Contents lists available at ScienceDirect International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl The effects of ondansetron versus dexamethasone on electrocardiographic markers of ventricular repolarization in children undergoing cochlear implant Reza Safaeian a , Valiollah Hassani a , Alimohamad Asghari b , Masood Mohseni a,* , Haleh Ashraf c , Zahra Sadat Koleini a a Department of Anesthesiology, Iran University of Medical Sciences, Tehran, Iran b Skull Base Research Center, The Five Senses Health Research Institute, Iran University of Medical Sciences, Tehran, Iran c Cardiac Primary Prevention Research Center (CPPRC), Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran ARTICLE INFO Keywords: Arrhythmia QT interval Ondansetron Dexamethasone Cochlear implant Nausea ABSTRACT Introduction: Congenital hearing loss is associated with cardiac rhythm disturbances namely long Q-T syndrome. This study was designed to investigate the effect of anti-emetic doses of ondansetron and dexamethasone on ECG recordings in children undergoing cochlear implant surgery. Methods: Sixty-three pediatric patients scheduled for elective cochlear implantation were enrolled in the study. Two patients were excluded as their baseline ECG showed long QT syndrome. Anesthesia was induced with fentanyl, propofol and atracurium and maintained with propofol. Dexamethasone 0.1 mg.kg -1 or ondansetron 0.2 mg.kg -1 was randomly administered for the participants approximately 30 min before the end of surgery. ECG recording was performed 15 min after induction of anesthesia and 15 min after dexamethasone/ondan- setron administration. RR interval, QRS duration, QT interval, and Tp-e interval were measured by a blinded cardiologist. Results: Ondansetron resulted in no significant changes in RR, JTc and QTc intervals; while prolongedTp-e in- terval. Multivariable logistic regression analysis showed that use of ondansetron was an independent predictor of QTc prolongation after adjustment for age, gender and baseline QTc (OR = 17.94, CI 95% 1.97–168.70, p = 0.011). The incidence of postoperative retching/vomiting in ondansetron group was significantly lower than dexamethasone group. (3.2% vs. 26.7%, p = 0.011). Conclusion: The risk of arrhythmias with the use of ondansetron in otherwise healthy candidates of cochlear implant is very low. However, the drug may induce significant changes in ECG parameters. The clinical sig- nificance of these changes in patients with cardiac conduction abnormalities should be investigated in further studies. 1. Introduction Nowadays, many children are admitted for cochlear implant for early onset inherited hearing loss [1]. One common complication of the surgery is post-operative nausea and vomiting (PONV) due to manip- ulation of the inner ear [1–3]. Common groups of antiemetic dugs in- cluding dopamine receptor antagonists like droperidol, 5HT3R receptor antagonists like ondansetron and corticosteroids such as dex- amethasone may provoke the risk of QT prolongation [4,5]. Long QT interval is partly because of delayed repolarization of the ventricles that might lead to arrhythmias such as ventricular tachycardia and torsade de point [6]. The frequency of long QT syndrome (LQTS) in children among all patients with congenital deafness is thought to be less than 1 in 50,000. However, patients with congenital sensorineural hearing loss including Jervell and Lange-Nielsen syndrome are already at increased risk of sudden cardiac death, even being asymptomatic before [7]. This necessitates ECG screening and a safe plan of anesthesia considering the potential for arrhythmogenicity of medications. New electrical markers, including the interval between the peak and the end of the T wave (T p-e), stand out due to their ability to suggest the presence of refractory transmural dispersion, with potential appli- cation in the stratification of arrhythmogenic risk in different popula- tions [8–12]. The JT interval is more effective for ventricle repolar- ization as it has been described more specific for arrhythmia prognosis https://doi.org/10.1016/j.ijporl.2020.109896 Received 26 September 2019; Received in revised form 6 January 2020; Accepted 18 January 2020 * Corresponding author. E-mail address: Masood.mohseni@gmail.com (M. Mohseni). International Journal of Pediatric Otorhinolaryngology 132 (2020) 109896 Available online 22 January 2020 0165-5876/ © 2020 Elsevier B.V. All rights reserved. T brought to you by CORE View metadata, citation and similar papers at core.ac.uk provided by eprints Iran University of Medical Sciences