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

Non-invasive cardiac output monitoring (NICOM) in a patient with cardiomyopathy secondary to Marfan syndrome undergoing cesarean section

Abstract Number: F-75
Abstract Type: Case Report/Case Series

Steven D Beaudry D.O.1 ; Jeremy S Pick M.D.2

Introduction: Parturients with cardiomyopathy are at risk of heart failure from increased circulating blood volume during cesarean section (CS). Mean arterial blood pressure (MAP) trends do not directly measure changes in cardiac output (CO) or stroke volume (SV). NICOM (Cheetah Medial Inc, Newton Center, MA) is a non-invasive external monitor that uses bioreactance to measure SV and is a valuable adjunctive monitor for high-risk parturients(1,2).

Case: A 24 year-old G1P0 woman with Marfan syndrome (MFS) s/p aortic arch and aortic valve (AV) replacements presented at 34 weeks gestation with an EF of 37% and an AV thrombus. Heparin infusion was started and she was scheduled for CS. We utilized NICOM as an adjunctive monitor for hemodynamic management. To our knowledge, NICOM use during CS under epidural anesthesia with maternal cardiomyopathy has not been reported. After discontinuing heparin, a L4-5 epidural catheter, radial arterial line, and two 18-gauge peripheral IVs were placed in the OR. After positioning supine with uterine displacement, NICOM electrodes were placed and CO/SV data taken every minute. The epidural was dosed incrementally with 20mL of 2% lidocaine to a T4 level. IV fluids were limited to 30 mL/hr after a 700 mL load during epidural placement. Baseline CO and SV were 6.5 L/min and 71 mL respectively.

Discussion: Three major hemodynamic trends were noted. CO and SV increased 31% and 49% from epidural dosing to incision, likely from anesthetic-induced decreased systemic resistance (Figure 1A). CO/SV then steadily declined back to near baseline despite a transient 6% increase in the first minute after delivery. Oxytocin (20 units/1L) was infused just after delivery and continued throughout the case. At 18 minutes post-delivery, CO/SV started trending up significantly to final values of 10.4 L/min and 126 mL, 60% and 77% above baseline. MAP was labile and HR trended down throughout the case (Figure 1B). Total IV fluid given was 1,700 mL and blood loss was 800 mL. She remained stable and did not develop signs of acute volume overload. CO correlated strongly with SV (r=0.96) suggesting that her myocardial contractile function was intact despite her cardiomyopathy. Titrating phenylephrine to maintain MAP did not appear to significantly improve CO. NICOM provides better insight into myocardial performance during CS than arterial blood pressure and HR monitoring alone.

1. Fanning N, J Can Anesth 2011

2. Lorello G, Int J Obstet Anesth 2014

SOAP 2015