uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Gender and age differences in thoracic bioimpedance
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
1997 (English)In: Acta Physiologica Scandinavica, ISSN 0001-6772, E-ISSN 1365-201X, Vol. 161, no 2, 171-175 p.Article in journal (Refereed) Published
Abstract [en]

Thoracic impedance consists of a constant baseline component Z0 and a time-variable component delta Z which represents the impedance change related to the cardiac cycle. The maximum part of delta Z [(dZ/dt)max] represents the peak of the ascending aortic blood flow. Measurements of basal thoracic impedance are affected by structural and anatomical differences in the thorax related to sex and ageing. This component is a variable in the denominator of Sramek's formula which is used for calculating stroke volume. The aim of this study was to elucidate the question as to whether the age- and sex-related variation in basal impedance may affect bioimpedance measurements of stroke volume. The study comprised 111 healthy subjects (55 males and 56 females) of ages between 20 and 69 years, divided according to age decades into five groups each of males and females. Stroke volume index (SI), Z0 and (dZ/dt)max were measured in every subject, using transthoracic bioimpedance cardiography. Z0 and (dZ/dt)max had significantly higher values in females than in males in every age group except the oldest one in the case of Z0 and the oldest two groups in the case of (dZ/dt)max. Stroke index showed no significant sex difference, although the higher Z0 in females may underestimate the values of stroke index. Elevation of (dZ/dt)max in females may therefore reflect a positive relation to Z0 rather than higher flow rates. Since Z0 and (dZ/dt)max are variants in opposite positions in Sramek's formula (denominator and numerator, respectively), this functional relationship may keep the bioimpedance measurements from being affected by the sex- and age-related changes in Z0.

Place, publisher, year, edition, pages
1997. Vol. 161, no 2, 171-175 p.
National Category
Medical and Health Sciences
Identifiers
URN: urn:nbn:se:uu:diva-55311DOI: 10.1046/j.1365-201X.1997.d01-1949.xPubMedID: 9366959OAI: oai:DiVA.org:uu-55311DiVA: diva2:83219
Available from: 2008-10-17 Created: 2008-10-17 Last updated: 2017-12-04Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed
By organisation
Department of Medical Sciences
In the same journal
Acta Physiologica Scandinavica
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 361 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf