Deliberate hypotension with propofol under anaesthesia for functional endoscopic sinus surgery (FESS)

Abstract

Background: Functional endoscopic sinus surgery (FESS) is a minimally invasive technique that is used to treat chronic sinusitis. Small bleeding areas can reduce operative visibility and result in destruction of surrounding structures. Deliberate hypotension (lowering the mean arterial blood pressure to between 50 and 65 mm Hg in normotensive patients) using a range of pharmacological agents during general anaesthesia reduces blood loss in many operations. Objectives: We aimed to compare the use of the intravenous anaesthetic agent propofol versus other techniques for deliberate hypotension during FESS with regard to blood loss and operative conditions. Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 1), MEDLINE (1950 to April 2012), EMBASE (1980 to April 2012), LILACS (1982 to April 2012) and ISI Web of Science (1946 to April 2012). We also searched the reference lists of relevant articles and conference proceedings and contacted the authors of included trials. Selection criteria: We sought all randomized controlled trials (RCTs) conducted to compare propofol with other techniques. Our primary outcome was total blood loss (TBL). Other outcomes included surgical field quality, operation time, mortality within 24 hour, complications and failure to reach target blood pressure. Data collection and analysis: Two review authors independently extracted details of trial methodology and outcome data from reports of all trials considered eligible for inclusion. All analyses were made on an intention-to-treat basis where possible. When I2 was < 40% and the P value from the Chi2 test was > 0.10, we pooled data by using the fixed-effect model. Otherwise we pooled data by using the random-effects model. Main results: We included four studies with 278 participants in the review. Deliberate hypotension with propofol did not decrease TBL (millilitres) when compared with inhalation anaesthetics in either children or adults. Propofol improved the quality of the surgical field by less than one category on a scale from 0 (no bleeding) to 5 (severe bleeding) (mean difference (MD) 0.64 better with propofol, 95% confidence interval (CI) 0.37 to 0.91 better), but no difference in operation time was reported. Failure to lower blood pressure to target was less common in the propofol group (relative risk of failure with propofol (RR) 0.24, 95% CI 0.09 to 0.66). Authors' conclusions: Using propofol to achieve deliberate hypotension may improve the surgical field, but the effect is small. Deliberate hypotension with propofol did not decrease TBL and operation time. RCTs with good quality methodology and large sample size are required to investigate the effectiveness of deliberate hypotension with propofol for FESS.