BACKGROUND: Nasotracheal intubation is associated with a risk of epistaxis. Decongestion of the nasal mucosa reduces the risk of epistaxis, and different vasoconstrictors may be used. Cocaine has both decongestive and analgesic properties, but it also has side effects. In this systematic review, we aimed to evaluate if cocaine decreases the occurrence and severity of epistaxis when administered topically to the nasal mucosa before nasotracheal intubation. METHODS: We conducted a systematic review and meta-analysis following the PRISMA guidelines based on a predefined protocol. We included randomized clinical trials comparing nasal cocaine to active comparators or placebo for nasotracheal intubation. Two reviewers independently screened studies for eligibility and performed data extraction. Relative risk with 95% confidence intervals was calculated. Predefined primary outcome measures were the occurrence and severity of epistaxis. Secondary outcomes were pain, mechanical complications, and patient-centered side effects. The risk of bias was evaluated using the revised Cochrane Risk of Bias 2 tool for randomized trials, and certainty of evidence on outcome level was assessed according to GRADE. RESULTS: Six trials (n = 457) were included
one trial was judged as having a low risk of bias. All six trials provided information on the occurrence of epistaxis. The meta-analysis did not support a difference in the occurrence of epistaxis between cocaine and its comparators (fixed effect: relative risk 0.90 [95% confidence interval 0.75 to 1.09, I CONCLUSION: This systematic review with meta-analysis demonstrated that the quantity and certainty of evidence on cocaine used for nasotracheal intubation is low and that there is no firm evidence for the benefits and harms of cocaine compared to other vasoconstrictors and topical analgetics or placebo. Consequently, sufficiently powered randomized trials assessing patient-centered outcomes, including outcomes on side effects, should be conducted before firm conclusions on cocaine for nasotracheal intubation can be drawn. EDITORIAL COMMENT: Epistaxis can occur with nasotracheal intubation, and topical drug vasoconstrictor effects have been used to reduce this risk. This analysis shows that the evidence base supporting the use of cocaine for reducing the risk of epistaxis in nasotracheal intubation is uncertain.