Preoxygenation With a High-flow Nasal Cannula or a Simple Mask Before General Anesthesia in Head and Neck Surgery

Study Overview
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Brief Summary
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Objectives: To assess arterial oxygen partial pressure (PaO2) at defined time points during the preoxygenation and to compare between high ﬂow heated humidified nasal oxygen versus standard preoxygenation with oxygen insufflation via face mask over at least 5 minutes Methods: This randomized, single-blinded, prospective study was conducted at Asan Medical Center in Seoul, Republic of Korea. Populations: Patients undergoing head and neck surgery Expected outcomes: The course of PaO2 levels is superior to those of the face mask during the whole preoxygenation procedure and after the intubation.

Detailed Description
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Rationale & background information: Pre-oxygenation before general anesthesia is usually achieved using oxygen delivered via a facemask before induction of anesthesia; this potentially extends the time available for securing the airway before hypoxemia to 6 min. The lungs are commonly ventilated with a bag/facemask technique after induction, and this can be repeated if attempts at intubating the trachea are prolonged. However, facemask ventilation has traditionally been avoided in the circumstance which has the risk of gastric insufflation of gas, leading to increased intragastric pressure and raised risk of pulmonary aspiration of stomach contents. In addition, if difficult ventilation is anticipated, facemask ventilation may not be possible at all, and 6 minutes with hypoxemia may be insufficient for intubation. An ideal preoxygenation to extend apnea tolerance during anesthesia induction is essential to avoid live threatening airway incidents. The high-flow nasal cannula, the OptiFlow System (Thrive, Fisher & Paykel®, Aukland New Zealand), has the ability to deliver warmed and humidified oxygen through specially designed nasal cannula and enable oxygen to be comfortably delivered at rates of > 70 liter/min. Several study showed that nasal delivery of humidified oxygen to paralyzed and anesthetized patients at these rates maintains oxygenation and achieves acceptable carbon dioxide concentration. The investigators hypothesized that an extended apneic period without facemask ventilation could be particularly beneficial to patients undergoing general anaesthesia. Study goals and objectives: To assess arterial oxygen partial pressure (PaO2) at defined time points during the preoxygenation and to compare between high ﬂow heated humidified nasal oxygen versus standard preoxygenation with oxygen insufflation via face mask over at least 5 minutes

Official Title
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Comparison of Preoxygenation With a High-flow Nasal Cannula and a Simple Mask Before Intubation During Induction of General Anesthesia in Patients Undergoing Head and Neck Surgery

Conditions
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Head and Neck Neoplasm

Intervention / Treatment
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* Device: High-flow nasal cannula
* Device: simple mask


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with head and neck cancer undergoing resection surgery planned arterial cannulation and invasive arterial blood pressure monitoring and arterial blood gas analysis Patients over 19-year old Patients who voluntarily participated in the study Patents in American Society of Anesthesia physical status 1-3 Exclusion Criteria: Patients who don't approve to participation Unable to give informed consent because of a language barrier Patients with severe respiratory disease Patients with severe cardiovascular or cerebrovascular disease Patients with severe psychiatric disorders Anyone who is not appropriate according to researcher's decision

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 80 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 |
| --- | --- |
| Experimental: Group N<br>pre-oxygenation with High-flow nasal cannula | Device: High-flow nasal cannula<br>* Apply high ﬂow heated (34 °C) and humidified nasal oxygen with the OptiFlow System (Thrive, Fisher & Paykel®, Aukland New Zealand) using a ﬂow of 30 liter/minute and an inspiratory oxygen fraction (FiO2) of 1.0. Increase the oxygen flow to 60 liter/minute over the course of the first minute. Ask the patients not to speak during anesthesia induction and keep the mouth closed.<br>|
| Active Comparator: Group M<br>pre-oxygenation with simple mask | Device: simple mask<br>* Perform standard preoxygenation by oxygen insufflation via a face mask using the standard anesthesia ventilators (semicircular system) with 100% oxygen ﬂow of 12 liter/minute. The patients breathe with tidal volume.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PaO2 (arterial oxygen partial pressure) at pre-defined time points. | changes of PaO2 | through study completion, an average of 10 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| degree of blood oxygenation oxygenation | result of arterial blood gas analysis | through study completion, an average of 10 minutes | 
| various patients' characteristics about airway | upper lip bite test classification (class 1 3) | through study completion, an average of 10 minutes | 
| degree of difficulty for intubation | the number of attempts at laryngoscopy and use of any rescue maneuvers, seniority of the anesthesiologist | through study completion, an average of 10 minutes | 
| degree of tissue oxygenation | O2 saturation | through study completion, an average of 10 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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preoxygenation, high-flow nasal cannula