[The value of blood lactate determination in the postoperative phase]

The aim of this study was to investigate whether the measurement of blood lactate in the early postoperative period would be useful for an assessment of the postoperative course. For the determination of a reference curve, the lactate concentration was measured in 10 patients (control group) with uncomplicated courses of the operation which lasted for up to two hours. The investigation group included 111 patients with complicated courses of the operation and/or a duration of the operation of more than 2 hours. The reference value of lactate was 1.3 mmol/l on the average. Lactate values above 2.5 mmol/l were considered as pathological values. In spite of the high physiological range of variations of the blood lactate concentration and many factors which influenced this value, it could be shown that the blood lactate concentration enabled a good prognostic assessment of the course of the early postoperative period in intensive care patients. Intraoperative complications were followed by significantly higher lactate concentrations in the first two postoperative hours (p < 0.001). Increased lactate concentrations during the first two postoperative hours were also a significant parameter for the occurrence of postoperative complications (p < 0.001). Patients with lethal courses already showed intraoperatively increased lactate values in comparison to those patients who could be transferred to a normal ward for further recovery (p < 0.05). From the statistical point of view, patients with lactate concentrations of more than 4.0 mmol/l lasting for more than two hours after an operation had bad prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)