Methods and considerations concerning cardiac output measurement in pregnant women: recommendations of the International Working Group on Maternal Hemodynamics

Abstract

Cardiac output (CO), along with blood pressure and vascular resistance, is one of the most important parameters of maternal hemodynamic function. Substantial changes in CO occur in normal pregnancy and in most obstetric complications. With the development of several non‐invasive techniques for the measurement of CO, there is a growing interest in the determination of this parameter in pregnancy. These techniques were initially developed for use in critical‐care settings and were subsequently adopted in obstetrics, often without appropriate validation for use in pregnancy. In this article, methods and devices for the measurement of CO are described and compared, and recommendations are formulated for their use in pregnancy, with the aim of standardizing the assessment of CO and peripheral vascular resistance in clinical practice and research studies on maternal hemodynamics. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Preeclampsia: a gestational cardiorenal syndrome

“…; Bijl et al . ). To correctly interpret whether measured cardiac output is ‘high’ or ‘low’, one needs to consider what the appropriate or ‘normal’ cardiac output would be for maternal characteristics and gestational age – a process called indexing.…”

“…This hypothesis is further undermined by the interpretation of cardiac output indices independently of maternal morphological characteristics. Interpretation of maternal cardiac output in the majority of studies has been undertaken without taking into consideration maternal haemodynamic demands, which vary with height, weight, age and gestation (Vinayagam et al 2018;Perry et al 2018b;Bijl et al 2019). To correctly interpret whether measured cardiac output is 'high' or 'low' , one needs to consider what the appropriate or 'normal' cardiac output would be for maternal characteristics and gestational age -a process called indexing.…”

Evaluation of pulse wave transit time analysis for non-invasive cardiac output quantification in pregnant patients

“…Various approaches of haemodynamic monitoring under foetal surgery have been described ranging from absent CO monitoring to invasive CO measurement 1,4,5 . However, increasing evidence supports the importance of advanced haemodynamic monitoring including CO quantification in pregnant patients 6 . First, pregnancy leads to extensive changes to the maternal haemodynamic system which can hardly be precisely predicted under the anaesthetic conditions.…”

“…First, pregnancy leads to extensive changes to the maternal haemodynamic system which can hardly be precisely predicted under the anaesthetic conditions. Second, foetal surgery under general anaesthesia can induce rapid impairment of the maternal and foetal haemodynamic stability by changing intrathoracic (e.g., need for invasive ventilation) and intraabdominal pressure (e.g., partial amniotic carbon dioxide insufflation (PACI)) as well as decreasing the systemic vascular resistance (SVR) 1,[5][6][7] . Since no guidelines for the haemodynamic management of foetal surgery exist, the recommendations of the International Working Group of Maternal Haemodynamics have to be considered 6 .…”

“…Second, foetal surgery under general anaesthesia can induce rapid impairment of the maternal and foetal haemodynamic stability by changing intrathoracic (e.g., need for invasive ventilation) and intraabdominal pressure (e.g., partial amniotic carbon dioxide insufflation (PACI)) as well as decreasing the systemic vascular resistance (SVR) 1,[5][6][7] . Since no guidelines for the haemodynamic management of foetal surgery exist, the recommendations of the International Working Group of Maternal Haemodynamics have to be considered 6 . The authors of these recommendations highlight the need for individual assessment of advanced haemodynamic monitoring (including CO measurement) in pregnant patients as well as individual definitions of thresholds of the measured haemodynamic parameters.…”