Effectiveness of Preoxygenation With Positive Airway Pressure: a Comparison of the Supine and 25° Head up Position

Effectiveness of Preoxygenation With Positive Airway Pressure in Non-obese Healthy Patient: a Comparison of the Supine and 25° Head up Position

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT03861949

Enrollment

Registered

2019-03-05

Start date

2014-06-15

Completion date

2015-06-15

Last updated

2019-03-06

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

Conditions

Intubation;Difficult

Keywords

apnea, CPAP, Preoxygenation

Brief summary

Several techniques such as positive airway pressure and head-up tilt during preoxygenation have shown to prolong non-hypoxic apnea period compared to conventional technique. However, uniform recommendations have not yet been made. Therefore, in the present study the investigators attempted to find out the effect of combination of 5 cmH2O CPAP and 25° head up position during preoxygenation.

Detailed description

In this study 60 non-obese healthy adult patients were divided into three groups; Group C receiving preoxygenation in conventional technique, Group S receiving preoxygenation with 5 cmH2O CPAP and Group H receiving preoxygenation in 25° head-up position with 5 cmH2O CPAP. After 3 min of preoxygenation, anesthesia was induced and trachea intubated. After confirming the tracheal intubation by direct visualization, all patients were left apneic in supine position with the tracheal tube exposed to atmosphere till the SpO2 dropped to 92%. The primary outcome compared between the groups was the non-hypoxic apnoeic period (time to fall SpO2 to 92%).

Interventions

OTHER5 cmH2O CPAP

OTHERhead-up position

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

PREVENTION

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to 60 Years

Healthy volunteers

Yes

Inclusion criteria

* adult patients of ASA physical status I and II undergoing surgery under general anaesthesia

Exclusion criteria

* anticipated difficult mask ventilation/ intubation * individuals with significant cardiorespiratory or cerebrovascular disease * pregnant ladies * patient with history of epilepsy * body mass index \>25 kg/m2 * hemoglobin \<8 gm/dL * patients who were non-ambulant for \>24 h, having SpO2 \< 97% while breathing in room air * phobia to facemask.

Design outcomes

Primary

Measure	Time frame	Description
non-hypoxic apnoeic period (time to fall SpO2 to 92%)	2 hours	After 3 min of preoxygenation, anesthesia was induced and trachea intubated. After confirming the tracheal intubation by direct visualization, all patients were left apneic in supine position with the tracheal tube exposed to atmosphere till the SpO2 dropped to 92%.

Secondary

Measure	Time frame	Description
Comparison of pH at different time points	2 hours	Arterial blood gas analysis was done and the pH at the start of preoxygenation, after preoxygenation and at desaturation (SpO2= 92%) were compared.
Comparison of PaO2 at different time points	2 hours	Arterial blood gas analysis was done and the PaO2 at the start of preoxygenation, after preoxygenation and at desaturation (SpO2= 92%) were compared.
Comparison of PaCO2 at different time points	2 hours	Arterial blood gas analysis was done and the PaCO2 at the start of preoxygenation, after preoxygenation and at desaturation (SpO2= 92%) were compared.

Outcome results

None listed

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