Oxygenation by 100% Oxygen Via High Flow Nasal Cannula in Surgical Patients

Study Overview
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Brief Summary
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Oxygenation with high-flow nasal cannula with 100% oxygen has only been evaluated in a limited number of studies. Although data are convincing it is of importance to evaluate this new concept in our department before implementing it into clinical practice. The general purpose of this project is to evaluate a new ventilation strategy during ENT-surgery based on oxygenation with high-flow nasal cannula with 100% oxygen with focus on gas exchange.

Official Title
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Evaluation of Oxygenation by 100% Oxygen Via High Flow Nasal Cannula During Apnea in Adult Elective Surgical ENT Patients

Conditions
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Anaesthesia, General, Anesthesia, Intravenous, Ventilation

Intervention / Treatment
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* Procedure: Hyperventilation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult, >18 years old ENT-surgery where apnea is of benefit for the surgeon (eg. intraoral or laryngeal surgery) and the anesthesia time is <40 mins. Capable of understanding the study information and sign the written consent. Exclusion Criteria: ASA>2 NYHA >2 BMI >30 Pregnancy Manifest cardiac failure or coronary disease Neuromuscular disease

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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Normoventilation<br>The patients will be normoventilated before anesthesia | |
| Experimental: Hyperventilation<br>Prior to anesthesia, the patients will hyperventilate during 2 mins or until symptoms from the central nervous system (e.g. dizziness). | Procedure: Hyperventilation<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in arterial carbon dioxide (pCO2) |  | From start of anaesthesia to end of apnoea oxygenation or max 30 minutes | 
| Change in arterial pH |  | From start of anaesthesia to end of apnoea oxygenation or max 30 minutes | 
| Change in arterial oxygen tension (pO2) |  | From start of anaesthesia to end of apnoea oxygenation or max 30 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Does hyperventilation prior to anaesthesia and apnoea oxygenation cause any difference in pCO2 in the end of the apnea (i.e. at up to 30 minutes) compared to normoventilation? |  | In the end of the apnoea period, i.e. at approximately 20 minutes | 
| Does hyperventilation prior to anaesthesia and apnoea oxygenation cause any difference in pH in the end of the apnea (i.e. at up to 30 minutes) compared to normoventilation? |  | In the end of the apnoea period, i.e. at approximately 20 minutes | 
| Does hyperventilation prior to anaesthesia and apnoea oxygenation cause any difference in pO2 in the end of the apnea (i.e. at up to 30 minutes) compared to normoventilation? |  | In the end of the apnoea period, i.e. at approximately 20 minutes | 
| Does the high oxygen content cause atelectasis measures as change in relation between pCO2 and end tidal carbon dioxide |  | Until discharge from the postoperative unit, often max 2 hours |