Positive Pressure and Gravity Affect Volumetric Capnography

The Effect of Positive Pressure and Body Position on Volumetric Capnography Assessed by Electrical Impedance Tomography

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT03853057

Enrollment

Registered

2019-02-25

Start date

2016-02-01

Completion date

2019-02-21

Last updated

2019-02-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Hypoventilation

Keywords

volumetric capnography, gravity, mechanical ventilation, EIT

Brief summary

Volumetric capnography is an interesting and non-invasive tool for monitoring ventilation in mechanically ventilated patients. The aim of this study was to test the effect of positive pressure ventilation and different body positions on volumetric capnograms.

Detailed description

In this interventional study awake and healthy volunteers will be submitted to spontaneous, pressure support and control pressure ventilation using a tight nasal mask. Volumetric capnography and electrical impedance tomography (EIT) will be continuously recorded during the protocol. Different body positions were randomly tested. Analysis of global and regional distribution of ventilation using EIT will be matched with changes observed in volumetric capnography-derived parameters.

Interventions

OTHERbody positions

positive pressure ventilation at different body positions

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

OTHER

Masking

NONE

Eligibility

Sex/Gender

MALE

Age

28 Years to 39 Years

Healthy volunteers

Yes

Inclusion criteria

* American Society Anesthesia physical status I. * Age between 25-39 years old, * Body mass index between 23-28 kg/m2, * Non-smokers.

Exclusion criteria

* Presence of pulmonary or cardiac diseases. * Abnormal spirometry.

Design outcomes

Primary

Measure	Time frame	Description
Analysis of the changes in volumetric capnographic parameters with changes in body positioning and positive pressure ventilation.	4 hours	The volunteers are breathing spontaneously with and without positive pressure support. Capnographic parameters were registered at each studied condition.

Secondary

Measure	Time frame	Description
Electrical impedance images of the distribution of ventilation with changes in body positioning and positive pressure ventilation.	4 hours	The volunteers are breathing spontaneously with and without positive pressure support. Electrical impedance images were taken at each studied condition.

Countries

Argentina

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026