INCREASE OF INTERLEUKIN-6 PLASMA-CONCENTRATIONS AND HLA-DR POSITIVE T-LYMPHOCYTES AFTER HYPOTENSIVE ANESTHESIA WITH SODIUM-NITROPRUSSIDE

Interleukin-6 (IL-6), a cytokine involved in the pathogenesis of sepsi s sepsis and septic shock, and lymphocyte subpopulations were measured in blood circulation of patients receiving sodium nitroprusside (SNP) for induction of hypotension. The aim of this study was to evaluate w hether this procedure influences distribution of lymphocyte subsets an d IL-6 response. 30 patients of ASA physical status I and II scheduled for nose-septum correction were randomly assigned to the SNP- or cont rol group (without SNP). Patients were anaesthetized with fentanyl, et omidate and isoflurane in 66% nitrous oxide. SNP was administered cont inuously during 60 min and mean arterial blood pressure was reduced to 50 mmHg. Before and after induction of anaesthesia, 60 min after the beginning of the operation (end of SNP-infusion) and on the first post operative day, IL-6 plasma concentrations were determined by ELISA. Th e percentages of B-, T-lymphocytes, T-helper, T-suppressor cells and H LA-DR positive (activated) T-lymphocytes were examined by direct immun ofluorescence using monoclonal antibodies. On the first day after surg ery IL-6 plasma concentrations were significantly elevated in the SNP- group compared to preoperative values. In this group the Values were h igher than in control patients [30.5 (10.9-47.5) pg/ml vs. 17.4(8.5-21 .5) pg/ml]. The percentage of HLA-DR positive T-cells was 25.8+/-4.9% in the patients with SNP on the first postoperative day; it was signif icantly higher than in control patients [16.5+/-3.7%]. We conclude tha t SNP-administradon increases percentage of activated T-cells and IL-6 secretion.