The Role of High-flow Nasal Cannula Therapy in the Treatment of Acute Carbon Monoxide Poisoning

Study Overview
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Brief Summary
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The aim of the study is to test whether oxygen therapy delivered through high-flow nasal cannula devices in patients admitted to the emergency department for acute carbon monoxide poisoning is superior to the non-rebreathing oxygen face mask therapy with a 15 L/minute oxygen flow (currently the first-line therapy), in terms of reduction of carboxyhemoglobin (COHb) concentration and delayed neurological sequelae incidence.

Official Title
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High-flow Nasal Cannula Therapy in the Treatment of Acute Carbon Monoxide Poisoning

Conditions
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Carbon Monoxide Poisoning

Intervention / Treatment
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* Device: High-flow nasal cannula device
* Device: Non-rebreathing oxygen mask group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age v 18 years Carbon monoxide intoxication as major problem leading to emergency department admission Carboxyhemoglobin (COHb) concentration 10% at the time of enrolment Exclusion Criteria: Age < 18 years Glasgow coma scale ≤ 13 Refusal to give consent

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomised controlled trial
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: High-flow nasal cannula group<br>Patients randomised in this group will receive oxygen therapy via a high-flow nasal cannula device with a 60 L/min flow and a 100% fraction of inspired oxygen | Device: High-flow nasal cannula device<br>* Patients will be randomly allocated to this treatment<br>* Other names: AIRVO 2, Fisher & Paykel Healthcare LTD;|
| Other: Non-rebreathing oxygen mask group<br>In this group patients will be treated with standard oxygen therapy delivered through a non-rebreathing face mask with a 15 L/min flow | Device: Non-rebreathing oxygen mask group<br>* Patients will be randomly allocated to this treatment<br>* Other names: Standard non-rebreathing oxygen mask;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| COHb reduction at 90 minutes | Patients in the High-flow nasal cannula group and patients in the non-rebreathing oxygen mask group will be compared in terms of COHb reduction at 90 minutes. The hypothesis is that in patients treated with high flow nasal cannula the reduction in COHb at 90 minutes will be significantly different compared to patients treated with non-rebreathing oxygen mask. | 90 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Variation in the incidence of delayed neurologic sequelae | Patients in the High-flow nasal cannula group and patients in the non-rebreathing oxygen mask group will be compared in terms of incidence and severity of delayed neurologic syndrome. At the time of discharge from the emergency department, each enrolled patient will undergo neurocognitive testing. Six weeks after discharge, a follow-up visit for each patient will be performed which will include neurocognitive testing and a functional magnetic resonance imaging, in order to determine the presence of delayed neurologic sequelae. Patients in the two groups of treatment will be subsequently compared. | 6 weeks | 
| Variation in serum lactate concentration | Patients in the High-flow nasal cannula group and patients in the non-rebreathing oxygen mask group will be compared in terms of serum lactate variations. In particular, serum lactate levels will be evaluated at different time points, in order to test whether different treatments lead to different kinetic. | 6 weeks | 
| Variation in serum troponin concentration | Patients in the High-flow nasal cannula group and patients in the non-rebreathing oxygen mask group will be compared in terms of troponin concentration variations. In particular, serum troponin levels will be evaluated at different time points, in order to test whether different treatments lead to different kinetic. | 6 weeks | 
| Variation in S100B levels concentration | Patients in the High-flow nasal cannula group and patients in the non-rebreathing oxygen mask group will be compared in terms of serum protein S100B variations. In particular, protein S100B will be evaluated at different time points, in order to test whether different treatments lead to different protein kinetic. | 6 weeks |