Comparison of the Hemodynamic Effects of the Induction Agents Ketamine, Etomidate and Sevoflurane Using the Model of Electrical Velocimetry Based Cardiac Output Monitoring in Pediatric Cardiac Surgical Patients

Objective: To compare the haemodynamic effects of the induction agents ketamine, etomidate and sevoflurane using the model of electrical velocimetry based cardiac output monitoring in paediatric cardiac surgical patients. Design: Prospective randomized study. Setting: Tertiary care hospital. Participants: 60 children < 2 years age undergoing cardiac surgery. Interventions: The patients were randomized into 3 equal groups to receive 1.5-2.5 mg/kg iv ketamine (group K), 0.2-0.3 mg/kg iv etomidate (group E) or upto 8% sevoflurane (group S) as the induction agent. Hemodynamic parameters were noted before and after induction of anaesthesia utilizing a noninvasive cardiac monitor based on the model of electrical velocimetry. Measurements and Main Results: The demographic characteristics of the patients were similar in the three groups. The HR decreased in all groups, least in group E (P ≤ 0.01) but the MAP decreased only in group S (P ≤ 0.001). In group S, the stroke volume improved from 9 ± 3.2 ml to 10 ± 3.2 ml (P ≤ 0.05) and the stroke volume variation decreased from 25% ± 6.4% to 13% ± 6.2% (P ≤ 0.001). The stroke index and systemic arterial saturation improved in all groups (P ≤ 0.01). The cardiac index and index of contractility were unchanged. The transthoracic fluid content reduced in groups E and S, but did not change in group K (P ≤ 0.05). Conclusions: Etomidate appeared to provide the most stable conditions for induction of anesthesia in children undergoing cardiac surgery, followed by ketamine and sevoflurane.