The effects of anesthesia and surgery on count and function of neutrophils.

The effects of anesthesia and surgery on neutrophil count, chemotaxis and neutrophil alkaline phosphatase (NAP) score were investigated in 10 patients who had elective spine surgery. Plasma levels of adrenaline, noradrenaline and cortisol were measured and correlations between hormonal levels and neutrophil count and function were assessed. Neutrophil count started increasing after the initiation of surgery, reached the highest level at 3 hours after surgery, and decreased gradually toward preanesthetic level on 3rd postoperative day. The increase in band cell: segment cell ratio is prominent, whereas lymphocytes decreased significantly. Neutrophil chemotaxis and spontaneous migration were increased significantly from the end of operation to 1st postoperative day. NAP score, assumed to reflect the neutrophil phagocytic activity, lowered transiently during anesthesia, then increased 1.6 times more than preanesthetic level on 1st postoperative day. It was indicated that the increased cortisol release rather than adrenaline due to body response to surgical stress might induce neutrophilia, and that the elective spine surgery might not be deleterious to the neutrophil function.