HFNC During Awake Craniotomy - Impact on Patient Comfort

Study Overview
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Brief Summary
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Background: Patients undergoing awake brain surgery are exposed to non-humidified, non-warmed oxygen/air mix flow through a face mask for a prolonged duration. This causes increased discomfort, inadequate breathing with the risk for hypoxia perioperatively. Humidified high flow nasal cannula (HFNC) oxygen therapy potentially improves patient comfort, oxygen/air exchange, improves surgical conditions and prevents atelectasis of the lung, compared to traditional oxygen administration using a face mask in patients undergoing awake brain surgery. Results of this trial will be used to initiate a more extensive, multicenter trial to further characterize the potential impact of HFNC.

Detailed Description
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Background: Patients undergoing awake brain surgery are exposed to non-humidified, non-warmed oxygen/air mix flow through a face mask for a prolonged duration. This causes increased discomfort, inadequate breathing with the risk for hypoxia perioperatively. Hypothesis: Humidified high flow nasal cannula (HFNC) oxygen therapy improves patient comfort, oxygen/air exchange, improves surgical conditions and prevents atelectasis of the lung, compared to traditional oxygen administration using a face mask in patients undergoing awake brain surgery. Methods: After obtaining ethics approval and written informed patient consent, 20 patients undergoing scheduled awake brain surgery will be randomized to either HFNC therapy or standard face mask. Evaluation of patient satisfaction, pain / dry upper airway along with drawing of arterial blood gases to measure oxygen/carbon dioxide content of the blood will be performed during and after the procedure. Lung ultrasound will be performed in the recovery room to determine the presence of atelectasis. Expected results and Significance: We expect that HFNC improves patient comfort as well as breathing / arterial oxygen content in long-duration awake brain surgery. This could result in higher patient satisfaction, shorter times in PACU, a shorter requirement for oxygen therapy, decreased risk for hypoxia during surgery and better elimination of carbon dioxide - which could lead to better surgical conditions due to softer brain tissue and therefore shorter time for the surgical procedure. Potential positive results of this trial will be used to initiate a more extensive, multicenter trial to further characterize the potential impact of HFNC.

Official Title
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Comparison of Pre-warmed, Humidified High Flow Nasal Cannula (HFNC) Oxygen Therapy and Traditional Oxygen Therapy on Patient Comfort and Gas Exchange During Awake Craniotomy - A Single Centre, Prospective, Randomized, Pilot Trial

Conditions
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Pulmonary Atelectasis, Patient Comfort

Intervention / Treatment
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* Device: HFNC
* Device: Oxygen Mask


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult patients undergoing elective awake craniotomy Exclusion Criteria: ASA > 4 pregnant females Body Mass Index (BMI) > 40 elective postoperative mechanical ventilation/conversion to general anesthesia denial of consent obstructive sleep apnea requiring CPAP severe COPD requiring home oxygen therapy

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: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: HFNC<br>HFNC will be started at flow of 40 L/min and FiO2 of 40%. | Device: HFNC<br>* High flow nasal humidified oxygen HFNC is an air-oxygen blender, which provides high flow (up to 60 L/min) of warmed (36°C) and humidified gas through nasal cannula, allowing tighter control of FiO2 from 0.2 to 1.0.<br>|
| Other: Oxygen Mask<br>Standard non-humidified oxygen therapy via an oxygen mask at 6 l/min will be performed. | Device: Oxygen Mask<br>* Application of oxygen during conscious sedation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient comfort using VAS (1-10) | Patient comfort during awake craniotomy | During surgical procedure, an average of 6 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gas exchange (blood gas analysis) |  | During surgical procedure (an average of 6 hours) and 15 minutes after PACU admission | 
| Post-operative pulmonary atelectasis using Ultrasound evaluation |  | Up to 15 minutes before PACU discharge | 
| Incidence of oxygen desaturation (number of events with SaO2 < 90%) |  | During surgical procedure, an average of 6 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Awake Craniotomy, HFNC, Oxygen Therapy, Atelectasis, Ultrasound, Patient Comfort