Role of preoperative hemodynamic monitoring in intraoperative fluid management

In this study the hemodynamic factors which contribute to postoperative mortality and morbidity were evaluated in 41 patients. Preoperative data were prospectively collected over a 5-year period. The patients underwent vascular and general surgical operative procedures. Among them, 23 patients had minor or no postoperative complications (group 1) and 18 patients suffered serious complications or died (group 2). Preoperative cardiac function was better in group 1, but both groups achieved their best cardiac index (CI) with fluids or pharmacologic manipulation preoperatively. Group 2 patients had longer operations, more blood loss, and were significantly hypovolemic postoperatively as indicated by lower pulmonary arterial wedge pressure (PAWP) and CI in comparison to the best preoperative values. When postoperative PAWP was higher than or within 3 mm Hg of the best preoperative level, complication rate was 14 per cent (3 of 21). In 15 of the 19 or 79 per cent of the patients, postoperative complications developed when PAWP decreased by 4 mm Hg or more. The difference in complications was significant (P less than 0.01). However, commonly measured parameters such as the amount of fluid infused, urine output, immediate postoperative heart rate, blood pressure, central venous pressure, and hemoglobin failed to reveal hemodynamically significant hypovolemia or lacticacidemia in group 2. The authors were unable to demonstrate a reduction in mortality or morbidity in group 2 patients in whom serious technical operative difficulties were also encountered.