title: Validation of maternal cardiac output assessed by transthoracic echocardiography against pulmonary artery catheterization in severely ill pregnant women: prospective comparative study and systematic review.
abstract: OBJECTIVE
  Most severe pregnancy complications are characterized by profound hemodynamic disturbances, thus there is a need for validated hemodynamic monitoring systems for pregnant women. Pulmonary artery catheterization (PAC) using thermodilution is the clinical gold standard for the measurement of cardiac output (CO), however this reference method is rarely performed owing to its invasive nature. Transthoracic echocardiography (TTE) allows non-invasive determination of CO. We aimed to validate TTE against PAC for the determination of CO in severely ill pregnant women.
  
  
  METHODS
  This study consisted of a meta-analysis combining data from a prospective study and a systematic review. The prospective arm was conducted in Pretoria, South Africa, in 2003. Women with severe pregnancy complications requiring invasive monitoring with PAC according to contemporary guidelines were included. TTE was performed within 15 min of PAC and the investigator was blinded to the PAC measurements. Comparative measurements were extracted from similar studies retrieved from a systematic review of the literature and added to a database. Simultaneous CO measurements by TTE and PAC were compared. Agreement between methods was assessed using Bland-Altman statistics and intraclass correlation coefficients (ICC).
  
  
  RESULTS
  Thirty-four comparative measurements were included in the meta-analysis. Mean CO values obtained by PAC and TTE were 7.39 L/min and 7.18 L/min, respectively. The bias was 0.21 L/min with lower and upper limits of agreement of -1.18 L/min and 1.60 L/min, percentage error was 19.1%, and ICC between the two methods was 0.94.
  
  
  CONCLUSIONS
  CO measurements by TTE show excellent agreement with those obtained by PAC in pregnant women. Given its non-invasive nature and availability, TTE could be considered as a reference for the validation of other CO techniques in pregnant women. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.
  Las complicaciones del embarazo más graves se caracterizan por trastornos hemodinámicos serios, debido a los cuales existe la necesidad de sistemas validados de monitorización hemodinámica para mujeres embarazadas. Aunque la cateterización de la arteria pulmonar (CAP) mediante termodilución es el patrón de referencia clínico para la medición del gasto cardíaco (GC), este método se usa con poca frecuencia debido a su naturaleza invasiva. La ecocardiografía transtorácica (ETT) permite la determinación no invasiva del GC. El objetivo de este estudio fue validar la ETT frente al CAP para determinar el GC en mujeres embarazadas gravemente enfermas. MÉTODOS: Este estudio consistió en un metaanálisis que combinó datos de un estudio prospectivo y una revisión sistemática. El estudio prospectivo se llevó a cabo en Pretoria (Sudáfrica) en 2003. Se incluyeron mujeres con complicaciones graves en el embarazo que requerían una monitorización invasiva mediante CAP según las directrices de ese momento. Se realizó una ETT en un plazo de 15 minutos de haber realizado el CAP y el investigador no tuvo acceso a las mediciones del CAP. Las mediciones comparativas se extrajeron de estudios similares obtenidos a partir de una revisión sistemática de la literatura y se añadieron a una base de datos. Se compararon las mediciones simultáneas del GC mediante ETT y CAP. La concordancia entre métodos se evaluó a través del método estadístico de Bland-Altman y de coeficientes de correlación intraclase (CCI).
  
  
  RESULTS
  Se incluyeron treinta y cuatro mediciones comparativas en el metaanálisis. Los valores medios del GC obtenidos mediante CAP y ETT fueron de 7,39 l/min y 7.18 l/min, respectivamente. El sesgo fue de 0,21 l/min, siendo los límites inferior y superior de la concordancia de -1,18 l/min y 1.60 l/min; el error porcentual fue del 19,1%, y el CCI entre ambos métodos fue de 0,94.
  
  
  CONCLUSIONS
  Las mediciones del GC en mujeres embarazadas mediante ETT muestran una excelente concordancia con las obtenidas mediante CAP. Dada su naturaleza no invasiva y su disponibilidad, la ETT podría considerarse como referencia para la validación de otras técnicas relacionadas con el GC en mujeres embarazadas. : ,。(pulmonary artery catheterization,PAC)(cardiac output,CO),,。(transthoracic echocardiography,TTE)CO。PACTTECO。 : meta。2003。PAC。PAC 15 minTTE,PAC。,。TTEPACCO。Bland-Altman(intraclass correlation coefficients,ICC)。 : meta34。PACTTECO7.39 L/min7.18 L/min。-1.18 L/min、1.60 L/min0.21 L/min,19.1%,ICC0.94。 : TTECOPACCO。,TTECO。.
authors.affiliation: Department of Obstetrics and Gynecology, Kalafong Provincial Tertiary Hospital University of Pretoria, Pretoria, South Africa.|Department of Obstetrics & Gynecology, Erasmus MC University Medical Center, Rotterdam, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Cornette
authors.affiliation: Department of Obstetrics and Gynecology, Kalafong Provincial Tertiary Hospital University of Pretoria, Pretoria, South Africa.|Department of Obstetrics and Gynecology, Kloof Mediclinic, Gauteng, South Africa.
authors.forename: S
authors.initials: S
authors.lastname: Laker
authors.affiliation: Department of Obstetrics and Gynecology, Kalafong Provincial Tertiary Hospital University of Pretoria, Pretoria, South Africa.|Department of Obstetrics and Gynecology, Joondalup Health Campus, Joondalup, Western Australia, Australia.
authors.forename: B
authors.initials: B
authors.lastname: Jeffery
authors.affiliation: Department of Obstetrics and Gynecology, Kalafong Provincial Tertiary Hospital University of Pretoria, Pretoria, South Africa.|Department of Obstetrics and Gynecology, University of Witwatersrand, Gauteng, South Africa.
authors.forename: H
authors.initials: H
authors.lastname: Lombaard
authors.affiliation: Department of Anesthesiology and Critical Care, Kalafong Provincial Tertiary Hospital University of Pretoria, Pretoria, South Africa.
authors.forename: A
authors.initials: A
authors.lastname: Alberts
authors.affiliation: Department of Biostatistics, Erasmus MC University Medical Center, Rotterdam, The Netherlands.
authors.forename: D
authors.initials: D
authors.lastname: Rizopoulos
authors.affiliation: Department of Cardiology, Erasmus MC University Medical Center, Rotterdam, The Netherlands.
authors.forename: J W
authors.initials: JW
authors.lastname: Roos-Hesselink
authors.affiliation: Department of Obstetrics and Gynecology, Kalafong Provincial Tertiary Hospital University of Pretoria, Pretoria, South Africa.
authors.forename: R C
authors.initials: RC
authors.lastname: Pattinson
mesh_terms: D000293:Adolescent; D000328:Adult; D002302:Cardiac Output / Q000502:physiology*; D002407:Catheterization, Swan-Ganz / Q000379:methods*; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D011247:Pregnancy; D011446:Prospective Studies; D013019:South Africa; D055815:Young Adult
keywords: Swan-Ganz; cardiac output; pregnancy; pulmonary artery catheter; systematic review; transthoracic echocardiography