Brazilian Journal of Anesthesiology
https://app.periodikos.com.br/journal/rba/article/doi/10.1016/j.bjane.2026.844792
Brazilian Journal of Anesthesiology
Original Investigation

Impact of perioperative clonidine on postoperative respiratory adverse events in children: a post-hoc observational analysis of prospectively collected datasets

David Sommerfield, Bojana Stepanovic, Daisy Evans, Andy Jeon, Anne Louise de Barros Garioud, Aine Sommerfield, Neil Hauser, R. Nazim Khan, Britta S. von Ungern-Sternberg

http://dx.doi.org/10.1016/j.bjane.2026.844792 Braz J Anesthesiol, Ahead of Print, 2026
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Abstract

Background

Clonidine, an alpha-2-agonist, has several applications in pediatric anesthesia. Sympathetic nervous system-mediated pathways contribute to airway reactivity, suggesting that clonidine could mitigate respiratory adverse events similarly to more selective agents.

Methods

This was a post-hoc analysis of prospectively collected observational datasets from three research projects on children (1‒16 years) undergoing elective extracapsular (adeno-) tonsillectomies between January 2018 and November 2021. Patients’ study data sheets and medical records were reviewed for clonidine use. The primary outcome was postoperative respiratory events (at emergence from anesthesia or in the post-anesthesia care unit). Post-anesthesia care unit length of stay was also monitored.

Results

The cohort consisted of 512 patients. The tonsillectomies were performed using coblation or electrocautery, local anesthetic infiltration; the airway was managed with a flexible supraglottic airway (97%). In the unadjusted cohort, postoperative respiratory events occurred in 44/306 children receiving clonidine (14%) and 50/203 children not receiving clonidine (25%) (OR = 0.616; 95% CI 0.361–1.047; p = 0.074). After propensity score matching, the between-group difference narrowed to 5 percentage points in the complete-case dataset and 4 percentage points in the multiply imputed dataset, with no statistically significant association between clonidine and postoperative respiratory events. Clinically, clonidine use did not prolong stay in PACU, 48.2 minutes (±22.5), compared with 50.0 minutes (±23.5).

Conclusions

This post-hoc analysis found no statistical reduction in postoperative respiratory events associated with perioperative clonidine in pediatric patients following extracapsular (adeno)tonsillectomy and a flexible supraglottic airway. Clonidine use did not prolong time in PACU.

Keywords

Clonidine; Patient Outcome Assessment; Pediatric Anesthesia; Perioperative Period; Postoperative Complications; Signs and Symptoms, Respiratory

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Submitted date:
01/09/2026

Accepted date:
06/23/2026

6a8dd1d9a9539545e1429384 rba Articles
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