Neck Movement Implicate the Tracheal Tube-tip Displacement in Pediatric Surgery

Study Overview
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Brief Summary
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This study evaluates the effect of head and neck movement in children on endotracheal tube (ETT) tip displacement undergoing head-and-neck surgeries. The tube-tip displacement will be measured using flexible fiberoptic bronchoscope.

Detailed Description
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In clinical application, especially in head-and-neck surgeries, the operators often change the position of children's head-neck for easy operating. Flexing the head resulted in the ETT moving towards the carina, and extension resulted in the tube being displaced in the opposite direction. Head and neck movement change the length of trachea as well: extending the head resulted in the extension of trachea, while flexing resulted in the opposite. Serious complications following from head and neck movement, such as accidental extubation and endobronchial intubation, threat children's life. In pediatric anesthesia, insertion depth (cm) of orotracheal intubation equals to age/2+12, according to classic intubation formulae. The ETT will be put in the depth calculated by the classic formulae under general anesthesia. The distance of ETT-tip displacement and the length change of trachea will be measured as the head and neck placed as follows: fully extended, neutral position, or fully flexed. These three head and neck positions imitate the head-neck movement during those head-and-neck surgeries.

Official Title
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Neck Flexion and Extension Implicate the Tracheal Tube-tip Displacement in Children Undergoing Head and Neck Surgeries

Conditions
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Pediatric Anesthesia, Tracheal Intubation

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: subject has elective head-and-neck surgery schedule subject will have orotracheal intubation under general anesthesia Exclusion Criteria: subject has malformations of the trachea or bronchus on chest X-ray subject has spinal deformity subject has difficulties in neck flexion or extension subject has neck pain

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum Age: 14 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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Distance of trachea carina (TC) to endotracheal tube (ETT) tip | Measure the distance between trachea carina to the tip of ETT in three different neck-head positions: fully flexion, neutral positon and fully extension. | 10min (time that the measurement need) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Distance of tracheal length | Tracheal length equals the distance between trachea carina (TC) to posterior vocal commissure. Measure Tracheal length in three different neck-head positions: fully flexion, neutral positon and fully extension. | 10min (time that the measurement need) | 
| Serious complication of unexpected displacement of the endotracheal tube: accidental extubation | When the operator put the child's neck into extension position, accidental extubation may occur, which can lead to hypoxia and asphyxia. | intraoperative | 
| Serious complication of unexpected displacement of the endotracheal tube: endobronchial intubation. | When the operator put the child's neck into flexion position, accidental endobronchial intubation may occur, which can lead to one-lung ventilation and pulmonary edema. | intraoperative | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pediatric, intubation, neck movement