A Comparative Study between Intra Venous Dexmedetomidine and Magnesium Sulfate in Attenuation of Cardiovascular Response to Laryngoscopy and Endotracheal Intubation – a Randomized Clinical Trial

Background and objective: The inappropriate response of hemodynamic parameters to endotracheal intubation (ETI) can increase perioperative and postoperative morbidity and mortality. Various pharmacological methods have been aimed to suppress this pressor response but the search for the ideal drug for attenuation of cardiovascular response during laryngoscopy and tracheal intubation continues. Dexmedetomidine is a highly selective α2 adrenoreceptor agonist and Magnesium sulfate (MgSO4) inhibits catecholamine release from adrenal glands and reduces levels of serum epinephrine and cause a decrease in the atrial contraction, bradycardia, and vasodilatation. The aim of this prospective randomised study is to compare effectiveness of Dexmedetomidine 1μg/kg and Magnesium sulfate 50mg/kg in attenuating cardiovascular response during laryngoscopy and intubation. Methodology: One hundred and two normotensive patients aged between 18-65 years, scheduled for elective surgical procedures belonging to ASA class I and II were included in study and randomly allocated into two groups. Group D (n=51): received Dexmedetomidine 1μg/kg diluted to 10 ml normal saline, intravenously over 10 minutes, 10 minutes before intubation. Group M (n=51) received Magnesium sulfate 50mg/Kg diluted to 10ml with normal saline, intravenously over 10 minutes, 10 minutes before intubation. After premedication, study drug was administered, anesthesia was induced with propofol till loss of verbal response followed by inj vecuronium 0.1mg/kg. 3min later, laryngoscopy and intubation were done with appropriate sized Mac Intosh blade and endotracheal tube. Hemodynamic parameters of patients including systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and heart rate (HR) were recorded immediately before anesthesia induction, before endotracheal intubation(ETI), immediately after ETI, and at second and fifth minutes after ETI. Results: It was noted that in group D the mean fall in HR, SBP,DBP and MAP at 2 and 5 minutes after intubation in Group D was statistically highly significant compared to the respective parameters in group M. Conclusion: Injection. Dexmedetomidine at 1μg/kg significantly attenuates hemodynamic response compared to magnesium sulfate 50mg/kg. Author Affiliations: 1,2 &3 Department of Anesthesiology, S. Nijalingappa Medical College, Bagalkot.