfer in a perfusion system heat exchanger of an extracorporeal fluid treatment device for conditioning an extracorporeal patient fluid for administration to a patient comprises a step of providing a perfusion system heat exchanger, wherein the perfusion system heat exchanger comprises a first fluid passage for a liquid heat transfer medium and a second fluid passage for the extracorporeal patient fluid to be temperature-controlled via exchange of thermal energy with the heat transfer medium, and a step of providing the heat transfer medium through the first fluid passage. The heat transfer medium comprises a component with anti-microbial properties, such as glycol. The provision of antimicrobial fluid reduces the risk of microbe contamination of the extracorporeal fluid, and hence the risk of clinical complications.

Abstract: An exhaust gas flow control system for an oxygenator of an extracorporeal ventilation system connected to an oxygenation gas supply line and to an exhaust line for removal of exhaust gas comprises a flow control path, a pressure control path, an exhaust flow regulator responsive to the controller, and an exhaust gas pressure regulator responsive to a controller configured to maintain a pre-determined pressure level in the exhaust line. This provides a better degree of control over the pressure across the oxygenator from oxygenation gas inlet to exhaust.

Abstract: A clamping mechanism (30) for clamping a flexible tube comprises two rotatable bobbins (22, 32), each with a tube-engaging surface portion (24) defining boundaries of a free space through which a tube may extend. The shape of the tube-engaging surface portion (24) changes around the bobbin circumference, such that axial rotation of the bobbins (22, 32) reduces the free space and thereby squeezes the tube. This allows the flow through the tube to be altered dependent on the rotation of the bobbins.

Abstract: A cardioplegic agent delivery system comprises a supply reservoir (40) for a cardioplegic agent carrier fluid, a delivery channel from the supply reservoir (40) to an outlet (48), and a pump (50) to flow the carrier liquid in the delivery channel above a minimum driving pressure. The supply reservoir (40) is configured to hold carrier fluid below the minimum driving pressure. The pump (50) is a centrifugal pump configured to receive carrier fluid from the supply reservoir (40) and to flow the carrier fluid to the outlet (48) at a flow rate and above the minimum driving pressure for the delivery of cardioplegic agent. This allows cardioplegia delivery to be managed better.

Abstract: A control system in a blood line (12) of a cardiopulmonary bypass perfusion system (1) comprises a flow sensor (26) to determine a flow value indicative of the flow rate, a controller configured to process the flow value, and an adjustable restriction (28) responsive to the controller, to reduce the flow rate in the venous blood line (12) to maintain a flow rate to the venous blood reservoir that does not exceed a restriction threshold. As the adjustable restriction (28) is responsive to the flow sensor (26), this provides a closed loop control mechanism that avoids restricting the blood line (12) of the perfusion system (1) more than intended.

Abstract: A control system controlling the blood flow rate in a blood supply system (1) in which a pump (18) transports blood from a reservoir (10) toward multiple outlets (30, 26, 26a) of which one or more outlets are openable to permit flow and closable to block flow, wherein the control system comprises a monitoring arrangement (22, 32, 32a) to determine the flow rate through a first outlet (30), and a controller responsive to the monitoring arrangement and controlling the pump (18) to maintain the flow rate through the first outlet (30) at a pre-determined level. This allows a flow rate through the first outlet to be maintained independently of any active blood diversions.

Abstract: A control system for controlling a quantity of blood in a blood reservoir (10) of a perfusion system supplied by a venous line (V), wherein a pump (20) circulates blood from the blood reservoir (10) through an outgoing line (A), comprises a venous flow sensor (22) to measure a venous blood flow rate, an outlet flow sensor (24) to measure an outgoing blood flow rate, and a controller to control the pump (20) to prevent the outgoing blood flow rate from exceeding the venous blood flow rate. Thereby, a decrease of blood in the blood reservoir (10) can be arrested.

Abstract: A flow control system of a clinical perfusion system comprises flow control devices 110, such as pumps, valves and/or clamps, capable of controlling a fluid flow rate according to flow rate parameters from the flow control system. The flow control system comprises an indicator arrangement including a device indicator 122a, 122b on each flow control device 110 capable of providing a plurality of indications. The device indicators 122a, 122b are controllable by the flow control system to indicate an active condition of the flow control device 110 independently of the flow rate parameters. This allows the indication provided by the device indicator 122a, 122b to be adjusted for different clinical environments, and to provide colour indications that match the colour range discernible by users affected by colour vision deficiency.

Abstract: A blood gas analysis method (100) is provided for determining the partial pressure of oxygen of arterial blood exiting an oxygenator, wherein the oxygenator generates arterial blood by exposing venous blood to an oxygenation gas and releases excess oxygenation gas as exhaust gas. The method (100) comprises a step (140) of determining an estimate of the partial pressure of oxygen in the exhaust gas, a step (150) of determining the blood oxygen uptake in the oxygenator, and a step (160) of determining the partial pressure of oxygen in the arterial blood by adjusting the estimate using the blood oxygen uptake value. Used in a clinical setting, the method (100) allows a more accurate output of the partial pressure of oxygen in the arterial blood to be provided, which facilitates oxygenator operation.

Abstract: A control system controlling the line pressure in a blood supply system (1) in which a pump (14) pumps blood from a reservoir (10) via a primary passage (18) toward a plurality of outlets (16, 26, 26a), wherein one or more outlets are openable to permit flow and closable to block flow, said control system comprises a monitoring arrangement to determine a line pressure in the primary passage, and a controller responsive to the monitoring arrangement and controlling the pump (14) to maintain the line pressure in the primary passage (18) above a pre-set level. The control system practically eliminates the risk of a momentary reduction in blood supply line pressure when an outlet is opened.

Abstract: A clamp arrangement for retaining a flexible tube (18) during operation of a roller pump (10) for pumping fluid, the clamp arrangement comprising a pair of rotatable bobbins (24A, 24B, 26A, 26B) mounted adjacent to each other. Each bobbin (24A, 24B, 26A, 26B) has a tapered groove (30), formed partially around a cylindrical surface of the bobbin (24A, 24B, 26A, 26B), and counter rotation of the bobbins (24A, 24B, 26A, 26B) clamps the tube 18 between the bobbins (24A, 24B, 26A, 26B) in the tapered grooves (30). The clamp arrangement allows tubes of different shapes and diameters to be securely held without overly deforming the tube.

Abstract: A cardioplegic agent delivery system comprises a syringe pump for providing cardioplegic agent into a carrier fluid of a perfusion system, a flow sensor for sensing a flow of the carrier fluid, and an interlock responsive to the flow sensor. The interlock prevents operation of the syringe pump in the absence of carrier fluid flow sensed by the flow sensor. This provides increased safety in a cardioplegic agent delivery system.

Abstract: A control system controlling blood gas values in blood processed by an oxygenator, wherein the oxygenator generates arterial blood by exposing venous blood to oxygen from an oxygenation gas supply, comprises a monitoring arrangement to determine a level of the blood gas values in the arterial blood and a controller that is responsive to the monitoring arrangement and configured to control parameters of the oxygenation gas supply to the oxygenator. This allows the blood gas values to be adjusted toward a pre-determined level.

Abstract: An oxygenation system for a ventilation system comprises an inlet for receiving oxygenation gas at an oxygenation gas flow rate into an oxygenator, and an exhaust gas remover to remove exhaust gas at an exhaust gas flow rate from the oxygenator, and one or more flow controllers for controlling the exhaust gas flow rate relative to the oxygenation gas flow rate. This allows the amount of total gas entering the oxygenator and the amount of total gas removed from the oxygenator to be controlled with greater accuracy.