Which of the following is not used in controlling hea rate intraoperatively.

B i.e. Verapamil Intraoperative administration of intravenous blockers (atenolol, metoprolol, propranolol or esmolol)Q is done to avoid tachycardia during induction of anesthesia. The onset of paroxysmal atrial tachycardia or fibrillation in perioperative period can be treated by the iv administration of drug that abruptly prolong the refractory period of AV node (adenosine) or lengthen the refractory period of accessory pathways (procainamide)Q Digitalis and verapamil may decrease refractory period of accessory pathways (in pre-excitation syndromes like Wolff-Parkinson-White syndrome) responsible for atrial fibrillation and thereby result in an increase in ventricular response rate during this dysrhythmia and thus should be avoided. Ventricular tachycardia not a/ w hypotension is initially treated by iv administration of lidocaine, amiodarone or lidocaine, amiodarone or procainamide. Symptomatic VT is best treated by external electrical cardioversion.