A recovery model of partial cardiopulmonary bypass in the rat

This study was undertaken to develop a recovery model of cardiopulmonary bypass (CPB) in rats. Twenty male Wistar rats (475-550 g) were anaesthetized, mechanically ventilated and the femoral vessels cannulated. The extracorporeal circulation circuit comprised a roller pump, a venous reservoir and a modified Capiox 308 paediatric membrane oxygenator. Priming consisted of 20 ml of fresh homologous blood and 15 ml of colloid. Anticoagulation was achieved with heparin (500 IU/kg). Blood gas analysis, blood pressure monitoring and survival studies were performed in CPB ( n=10) and Sham ( n=10) rats.

Partial CPB was always easily established and was conducted at a flow rate of 100 ml/kg/min for 90 min. Blood gas analysis and blood pressure data did not differ between the two groups. All CPB rats survived and the 3-week follow-up period remained uneventful.

The rat model of CPB was easy to perform and was associated with excellent survival. This recovery model should allow us to study the pathophysiological processes underlying post-CPB multiple organ dysfunction.