Abstract

Fourteen neonates born with congenital malformations were investigated for lymphocyte function before and after surgery. Total leucocyte and absolute lymphocyte counts were unaltered after surgery. The mean percentage of T-lymphocytes observed either pre- or postoperatively was considerably lower than that reported in older children and adults. While there was an increase in the percentage of B-lymphocytes after operation in the infants, the absolute number of B-cells remained unchanges. The preoperative transformation response of lymphocytes to PHA (mean 12.9 +/- 5.4 X 10(3) counts/min) was little different from the postoperative values (mean 12.4 +/- 4.4 X 10(3) counts/min). These results suggest that the neonate is immunologically different from older children and adults in its response to anaesthesia and surgery.