///2010 Abstract Details
2010 Abstract Details2019-08-03T15:49:10-05:00

Anesthetic Management of Cesarean Section in a Parturient with Shones Syndrome

Abstract Number: 172
Abstract Type: Case Report/Case Series

James Y Ko M.D., M.P.H.1 ; Andrea Torri M.D.2

Shone's syndrome is characterized by congenital cardiac anomalies involving up to four obstructive left-sided lesions: aortic coarctation, subaortic stenosis, mitral valve parachute deformity, and supravalvular mitral ring. We report on the anesthetic management of a 26 y/o nullipara with Shones syndrome and moderate obesity (BMI = 35.4) who presented for elective cesarean delivery at 38 WGA.

Her cardiac lesions included mild/moderate aortic coarctation, subaortic stenosis, and mild LVOT obstruction. She was closely followed throughout pregnancy by a multidisciplinary team including the high-risk OB service, OB Anesthesia, and Cardiology. Cesarean delivery was planned to avoid prolonged hemodynamic stress associated with spontaneous vaginal delivery and the risk of aortic dissection. A cardiac MRI before her scheduled cesarean section was negative for aortic dissection. Our hemodynamic goals included maintenance of perfusion to all relevant organ systems, including placental perfusion, balanced with avoidance of systemic hypertension, which would increase the risk of dissection. Given her mild degree of LVOT obstruction, we planned to avoid the use of ephedrine and inotropic agents, as they could worsen the LVOT obstruction and systemic perfusion.

A radial arterial line was inserted and transduced before the uneventful placement of a lumbar epidural catheter. Initial testing with 3 ml of 1.5% lidocaine ruled out accidental intrathecal placement. We started a small bolus infusion of the epidural with 2% lidocaine with epinephrine. After about 5 minutes and a total dose of only 10 ml of 2% lidocaine with epinephrine, we observed and recorded a profound hemodynamic response. The patients heart rate decreased from the low 100s bpm to 50s bpm, and her systolic blood pressure dropped from the 140s mmHg to 80-90s mmHg. No ST changes were noted on EKG, but the patient did complain of some transient mild chest discomfort and labored breathing. Her hypotension, bradycardia and symptoms resolved within 1 minute after the immediate administration of IV phenylephrine and glycopyrrolate. She achieved a bilateral T4 level to pain from this small dose of 2% lidocaine and the cesarean section proceeded without difficulty. A healthy male infant was delivered with APGARs of 8, 8. We continued close intraoperative monitoring and after the end of the surgery the patient was transferred to a monitored unit bed.

The degree of hypotension and bradycardia observed is unusual after 10 ml of 2% lidocaine in the epidural space. The presence of aortic coarctation and stenosis is likely the cause of this intense hemodynamic effect. Our continuous monitoring of systemic blood pressure by a radial arterial line guided the most prompt correction of the hypotension after a total epidural dose of lidocaine which was 50% smaller than usual.

SOAP 2010