DP14: MANAGEMENT OF A PATIENT WITH RECURRENT INTRAOPERATIVE WIDENING OF QRS COMPLEX
Kristina R Casals, MD; Nathalie Abitbol, MD, MBA
University of Miami Jackson Health System
Introduction/Background: Perioperative arrythmias are clinically important as they can evolve into life threatening malignant arrythmias with severe hemodynamic instability and cardiovascular collapse if not recognized and addressed in a timely manner.
Methods: Patient is a 71-year-old female with a past medical history of well controlled hypertension and recurrent diverticulitis complicated by abscess formation scheduled to undergo sigmoidectomy. Pre-operative labs were normal, and no pre-operative cardiac testing was available in lieu of her excellent exercise tolerance. Shortly after standard induction of general anesthesia, the patient was noted to have widening of QRS complex at a rate of eighty to ninety beats per minute on five lead electrocardiogram (EKG).
Results: Initially, lead placement was checked and confirmed. Then, Esmolol was administered which reduced the heart rate to mid-seventies and resulted in conversion to sinus rhythm with a narrow QRS complex. The patient proceeded to flip spontaneously between a narrow complex QRS and widened QRS, seemingly developing the widened QRS only at a heart rate above seventy eight. Calcium gluconate was given, defibrillator pads were brought into the room, and procainamide was made available should the patient develop atrial fibrillation with the goal of avoiding beta blockers in the setting of possible undiagnosed Wolf Parkinson White (WPW) syndrome. Given the patients hemodynamic stability throughout, it was communicated to the surgeon that, despite the patients active EKG changes, surgery may proceed with a plan in place should the patient deteriorate. The case concluded uneventfully, and the patient was transferred to the post anesthesia recovery unit extubated where twelve lead EKG was obtained and cardiology consulted. Postoperative labs were unremarkable, and EKG showed a nonspecific intraventricular block, which she continued to exhibit throughout her admission. Echocardiogram was normal and no need for further intervention was identified.
Discussion/Conclusion: The differential diagnosis for a new onset widened QRS is broad and may be organized into pathologies of ventricular vs. supraventricular origin. An action potential originating in the ventricles outside of the proximal intrinsic conduction system may be due to a ventricular paced rhythm, ventricular tachycardia, or WPW syndrome. Conversely, an action potential originating above the ventricles that results in a widened QRS may be due to an abnormal conduction system (i.e., ischemia, left/right bundle branch block, nonspecific intraventricular conduction delay, cardiomyopathy) or abnormal conduction speed (i.e., hyperkalemia, sodium channel blockade secondary to medications or toxins, severe acidosis). Management involves reducing intraoperative strain on the cardiovascular system, minimizing hypoxia, hypovolemia and hypothermia, reviewing of patients medical history and medications, checking electrolytes, having medications to treat identifiable arrythmias readily available and avoiding medications that could worsen arrythmia (i.e., treatment with procainamide vs avoidance of beta blockers for fear of conduction via accessory pathway in WPW), and preparing for cardiopulmonary resuscitation and defibrillation or electrical cardioversion if needed. Patients may present to the operating room with new onset arrythmias with a broad differential diagnosis. Anesthesia providers should be ready to manage these changes should the patient deteriorate intraoperatively until evaluation by a cardiologist and/or electrophysiologist is possible.