Background and objective: Previous studies have shown that general anaesthetic agents modulate the production of hypothalamic prostaglandins (PG) D2 and E2, which are mediators of sleep and wakefulness respectively. Although flurbiprofen, a cyclo-oxygenase inhibitor, is used clinically as a non-steroidal anti-inflammatory agent and postoperative analgesic, it reduces prostaglandin production. Thus, this agent may affect the depth of sedation during general anaesthesia. In this study, we examined if flurbiprofen affects the bispectral index, which correlates with sedation levels.

Methods: Fifteen patients who underwent elective surgery under total intravenous anaesthesia with propofol and fentanyl were studied. The sedation level was monitored using a bispectral index monitor. On attainment of stable haemodynamics and a bispectral index, patients were given flurbiprofen axetil 50 mg intravenously. A bispectral index and 95% spectral edge frequency were recorded before and 5, 10, 15, 20 and 30 min after flurbiprofen axetil intravenously.

Results: Bispectral indexes of 51.7 (95% CI: 47.3–56.8), 51.7 (47.1–56.3), 51.3 (46.3–56.3), 50.3 (45.8–54.2), 48.9 (43.6–54.1) and 50.3 (45.5–55.2) at 0, 5, 10, 15, 20, 30 min after flurbiprofen axetil intravenously were observed. There was no change in this or 95% spectral edge frequency.

Conclusions: Clinical dose of flurbiprofen axetil does not alter the bispectral index and 95% spectral edge frequency under total intravenous anaesthesia with propofol and fentanyl.