A SELF-REGULATING PUMP CHAMBER FOR STANDARD ROLLER PUMPS

THE ROLLER PUMP, USED TO PUMP BLOOD FLOW DURING CARDIOPULMONARY BYPASS AND TO PROVIDE LONG-TERM CIRCULATORY SUPPORT, IS A CONSTANT-BLOOD-FLOW DEVICE. IT MAINTAINS CONSTANT FLOW INDEPENTLY OF THE CLINICALLY EXPECTED CHANGES IN INLET PRESSURES. A DECREASE IN BLOOD SUPPLY TO THE INLET OF THE PUMP WITHOUT A CONCOMITANT DECREASE IN PUMP SPEED CAN CAUSE EXCESSIVE SUCTION LEADING TO AIR EMBOLISM, THROMBOSIS, AND DAMAGE BY THE "VENOUS" CANNULA TO THE VESSEL'S INTIMA OR, WITH A BUBBLE OXYGENATOR, THE EMPTYING OF THE OXYGENATOR, PUMPING AIR TO THE PATIENT. THE PURPOSE OF THIS RESEARCH IS TO DESIGN, FABRICATE, AND EVALUATE A NEW, INNOVATIVE DISPOSABLE PUMP CHAMBER FOR THE STANDARD ROLLER PUMP THAT SELF-CONTROLS THE PUMP FLOW AS A FUNCTION OF INLET OR FILLING PRESSURE, MUCH LIKE THE NATURALHEART. THE PUMP CHAMBER CONSISTS OF AN EASILY COLLAPSIBLE THIN-WALL TUBING (TWT) HOUSED AND SEALED IN A STANDARD PUMP TUBING. THE INNER TWT SERVES TO PUMP BLOOD AND THE OUTER TUBING SERVES AS A MECHANICAL SUPPORT AND CONTROLLED PRESSURE ENVIRONMENT FOR THE TWT. THIS PUMP CHAMBER CAN PROVIDE ADDITIONAL SAFETY DURING OPEN HEART SURGERY AND ALSOFUNCTION AS AN INEXPENSIVE, SELF-CONTROLLING MECHANISM FOR LONG-TERM CIRCULATORY SUPPORT.