Comparison of Two FiO2 (1 or 0.5) for Tracheal Extubation in Post-anesthesia Care Unit

Study Overview
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Brief Summary
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The purpose of the study is to assess the optimal fraction of inspired oxygen (0.5 or 1) for extubation or removal of a supraglottic airway device after general anesthesia.

Detailed Description
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During pre-anesthesia visit, eligible patients receive oral and written information of the study and potential risks. In the operating room all patients giving a written informed consent will undergo at the end of surgery a screening to determine eligibility for study entry. Before emergence from general anesthesia, patients who meet the eligibility requirements will be randomized in a open label manner to receive a 0.5 or 1 FiO2.

Official Title
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Comparison of Two FiO2 (1 or 0.5) for Tracheal Extubation in Post-anesthesia Care Unit : a Monocentric Randomized Trial

Conditions
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Anesthesia, Atelectasis, Postoperative Complications, Hypoxemia, Hyperoxia

Intervention / Treatment
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* Other: FiO2 0.5
* Other: FiO2 1


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing general anesthesia, with invasive mechanical ventilation including an airway device (supraglottic airway device or tracheal tube) at their arrival in PACU. ASA physical status classification 1, 2, or 3 stabilized. Surgery performed in emergency operating room department including vascular, digestive, urological and minor trauma surgery or surgery performed in head and neck anesthesia pole block including anterior cervical spine, lumbar disc herniation, cranioplasty, nerve stimulator, vertebroplasty, narrow lumbar canal, simple arthrodesis (less than or equal to two stages), otological, ophthalmological and skin surgery. Exclusion Criteria: Per-operative hemodynamic instability. Patients with a BMI greater than 35. Patients classified as difficult to intubate and / or ventilate. Heavy surgeries (operating time greater than 4 hours). Patient requiring postoperative non invasive mechanical ventilation Patients with diagnosed COPD SPO2 in room air < 96% before the intervention. Any patient under guardianship. Pre-operative and / or intra-operative morphine intake. Surgical management of the upper airways (ex : tonsillectomy) Pregnant and lactating women.

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 |
| --- | --- |
| Active Comparator: Control Group FiO2=1<br>FiO2 = 1 (100%) 10mn before emergence of general anesthesia | Other: FiO2 1<br>* Ten minutes before emergence from general anesthesia, the amount of oxygen delivered from the mechanical ventilator called fractional inspired oxygen (FiO2) is set to 1 (100%)<br>|
| Experimental: Intervention Group FiO2 0.5<br>Fi02 = 0.5 (50%) 10mn before emergence of general anesthesia | Other: FiO2 0.5<br>* Ten minutes before emergence from general anesthesia, the amount of oxygen delivered from the mechanical ventilator called fractional inspired oxygen (FiO2) is set to 0.5 (50%)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Decrease of oxygen saturation | Proportions of patients that present a decrease of 4 points of peripheral capillary oxygen saturation (SpO2) measured with pulse oximetry after extubation compared to their baseline room air SpO2 | Duration of stay in post-anesthesia care unit, approximately one hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Duration of emergence | Elapsed Time between cessation of sedation and extubation (minutes) | Up to one hour | 
| Primary Outcome Timing | Elapsed time between extubation and decrease of oxygen saturation (minutes) | Up to one hour | 
| Number of risk factors | Number of factors associated with episodes of hypoxemia : bronchospasm, bronchial congestion (profuse secretions with the need to aspirate the patient several times), loss of upper airway muscle tonus (fall of the tongue). | One hour | 
| Majored decrease of oxygen saturation | Proportions of patients that present a decrease of 6 points of SpO2 after extubation compared to their baseline room air SpO2 | One hour | 
| Corrective measures | Number of corrective measures (method and oxygen supply equipment used) after hypoxemia and proportion of success. | One hour | 
| PACU length of stay | Length of stay in post-anesthesia care unit | One hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Post-anesthesia care unit, Extubation