Document Detail


The measurement of cardiac output by electrical impedance plethysmography in pregnancy. Are the assumptions valid?
MedLine Citation:
PMID:  3730343     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The assumptions of the Kubicek technique for measurement of cardiac output by detection of changes in the chest wall electrical impedance have been re-examined. The fall in cardiac output in the latter half of pregnancy which Crawford's group calculated using the Kubicek technique can be almost entirely accounted for by a fall in the term dZ/dT of the Kubicek equation, as pregnancy progress. One key assumption of the Kubicek technique is a constant ejection flow rate equal to the initial flow as the pulmonary valve opens, which is multiplied by the estimated ejection time to obtain stroke volume. Initial flow rate is represented by the term dZ/dT in the Kubicek equation. Although this assumption has been shown to give a reasonable correlation with other techniques for measurement of cardiac output in the non-pregnant state, this may not be so for longitudinal studies in pregnancy because of the changes in lung mechanics and in the circulation which occur in this state. Crawford's data emphasizes the necessity for validating the Kubicek technique very critically during pregnancy.
Authors:
M de Swiet; D G Talbert
Related Documents :
24711473 - Hellp syndrome preceded by intrahepatic cholestasis of pregnancy: one serious itch.
21895513 - The association between maternal alcohol use and smoking in early pregnancy and congeni...
7955653 - Sonography in early pregnancy failure.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  British journal of obstetrics and gynaecology     Volume:  93     ISSN:  0306-5456     ISO Abbreviation:  Br J Obstet Gynaecol     Publication Date:  1986 Jul 
Date Detail:
Created Date:  1986-09-17     Completed Date:  1986-09-17     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  7503752     Medline TA:  Br J Obstet Gynaecol     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  721-6     Citation Subset:  AIM; IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Cardiac Output
Cardiography, Impedance*
Female
Humans
Plethysmography, Impedance*
Pregnancy*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Analysis of impedance cardiography longitudinally applied in pregnancy.
Next Document:  Pregnancy in Jamaican women with homozygous sickle cell disease. Fetal and maternal outcome.