The effect of hemodynamic factors on cardiac performance following open heart surgery.

Sixteen patients who had undergone open heart surgery were studied in order to determine the factors influencing cardiac performance in the postoperative period. Hemodynamic influences during and following cardiopulmonary bypass were found to be more important than the preoperative cardiac function. The flow rate used during cardiopulmonary bypass had a pronounced influence on the post-operative cardiac performance. A low flow can result in the development of vasoconstriction postoperative with an increased chance of low cardiac output. A high flow during bypass is recommended, and in the postoperative period vasoconstriction must be treated vigorously to forecome low cardiac output.