The Effects of Continuous Epidural Anesthesia and Analgesia on Stress Response and Immune Function in Patients Undergoing Radical Esophagectomy

We investigated whether perioperative extensive epidural block (C3-L) affects postoperative immune response in patients undergoing radical esophagectomy. Patients undergoing radical esophagectomy were randomly assigned to either general anesthesia with continuous epidural infusion via 2 epidural catheters that was continued for postoperative analgesia (group E, n = 15) or intraoperative general anesthesia and postoperative IV morphine analgesia (group G, n = 15). Plasma levels of stress hormones, cytokines, C-reactive protein (CRP), leukocyte counts, and distribution of lymphocyte subsets were assessed before and after surgery and on postoperative days (PODs) 1 and 3. In comparison with group E, significant increases in plasma epinephrine level at the end of surgery (P0.05) and norepinephrine level at the end of surgery (P0.01) and on POD1 (P0.01) and POD3 (P0.01) and significant decrease in cluster of differentiation (CD4/CD8 ratio) at the end of surgery (P0.05) were observed in group G. However, there were no significant differences in other variables between groups. In both groups, plasma cortisol, adrenocorticotropic hormone, interleukin (IL)-1beta, IL-6, IL-10, and CRP levels were increased after surgery (each group P0.01) and IL-1beta, IL-6, IL-10, and CRP were still increased on POD1 and POD3 (each change, each group P0.01). Leukocyte counts were increased on POD1 (each group P0.05) and POD3 (each group P0.01). The proportion of lymphocytes decreased from the end of surgery to POD3 (each group P0.01). The proportion of B cells was increased on POD1 (each group P0.01); that of natural killer cells was decreased at POD1 and POD3 (each group P0.01). We conclude that tissue damage and inflammation apparently overcome the effects of extensive epidural block on stress response and immune function in radical esophagectomy.