Objective: To evaluate the postoperative changes in circulating interleukin-2 (IL-2) concentration according to the severity of the surgical injury and other postoperative variables that could influence IL-2 production.
Design: Prospective observational study.
Setting: University hospital, Italy.
Subjects: 43 patients about to undergo major operations (gastric and colo-rectal resection for cancer), intermediate operations (open cholecystectomy or mastectomy for cancer), and minor operations (hernia repair or breast lump); 24 healthy age and sex matched controls.
Main outcome measures: Postoperative changes in serum concentrations of IL-2 after different degrees of surgery on the 1st, 3rd and 8th postoperative days correlated with changes in in vivo cellular mediated immunity (skin tests), duration of operation, blood transfusion or postoperative H2-blockers and antiprostaglandins.
Results: There were no significant variations in IL-2 serum concentrations postoperatively on ANOVA, and when the data were normalised, there were no significant changes in the median postoperative values after minor and intermediate operations. There was a slight but not significant increase in IL-2 concentrations after major operations. Neither blood transfusion nor duration of operation correlated with postoperative changes in IL-2, while postoperative antiprostaglandins and H2-blockers seemed to provide slight but not significant protection against a reduction in IL-2 concentrations.
Conclusions: Circulating IL-2 does not necessarily correlate with reported in vitro postoperative production of IL-2 and therefore seems to be of little use in monitoring immunosuppression in surgical patients.