Comparison of Three Pre-oxygenation Strategies

Institute of Mountain Emergency Medicine

Status: Enrolling

Conditions: Emergencies; Anesthesia

Treatments: Other: Preoxygenation

Study type: Interventional

Funder types: Other

Identifiers

NCT06370689

PRE-OX

Details and patient eligibility

About

Study objective: Comparing the efficacy of three different preoxygenation strategies, i.e. non-rebreather face mask (NRM), bag-valve-mask (BVM) with and BVM without additional positive end-expiratory pressure (PEEP) in three subgroups of spontaneously breathing volunteers.

Study endpoints

Primary Endpoint:

Difference in expiratory oxygen concentration (FeO2) at the end of the 3 min preoxygenation sessions.

Secondary endpoints:

• Difference in Oxygen Reserve Index (ORi) at the end of the 3 min preoxygenation sessions.
• Changes in regional ventilation from baseline to 1.5 min and 3 min into the preoxygenation sessions, assessed using electrical impedance tomography (EIT)
• Time to reaching an Oxygen Reserve Index (ORi) ≥ 0.5
• Time to reaching an Oxygen Reserve Index (ORi) =1
• Time to Oxygen Reserve Index (ORi) back to baseline after the 3 min preoxygenation sessions.

Number of participants 15 participants per subgroup, i.e. 45 participants in total.

Inclusion criteria

• Normal-weight adults (body mass index, BMI 18.5-24.9 kg/m2) with an "American Society of Anesthesiologists Physical Status Classification System (ASA) " score of I or II
• Adults with a BMI 25-39.9 kg/m2 with and ASA score <3
• Healthy (ASA I) children aged 6-12 years Exclusion criteria ASA 3, Age < 6 and age 12-18, pregnant women, missing informed consent, signs and symptoms of an acute respiratory illness on the study day.

After informed consent and a medical check-up, baseline measurements will be done for 10 minutes (peripheral oxygen saturation SpO2, ORI, regional ventilation). Then the participants will undergo 3 different preoxygenation sessions with the 3 interfaces (i.e. non-rebreather facemask with reservoir and a bag-valve-mask with and without PEEP) in a randomized order and a 20 min washout between the sessions. Each preoxygenation session is conducted in a supine position and will be proceeded until the measured FeO2 (end expiratory O2 fraction) reaches 90% or up to a maximum time of 3 min. Afterwards 10 min of SpO2, ORI and regional ventilation measurements will follow.

Enrollment: 45 estimated patients

Sex: All

Ages: 6+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Normal-weight adults (BMI 18.5-24.9 kg/m2) with an "American Society of Anesthesiologists Physical Status Classification System (ASA) " score of I or II
• Adults with a BMI 25-39.9 kg/m2 with and ASA score <3
• Healthy (ASA I) children aged 6-12 years

Exclusion criteria

• ASA 3
• Age < 6 and age 12-18
• pregnant women
• missing informed consent
• signs and symptoms of an acute respiratory illness on the study day

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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45 participants in 9 patient groups

NRM - Non-rebreather mask in children 6-12 yrs

Active Comparator group

Description:

Non-rebreather mask in children 6-12 yrs

Treatment:

Other: Preoxygenation

BVM with PEEP in children 6-12 yrs

Active Comparator group

Description:

Bag valve mask with positive end-expiratory pressure (PEEP) in children 6-12 yrs

Treatment:

Other: Preoxygenation

BVM without PEEP in children 6-12 yrs

Active Comparator group

Description:

Bag valve mask without positive end-expiratory pressure (PEEP) in children 6-12 yrs

Treatment:

Other: Preoxygenation

NRM - Non-rebreather mask in normal weight adults

Active Comparator group

Description:

Non-rebreather mask in normal weight adults

Treatment:

Other: Preoxygenation

BVM with PEEP in normal weight adults

Active Comparator group

Description:

Bag valve mask with positive end-expiratory pressure (PEEP) in normal weight adults

Treatment:

Other: Preoxygenation

BVM without PEEP in normal weight adults

Active Comparator group

Description:

Bag valve mask without positive end-expiratory pressure (PEEP) in normal weight adults

Treatment:

Other: Preoxygenation

NRM - Non-rebreather mask in overweight/obese adults

Active Comparator group

Description:

Non-rebreather mask in overweight/obese adults

Treatment:

Other: Preoxygenation

BVM with PEEP in overweight/obese adults

Active Comparator group

Description:

Bag valve mask with positive end-expiratory pressure (PEEP) in overweight/obese adults

Treatment:

Other: Preoxygenation

BVM without PEEP in overweight/obese adults

Active Comparator group

Description:

Bag valve mask without positive end-expiratory pressure (PEEP) in overweight/obese adults

Treatment:

Other: Preoxygenation