Comparison of Bolus and Infusion of Esmolol on Hemodynamic and Parathormone Responses to Tracheal Intubation

Abstract

Background: We compared the effects of esmolol bolus and bolus+infusion on the haemodynamic and serum parathormone (PTH) level changes related to laryngoscopy and tracheal intubation (LTI).
Material and Methods: A total of 60 patients were enrolled to the study. The patients were randomly divided into 3 equal groups: esmolol 1.5 mg/kg as a bolus within 20 seconds (Group B), a loading dose of 0.5 mg/kg of esmolol within 20 seconds followed by esmolol was infused at a rate of 100 µg/kg/min for ten minutes (Group I) and isotonic saline (Group P). Induction of anesthesia was performed with thiopentone and rocuronium. Mean arterial pressure (MAP) and HR were recorded baseline (T0), before laryngoscopy (T1) and 1, 3, and 5 minutes after intubation (T2, T3 and T4 respectively). PTH and calcium were measured baseline, 5min and 1h after the intubation.
Results: There were significant decreases in HR at T1 (77±13 beat/min) compared to T0 (84±13 beat/min) in group I. There were significant increases in HR at T2, T3, and T4 (p<0.001) in group I and group P compared to T0. MAP increased significantly in all groups at T2 compared to baseline. We observed significant increases in PTH and decreases in calcium after the intubation in all groups.
Conclusion: Both dosing regimens of esmolol two minutes before laryngoscopy are insufficient in preventing
pressor and hormonal responses related to LTI.