Impaired metabolic activity of phagocytic cells after anaesthesia and surgery.

Peripheral blood leucocytes and their phagocytosis-associated metabolic activity were studied in 65 patients after elective surgery representing similar degrees of surgical trauma. Halothane (group A) or neurolept (group B) anaesthesia were given to 50 patients. Fifteen patients had extradural blockade only (group C). Leucocytosis was observed immediately after surgery in group B: patients in groups A and C responded more slowly. The higher 2nd-day values were followed by a decrease in leucocyte numbers on the 5th day. Although patients in groups A and B showed immediate decreases in nitroblue tetrazolium reduction, recovery was noted only in group B on the 5th day after operation. It is postulated that leucocytes with damaged membranes and receptors are probably lacking in the necessary functional integrity to fight invading microorganisms.