Comparative effects of volatile anaesthetic agents and nitrous oxide on human leucocyte chemotaxis in vitro

Infection following surgery is not uncommon. Human leucocytes play a vital role in the body's defense against infection. In order to decrease perioperative morbidity and mortality from infection, it is important to define the comparative effects of different anaesthetic agents on the leucocyte function. Therefore, the effect of equipotent concentrations (MAC 1) of isoflurane, enflurane, halothane, methoxyflurane and 70 per cent nitrous oxide, on the leucocyte chemotactic migration was investigated in vitro. The chemotactic migration of neutrophils and monocytes, with and without equilibration with MAC 1 concentrations of different volatile anaesthetics and 70 per cent nitrous oxide, was compared by using a modification of Boyden's method. Chemotactic migration of both cell types was unaffected by isoflurane, but a significant depression of chemotactic migration was observed with enflurane, halothane, methoxyflurane and nitrous oxide (p less than 0.05). The severity of depression of migration was maximal with nitrous oxide, followed by methoxyflurane, halothane and enflurane in order. It is concluded that equipotent concentrations of various anaesthetic agents produce different degrees of depression of leucocyte chemotactic migration in vitro.