Successful Epidural Anesthesia for Cesarean Section in a Parturient with Unrepaired Pulmonary Atresia and a Ventricular Septal Defect
Abstract Number: F-41
Abstract Type: Case Report/Case Series
The cardiovascular physiologic changes that occur during pregnancy and delivery, such as increased Stroke volume, progesterone mediated vasodilation, decreased SVR, and anemia, present a unique challenge in management of patients with congenital cyanotic cardiac lesions. We report the successful anesthetic management of parturient with unrepaired Pulmonary Atresia and a Ventricular Septal Defect. The patient was diagnosed at birth and underwent two unsuccessful Blalock-Taussig (B-T) Shunts within her first week of life with no subsequent cardiac surgery. A TTE at 15 weeks gestation demonstrated pulmonary atresia and a VSD, with severe hypoplastic pulmonary arteries with bronchial collaterals from the aorta and moderate aortic regurgitation. Prior to pregnancy the patient oxygen saturations were 60-70%, improving to approximately 80% with oxygen therapy. Secondary polycythemia due to chronic hypoxia resulted in a hemoglobin of 19.5g/dL and a hematocrit of 57.9g/dL. She had very limited exercise tolerance and slept sitting up. She was admitted at 35 weeks gestation from high risk obstetric clinic with an oxygen saturation of 82%, hemoglobin of 14.7g/dL, hematocrit of 43.6 g/dL and an INR of 1.1. She was scheduled for Cesarean Section at 37 weeks gestation. After receiving multiple packed red blood cell transfusions to elevate hemoglobin in anticipation of surgical blood loss, the patient was transported to the OR, standard monitors were applied, an arterial line was placed, and both pre and post lesion oxygen saturations were monitored. Saturations on the right hand and left foot, respectively, were 75% and 80%. An epidural catheter was then placed at L4-L5 and titrated to allow placement of bilateral venous femoral sheaths in the event rapid institution of veno-veno extracorporeal membrane oxygenation (ECMO) if oxygen saturation fell to unacceptable levels. After achievement of surgical block, the surgery proceeded as planned with the patient hemodynamically stable throughout. Blood pressure ranged from 120-160/65-75. With titration of the epidural, a slight decrease in blood pressure and SVR were noted (SBP decrease from 140 to 120). A reversal in shunt fraction in the pre and post lesion were noted, with oxygen saturations in the right hand increasing to 80% and the left foot decreasing to 75%. The remainder of the case proceeded uneventfully and the patient was transported to the Pediatric Intensive Care Unit (PICU) in stable condition. Upon removal of her epidural, she was started on a heparin infusion that was transitioned to Lovenox prior to discharge. Her oxygen saturations averaged 78% in the PICU, her pain was well managed with Percoceet and on Post Operative Day 3 she was discharged to home. At 6 week followup, the patient, despite stopping her Lovenox treatment, was doing well and had demonstrated improved exercise tolerance with maintenance of pre-pregnancy oxygen saturation levels.