The Annals of Thoracic Surgery, Vol 35, 380-385, Copyright © 1983 by The Society of Thoracic Surgeons
Calculated preoperative mean left atrial pressure as a guide to volume load at the termination of aortocoronary bypass operation
DA Goor, R Mohr, J Lavee and A Smolinsky
The routine use of an arbitrary fixed left atrial (LA) pressure during
volume load after aortocoronary bypass operation was compared with use of
an individualized postoperative target LA pressure according to a
calculated preoperative LA pressure in two groups of consecutive patients.
The preoperative LA pressure of each patient was calculated from the
preoperative left ventricular end-diastolic pressure (LVEDP) by the
formula: mean LA pressure = 1.16 x LVEDP - 8.53. Left atrial pressure, mean
arterial pressure, mean right atrial pressure, and cardiac output were
measured simultaneously on arrival at the intensive care unit and 60
minutes later. Cardiac index (CI) and systemic vascular resistance (SVR)
were calculated from the variables already mentioned. Results indicated a
significantly higher CI and significantly lower SVR in patients in whom
volume load was aimed at the calculated preoperative LA pressure. It was
concluded that the optimal postoperative LA pressure is specific for each
patient and depends on the preoperative LVEDP.