Attenuation of Hemodynamic Responses to Endotracheal Extubation with Different Doses of Diltiazem with Lignocaine: A Placebo-Controlled Study.

Introduction: Endotracheal extubation causes transient hemodynamic stimulation leading to increase in blood pressure and heart rate (HR) due to increase in sympathoadrenergic activity caused by epipharyngeal and laryngopharyngeal stimulation. Lignocaine, a sodium channel blocker, attenuates the hemodynamic response to tracheal extubation by inhibiting sodium channels in the neuronal cell membrane, decreasing the sensitivity of the heart muscles to electric impulses. Diltiazem, a calcium channel blocker, attenuates hemodynamic response by blocking voltage-sensitive L type channels and inhibiting calcium entry-mediated action potential in smooth and cardiac muscle.

Aims And Objectives: The aims and objectives of this are to study and to compare the efficacy of combination of intravenous (i.v.) diltiazem 0.1 mg/kg and i.v. lidocaine 1.0 mg/kg, diltiazem 0.2 mg/kg and lidocaine 1.0 mg/kg, lignocaine 1.0 mg/kg with normal saline given to attenuate exaggerated hemodynamic extubation responses and airway reflexes during extubation.

Materials And Methods: This study was undertaken with 105 patients belonging to the age group 20-65 years with physical status ASA Classes I and II of either sex. Group A received injection diltiazem 0.1 mg/kg and preservative-free lignocaine 1 mg/kg. Group B received injection diltiazem 0.2 mg/kg and lignocaine 1 mg/kg. Group C received injection lignocaine 1 mg/kg with normal saline. In this study group, the drug dosage was fixed based on the previous studies.

Results: At postextubation, significant difference in HR, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) were observed from 1 to 10 min between three groups. The difference in HR, SBP, DBP, and MAP were statistically significant between Group C in comparison with Group A and Group B from 1 min postextubation to 10 min.

Conclusion: Combined diltiazem and lidocaine are more effective prophylaxis than lidocaine alone for attenuating the cardiovascular responses to tracheal extubation.