Can we Improve Preoxygenation by Using Adjustable Pressure Limiting Valve (APL) ?

The Effects of Setting Adjustable Pressure Limiting Valve (APL) to 5 cmH2O on Preoxygenation

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT04010279

Enrollment

Registered

2019-07-08

Start date

2019-07-09

Completion date

2019-07-16

Last updated

2019-11-13

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

Conditions

Preoxygenation

Keywords

preoxygenation, CPAP(continuous positive airway pressure), APL (airway pressure release) valve

Brief summary

The aim of this study is to investigate the effects of setting airway pressure release valve (APL valve) on the anesthesia workstation to 5 cmH2O during spontaneous breathing on preoxygenation. In this prospective study healthy volunteers are randomized in cross-over between spontaneous breathing with the APL valve on spontaneous position or spontaneous breathing with the APL valve on 5 cmH2O or CPAP (continous positive airway pressure) mode with 5 cmH2O PEEP (positive end expiratory pressure).

Detailed description

There are several methods to improve preoxygenation but most of them require advanced anesthesia workstations. Therefore the investigators planned an an experimental study on healthy volunteers to investigate the effects of a simple method on preoxygenation. Healthy volunteers are randomized in cross-over between spontaneous breathing with the APL valve on spontaneous position or spontaneous breathing with the APL valve on 5 cmH2O or CPAP mode with 5 cmH2O PEEP. The volunteers will breath through an anesthesia face mask. The fresh gas flow rate is 12 L/min, inspiratory fraction of oxygen is 100%. The exhaled gas (oxygen and carbon dioxide) are monitored. The inspiratory and end expiratory fraction of oxygen will be recorded every 10 seconds. The primary endpoint is the time to achieve end expiratory fraction of oxygen of 90% or more.The secondary endpoint is the proportion of subject with end expiratory fraction of oxygen of 90% or more after a 3 min period and the end expiratory fraction of oxygen at the third minute.

Interventions

PROCEDUREpreoxygenation with 100% O2, fresh gas flow rate 12 L/minute

volunteers will be placed in supine position, fresh gas flow rate will be set at 12 L/min and delivered oxygen concentration will be set at 100%.

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

PREVENTION

Masking

DOUBLE (Subject, Outcomes Assessor)

Eligibility

Sex/Gender

ALL

Age

18 Years to 40 Years

Healthy volunteers

Yes

Inclusion criteria

* healthy volunteers

Exclusion criteria

* any respiratory disease

Design outcomes

Primary

Measure	Time frame
time to reach end expiratory fraction of oxygen of 90% or more	5 minutes

Secondary

Measure	Time frame	Description
proportion of volunteer with end expiratory fraction of oxygen of 90% or more after a 3 min period	3 minutes	—
End expiratory oxygen fraction at the 3th minute	3 minutes	—
Verbal rating Score	5 minutes	After completion of the whole arms of the study the volunteers will give a score between 0-10 to define the difficulty of breathing during the procedure

Countries

Turkey (Türkiye)

Outcome results

None listed

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