Evaluation of Different Methods for Preoxygenation

The goal of this randomised cross-over study is to compare pre-oxygenation using a standard nasal cannula to pre-oxygenation using humidified high-flow nasal oxygen and a tight-fitting facemask in adult volunteers with a BMI below 30 not suffering from pulmonary or cardiac comorbidity.

The main question it aims to answer is:

- Are there any differences in the effectiveness of pre-oxygenation using a standard nasal cannula compared to using a traditional facemask and pre-oxygenation using humidified high-flow nasal oxygen?

Participants will be pre-oxygenated with 100% oxygen during four minutes intervals. All participants will be pre-oxygenated with various flow rates using a standard nasal cannula, a facemask and humidified high-flow nasal oxygen. End-tidal oxygen concentrations will be measured continuously in order to evaluate the effectiveness of pre-oxygenation.

Each volunteer will be pre-oxygenated repeatedly, with different flow rates, with all three methods of pre-oxygenation and act as its own control.

During facemask pre-oxygenation volunteers will be pre-oxygenated using both tidal volume breathing for four minutes and with eight vital capacity breaths. During pre-oxygenation using the standard nasal cannula flow rates will vary between 15 and 50 l/min. Pre-oxygenation using humidified high-flow nasal oxygen will be performed with flow rates varying between 30 and 50 l/min. Series will be conducted with volunteers breathing with both opened and closed mouth as well as with four minutes of tidal volume breathing and eight vital capacity breaths.

All volunteers will start with facemask pre-oxygenation. They will thereafter be randomised to pre-oxygenation with either a standard nasal cannula or humidified high-flow nasal oxygen. Lastly, they will be pre-oxygenated with the remaining method according to the randomisation.

Study Overview

• Status: Completed
• Conditions: Anesthesia
• Intervention / Treatment: Device: Humidified high-flow nasal oxygen; Device: Standard nasal cannula; Device: Facemask

Detailed Description

Pre-oxygenation before anaesthesia induction is mostly performed using a tight-fitting facemask. Recently, studies have shown that pre-oxygenation using humidified high-flow nasal oxygen is equally effective as pre-oxygenation using a standard tight-fitting facemask. Pre-oxygenation using humidified high-flow nasal oxygen has several potential advantages including improved patient comfort and the possibility of a seamless transition from pre-oxygenation to apnoeic oxygenation. Unfortunately, this technique requires an additional machine which can be expensive and also difficult to use in settings outside a hospital.

In this study, pre-oxygenation using a standard nasal cannula delivering a high flow of oxygen will be compared with standard facemask pre-oxygenation and pre-oxygenation using humidified high-flow nasal oxygen in adult volunteers with a BMI below 30 not suffering from pulmonary or cardiac comorbidity.

The main question it aims to answer is:

- Are there any differences in the effectiveness of pre-oxygenation using a standard nasal cannula compared to using a traditional facemask and pre-oxygenation using humidified high-flow nasal oxygen?

Participants will be pre-oxygenated with 100% oxygen during four minutes intervals. All participants will be pre-oxygenated with various flow rates using a standard nasal cannula, a facemask and humidified high-flow nasal oxygen. End-tidal oxygen concentrations will be measured continuously in order to evaluate the effectiveness of pre-oxygenation.

Each volunteer will be pre-oxygenated repeatedly, with different flow rates, with all three methods of pre-oxygenation and act as its own control.

During facemask pre-oxygenation volunteers will be pre-oxygenated using both tidal volume breathing for four minutes and with eight vital capacity breaths. During pre-oxygenation using the standard nasal cannula flow rates will vary between 15 and 50 l/min. Pre-oxygenation using humidified high-flow nasal oxygen will be performed with flow rates varying between 30 and 50 l/min. Series will be conducted with volunteers breathing with both opened and closed mouth as well as with four minutes of tidal volume breathing and eight vital capacity breaths.

All volunteers will start with facemask pre-oxygenation. They will thereafter be randomised to pre-oxygenation with either a standard nasal cannula or humidified high-flow nasal oxygen. Lastly, they will be pre-oxygenated with the remaining method according to the randomisation.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Malin Jonsson Fagerlund, MD, PhD; Phone Number: +46707691405; Email: malin.jonsson.fagerlund@ki.se
• Study Contact Backup: Name: Albin Sjöblom, MD; Phone Number: +46704154346; Email: albin.sjoblom@ki.se

Study Locations

• Sweden
  • Stockholm, Sweden
    • Karolinska University Hospital, Solna
  • Stockholm, Sweden, SE-17176
    • Perioperative Medicine and Intensive Care Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Ability to understand and sign informed consent
• Age 25-65 years
• Body mass index <30

Exclusion Criteria:

• Heart disease
• Respiratory disease
• Pregnancy
• Smoker

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Humidified high-flow oxygen; Humidified high-flow nasal oxygen delivered via the Optiflow device. Repeated series with 100% oxygen with flows varying between 30 to 50 l/min. Volunteers will also be pre-oxygenated with both opened and closed mouth.	Device: Humidified high-flow nasal oxygen; Humidified high-flow oxygen delivered via the Optiflow device
Experimental: Standard nasal cannula; Standard nasal cannula connected to an oxygen rotameter Repeated series with 100% oxygen with flows varying between 15 to 50 l/min. Volunteers will also be pre-oxygenated with both opened and closed mouth.	Device: Standard nasal cannula; Oxygen delivered with high flows via a standard nasal cannula
Active Comparator: Facemask; Tight-fitting facemask. Two series will be done where pre-oxygenation will be performed with four minutes of tidal volume breathing and eight vital capacity breaths. This arm is not randomised. All study subjects will start with facemask pre-oxygenation and are thereafter randomised to standard nasal cannula or humidified high-flow nasal cannula.	Device: Facemask; Oxygen delivered with facemask

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Comparison of the effectiveness of pre-oxygenation	Compare end-tidal oxygen levels after three minutes of pre-oxygenation using a standard facemask, high-flow nasal oxygen and a standard nasal cannula.	After 3 minutes of preoxygenation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Duration of pre-oxygenation until end-tidal oxygen levels above 80%	Evaluation of end-tidal oxygen levels will be done each minute during all series of pre-oxygenation in order to investigate the time taken until reaching end-tidal levels above 80%. A comparison between the time taken to achieve end-tidal levels above 80% will be done between the different methods of pre-oxygenation as well as the different flow rates.	After 3 minutes of preoxygenation
Duration of pre-oxygenation until end-tidal oxygen levels above 85%	Evaluation of end-tidal oxygen levels will be done each minute during all series of pre-oxygenation in order to investigate the time taken until reaching end-tidal levels above 85%. A comparison between the time taken to achieve end-tidal levels above 80% will be done between the different methods of pre-oxygenation as well as the different flow rates.	After 3 minutes of preoxygenation
Continuous comparison of end-tidal oxygen levels	Evaluation of end-tidal oxygen levels will be done after one, two, three and four minutes of pre-oxygenation. Comparison between the different methods and flow rates of pre-oxygenation will be done in order to evaluate which method and flow rate generates adequate end-tidal oxygen levels most quickly.	After 3 minutes of preoxygenation
Pre-oxygenation with open and closed mouth	All volunteers will be pre-oxygenated with both open and closed mouths in order to evaluate if there are any differences in end-tidal oxygen levels when breathing with open or closed mouth.	After 3 minutes of preoxygenation
Vital capacity breathing vs tidal volume breathing	End-tidal oxygen levels during pre-oxygenation will be evaluated and compared between tidal volume breathing for three minutes and eight vital capacity breaths.	After 3 minutes of preoxygenation
Differences in end-tidal oxygen levels after pre-oxygenation due to age, body mass index or sex.	Subgroup analysis will be performed in order to investigate any differences in the effect of pre-oxygenation depending on volunteer age, body mass index or sex.	After 3 minutes of preoxygenation
Discomfort	Level of discomfort, on a scale between one and ten, where ten is the worst discomfort and 0 is the best comfort) will be compared between the three different methods of pre-oxygenation and the different flow rates.	After 3 minutes of preoxygenation

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety outcome	Do more volunteers report problem with headache or nosebleed during pre-oxygenation with the standard nasal cannula compared to pre-oxygenation with facemask or humidified high-flow nasal oxygen?	After 3 minutes of preoxygenation

Collaborators and Investigators

• Sponsor: Malin Jonsson Fagerlund
• Collaborators: Karolinska Institutet
• Investigators: Principal Investigator: Malin Jonsson Fagerlund, Karolinska University Hospital and Karolinska Institutet

Study record dates

Study Major Dates

• Study Start (Actual): May 2, 2023
• Primary Completion (Actual): May 31, 2023
• Study Completion (Actual): May 31, 2023

Study Registration Dates

• First Submitted: April 20, 2023
• First Submitted That Met QC Criteria: April 20, 2023
• First Posted (Actual): May 3, 2023

Study Record Updates

• Last Update Posted (Actual): August 8, 2023
• Last Update Submitted That Met QC Criteria: August 7, 2023
• Last Verified: August 1, 2023

More Information

Terms related to this study

• Keywords: Oxygenation; Preoxygenation; High-flow nasal oxygen; Low-flow nasal oxygen
• Other Study ID Numbers: PreFlow

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No