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
PDF
Downloads: 0
Views: 7

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

Referencias

1. Afshari A. Clonidine in pediatric anesthesia: the new panacea or a drug still looking for an indication? Curr Opin Anaesthesiol. 2019;32:327−33.

2. Zalunardo MP, Zollinger A, Spahn DR, Seifert B, Pasch T. Preoperative clonidine attenuates stress response during emergence from anesthesia. J Clin Anesth. 2000;12:343−9.

3. Ritz T, Kullowatz A, Goldman MD, et al. Airway response to emotional stimuli in asthma: the role of the cholinergic pathway. J Appl Physiol (1985). 2010;108:1542−9.

4. Rosenkranz MA, Esnault S, Gresham L, et al. Role of amygdala in stress-induced upregulation of airway IL-1 signaling in asthma. Biol Psychol. 2022;167:108226.

5. Rosenkranz MA, Esnault S, Christian BT, et al. Mind-body interactions in the regulation of airway inflammation in asthma: a PET study of acute and chronic stress. Brain Behav Immun. 2016;58:18−30.

6. Groeben H, Mitzner W, Brown Robert H. Effects of the a2-Adrenoceptor Agonist Dexmedetomidine on Bronchoconstriction in Dogs. Anesthesiology. 2004;100:359−63.

7. Zhang S, Zhang R, Cai M, Zhang K, Zhang M, Zheng J. Intranasal dexmedetomidine premedication in children with recent upper respiratory tract infection undergoing interventional cardiac catheterisation: A randomised controlled trial. Eur J Anaesthesiol. 2020;37:85−90.

8. Shen F, Zhang Q, Xu Y, et al. Effect of Intranasal Dexmedetomidine or Midazolam for Premedication on the Occurrence of Respiratory Adverse Events in Children Undergoing Tonsillectomy and Adenoidectomy: A Randomized Clinical Trial. JAMA Netw Open. 2022;5:e2225473.

9. Oglesby FC, Scholefield BR, Cook TM, et al. Peri-operative cardiac arrest in children as reported to the 7th National Audit Project of the Royal College of Anaesthetists. Anaesthesia. 2024;79:512−23.

10. Kellner DB, Urman RD, Greenberg P, Brovman EY. Analysis of adverse outcomes in the post-anesthesia care unit based on anesthesia liability data. J Clin Anesth. 2018;50:48−56.

11. Habre W, Disma N, Virag K, et al. Incidence of severe critical events in paediatric anaesthesia (APRICOT): a prospective multicentre observational study in 261 hospitals in Europe. Lancet Respir Med. 2017;5:412−25.

12. von Ungern-Sternberg BS, Boda K, Chambers NA, et al. Risk assessment for respiratory complications in paediatric anaesthesia: a prospective cohort study. Lancet. 2010;376:773−83.

13. Regli A, von Ungern-Sternberg BS. Diagnosis and management of respiratory adverse events in the operating room. Curr Anesthesiol Rep. 2015;5:156−67.

14. Hii J TT, Sommerfield D, Sommerfield A, Matava CT. von UngernSternberg BS. Risk assessment and optimization strategies to reduce perioperative respiratory adverse events in pediatric anesthesia ‒ Part 1 patient and surgical factors. Paediatr Anaesth. 2022;32:8−18.

15. Sommerfield D, Sommerfield A, Evans D, et al. Impact of honey on post-tonsillectomy pain in children (BEE PAIN FREE Trial): a multicentre, double-blind, randomised controlled trial. Anaesthesia. 2025. https://doi.org/10.1111/anae.16682.

16. Ohn M, Maddison KJ, Nguyen J, et al. Performance Accuracy of Wrist-Worn Oximetry and Its Automated Output Parameters for Screening Obstructive Sleep Apnea in Children. J Sleep Med. 2023;20:102−10.

17. Ohn M, Sommerfield D, Nguyen J, et al. Predicting obstructive sleep apnoea and perioperative respiratory adverse events in children: role of upper airway collapsibility measurements. Br J Anaesth. 2023;131:1043−52.

18. Rubin DB, Thomas N. Matching using estimated propensity scores: relating theory to practice. Biometrics. 1996;52:249−64.

19. Brookhart MA, Schneeweiss S, Rothman KJ, Glynn RJ, Avorn J, Sturmer T. Variable selection for propensity score models. Am J Epidemiol. 2006;163:1149−56.

20. van Buuren S, Groothuis-Oudshoorn K. mice: multivariate imputation by chained equations in R. J Stat Softw. 2011;45:1−67.

21. Pishgar F, Greifer N, Leyrat C, Stuart EA. MatchThem: matching and weighting after multiple imputation. arXiv [Preprint].

2020. arXiv:2009.11772.

22. R Core Team. R: a language and environment for statistical computing. Vienna: R Foundation for Statistical Computing; 2014. Available from https://www.R-project.org/.23. Ramgolam A, Hall GL, Zhang G, Hegarty M, von Ungern-Sternberg BS. Deep or awake removal of laryngeal mask airway in children at risk of respiratory adverse events undergoing tonsillectomy: a randomised controlled trial. Br J Anaesth. 2018;120:571−80.

24. Katz SL, Monsour A, Barrowman N, et al. Predictors of postoperative respiratory complications in children undergoing adenotonsillectomy. J Clin Sleep Med. 2020;16:41−8.

25. Shen F, Zhang L, Wang X, et al. Effect of Intravenous, Inhalational, or Combined Anesthesia Maintenance on Postoperative Respiratory Adverse Events in Children Undergoing Adenotonsillectomy (AmPRAEC): A Multicenter Randomized Clinical Trial. Anesthesiology. 2025;143:1484−96.

26. Jain A, Bhanwra A, Sharma A, Kewlani A, Saroa R, Palta S. Supraglottic airway devices versus endotracheal tube in children undergoing adenotonsillectomy - A systematic review and meta-analysis. Indian J Anaesth. 2025;69:1294−303.

27. Mikami M, Zhang Y, Kim B, Worgall TS, Groeben H, Emala CW. Dexmedetomidine’s inhibitory effects on acetylcholine release from cholinergic nerves in guinea pig trachea: a mechanism that accounts for its clinical benefit during airway irritation. BMC Anesthesiol. 2017;17:52.

28. Nishina K, Mikawa K, Uesugi T, Obara H. Oral clonidine does not change ventilatory response to carbon dioxide in sevofluraneanesthetized children. Paediatr Anaesth. 2004;14:1001−4.

29. Zhang J, Yin J, Li Y, Zhang Y, Bai Y, Yang H. Effect of dexmedetomidine on preventing perioperative respiratory adverse events in children: A systematic review and meta‑analysis of randomized controlled trials. Exp Ther Med. 2023;25:286.

30. Templeton TW SD, Hii J, Sommerfield A, Matava T. von UngernSternberg B. Risk assessment and optimization strategies to reduce perioperative respiratory adverse events in Pediatric Anesthesia Part 2: Anesthesia-related risk and treatment options. Pediatric Anesthesia. 2021;32:11.

31. Stepanovic B, Regli A, Becke-Jakob K, von Ungern-Sternberg BS. Preoperative preparation of children with upper respiratory tract infection: a focussed narrative review. Br J Anaesth. 2024;133:1212−21.

32. Ohn M, Eastwood P, von Ungern-Sternberg BS. Preoperative identification of children at high risk of obstructive sleep apnea. Paediatr Anaesth. 2020;30:221−31.

Submitted date:
09/01/2026

Accepted date:
23/06/2026

6a8dd1d9a9539545e1429384 rba Articles
Links & Downloads
2352-2291 (Electrónico) 0104-0014 (Impreso)
Braz J Anesthesiol ©2026 Todos los derechos reservados sobre el contenido de este sitio web. Los artículos siguen sus propias licencias.

Braz J Anesthesiol

Share this page
Page Sections