Immunosuppressive effects of anesthesia and surgery in the newborn: I short-term effects

We examined short-term effects of anesthesia and surgery on the lymphocyte response of neonates and older children to a range of mitogens using a whole blood mitogen stimulation assay. Following induction of anesthesia, both neonates and older children demonstrated significantly decreased lymphocyte transformation to phytohaemagglutinin (PHA; P less than 0.005) and Con A (P less than 0.025) compared with preanesthetic values. Immediately, postsurgery, older children recovered fully their responsiveness to both PHA and Con A, while there was significant depression in their responsiveness to PWM (P less than 0.005) and SPA (P less than 0.05). In contrast, neonatal responsiveness to all mitogens was significantly reduced (P less than 0.005) immediately after surgery compared to preoperative values. At 24-hour postsurgery, neonatal responsiveness to PHA had returned to preoperative levels but Con A, PWM, and SPA responses continued to decline (P less than 0.005). These results suggest that the newborn is particularly susceptible to the immunosuppressive effects of anesthesia and surgery.