Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Cardiac output determinations with ear piece densitometry.

G Hedenstierna, B Schildt

    Upsala Journal of Medical Sciences
    |January 1, 1975
    PubMed
    Summary
    This summary is machine-generated.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    Effect of Intraoperative High Positive End-Expiratory Pressure (PEEP) With Recruitment Maneuvers vs Low PEEP on Postoperative Pulmonary Complications in Obese Patients: A Randomized Clinical Trial.

    JAMA·2019
    Same author

    Tidal changes in PaO<sub>2</sub> and their relationship to cyclical lung recruitment/derecruitment in a porcine lung injury model.

    British journal of anaesthesia·2019
    Same author

    Specific anesthesia-induced lung volume changes from induction to emergence: a pilot study.

    Acta anaesthesiologica Scandinavica·2017
    Same author

    Atelectasis is inversely proportional to transpulmonary pressure during weaning from ventilator support in a large animal model.

    Acta anaesthesiologica Scandinavica·2017
    Same author

    Erratum to Protective intraoperative ventilation with higher versus lower levels of positive end-expiratory pressure in obese patients (PROBESE): study protocol for a randomized controlled trial.

    Trials·2017
    Same author

    Protective intraoperative ventilation with higher versus lower levels of positive end-expiratory pressure in obese patients (PROBESE): study protocol for a randomized controlled trial.

    Trials·2017

    Cardiac output measurements using an earpiece densitometer were less reliable than a standard flow-through method. Automatic computation led to overestimations, suggesting the earpiece is unsuitable for routine clinical use.

    Area of Science:

    • Cardiology
    • Medical Devices
    • Physiology

    Background:

    • Cardiac output (CO) determination is crucial for assessing cardiovascular function.
    • Dye dilution techniques are common methods for CO measurement.
    • Evaluating novel devices for CO assessment is essential for clinical practice.

    Purpose of the Study:

    • To compare the accuracy of a dichromatic earpiece densitometer with a standard flow-through densitometer for cardiac output determination.
    • To assess the reliability of automatic computation versus manual calculation using the earpiece device.
    • To determine the suitability of the earpiece densitometer for routine clinical use.

    Main Methods:

    • Cardiac output was measured in eleven subjects, including those with cardiopulmonary disease, using two methods: a dichromatic earpiece densitometer and an ordinary flow-through densitometer.

    Related Experiment Videos

  • The earpiece device was calibrated as a flow-through cuvette and allowed for automatic computation via a pressure capsule.
  • Measurements were compared using both automatic and manual calculations from the earpiece, against the flow-through densitometer results.

    • Main Results:

    • Automatic computation with the earpiece densitometer systematically overestimated cardiac output.
    • Manual calculation with the earpiece showed closer agreement to the flow-through cuvette but still exhibited deviations.
    • Residual standard deviations for single and double determinations were 0.8 l/min and 0.7 l/min, respectively.

    Conclusions:

    • The dichromatic earpiece densitometer, despite its ease of use, demonstrates significant unreliability for routine cardiac output measurements.
    • Automatic computation features of the earpiece device contribute to inaccuracies.
    • Further validation or improved technology is needed for earpiece densitometers to be considered clinically reliable.