Impaired B lymphocyte function during open-heart surgery. Effects of anaesthesia and surgery.

B lymphocyte function in vitro was measured in patients undergoing open-heart surgery. Conventional balanced anaesthesia, or high-dose fentanyl anaesthesia was used. Pokeweed mitogen (PWM) induced lymphocyte transformation was depressed at the end of the operation, but the response to formalinized Staphylococcus aureus Cowan I (StaCw) was not. The numbers of immunoglobulin producing and secreting cells measured by an indirect protein A plaque-forming cell assay decreased after PWM-stimulation, but remained unchanged after StaCw stimulation at the end of the operation. IgG, IgM and IgA secretion by PWM- and StaCw-stimulated lymphocytes, into the culture medium, was depressed in the period after operation. Depressed immune functions occurred after open-heart surgery, but not in association with anaesthesia alone before surgery. The decreases were not mediated by hydrocortisone-sensitive suppressor cells. Minor differences between the two anaesthetic techniques were found in lymphocyte proliferative responses.