Ventricular Bigeminy Case Study

Immediate post-operative ventricular bigeminy in a patient posted for ovarian cystectomy – A case report.
Introduction
Ventricular Bigeminy is a type of ventricular premature complex (VPC) where every normal sinus beat is followed by a ventricular ectopic. The characteristic feature here is wide QRS (0.14s) complexes with abnormal ST-T changes followed by a long pause. Ventricular arrhythmias are among the commonest arrhythmias that occurs in patient with or without heart disease.The peripheral pulse associated with such episodes is known as pulsus bigeminus. The most feared complication is its potential to develop into ventricular fibrillation and asystole. Hypokalemia and light plane of anaesthesia are some of the few correctable causes of
Recovery was normal with eye opening and the patient was responding to oral commands. The vitals of the patient was also normal with heart rate of 64 /min and blood pressure around 100/60 mmHg. When she was about to be shifted to post operative recovery ward, ventricular ectopics started. Initially there was 5 to 6 ventricular ectopic beats/min which gradually progressed to ventricular bigeminy. There was also small periods of normal sinus rhythm without any ventricular ectopics when the heart rate was around 45-50/min. During the ventricular bigeminy the heart rate almost doubled to around 90-100/min. Immediately 60 mg of 2% lignocaine i.v was given to the patient but proved futile in controlling the ectopic. After 5 min, 1mg of metoprolol was given and immediately the frequency of the ventricular ectopics came down to 5-6/min. Again 1mg metoprololi.v was repeated which completely stopped the ectopics. The patient was completely reverted to sinus rhythm within 10 min.All this time the patient was conscious and was obeying oral commands. The patient was shifted to the ICU and was monitored for 2 days for any signs of ectopics. Luckily there was no incidence of ventricular ectopic or bigeminy in that period. The serum potassium levels was found to around 3.6 meq/L in the immediate post operative period. She was shifted to post operative ward on the third day and was discharged on the 7thpost operative
Volatile agents increases the conduction time through the Bundle of His and Purkinje system thereby facilitating re-entry phenomenon.[5] There is stimulation of alpha 1 adrenergic receptors especially in the heart which results in the sensitization of the sympathetic receptors to the catecholamines and facilitates arrhythmia.[6] Occulo cardiac reflex, a variant of Trigeminocardiac reflex (TCR) is also reported to cause Venticular bigeminy.[7,8] Surya kumar et al reported in their case by an increase in the ICP caused due to Valsalva Manoeuvre triggered TCR which due to stimulation of trigeminal nucleus caused the ventricular bigeminy.[9] Any disturbance in the potassium balance causes cardiac arrhythmia.[10,11] Prominent U waves along with ST segment and T wave depression is a significant sign of hypokalemia.[12] In a hypokalemic patient, hyperventilation leads to respiratory alkalosis precipitating arrhythmias by further reducing potassium.[4] Hypokalaemia treatment has lead to the reversal of ventricular bigeminy as observed by Ganny et al in their case report.[4] But Wong et al have differed by not committing hypokalaemia as an independent risk factor for cardiac