///2015 Abstract Details
2015 Abstract Details2019-08-02T16:54:43-06:00

“Otherwise Healthy…” An Ascending Aortic Aneurysm Diagnosed at Term

Abstract Number: F-81
Abstract Type: Case Report/Case Series

Yefim Vilnits MD1 ; Marie-Louise Meng MD2; Richard Smiley MD, PhD3

Intro: Aortic root dilation is one of the most feared cardiovascular changes in pregnancy. Peripartum hemodynamic control is essential to prevent further aortic dilation or rupture. Cesarean delivery (CD) performed prior to the initiation of spontaneous labor is the recommended delivery mode for patients with aortic diameters >4.5cm 1,2.

Case: A 29yo G2P0 at 39 weeks presented to a community hospital with decreased fetal movement. Throughout pregnancy, BP had always been measured on the left arm with readings ~100/60. History was notable for MVA (blunt left arm and chest trauma) 5 years prior to presentation and Harrington rod placement at age 16 for scoliosis. Review of systems was negative except for occasional left arm weakness. At presentation, right arm BP was 200/100, left arm BP 110/60, Mallampati class IV. Calf BP was 210/100. CT revealed a 5cm ascending aortic aneurysm with near occlusion of the left common carotid (LCC) and left subclavian (LSC) arteries. She was transferred to our medical center. Echocardiography revealed severe concentric LVH suggestive of long standing HTN. PEC labs were normal.

CD was done in a CT OR with spinal anesthesia (SA) (bupivacaine 12mg, fentanyl 20 mcg, morphine 0.2mg) with the chest prepped and CT surgery/perfusion on stand-by. BP decreased appropriately after the SA and a phenylephrine infusion was used to maintain SBP 90 to 120 (monitored via R radial arterial line). Esmolol infusion was at 500mcg/kg/min to maintain HR <70. An infant with Apgar 6, 9 was delivered. The patient was transferred to the surgical ICU for continued BP control. CTA demonstrated arterial wall thickening suggestive of Takayasu’s arteritis. Aortic repair was scheduled for 6 weeks after delivery.

Discussion: Diagnosis of an aortic aneurysm obstructing flow to the LCC and LSC arteries was worrisome for impending aortic dissection, rupture or cerebrovascular accident. The patient likely had chronic HTN due to poor flow to the left carotid sinus resulting in systemic catecholamine release. Regional anesthesia (RA) was preferred over general anesthesia (GA) for several reasons, including the class IV airway. Induction of GA and intubation can cause hemodynamic instability that can lead to aortic dissection. Given the LCC artery occlusion, the mental status of the patient served as an assessment of cerebral perfusion in the presence of the relative hypotension tolerated to avoid aortic shear stress. Combined spinal-epidural anesthesia was considered so as to avoid conversion to GA in an emergent, non-controlled setting. However, epidural catheters can be unreliable in patients with Harrington rods 3. SA was deemed to be the best option for dense, reliable surgical anesthesia, especially with the anatomic spinal abnormality. Aggressive hemodynamic control prevented further aortic compromise during the peripartum period.

References:

1. Cox. Arch Gyn Ob. 2014

2. Hagen. Best Pract Res Clin Ob Gyn. 2014

3. Crosby. Can J Anaesth. 1989

SOAP 2015