EPO2-PV: Evaluation of Pre-Oxygenation Conditions in Morbidly Obese Volunteer: Effect of Position and Ventilation Mode (EPO2-PV)

September 14, 2017 updated by: Jean Bussières, Laval University

Evaluation of Different Pre-Oxygenation Conditions in Morbid Obesity: Position and Ventilation Mode, in a Respiratory Physiology Laboratory, on Voluntary Subjects

The risk of complications associated with airway management in obese patients is significant. The results of pre-oxygenation allow a prolonged non-hypoxic apnea time for the clinician. The increase in FRC and non-hypoxic apnea time is correlated. The best condition to accomplish the pre-oxygenation in morbidly obese patient is still undetermined in medical literature.

This study is designed to evaluate the effect of different positions combined with different ventilation modes during the pre-oxygenation phase of anesthesia's induction. EPO2: PV will evaluate the effect of different combinations of positions and ventilation modes on pulmonary volumes (mainly functional residual capacity) in a morbidly obese volunteer.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Complications related to airway management are the major contributing factor to morbidity in anesthesiology. This risk of complications markedly increases when faced with a difficult airway in an obese patient. Pre-oxygenation creates a safety margin by increasing the patient's oxygen stores, through a higher functional residual capacity (FRC). When pre-oxygenated, the clinician may proceed to intubation after a variable period of apnea, while maintaining oxygen saturation over 92%. In non-obese individuals, pre-oxygenation allows a non-hypoxic apnea time of eight minutes. In the obese population, however, this non-hypoxic apnea time decreases to two to three minutes.

Different methods of pre-oxygenation have been proposed in order to increase apnea time before significant oxygen desaturation. Amongst these methods, the following are of particular interest: pre-oxygenation to vital capacity, pre-oxygenation with spontaneous ventilation and positive pressure, and pre-oxygenation with elevated head positioning ("beach-chair"). These methods have been extensively studied in individuals of normal height and weight.

The main objective of pre-oxygenation is to raise oxygen levels available at the alveolar level in order to increase the non-hypoxic apnea time, before a significant desaturation occurs. This raised alveolar oxygen concentration can be done by maintaining a higher inspired oxygen fraction and by promoting a larger FRC which is the oxygen reserve build through the pre-oxygenation phase. In morbid obese patients, these parameters are affected by a lower expiratory flow, lower expiratory flow and closing of small radius airways. The final result probably come from a more cephalad position of the diaphragm induced by a larger intra-abdominal volume.

Actually, different studies demonstrate the advantage of a beach-chair position and non-invasive positive pressure ventilation for pre-oxygenation of obese patients. These advantages are shown by a shorter time of pre-oxygenation to obtain an end-tidal O2 > 90 % and a longer non-hypoxic apnea time (Sat O2 >90%). Up to date, there is no published data on the FRC as a result of different combinations of position and ventilation mode. This study will evaluate FRC by helium dilution technique.

We propose a crossover randomised trial on volunteers waiting for a bariatric surgery. We want to compare, in pre-oxygenation situation, without induction of general anesthesia, the effect of three positions and two ventilation modes on the FRC measure.

Study Type

Interventional

Enrollment (Actual)

20

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Canada
    • Quebec
      • Quebec city, Quebec, Canada, G1V4G5
        • Institut universitaire de Cardiologie et de Pneumologie de Quebec

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

21 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • BMI 40 - 80 kg / m2
  • Waist circumference: Men: More than 130 cm
  • Waist circumference: Women: More than 115 cm

Exclusion Criteria:

  • Facial hair
  • Cranio-facial abnormality
  • Claustrophobia
  • Asthma
  • COPD (defined by FEV1 < 80 %)
  • Severe cardiovascular disease (defined by NYHA ≥3)
  • Pregnancy
  • Tobacco use
  • NI-CPPV Intolerance documented by a respiratory specialist (pneumologist).

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Supine
NIPPV and Tidal volume
Procedure: NIPPV

Ventilation: non-invasive positive pressure ventilation (NIPPV)

Positive end-expiratory pressure: 10 cmH20 Pressure support: 5 - 20 cm H2O for tidal volume of 10 mL / kg (ideal body weight)

Procedure: Tidal volume
Tidal volume spontaneous ventilation, no assistance.
Experimental: Beach-chair (Back : 25 deg)
NIPPV and Tidal volume
Procedure: NIPPV

Ventilation: non-invasive positive pressure ventilation (NIPPV)

Positive end-expiratory pressure: 10 cmH20 Pressure support: 5 - 20 cm H2O for tidal volume of 10 mL / kg (ideal body weight)

Procedure: Tidal volume
Tidal volume spontaneous ventilation, no assistance.
Experimental: Proclive (Global 25 deg)
NIPPV and Tidal volume
Procedure: NIPPV

Ventilation: non-invasive positive pressure ventilation (NIPPV)

Positive end-expiratory pressure: 10 cmH20 Pressure support: 5 - 20 cm H2O for tidal volume of 10 mL / kg (ideal body weight)

Procedure: Tidal volume
Tidal volume spontaneous ventilation, no assistance.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Functional Residual Capacity
Time Frame: After a 5 minutes pre-oxygenation period
Change of functional residual capacity (FRC), in obese patient, as a result of different pre-oxygenation positions; 1- supine, 2-beach-chair, 3- reverse Trendelenburg, in two different ventilation modes : 1- spontaneous ventilation at tidal volume, 2- non-invasive positive pressure ventilation with inspiratory assistance.
After a 5 minutes pre-oxygenation period

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Diaphragmatic Amplitude.
Time Frame: After a 5 minutes pre-oxygenation period
Evaluation of changes in diaphragmatic amplitude and movement determined by fluoroscopy imaging after a 5 minutes pre-oxygenation period in the 6 combinations previously described.
After a 5 minutes pre-oxygenation period
Respiratory Mechanics
Time Frame: At the end of a 5 minutes pre-oxygenation period
Change in respiratory mechanics (compliance, resistance, tidal volume, positive end-expiratory pressure, maximal inspiratory pressure) evaluated at the end of a 5 minutes pre-oxygenation period in the 6 combinations previously described.
At the end of a 5 minutes pre-oxygenation period
Patient's Comfort
Time Frame: At the end of a 5 minutes pre-oxygenation period
Evaluation of the patient's comfort at the end of each intervention on an analog visual scale after a 5 minutes pre-oxygenation period in the 6 combinations previously described.
At the end of a 5 minutes pre-oxygenation period

Other Outcome Measures

Outcome Measure
Measure Description
Time Frame
Vital Signs
Time Frame: At the end of a 5 minutes pre-oxygenation period
Change in vital signs before and after the pre-oxygenation phase in the 6 combinations after a 5 minutes pre-oxygenation period in the 6 combinations previously described.
At the end of a 5 minutes pre-oxygenation period

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Laval University

Investigators

  • Principal Investigator: Etienne J Couture, MD, Laval University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

April 1, 2014

Primary Completion (Actual)

June 1, 2014

Study Completion (Actual)

July 1, 2014

Study Registration Dates

First Submitted

April 22, 2014

First Submitted That Met QC Criteria

April 23, 2014

First Posted (Estimate)

April 24, 2014

Study Record Updates

Last Update Posted (Actual)

April 9, 2018

Last Update Submitted That Met QC Criteria

September 14, 2017

Last Verified

September 1, 2017

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • IUCPQ 21054

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Morbid Obesity

Clinical Trials on NIPPV

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Papua New Guinea

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe