Hyperoxygenation in Anesthetized Children

Study Overview
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Brief Summary
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This study is aiming at assessing the effect of inspired oxygen fraction during general anesthesia on children's lung mechanics and volume. More specifically, the temporal change in end-expiratory lung volume (EELV) and respiratory system resistance and elastance during the perioperative period will be characterized in order to define the the effect of high inspired fraction of oxygen on lung function.

Detailed Description
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High-enriched oxygen fractions (FiO2)are common practice during general anesthesia both to ensure normoxemia despite intrapulmonary shunts and to provide security in case of adverse events. However, high-inspired oxygen fraction may decrease ventilation-perfusion ratios and its benefits are still unproven in children. The investigators aim at assessing the benefits and potential adverse effects of high-inspired oxygen fraction in two groups of children receiving either 30% FiO2 or 80% FiO2 during maintenance of anesthesia. Nitrogen multiple breath washout technique and forced oscillation technique will be used to measure end-expiratory lung volume (EELV) and airway resistance (Rrs) and respiratory elastance (Xrs) respectively. These measurements will be obtained before the general anesthesia, one hour and one day after the procedure.

Official Title
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Impact of Intraoperative High Inspired OXygen Fraction on Pulmonary Function, Surgical Site Infection, Postoperative Nausea and Vomiting in PEDiatric Anesthesia, the OXPED Study

Conditions
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Hyperoxia

Intervention / Treatment
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* Other: Oxygen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiology (ASA) physical status I and II Body mass index < 30 kg/m2 Scheduled for elective surgery in the supine position lasting < 200 min General Anesthesia with tracheal intubation Exclusion Criteria: Patients hospitalized more than 24 h before the operation History or clinical signs of heart or lung disease Upper respiratory tract infection < 2 weeks prior to surgery Predictable difficult airway History of apnea Abdominal or thoracic surgery Lack of cooperation, language barrier

Ages Eligible for Study
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Minimum Age: 4 Years
Maximum Age: 16 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Group High FiO2<br>Children will receive Fi02 100% during induction of anesthesia until end tidal oxygen concentration (Et 02) of 90% before intubation, anesthesia will be maintained with Fi02 of 80%. Then, shortly before the planned extubation, Fi02 will be increased to 100%. | Other: Oxygen<br>* Delivery of high concentration of oxygen at induction, maintenance and extubation of children under general anesthesia.<br>|
| Active Comparator: Group Low FiO2<br>Children will receive Fi02 80% until Et 02 70% before intubation, anaesthesia will be maintained with Fi02 35%. Then, shortly before the planned extubation, Fi02 will be increased again to 80%. | Other: Oxygen<br>* Delivery of high concentration of oxygen at induction, maintenance and extubation of children under general anesthesia.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative changes in lung volume in children receiving low (35%) or high (80%) intraoperative fraction of oxygen | Measurement of end-expiratory lung volume by nitrogen wash-out technique | 24 hours | 
| Postoperative changes in airway resistance in children receiving low (35%) or high (80%) intraoperative fraction of oxygen | Measurement of airway resistance and respiratory system elastance by forced oscillation technique | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Respiratory complications | Assessing intraoperative (bronchospasm, laryngospasm, oxygen desaturation, airway obstruction) and postoperative (hypoxemia, atelectasis, pneumonia) complications | 1 month | 
| Postoperative nausea and vomiting |  | 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Lung Volume Measurements, airway resistance, general anesthesia