Effect of Esmolol, Labetalol and Metoprolol for Attenuating the Cardiovascular Stress Response to Laryngoscopy and Intubation: A Comparative Study
Attenuating the Cardiovascular Stress Response to Laryngoscopy and Intubation
Background: To compare esmolol, labetalol and metoprolol in attenuating the cardiovascular response of L&I. Subjects and Methods: It was a randomized prospective study in 120 patients of 18-60 years, of ASA grade I and II, of either sex, posted for elective surgery under GA. After approval from ethical committee and informed written consent, the patients were randomly allocated in four groups of 30 each. Group C (control) received 10 ml 0.9% saline, group E esmolol 0.5 mg/kg (both 2min prior to induction), Group L labetalol 0.25 mg/kg and Group M metoprolol 0.1 mg/kg (both 5min prior to induction). All patients were pre-medicated with inj. ondansetron 0.1 mg/kg, inj. glycopyrrolate 0.004 mg/kg, inj. pen-tazocine 0.6 mg/kg and inj. midazolam 1 mg.All patients were induced with inj. thiopentone 5 mg/kg and succinylcholine 2 mg/kg. Anaesthesia was maintained on isoflurane, O2:N2O and Atracurium. Heart rate and BP were recorded: pre-operative, after pre-medication, after induction, after L&I, after 1, 3, 5, 10, 15 minutes following L&I. Results: All the study drugs significantly attenuated the HR, SBP, DBP, MBP and RPP following L&I compared to control. Metoprolol attenuated the heart rate and RPP compared to esmolol and labetalol. Esmolol attenuated the heart rate immediately following L&I better than labetalol and significantly attenuated the SBP at 5min and 10 min following L&I. All readings of RPP were lower in esmolol in comparison to labetalol. Esmolol, was better than labetalol in attenuating the hemodynamic response. Sinus tachycardia and hypotension were the common side effects. Three patients in control and one in labetalol group developed ectopic beats following L&I. One patient in esmolol had pain on i.v injection. Conclusion: Metoprolol attenuated the cardiovascular stress response to L&I in comparison to esmolol and labetalol. Esmolol was comparably better than labetalol. Metoprolol can be used as alternative to esmolol and labetalol.