Immune response following surgical trauma.

In this brief review a description of changes in specific immune response with regard to surgical trauma is presented. The effect of anesthesia on these responses appears to be minimal. The mechanisms underlying functional abnormalities include serum inhibitory factors, suppressor monocytes, deficiency of lymphocyte-monocyte-associated fibronectin, and deficiency of IL-2 production. The factor of stress should be taken into consideration when interpreting the effect of surgery, because stress is known to influence various immune responses. The reason for various discrepancies among investigators appear to be due to technical differences, type of surgery, duration of surgery, temperature at which surgery was done (both hypothermia and hyperthermia modify the immune response), blood or plasma infusion (they appear to activate T-cells in vivo), underlying disease, and baseline immunologic status (for example, patients with malignancy with depressed preoperative immunologic status might be more or less susceptible to the effects of surgical trauma), nutritional status, drugs used, etc. Quantitative analysis should be done using monoclonal antibodies and FACS. In none of the studies published was FACS used. More detailed studies are required to understand non-T- and non-B-cell and macrophage functions in patients undergoing surgical trauma. Specific antibody responses should be studied to explain the high frequency of sepsis in the postoperative period.