Correlation between acid-base status, concentrations of lactate and of pyruvate in blood and cerebrospinal fluid in patients treated in an intensive care unit.

Results of examinations of 41 patients treated in an intensive care unit are reported. The patients were divided into three groups and examined on the first and twelfth days of treatment. In the first group were 15 patients who had received circulatory resuscitation, the second group was 13 patients with lesions of the central nervous system of traumatic or vascular origin and the third group was 13 patients with acute respiratory insufficiency of toxic or infective origin. The cerebrospinal fluid of patients in the second group showed the lowest pH (mean pH 7.28) and bicarbonate concentration (19.05 mequiv./1); this group also had the lowest PO2 values. Moderate respiratory alkalosis was observed in the arterial blood of patients with lesions of the central nervous system. Concentrations of lactate in the cerebrospinal fluid were increased in all three groups of patients although blood lactate concentrations were normal. The lactate/pyruvate concentration ratio was highest in the resuscitated patients.