26 September 2023

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Cannabis users require more anesthetic agents for general anesthesia

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Background

The use of cannabis in the general population has steadily increased over recent years and there is limited literature regarding the anesthetic implications of chronic cannabis use, particularly in the setting of outpatient anesthesia.

Purpose

To determine whether chronic cannabis users undergoing deep sedation or general anesthesia during ambulatory procedures require more anesthetic agents than non-users.

Study design, setting and sample

A retrospective cohort study of subjects undergoing deep sedation or general anesthesia at the Oklahoma University Oral and Maxillofacial Surgery (OMS) Clinic from January to December 2022 was performed. The inclusion criteria were duration of anesthetic procedure between 15-40 minutes; use of propofol, fentanyl, ketamine, and midazolam; extraction of at least 2 teeth. The exclusion criterion was patients undergoing adjunctive procedures other than extractions during sedation.

Predictor variable

Cannabis use status grouped as users and non-users. A user was defined as a subject who self-reported any regular use of cannabis.

Outcome variable

The primary outcome variable was the amount of intravenous anesthetic agents administered. Secondary outcome variables included the length of the procedure and the number of teeth extracted.

Covariates

Age, sex, and the senior-most resident involved in the sedation.

Analyses

IBM SPSS was utilized to perform descriptive statistics, paired T-tests, ANOVA, and multivariate linear regression. A level of significance of 5% (p < 0.05) was used for all analyses.

Results

Four hundred and ninety-nine subjects were identified, 189 met the inclusion criteria, and 57 reported using cannabis. The mean age of non-users was 28.2 ± 7.8 years and that of users was 26.6 ± 6.4 years (p = 0.09). Females represented 71.9% of non-users and 72.7% of users. Cannabis users received significantly more propofol (117.5mg ± 71.3 vs. 152.5mg ± 101.8; p = .004), midazolam (4.7mg ± 1.0 vs. 5.1mg ± 1.5; p = 0.01), ketamine (40.2mg ± 15.7 vs. 46.1mg ± 16.9; p = 0.01), and fentanyl (75.2μg ± 26.3 vs. 88.6μg ± 32.8; p = 0.002) than non-users, despite extracting a similar number of teeth (4.5 ± 3.1 vs. 4.4 ± 3.5; p = 0.37) in a similar amount of time (25.5 ± 7.3 vs. 27.3 ± 7.8; p = 0.06).

Conclusion and relevance

Cannabis users required more propofol, midazolam, ketamine, and fentanyl than non-cannabis users during outpatient OMS procedures.

Daniel Ripperger et al. "Cannabis Users Require More Anesthetic Agents for General Anesthesia in Ambulatory OMS Procedures." Journal of Oral and Maxillofacial Surgery. 13 September 2023. DOI: https://doi.org/10.1016/j.joms.2023.09.008.