Cimetidine On The Cellular Immune Function In Open Heart Surgery Regulatory Role

Objective: To sttldy tl1e damaging effects of cardiopulmonarybypass(CPB) on hllman cellu1ar immune ftlnction and the immunemodulating effect ofcilnetidine.Methods: ln a prospective randomized study,20 patients weredivided into two 8iroups of equal size. Cimetidine g'roup patientsreceived 0.4g of cimetidine intravenously before bypass and 0.2g q6hintravenous inftlsion of cimetidine after the operation, continuing unti1lthe fift1l postoperative day. Control-8iroup patients receivedconvel1tional perioperative theraPy. Lymphocyte subsets, lymphocytetransformation index were measured perioperatively.Results: Postoperative reduction in the percentages of CD',.CD+#cells were observed to some deg'ree in both groups. Incimetidine grotlp,tl1ese values decressed slowly and restored qtlickly,significant reduction in CD+,was observed on postoperative days l to3.In contrast,CD+,counts were elevated significa11tly on tl1epostoperative days l in control-Liroup. Postoperative reduction in tl1elevel of CPM. PHA-SI al1d CD'./CD+,were obselved in control-gro[lp,llevertlleless,in cimetidine-group,these values restoredapproximately on the postoperative days 3.Conclusion: Cell-lnediated immunity is impaired after cardicoperations involving CPB, cimetidine can counteracts this depressiveef1bcts and may possibly reduce postoperative susceptibility toinfection.