IMMUNE FUNCTION IN PATIENTS UNDERGOING OPEN VS LAPAROSCOPIC CHOLECYSTECTOMY

Background: Abnormal release of inflammatory mediators following surgi cal injury is associated with immunological alteration, which may pred ispose to sepsis. Laparoscopic surgery is associated with reduced post operative complications, but mechanisms are unclear. We hypothesized t hat early recovery following laparoscopic surgery may relate to minima l impairment of immune function. Design: Analysis of the temporal immu ne responses in two similar groups of patients randomized to open (n=2 2) vs laparoscopic (n=22) cholecystectomy. Patients were matched for a ge, height, weight, and operation time. Immune parameters, including m onocyte superoxide anion (O-2(-)) and tumor necrosis factor release, n eutrophil O-2(-) levels and chemotaxis, total white blood cell counts, partial arterial oxygen pressure, and serum cortisol and C-reactive p rotein levels were assessed preoperatively and on postoperative days 1 and 3. Results: There were significant increases (P<.001) in monocyte release of O-2(-) and tumor necrosis factor, neutrophil release of O- 2(-) and chemotaxis, and white blood cell count in the open vs laparos copic cholecystectomy study groups, with a concommitant decrease in pa rtial arterial oxygen pressure. These findings correlated with signifi cantly higher postoperative septic complications in the open cholecyst ectomy group (P<.05). There were no significant differences in either plasma cortisol or C-reactive protein levels between groups. All measu rements were carried out in a blinded fashion. Conclusions: This study demonstrates that laparoscopic surgery appears to be associated with similar metabolic responses compared with open surgery, while immune p arameters vary greatly between groups. The beneficial effects of lapar oscopic surgery may relate, in part, to preservation of immune functio n in the postoperative period.