Pre-oxygenation With Facemask Oxygen vs High-flow Nasal Oxygen vs High-flow Nasal Oxygen Plus Mouthpiece Oxygen (PREOX)

Pre-oxygenation With Facemask Oxygen vs High-flow Nasal Oxygen vs High-flow Nasal Oxygen Plus Mouthpiece Oxygen - a Randomised Controlled Trial

Pre-oxygenation increases oxygen reserves in the body to reduce the likelihood of oxygen desaturation on induction of general anaesthesia. Pre-oxygenation with facemask is the commonest method method of pre-oxygenation. High-flow nasal oxygen is a newer alternative. This study randomises participants to receive pre-oxygenation by one of three methods: facemask, high-flow nasal oxygen, high-flow nasal oxygen plus mouthpiece.

Study Overview

• Status: Completed
• Conditions: Apnea; Anesthesia; Respiration; Arrest
• Intervention / Treatment: Other: Pre-oxygenation

Detailed Description

The administration of supplemental oxygen prior to induction of anaesthesia is known as pre-oxygenation. Pre-oxygenation increases oxygen reserves in the body with the purpose of delaying the time until oxygen desaturation after breathing stops (apnoea) following the administration of an anaesthetic. In the last decade, clinicians have begun utilising high-flow nasal oxygen for pre-oxygenation. However, the rationale for this is based largely on its ability to achieve ongoing oxygenation after the onset of apnoea (apnoeic oxygenation). This study isolates oxygen administration with high-flow nasal oxygen to the period when the person is breathing, without ongoing oxygen administration during the apnoea period, to quantify its effects during the pre-oxygenation period only. A third group of participants breathes oxygen through a mouthpiece in addition to receiving oxygen via high-flow nasal cannulae. The effect of these pre-oxygenation methods will be measured by the time taken until oxygen saturation levels decline to the lower end of the normal range (92%), along with other parameters such as blood oxygen levels.

• Study Type: Interventional
• Enrollment (Actual): 84
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Ireland
  • Galway, Ireland
    • University Hospital Galway

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• 18 years of age or older
• ASA 1 or 2
• Receiving a general anaesthetic for non-emergent surgery

Exclusion Criteria:

• ASA score ≥3
• BMI ≥ 30 kg/m2
• Nasal obstruction
• Baseline SpO2 ≤95% on room air
• Anticipated difficult airway management
• Requirement for awake intubation
• Pregnancy
• Positive PCR test for coronavirus.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: NONE

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Facemask oxygen (FM); 100% oxygen administered via facemask through circle system with adjustable pressure-limiting valve at 0 cmH20. Participant instructed to 'breathe normally'	Other: Pre-oxygenation; Induction of anaesthesia after 2mins 45 seconds of pre-oxygenation with 1-1.5mcg/kg remifentanil plus 2-3mg/kg propofol. Propofol (10mg/kg/hr) and remifentanil (0.15mcg/kg/min) infusions commenced until study conclusion. Positive pressure ventilation commenced at Sp02 92%. Failure to intubate the patient during the first minute of apnoea results in withdrawal from the study. Blood samples obtained from an arterial catheter immediately prior to commencing pre-oxygenation, after 90 and 180 seconds of pre-oxygenation, after one minute of apnoea, and every two minutes during the apnoeic period.
ACTIVE_COMPARATOR: High-flow nasal oxygen (HFNO); 100% oxygen administered via high-flow nasal cannulae at 50 L/min. Participant instructed to 'keep the mouth closed and breathe normally'	Other: Pre-oxygenation; Induction of anaesthesia after 2mins 45 seconds of pre-oxygenation with 1-1.5mcg/kg remifentanil plus 2-3mg/kg propofol. Propofol (10mg/kg/hr) and remifentanil (0.15mcg/kg/min) infusions commenced until study conclusion. Positive pressure ventilation commenced at Sp02 92%. Failure to intubate the patient during the first minute of apnoea results in withdrawal from the study. Blood samples obtained from an arterial catheter immediately prior to commencing pre-oxygenation, after 90 and 180 seconds of pre-oxygenation, after one minute of apnoea, and every two minutes during the apnoeic period.
ACTIVE_COMPARATOR: High-flow nasal oxygen plus mouthpiece oxygen (HFNO+MP); 100% oxygen administered via high-flow nasal cannulae at 50 L/min. Additionally, 100% oxygen administered via mouthpice through circle system with adjustable pressure-limiting valve at 0 cmH20. Participant instructed to 'keep the mouth closed and breathe normally'.	Other: Pre-oxygenation; Induction of anaesthesia after 2mins 45 seconds of pre-oxygenation with 1-1.5mcg/kg remifentanil plus 2-3mg/kg propofol. Propofol (10mg/kg/hr) and remifentanil (0.15mcg/kg/min) infusions commenced until study conclusion. Positive pressure ventilation commenced at Sp02 92%. Failure to intubate the patient during the first minute of apnoea results in withdrawal from the study. Blood samples obtained from an arterial catheter immediately prior to commencing pre-oxygenation, after 90 and 180 seconds of pre-oxygenation, after one minute of apnoea, and every two minutes during the apnoeic period.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time to oxygen desaturation	The time period from the onset of apnoea (determined by visual inspection) until an oxygen saturation of 92% is measured by pulse oximetry.	Immediately after the intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Arterial partial pressure of oxygen after pre-oxygenation.	As measured by blood gas analysis	At 3 minutes of pre-oxygenation
Arterial partial pressure of carbon dioxide change during pre-oxygenation	As measured by blood gas analysis	At 0 and 3 minutes
Change in arterial partial pressure of carbon dioxide during apnoea	As measured by blood gas analysis	At 0, 1, 2 minutes and each 2 minutes thereafter
Change in acid-base status during apnoea	As measured by blood gas analysis	At 0, 1, 2 minutes and each 2 minutes thereafter
Correlation between end-tidal carbon dioxide measurement and arterial partial pressure of carbon dioxide	The EtCO2 value used for comparison is the highest value recorded during the first five respiratory cycles by manual ventilation with the adjustable pressure-limiting valve set at 20cmH20.	Etco2 obtained at the time of resumption of ventilation. Paco2 obtained from the preceding blood gas measurement.

Collaborators and Investigators

• Sponsor: University College Hospital Galway

Publications and helpful links

General Publications

• Lyons C, McElwain J, Coughlan MG, O'Gorman DA, Harte BH, Kinirons B, Laffey JG, Callaghan M. Pre-oxygenation with facemask oxygen vs high-flow nasal oxygen vs high-flow nasal oxygen plus mouthpiece: a randomised controlled trial. Anaesthesia. 2022 Jan;77(1):40-45. doi: 10.1111/anae.15556. Epub 2021 Aug 17.

Study record dates

Study Major Dates

• Study Start (ACTUAL): August 1, 2020
• Primary Completion (ACTUAL): January 13, 2021
• Study Completion (ACTUAL): January 13, 2021

Study Registration Dates

• First Submitted: January 31, 2021
• First Submitted That Met QC Criteria: February 22, 2021
• First Posted (ACTUAL): February 23, 2021

Study Record Updates

• Last Update Posted (ACTUAL): February 23, 2021
• Last Update Submitted That Met QC Criteria: February 22, 2021
• Last Verified: February 1, 2021

More Information

Terms related to this study

• Other Study ID Numbers: Preox-HFNO

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The sharing of anonymised patient-specific data that underlie results in any publication.
• IPD Sharing Time Frame: Post publication of results for up to fifteen years
• IPD Sharing Access Criteria: Investigator will consider requests to share patient-specific anonymised data in electronic format for the purpose of meta-analysis
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No