Median effective dose of intranasal dexmedetomidine sedation for transthoracic echocardiography in pediatric patients with noncyanotic congenital heart disease: An up-and-down sequential allocation trial.

Abstract

Intranasal dexmedetomidine can provide adequate sedation during short procedures. However, previous literature investigating the single-dose use of intranasal dexmedetomidine for sedation during transthoracic echocardiography in younger children is scarce, and the effects of age on sedation with intranasal dexmedetomidine remain controversial. This study was to determine the 50% effective dose and estimate the 95% effective dose of single-dose intranasal dexmedetomidine to induce sedation in pediatric patients with noncyanotic congenital heart disease, and also determine the effect of age on the dose required for sedation. Patients were stratified into three age groups of 1-6months, 7-12months, and 13-36months. Intranasal dexmedetomidine started at a dose of 2μgkg-1 on the first patient. The dose of dexmedetomidine for each subsequent patient was determined by the previous patient's response using Dixon's up-and-down method with an interval of 0.25μgkg-1 . Sedation scale and recovery were assessed by the Modified Observer Assessment of Alertness and Sedation Scale and Modified Aldrete Recovery Score. The 50% effective dose was determined by Dixon's up-and-down method. In addition, both 50% effective dose and 95% effective dose were obtained using a probit regression approach. Other variables included sedation onset time, echocardiography time, wake-up time, discharge time, heart rate, blood pressure, oxygen saturation, respiratory rate, and adverse events such as vomiting, regurgitation, and apnea. The study population was comprised of 70 patients. The 50% effective dose (95% confidence interval) and the 95% effective dose (95% confidence interval) of intranasal dexmedetomidine for sedation were 1.8 (1.58-2.00) μgkg-1 and 2.2 (1.92-5.62) μgkg-1 in patients aged 1-6months, 1.8 (1.61-1.95) μgkg-1 and 2.1 (1.90-2.85) μgkg-1 in patients aged 7-12months, 2.2 (1.92-2.37) μgkg-1 and 2.7 (2.34-6.88) μgkg-1 in patients aged 13-36months, respectively. The 50% effective dose in age group 13-36months was higher than those of age group 1-6months (P=.042) and 7-12months (P=.043). There were no differences in sedation onset time, echocardiography time, wake-up time, and discharge time between groups. None of the patients experienced oxyhemoglobin desaturation, hypotension, or bradycardia during the procedure. No significant adverse events occurred. Single-dose of intranasal dexmedetomidine was an effective agent for patients under the age of 3years requiring sedation for transthoracic echocardiography. The 50% effective dose of intranasal dexmedetomidine for transthoracic echocardiography sedation in children aged 13-36months was higher than in children <13months.