In vitro toxicity of halogenated anaesthetics on guineapig alveolar macrophages, surviving in gas phase.

The potential toxicity of halogenated anaesthetics on cellular immunity has been investigated on guineapig macrophages in gas phase by measuring the adenosine 5' triphosphate (ATP) concentration in the macrophages. A toxicity index (TI) was obtained by comparing the ATP concentration in vapour or gas-exposed macrophages with that of control cells. The TI for 5% halothane in air after 24 h was 31.2 +/- 8.3%. The TI for 5% enflurane in air was 12.7 +/- 6.6% (P less than 0.01). In an oxygen-enriched gas mixture (60%), the halothane TI increased to 65 +/- 6.6%, whereas that for enflurane remained at 15.4 +/- 16.9% (P less than 0.01). In macrophages exposed to 1% halothane, or 2% enflurane, in 50% nitrous oxide in oxygen, for 3 and 6 h, the halothane TI (0.4 +/- 3.3%) and the enflurane TI (2.5 +/- 4.1%) did not differ significant from the control group after 3 h. However, after 6 h exposure the halothane TI (31.3 +/- 9.6%) and the enflurane TI (17 +/- 20%) were different (P = 0.05) from control. It is concluded that the prolonged administration of high concentrations of halothane and enflurane alone decreased macrophages ATP concentration. A high concentration of oxygen in the gas mixture increased significantly the halothane TI.