The influence of several intravenous anaesthetics on the chemotaxis of human monocytes in vitro.

Monocytes play a very important part in humoral as well as in cell-mediated immunity. At present, however, the knowledge of the influence of anaesthetic agents on the functions of monocytes is limited. In the present study, the effects of thiopentone, methohexitone, ketamine, midazolam, droperidol, propofol, etomidate, and fentanyl on monocyte chemotaxis were examined in vitro using a 48-well microchemotaxis chamber. Clinically relevant concentrations of ketamine, midazolam, and droperidol significantly (P < or = 0.05) inhibited chemotaxis. For that reason, it is possible that these anaesthetics impair the immunological system in vivo. This possibility should be further examined.