End-tidal oxygen achieved with preoxygenation via non-rebreather mask at different flow rates in healthy volunteers

Efficacy of preoxygenation via non-rebreather mask, comparing standard oxygen flow at 15lpm to maximally opened flow meter in healthy participants

Status

Completed

Phases

Phase 2

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12617000339358

Acronym

nil

Enrollment

Registered

2017-03-03

Start date

2016-03-01

Completion date

2016-05-31

Last updated

2017-05-22

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

Conditions

None listed

Brief summary

Preoxygenation is critical to safe emergency airway management. Outside of the operating theatre and in prehospital environments, ‘Over flow’ from a standard wall/cylinder outlet has been proposed to greatly enhance preoxygenation via a Non-rebreather mask (NRB). Methods We performed a randomised crossover trial using two preoxygenation conditions; a NRB at 15lpm and the other a NRB with the 15lpm flowmeter with the dial turned all the way open (over-flow). End-tidal oxygen (ETO2) as a measure of preoxygenation/denitrogenating efficacy, was measured by single exhaled vital capacity breath.

Interventions

The study design is two-period crossover study (repeated measures design) . Participants will complete two trials of 3-minutes pre-oxygenation via non-rebreather mask (NRM)., One trial will have an oxygen flow rate of 15lpm, The other will have the flow-meter valve turned wide open. The end-tidal oxygen (ETO2) will be measured at the end of each trial. The first trial will be followed by a washout period of 2 minutes. Allocation to the first trial (15lpm or fully open valve) will be randomised.

Study design

Allocation

Randomised controlled trial

Intervention model

Crossover

Primary purpose

Treatment

Masking

Open (masking not used)

Eligibility

Sex/Gender

All

Age

16 Years to 70 Years

Healthy volunteers

Yes

Inclusion criteria

No regular cardiovascular or respiratory medication, no history of chronic respiratory disease. Attendees at NSW Ambulance Aeromedical service governance days. We are not allowed to recruit outside of this site.

Exclusion criteria

Pregnancy, lung disease, known or suspected coronary or cerebrovascular disease, treatment for asthma or COPD, previous exposure to bleomycin, participants with beards, dentures or facial abnormalities affecting mask seal.

Outcome results