Prospective Observational Cohort Study on Dexmedetomidine and Midazolam in Mechanically Ventilated Children

Abstract

Introduction: Though target sedation was achieved with Midazolam and Dexmedetomidine, Dexmedetomidine has demonstrated the lesser complications and shorter duration of stay in Intensive Care Unit (ICU). Most of the studies are reported from high income countries. The studies on Midazolam and Dexmedetomidine use in mechanically ventilated children are scanty in low-middle income regions. Aim: To compare the efficacy of Midazolam and Dexmedetomidine for sedation in mechanically ventilated children. Materials and Methods: This prospective observational cohort study was conducted in academic hospital Paediatric Intensive Care Unit (PICU) from March 2015 to June 2016. Children aged less than 13 years mechanically ventilated for more than 24-hour and received sedative with either infusion of Midazolam or Dexmedetomidine without loading dose were involved. Patients with unstable haemodynamic throughout PICU stay and expired within 24-hour and incomplete medical data were excluded. Intermittent Fentanyl/Morphine was used as when needed as per treating team decisions. Sedation assessment was performed with Ramsey sedation scale (RSS, target=3-4 out of 6), Tracheal suctioning score and PICU sedation score. The primary outcome was “percentage of time with target sedation” till extubation. The secondary outcome was the cumulative dose of sedation used, the need for rescue sedation and the rate of complications, organ dysfunction {by Sequential Organ Failure Assessment (SOFA) score and Paediatric Logistic Organ Dysfunction (PELOD) score} and the length of stay in ventilation, PICU and mortality. Results: A total of 115 patients (Midazolam-group, n=63 and Dexmedetomidine-group, n=52) were enrolled. The median age was 12 months (IQR 8-30). Mean (±SD) PRISM-III score was 11.3±7.2. About 54.8% were ventilated for respiratory pathology, followed by CNS pathology (25.2%) and sepsis (10.4%). Mean (±SD) percentage of the duration of proper sedation was not significantly different in Midazolam-group (83.4±15.6) and Dexmedetomidine-group (81.4±17) (p=0.510). The cumulative dose (microgram per kg) requirement was higher in Midazolam-group {median (IQR) 12.2 (9.8-17.1) vs. 9.6 (5-15.3); p=0.019)}.No difference was note in need for “rescue dose of sedation” per patient {median (IQR) 1 (0-2) vs. 1 (0-2)}, rate of complications (bradycardia 9.5% vs. 1.9%; hypotension 9.5% vs. 5.8%). No difference was noted in organ dysfunction score {mean difference, 95% CI; SOFA score: -0.2 (-1.6 to 1.33); p=0.808 and PeLOD score: 1.3 (-1.5 to 4.1); p=0.364}, duration of ventilation (median, IQR 2.7 (2-3.3) vs. 2.0 (1.5-3.1) days and mortality (20.6% vs. 21.2%). PICU stay was significantly lower in Midazolam-group (median, IQR 3 days, 1-5 vs. 5 days, 4-6; p=<0.001). Conclusion:Midazolam and Dexmedetomidine were associated with similar target sedation with a comparable rate of complications in mechanically ventilated children. However, Midazolam required a higher cumulative dose to achieve target sedation.