RESUMO
BACKGROUND: Using the reverse Trendelenburg position (RTP) during functional endoscopic sinus surgery (FESS) is a safe, simple, and cost-free method that has been found to reduce intraoperative blood loss. However, the critical angle of RTP that produces the least amount of bleeding without compromising surgical technique and safety remains unanswered. The objective of this study was to assess the effects of 5-degree, 10-degree, and 20-degree RTP (5-RTP, 10-RTP, and 20-RTP, respectively) on intraoperative bleeding during FESS. METHODS: This double-blind randomized controlled trial involved 75 patients with chronic rhinosinusitis (CRS) with and without nasal polyposis undergoing FESS. Twenty-five patients were enrolled into each group: 5-RTP, 10-RTP, and 20-RTP. Boezaart endoscopic field-of-view score (BS), total blood loss (TBL), mean arterial blood pressure (MABP), operating time, and blood loss per minute were recorded. An intention-to-treat analysis was used, with a Bonferroni adjustment for multiple comparisons. RESULTS: Intervention groups were comparable in age, sex, nasal polyposis, and disease severity. Mean values of BS and TBL were as follows: 5-RTP (2.0, 231 mL), 10-RTP (1.8, 230 mL), and 20-RTP (1.4, 135 mL). The differences in means were significant for BS (p < 0.01) and TBL (p = 0.03). There was no significant difference in MABP (p = 0.85), operating time (p = 0.10), or blood loss per minute (p = 0.11) between the 3 groups. Pairwise comparison between 5-RTP vs 20-RTP found significant difference in BS (p < 0.01) but not TBL (p = 0.04). Significance was not found in similar comparisons of 10-RTP vs 20-RTP and 5-RTP vs 10-RTP (p > 0.03). CONCLUSION: FESS in 20-RTP produced the best BS and lowest blood loss without compromising surgical technique.