Anesthetic Gas Leakage in Children During Tonsillectomy: a Comparison of Cuffed and Uncuffed Tracheal Tubes

Study Overview
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Brief Summary
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Fires and operating room pollution may occur when anesthesia gases leak into the oropharynx during airway surgery. Investigators sought to measure the concentrations of anesthetic gases that leak into the mouth of children undergoing adenotonsillectomy using cuffed and uncuffed tracheal tubes during spontaneous and controlled ventilation.

Detailed Description
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For the past 6 decades, uncuffed tubes have been used for the children less than 8 years of age out of a fear that cuffed tubes would cause damage to the subglottic region. The correct size uncuffed tube creates a seal in the subglottis that has minimal pressure on the mucosa. However, cuffed tubes have become more widely used in children recently without causing damage to the mucosa. There is very little literature comparing the magnitude of the gas leaks with cuffed and uncuffed tracheal tubes particularly in children. Several authors suggest that the leak of nitrous oxide and sevoflurane with uncuffed tubes was much greater than with cuffed tubes. One important but poorly studied issue is the risk of an airway fire when cautery is used for tonsillectomy because a large leak of oxygen in the mouth could ignite a fire. It also remains unclear whether the mode of ventilation, spontaneous or controlled, affects the leak of gases into the mouth. One might expect that the gas leak with spontaneous ventilation is less than with controlled ventilation, but it may not matter in the context of the small concentrations of oxygen and sevoflurane that investigators use. To address all of these concerns, investigators designed this study to compare the concentrations of gases (oxygen, carbon dioxide, nitrous oxide and sevoflurane) in the oral cavity of children undergoing T&A with either cuffed or uncuffed tubes, during spontaneous and controlled ventilation.

Official Title
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Anesthetic Gas Leakage in Children During Tonsillectomy: a Comparison of Cuffed and Uncuffed Tracheal Tubes

Conditions
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Exposure to Environmental Pollution, Adverse Effect of Unspecified General Anesthetic

Intervention / Treatment
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* Drug: oxygen concentration
* Drug: nitrous oxide concentration
* Drug: carbon dioxide concentration
* Drug: sevoflurane concentration


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American society of anesthesiologists physical status 1 and 2; fasted scheduled for elective adenotonsillectomy Exclusion Criteria: refusal of consent by parents difficult tracheal intubation craniofacial anomalies gastroesophageal reflux malignant hyperthermia randomization to a tracheal tube is unacceptable.

Ages Eligible for Study
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Minimum Age: 1 Year
Maximum Age: 6 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Uncuffed tracheal tubes<br>After tracheal intubation with an uncuffed tube, the interventions will be the oxygen concentration, nitrous oxide concentration, carbon dioxide concentration and sevoflurane concentration measured in the tracheal tube compared with those in the oropharynx during spontaneous and controlled ventilation. | Drug: oxygen concentration<br>* oxygen concentration will be measured in the tracheal tube and oropharynx during spontaneous or controlled ventilation<br>* Other names: difference in the oxygen concentration;Drug: nitrous oxide concentration<br>* nitrous oxide concentration will be measured in the tracheal tube and oropharynx during spontaneous or controlled ventilation<br>* Other names: difference in the nitrous oxide concentration;Drug: carbon dioxide concentration<br>* carbon dioxide concentration will be measured from the tracheal tube and in the oropharynx during spontaneous or controlled ventilation<br>* Other names: difference in the carbon dioxide concentration;Drug: sevoflurane concentration<br>* sevoflurane concentration will be measured in the tracheal tube and oropharynx during spontaneous or controlled ventilation<br>* Other names: difference in the sevoflurane concentration;|
| Active Comparator: Cuffed tracheal tubes<br>After tracheal intubation with a cuffed tube, the interventions will be the oxygen concentration, nitrous oxide concentration, carbon dioxide concentration and sevoflurane concentration measured in the tracheal tube compared with those in the oropharynx during spontaneous and controlled ventilation. | Drug: oxygen concentration<br>* oxygen concentration will be measured in the tracheal tube and oropharynx during spontaneous or controlled ventilation<br>* Other names: difference in the oxygen concentration;Drug: nitrous oxide concentration<br>* nitrous oxide concentration will be measured in the tracheal tube and oropharynx during spontaneous or controlled ventilation<br>* Other names: difference in the nitrous oxide concentration;Drug: carbon dioxide concentration<br>* carbon dioxide concentration will be measured from the tracheal tube and in the oropharynx during spontaneous or controlled ventilation<br>* Other names: difference in the carbon dioxide concentration;Drug: sevoflurane concentration<br>* sevoflurane concentration will be measured in the tracheal tube and oropharynx during spontaneous or controlled ventilation<br>* Other names: difference in the sevoflurane concentration;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in the oxygen concentration with uncuffed and cuffed tubes during spontaneous or controlled ventilation | The differences in the oxygen concentration measured in the trachea and the oropharynx with uncuffed and cuffed tubes during spontaneous or controlled ventilation | 8 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in the nitrous oxide concentration with uncuffed and cuffed tubes during spontaneous or controlled ventilation | The differences in the nitrous oxide concentration measured in the trachea and the oropharynx with uncuffed and cuffed tubes during spontaneous or controlled ventilation | 8 months | 
| Difference in the carbon dioxide concentration with uncuffed and cuffed tubes during spontaneous or controlled ventilation | The differences in the carbon dioxide concentration measured in the trachea and the oropharynx with uncuffed and cuffed tubes during spontaneous or controlled ventilation | 8 months | 
| Difference in the sevoflurane concentration with uncuffed and cuffed tubes during spontaneous or controlled ventilation | The differences in the sevoflurane concentration measured in the trachea and the oropharynx with uncuffed and cuffed tubes during spontaneous or controlled ventilation | 8 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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oxygen, nitrous oxide, sevoflurane, carbon dioxide, endotracheal tube, respiration