Obstetrics/Gynecology

Positioning During Labor

During the intrapartum period of pregnancy, prolonged positioning in supine position can severely impede venous return. This causes supine hypotension which can lead to tachycardia and other compensatory actions that should be avoided especially in patients with cardiac compromise. Supine hypotension syndrome can decrease cardiac output by 30 to 40 percent. [1] Women with cardiac disease are asked to labor while lying on their left side. However, many times repositioning efforts by the patient (even with assistance from medical staff) do not result in relieving compression on the vena cava. One potential use of the EC monitors during labor would be in determining the optimum position for intrapartum cardiac patients in regards to CO. Clinicians would be able to see the patients CO increase once the patient is positioned in a manner that truly relieves the vena cava in real time on the EC monitor. [2]

Maintenance of Intravascular Fluid Volume throughout Labor and Birth

Accurate assessment and monitoring of intravascular fluid volume throughout labor and birth is essential in women with cardiac disease. In general, intravascular depletion should be avoided in women with defects in left ventricular filling. However, women with obstructive lesions, such as mitral or aortic stenosis or pulmonary hypertension, may require hydration to optimize left ventricular preload and cardiac output. [4] Fluid management in these cases is directed at avoiding fluid overload and possibly restricting fluids. By monitoring the patient with the EC monitors during a fluid challenge test, the measured stroke volume and stroke volume variation can be used to determine where the patient is on the Frank-Starling curve (wet or dry).

Regional Anesthesia during Labor

Monitoring cardiac patients who are given regional anesthesia is very critical. If the patient is not closely monitored, a rapid onset, high-level spinal block can drastically reduce cardiac output by reducing venous return through peripheral vasodilation and by blocking the cardiac sympathetic supply. [3] Using the EC monitors, patients can be properly monitored so that no time is wasted if CO does fall rapidly.

Maintenance of Intravascular Fluid Volume throughout Labor and Birth

Accurate assessment and monitoring of intravascular fluid volume throughout labor and birth is essential in women with cardiac disease. In general, intravascular depletion should be avoided in women with defects in left ventricular filling. However, women with obstructive lesions, such as mitral stenosis, aortic stenosis or pulmonary hypertension, may require hydration to optimize left ventricular preload and cardiac output. [4] Fluid management in these cases are directed at avoiding fluid overload and possibly restricting fluids. By conducting a passive leg raise test on the patient while monitoring with an ICON or AESCULON, the resulting change in stroke volume with the leg raised (from baseline) would allow the clinician to get a better idea of where the patient is on the Frank-Starling curve.

The Immediate Postpartum Period

The immediate postpartum period is a time of increased vulnerability for many women, especially those with fixed cardiac output who are unable to accommodate the systemic redistribution of cardiac output following expulsion of the placenta. [3] Since the EC monitors are completely non-invasive, hemodynamic monitoring can be conducted from the beginning to the end of the postpartum period.

EC Demonstrates Heart Failure and Recovery After Delivery by Tom Archer et al. [5]

Abstract:

A patient with von Willebrand’s Disease, type 2b and inadvertent preoperative iatrogenic fluid overload underwent cesarean section under general anesthesia. Shortly after delivery, hypoxemia, diffuse rales and wheezing developed. Electrical Cardiometry, a new method for measuring hemodynamics non-invasively, demonstrated decreased stroke and cardiac indices, corroborating a diagnosis of acute left ventricular failure. The patient was diuresed and her clinical picture and hemodynamic parameters improved. Electrical Cardiometry is a promising non-invasive technology for estimating stroke volume and cardiac output in an awake parturient.


[1] Feingold, H. (2003). Cardiac Arrest in Labor and Delivery: A Current Review. Society of Obstetric Anesthesia and Perinatology Newsletter.

[2] Salmon, N. (2011). Managing Cardiac Conditions during Labor and Delivery. RN.com.

[3] P. Steer, e. a. (2006). Heart Disease and Pregnancy. The Royal College of Obstetricians and Gynecologist, 285-294.

[4] MR., F. (2004). Cardiac Disease. Critical Care Obstetrics, 252-274.

[5] Tom Archer, M. (2011). Electrical Cardiometry demonstrates heartfailure and recovery after delivery. SOAP Annual Meeting.