# Effect of Subhypnotic Dose of Propofol on Respiratory Adverse Events Following Postoperative Tonsillectomy/Adenotosillecomy: A Systematic Review and Meta-Analysis

## TL;DR

This study finds that a low dose of propofol reduces laryngospasm and other respiratory issues in children after tonsillectomy or adenotonsillectomy.

## Contribution

The study provides new evidence on the efficacy of subhypnotic propofol in reducing postoperative respiratory complications in pediatric patients.

## Key findings

- Propofol significantly reduced laryngospasm, cough, and agitation in children post-surgery.
- No significant differences were found for laryngeal occlusion, cyanosis, stridor, or surgery duration.
- Evidence for laryngospasm is conclusive, but other outcomes require further large-scale trials.

## Abstract

Background: Laryngospasm is defined as glottis closure due to reflex constriction of the laryngeal muscles. It is one of the most common complications following pediatric anesthesia that can lead to hypoxemia, bradycardia, or aspiration. Laryngospasm following tracheal extubation has different reasons: presence of secretions, foreign body in the airway, or pain at the site of surgery. Propofol is usually used as an induction or maintenance agent. However, its use with the subhypnotic dose (0.5 mg/kg) is increasing nowadays for reducing the incidence of laryngospasm. This systematic review and meta-analysis aim to assess the efficacy of subhypnotic propofol in reducing the incidence of laryngospasm and respiratory complications in children following tonsillectomy or adenotonsillectomy and before extubation. Methods: We systematically searched the following databases: PubMed, Cochrane Library, Scopus, and Web of Science. Studies were included if they used propofol with a low dose (0.5 mg/kg) following tonsillectomy and before extubation. Both Randomized Controlled Trials (RCTs) and cohort studies published up until 27 December 2025 were included. We used the R software for statistical analysis. We employed a random-effects model for the analysis. Continuous outcomes were analyzed as mean differences (MD) and dichotomous data as risk ratios (RR), with 95% confidence intervals (CI). Heterogeneity was assessed using I2 statistics. Results: Our review included four RCTs and one prospective cohort study with 593 participants. Our analysis showed that propofol was significantly associated with a low incidence of laryngospasm (RR = 0.25, 95% CI 0.13–0.49), cough (RR = 0.08, 95% CI 0.01–0.62), and agitation (RR = 0.15, 95% CI 0.03–0.72) compared with the control group. However, there were no significant differences regarding laryngeal occlusion (RR = 0.70, 95% CI 0.20–2.46), cyanosis (RR = 1.13, 95% CI 0.14–9.43), stridor (RR = 1.38, 95% CI 0.76–2.50), and the duration of surgery (MD = 1.81, 95% CI −0.74 to 4.36). Conclusions: Our findings state that propofol had a lower significant incidence of laryngospasm than the control. Trial sequential analysis for laryngospasm indicated that evidence is conclusive. However, regarding the other outcomes, the evidence is still inconclusive, which suggests the need for future large-scale RCTs with larger sample sizes to validate these findings.