Clinical trial NCT00922753: Inspiratory Support Improves Preoxygenation in Healthy Subjects
Official title: The Efficacy and Tolerability of Different Levels of Inspiratory Support and PEEP During Preoxygenation. A Randomized Controlled Trial.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: Preoxygenation
Inspiratory
Support
Healthy
EndtidalO2
Lead sponsor: Maisonneuve-Rosemont Hospital
Sponsor class: OTHER
First posted: 2009-06-17
Enrollment: 20
Sex: ALL
Minimum age (years): 20
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER

Brief summary: Preoxygenation optimizes oxygen content in the functional residual capacity (FRC). Adequate preoxygenation is defined by an expiratory oxygen fraction (FEO2) \> 90%. Inspiratory support and positive end expiratory pressure (PEEP) can create a better reservoir, improve gas exchange and shorten the time needed for adequate preoxygenation. The goal of the study is to evaluate the efficacy and tolerability of different levels of inspiratory support and positive end expiratory pressure during preoxygenation in healthy subjects.

Detailed description: We conducted a double blind prospective randomized trial on 20 healthy volunteers. Each subject went through three modes of preoxygenation in random order: normal breathing (SP), breathing under inspiratory support 4 cmH2O/PEEP 4 cmH2O (PSM-4) and inspiratory support 6 cmH2O /PEEP 4 cmH2O (PSM-6). Each mode lasted for 3 min and parameters were recorded every 10 s. We evaluated subject's tolerance, leaks and easiness of each mode of preoxygenation according to a simplified (1 to 4) scale. Two-way ANOVA was used to compare FEO2 while simple ANOVA was used for time to reach FEO2=90%.

Eligibility criteria: Inclusion Criteria:

* Healthy volunteers
* Aged between 20 to 40 years

Exclusion Criteria:

* Body mass index \> 30
* Mustache, beard
* Claustrophobia

Primary outcomes:
measure: expiratory oxygen fraction (end-tidal 02)
Secondary outcomes:
measure: inspiratory oxygen fraction
measure: end-tidal CO2
measure: tidal volume
measure: inspiratory pressure
measure: subject's tolerance
measure: leaks around the mask during preoxygenation
measure: minute volume
measure: endexpiratory pressure
Other outcomes:
Locations:
city: Montreal
country: Canada
facility: Maisonneuve Rosemont Hospital
state: Quebec
Study officials:
affiliation: Maisonneuve Rosemont Hospital, University Of Montreal
name: Issam Tanoubi, M.D.
role: PRINCIPAL_INVESTIGATOR
affiliation: Maisonneuve Rosemont Hospital, University Of Montreal
name: François Donati, PhD, MD, FRCPC
role: STUDY_DIRECTOR
affiliation: Maisonneuve Rosemont Hospital, University Of Montreal
name: Pierre Drolet, MD, FRCPC
role: STUDY_CHAIR
affiliation: Maisonneuve Rosemont Hospital, University Of Montreal
name: Louis Phillipe Fortier, MSc, MD, FRCPC
role: PRINCIPAL_INVESTIGATOR
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