The effects of intravenous anaesthetic agents on human neutrophil chemiluminescence

Abstract

Intact neutrophil function is essential for the defence against infection. Any alteration in neutrophil function, which decreases their ability tu phagocytose and kill bacteria, might contribute to mortality and morbidity. We investigated the effects of clinical concentrations of thiopentone, Alfathesin, methohexitone, morphine, lidocaine and diazepam on the microbicidal oxidative function of human neutrophils. The. oxidative activity was assessed utilizing the technique of chemiluminescence, which is a measure office radical generation. Thiopentone and Alfathesin produced a significant dose dependent depression in chemiluminescence. There was a 21 per cent reduction in activity with thiopentone 5 μg.ml-1, a concentration equivalent to the free plasma concentration achieved following an anaesthetizing dose of thiopentone. There was a 55 per cent reduction in chemiluminescence at an alphaxolone concentration of 1.25 μg.ml-1, a concentration equivalent to the free plasma level obtained after induction of Alfathesin anaesthesia. The effect of thiopenione and Alfathesin was reversed by cell washing. Methohexitone, morphine, diazepam, and lidocaine caused no significant reduction in chemiluminescence over the dose ranges studied. These observations indicate that thiopentone and Alfathesin con adversely affect leucocyte function in vitro and, therefore, may contribute to impaired host resist ance in the perioperative period and in the intensive care unit. © 1983 Canadian Anesthesiologists.