Comparison of hemodynamic response to adrenaline infiltration in children undergoing cleft palate repair during general anesthesia with sevoflurane and isoflurane

BACKGROUND AND AIMS: Systemic absorption of adrenaline often used for infiltration during cleft palate surgery leads to adverse hemodynamic responses. These hemodynamic responses may be attenuated by the volatile anesthetics. This study aims to compare the hemodynamic responses to adrenaline infiltration during isoflurane (ISO) and sevoflurane (SEVO) anesthesia. MATERIAL AND METHODS: Sixty children aged between 9 months and 48 months, weighing between 8 kg and 20 kg, undergoing primary repair of cleft palate were randomly allocated into two groups: Group ISO - anesthesia maintained with ISO (2 minimum alveolar concentrations [MAC]) and nitrous oxide 50% and group SEVO - maintained on SEVO (2 MAC) and nitrous oxide 50%. Surgical site was infiltrated with 1 ml/kg of 1:200,000 solution of adrenaline with 0.5% lignocaine. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial blood pressure (MAP) were noted at the end of infiltration and every 1 min for 5 min following infiltration. The percentage change of hemodynamic responses from baseline, following infiltration were compared between the two groups. RESULTS: There was no significant change in HR from baseline, and the response was comparable between the agents at all times. The blood pressure (BP) increased from baseline in both the groups but the increase was greater in SEVO than ISO group at 2 and 3 min after infiltration. The maximum change in HR from baseline (group ISO median 10.9% [interquartile range (IQR) 4.5-23.0] vs. group SEVO 26.5% [11.9-44.6]) was comparable in both the groups (P = 0.169). The maximum change in SBP was significantly greater in group SEVO than group ISO (42.8% [IQR 20.0-60.9] vs. 26.0 [11.3-44.5], P = 0.04). The incidence of significant change (>20%) of SBP, DBP, and MAP from baseline was significantly greater in group SEVO after infiltration and 1 min and 2 min after infiltration. There were no arrhythmias in any of the groups. CONCLUSION: Isoflurane results in greater attenuation of rise in BP during adrenaline infiltration compared to SEVO at similar MAC.