Influence of extradural and general anaesthesia on natural killer cell activity and lymphocyte subpopulations in patients undergoing hysterectomy.

The effect of hysterectomy was studied on natural killer (NK) cell activity, the distribution of lymphocyte subpopulations, and the endocrine stress response in 16 patients allocated to receive extradural analgesia S5-T4 (group I) or neuroleptanaesthesia (NLA) (group II). In group II a significant decrease in NK cell activity was found after operation for at least 3 days, while surgery during extradural analgesia did not induce significant changes. The impaired NK cell activity was accompanied by leucocytosis and lymphopenia affecting the T-lymphocytes (OKT3+ and OKT4+), the B-lymphocytes (B1+) and NK cells (Leu 11+). Compared with group II, extradural analgesia significantly reduced the cortisol and noradrenaline response to surgery, while the adrenaline response in both groups was abolished. The results suggest that the decrease in NK cell activity and alterations in lymphocyte subsets induced by surgery and general anaesthesia can be prevented to a certain degree by extradural analgesia.