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.