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Completed

NCT Number: NCT05302219

Plethysmography Curve Variability Depending on the Breath Cycle

The aim of the study is to analyze the variability of plethysmography curve depending on the breath cycle (respiratory rate and tidal volume).

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Key information

Conditions

Apnea Circulatory; Change Pathologic Processes Pathological Conditions, Signs and Symptoms Respiration Respiration Disorders Respiratory Aspiration Respiratory Tract Diseases Signs and Symptoms Signs and Symptoms, Respiratory

Age range

18 year–30 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Faculty of Biomedical Engineering, Czech Technical University in Prague

Kladno, 27201, Czechia

About this study

The plethysmography curve measured by finger sensors using pulse oximetry shows the changes in blood volume at the measured site. The presence of respiratory information within the pulse oximeter signal is a well-documented phenomenon. However, previous studies have mainly focused on extracting the respiratory rate from the plethysmography curve. The aim of this study is to analyze the variability of plethysmography curve as a function of both respiratory rate and tidal volume. Furthermore, the aim is to analyze the possibilities of apneic pause detection from the plethysmography curve.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • healthy volunteers/students from the Czech Technical University in Prague

Exclusion criteria

  • any acute illness
  • pregnancy
  • severe cardiovascular conditions
  • severe asthma or other severe respiratory conditions
  • diabetes
  • hypotension or hypertension

Treatment and study plan

Respiratory Rate

Other

The participant alternates respiratory rates of 30, 15 and 7.5 breaths/min. Breathe each frequency for 2 minutes with a one-minute break.

Tidal volume

Other

The participant alternates tidal volumes of approx. 2, 1 and 0.5 litres. Breathe each tidal volume for 2 minutes with a one-minute break.

Apnea

Other

The participant simulates three apneic pauses lasting 1 minute with a two-minute break.

Primary outcomes

  1. Variability of plethysmography curve depending on the respiratory rate

    Time frame: 1 hour

    The effect of different respiratory rates (including apnea-zero respiratory rate) on the shape of the plethysmography curve will be evaluated.

  2. Variability of plethysmography curve depending on the tidal volume

    Time frame: 1 hour

    The effect of different tidal volumes (including apnea-zero tidal volume) on the shape of the plethysmography curve will be evaluated.

Sponsors and collaborators

Lead sponsor

Czech Technical University in Prague

Other

Registry information

Important dates

Study start
2022
Primary completion
2022
Study completion
2022
First posted
Mar 31, 2022
Registry last updated
Mar 25, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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