Transfusion-free cardiopulmonary bypass in Jehovah's Witness patients weighing less than 5 kg.

Performing cardiac surgery on pediatric Jehovah's Witness patients is a great challenge for the surgical team and especially for the perfusionist. Jehovah's Witnesses reject blood transfusions on the grounds of their literal interpretation of passages of the Bible. In accordance with this belief, Jehovah's Witnesses feel that it is also forbidden to retransfuse autologous blood that has been separated from their own circulatory system. We report the use of cardiopulmonary bypass (CPB) during open-heart surgery in three infants with a body weight of 4.5 kg, 3.5 kg, and 3.1 kg, respectively, without transfusion of blood components. A small-volume CPB circuit with a priming volume of 200 mL, including the arterial line filter, was designed to decrease the degree of hemodilution. A dedicated pediatric heart lung machine console with remote pump heads and intensive blood conservation efforts allowed the operation without the use of donor blood. The CPB circuits were primed with crystalloid solution only. The procedures were performed in normothermia or in moderate hypothermia. Pre-CPB hemoglobin levels were 10.8 g/dL, 10.6 g/dL, and 8.5 g/dL. The hemoglobin concentrations measured during CPB ranged from 5.9 to 6.5 g/dL, 6.4 to 6.8 g/dL, and 5.5 to 5.9 g/dL, respectively. The patients did not receive any blood or blood products during their entire hospital stay.

Perfusion technique for nonhaemic cardiopulmonary bypass prime in neonates and infants under 6 kg body weight.

BACKGROUND: Cardiopulmonary bypass (CPB) in neonates and infants is associated with significant haemodilution when priming of the CPB circuit is accomplished without transfusion of homologous blood components. The degree of haemodilution and, thus, the requirements for blood transfusion may be reduced when the CPB circuit is miniaturized without compromising patient safety. METHOD: Between January 2002 and October 2003, selected neonates and small infants were operated on using a nonhaemic prime extracorporeal circuit. CPB priming volume could be reduced from 300 mL to 190 mL by using a dedicated neonatal CPB console with mast-mounted roller pump heads. Reduction of priming volume resulted from shortening of all CPB lines to the minimum, downsizing of all CPB lines, exclusion of unused CPB components, use of vacuum-assisted venous drainage and from close co-operation between the perfusionist, cardiac surgeon and anaesthesiologist. The reduction in priming volume was achieved without eliminating the arterial line filter as safety device. RESULTS: A total of nine patients weighing between 3.2 and 5.9 kg (mean 4.7 kg) and with a body surface area of 0.22-0.35 m2 (mean 0.29 m2) were operated on with the use of the modified neonatal CPB circuit and a nonhaemic prime. Bypass time varied from 38 to 167 min (mean 96 min). The mean haematocrit on CPB was 22.5% with a range of 17-29%. The postoperative course of all patients was uneventful. CONCLUSION: A significant reduction in CPB priming volume makes nonhaemic prime CPB in neonates and small infants undergoing complex repair of congenital heart defects possible.

Reduction of microemboli count in the priming fluid of cardiopulmonary bypass circuits.

Microemboli may impair cognitive function in patients undergoing heart surgery. Prebypass filtration has been shown to reduce particle load in the cardiopulmonary bypass (CPB) priming fluid. This study was performed to detect the embolic load of CPB priming fluid, to determine the efficacy of a 0.2 microm prebypass filter (PBF) in reducing emboli in the range of 0.1-5 microm and to provide guidelines for the handling of the device. A total of 12 CPB circuits were tested in two groups, using a laser light scattering particle counter, sensitive to microemboli in the range of 0.1-5 microm. In control group A, priming fluid before administration to the CPB circuit was analyzed. Group B circuits contained microporous membrane oxygenators (N = 5); group C consisted of CPB circuits with excluded membrane oxygenators (N = 7). When group A was compared to groups B and C, significantly more microemboli were found in the categories 0.2 microm, 0.5 microm, 0.8 microm for both groups B and C (p < .05). Group C circuits had higher microemboli counts in the categories 1.5 microm and 3 microm (p < .05) when compared to group B. Microemboli bigger than 0.2 microm could be eliminated after 2 min of prebypass filtration with a CPB flow of 5 L/min. The number of microemboli smaller than 0.2 microm was reduced substantially. Small microemboli with a size of 0.1 microm originate mainly from the priming solution. Microemboli in the range of 0.2 microm, 0.5 microm, and 0.8 microm originate mainly from the CBP circuit. In circuits with bypassed membrane oxygenators, a higher microemboli count in the range of 1.5 microm and 3 microm may be explained by a possible filtering capacity of membrane oxygenators. The 0.2 microm PBF is an effective tool to reduce the particle load in the CPB priming fluid.