Greater palatine canal injections reduce operative bleeding during endoscopic sinus surgery: a systematic review and meta-analysis

Objectives: The use of greater palatine canal (GPC) injections of a local anesthetic and a vasoconstrictor to decrease surgical bleeding during endoscopic sinus surgery (ESS) is controversial. We investigated the role of a preoperative GPC injection to minimize intraoperative bleeding during ESS in patients with chronic sinusitis through a meta-analysis of the relevant literature. Data sources: PubMed, SCOPUS, and the Cochrane database. Review methods: We screened the relevant literature published before May of 2018. Five articles that compared the pre-operative GPC injection (treatment group) with a placebo or no treatment (control group) were included for this analysis of the outcomes, which included an endoscopic grade of nasal bleeding and intraoperative hemodynamic stability during ESS. Results: The endoscopic grade in the treatment group was significantly reduced when compared with the control group. No significant adverse effects were reported in the enrolled studies. The subgroup analyses of these results compared the concentrations of adrenalin (1:80,000 or 1:100,000), and adrenalin 1:80,000 showed significant effects on intraoperative bleeding when compared to adrenalin 1:100,000. Conclusion: This study demonstrated that GPC injections of local anesthesia with 1:80,000 adrenaline for ESS effectively reduced intraoperative bleeding. Additionally, this procedure showed no significant adverse effects, such as hemodynamic instability. However, the standardized dosing needs further investigation and more trials. Level of evidence: Ia.