Abstract Introduction: Laryngoscopy and intubation of trachea are integral part of general anesthesia which can trigger adverse hemodynamic responses. These are unpredictable reflex sympathetic stimulations that may cause tachycardia, hypertension and arrhythmias. These short duration responses get amplified in high risk patients with likelihood of even pulmonary oedema and cerebrovascular accidents. These responses can be blunted by means like drugs and nerve blocks. Our study was designed to compare actions of intravenous (IV) esmolol (1mg/kg) and ditiazem (0.2mg/kg) to attenuate these responses. Material and Methods: 80 consenting, ASA I/II adults posted for elective noncardiac, non neurologic operations were included in this randomised, double blinded, clinical comparative study. Parameters recorded were ECG, heart rate (HR), systolic BP (SBP), diastolic BP (DBP), mean arterial BP (MAP), ST segment values, SpO2, arrhythmia analysis and incidence of any required rescue medication. Baseline values (mean of three readings, 1 minute apart) of HR, SBP, DBP, MAP, ST segment and SpO2 were recorded before induction of anesthesia. General anesthesia was given and study drug was injected 1 min. after muscle relaxant and intubation was done 2 min. thereafter. Abovesaid parameter values were recorded at intubation and every minute thereafter, till 10 min. postintubation. Effects were statistically analysed. Statistical analysis and results: Unpaired ttest and generalized estimation equation were used for quantitative variables (e.g. HR, BP) to compare mean levels at different times points between two groups. Paired ttest was used for determining significance within the group at different time points. Chisquare/Fischer exact test (for categorical variable like arrhythmia) and nonparametric Mannwhitney test (in case data did not follow normal distribution) were planned,but were not required. Results: Both drugs control the heart rate well. Esmolol controls it better. At 10 minutes after intubation both achieve similar HR values. Both drugs control the SBP, DBP and MAP. Diltiazem controls it better. At 10 min. after intubation, both achieve similar BP values. Both drugs safely attenuate hemodynamic response to laryngoscopy and
intubation, as there were no arrhythmias, ST changes of significance or requirements of rescue medications in any patient.