Comparison of isoflurane with propofol on respiratory cilia

We have investigated the effects of two techniques of clinical anaesthesia on human respiratory cilia by measuring cilia beat frequency of nasal tissue. In a randomized, controlled study, 13 patients undergoing either inhalation anaesthesia with isoflurane or total i.v. anaesthesia with propofol and alfentanil had nasal ciliated epithelial samples removed at the beginning and after 1 h of anaesthesia. Mean cilia beat frequency in the group anaesthetized with isoflurane changed significantly from 11.5 (95% confidence interval (CI) 10.7-12.2) Hz to 9.1 (8.1-10.1) Hz after anaesthesia whereas in the group anaesthetized with propofol and alfentanil there was a change from 11.5 (10.7-12.2) Hz to 11.0 (10.2-11.8) Hz (ns). The difference between the anaesthetic agents on cilia beat frequency was significant (MANOVA, P < 0.01). These data suggest that different anaesthetic agents may impair respiratory defence mechanisms to differing extents.