Haemodynamics and 'optimal' hydration in aortic cross clamping.

The effect of optimal hydration on haemodynamics and renal function during infrarenal aortic cross clamping was studied in 26 consecutive patients operated on because of an infrarenal aortic aneurysm. The patients were randomly divided over two groups. The patients of group B (n = 13) were optimally hydrated before the operation. The Starling curve was used as standard. Patients of group A (n = 13) served as control. The pre-operative and postoperative renal functions of both groups were compared, as were the haemodynamic parameters. The haemodynamic parameters were measured at five minutes intervals during the entire procedure. During aortic clamping the heart rate was significantly lower in patients of group B, indicating a lower myocardial oxygen consumption. Neither the haemodynamic parameters nor the renal function showed other beneficial effects on optimal hydration.