///2009 Abstract Details
2009 Abstract Details2018-05-01T17:45:11+00:00

Combined Spinal Epidural Anesthesia for Cesarean Section in a Patient with a History of Acquired Long QT Syndrome (LQTS)

Abstract Number: 235
Abstract Type: Case Report/Case Series

Tien Thach MD1 ; Amy Lee MD2; Cynthia Wong MD3

INTRODUCTION: Long QT syndrome (LQTS) is a disorder characterized by a prolongation of the QT interval on ECG, and a propensity towards ventricular tachyarrhythmias, including the polymorphic ventricular tachycardia known as Torsade de Pointes. The prolonged QT interval represents delayed repolarization secondary to dysfunction of cardiac ion channels. LQTS can be congenital or acquired. Stressors, such as surgery, can provoke ventricular tachyarrhythmias, causing syncope or cardiac arrest. We report the case of a parturient with a history of drug-induced LQTS who underwent cesarean delivery under combined spinal-epidural (CSE) anesthesia. CASE STUDY: A 35 year-old multiparous woman, with a history of drug-induced LQTS and Torsades de Pointes, was scheduled for a repeat cesarean delivery at 39 weeks gestation. Her past medical history included a PDA for which she had percutaneous closure, complicated by the development of SA nodal dysfunction requiring AAI pacemaker placement. She had two previous cesarean deliveries for fetal intolerance of labor and complete previa. She had no episodes of cardiac arrythmias during her pregnancy. Pre-operatively, she was found to be in hemodynamically stable atrial fibrillation, with a heart rate in the 80s. Pacemaker interrogation was performed, and the pacemaker was left in the AAI mode. The patient received pharmacologic aspiration prophylaxis, routine ASA monitors were placed, and an external AED was immediately available. CSE anesthesia was initiated using a loss-of-resistance, needle-through-needle technique with a 17-g Touhy and 27-g spinal needle. An intrathecal injection of hyperbaric bupivacaine 12 mg with fentanyl 15 g and morphine 150 g was administered prior to threading the epidural catheter. Intrathecal epinephrine was not used as adjunct to avoid potentiating any dysrhythmias. The patient had four hypotensive episodes, which were successfully treated with phenylephrine. DISCUSSION: Case reports suggest that pregnancy increases the risk of tachyarrhythmias in normal healthy patients (1). Women with preexisting dysrhythmias may be at higher risk. Anesthetic management in LQTS is aimed towards the prevention of prolongation of the QT interval and tachyarrhythmias. Agents that can induce either should be avoided. Sudden sympathetic adrenergic stimulation should be minimized because it can trigger ventricular tachyarrhythmias. The first case report of spinal anesthesia for cesarean section in a parturient with LQTS was in 2004 (2). The advantage of neuraxial anesthesia in LQTS is the blunting of sympathetic stimulation and the resultant adrenergic surge that occurs with the stress of surgery. Although spinal anesthesia may cause profound hypotension due to this sympathectomy and result in arrhythmia and cardiac arrest, successful treatment with a non-arrhythmogenic agent made this technique safe in our parturient with LQTS.

1 Can J Anesth 2007; 54:561-572.

2 Can J Anesth 2004; 51:993-996

SOAP 2009