Endobronchial Intubation of Double-lumen Tube: Conventional Method vs Fiberoptic Bronchoscope Guide Method

Study Overview
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Brief Summary
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Double lumen tube (DLT) needs to be intubated to isolate ventilations of left and right lungs for thoracic surgery. Post-operative sore throat and hoarseness are more frequent with DLT intubation than with single one. Which is may because DLT is relatively thicker, harder, sideway curved and therefore more likely to damage the vocal cord or trachea during intubation, and advanced deeper to the carina and main bronchus level. In the conventional method of intubation, DLT is rotated 90 degrees and advanced blindly to the main bronchus level after DLT is intubated through vocal cord using the direct laryngoscopy. After the blind advancement, the sufficient tube position needs to be gained and confirmed with the fiberoptic bronchoscope. In the bronchoscope guide method, after DLT is intubated through vocal cord using the direct laryngoscopy, the pathway into the targeted main bronchus is secured using the fiberoptic bronchoscope which is passed through a bronchial lumen of DLT. And then DLT can be advanced through the guide of the bronchoscope. In this study, we intend to compare post-operative sore throat, hoarseness and airway injury between the two methods. We hypothesize that the bronchoscope guide method can reduce the post-operative complications and airway injury because surrounding tissues of the airway can be less irritated by DLT intubation in the guide method than in a conventional. For a constant guide effect, we use fiberoptic bronchoscopes with same outer diameter (4.1 mm) which can pass through a bronchial lumen of 37 and 39 Fr Lt. DLT and cannot pass through 35 Fr or smaller Lt. DLTs. <Lt. DLT size selection> male: ≥160 cm, 39 French; < 160 cm, 37 French female: ≥160 cm, 37 French; < 160 cm, contraindication

Official Title
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The Effect of Endobronchial Intubation of Double-lumen Tube on Post-operative Sore Throat, Hoarseness and Airway Injuries: A Comparison Between Conventional and Fiberoptic Bronchoscope-guided Intubation

Conditions
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Sore Throat, Intubation, Intratracheal, Postoperative Complications, Hoarseness, Soft Tissue Injuries, Thoracic Surgery

Intervention / Treatment
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* Procedure: Bronchoscope guided advancement
* Procedure: Conventional advancement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA (American Society of Anesthesiologists) class I - III Elective thoracic surgery Left-sided DLT intubation for one-lung ventilation Exclusion Criteria: Female, height < 160 cm Pre-existing sore throat, hoarseness or airway injury Duration of surgery > 6 h Upper respiratory tract infection Cervical spine diseases Presence of tracheostomy Pharyngeal neoplasm or abscess which can induce mechanical airway obstruction Mallampati score 4 Obesity (BMI ≥ 35 kg/m2) Obstructive sleep apnea (OSA) Craniofacial anomaly Cormack grade 3b or 4 History or high risk of difficult intubation / difficult mask ventilation Patients whom the direct laryngoscopy cannot be used for, because of weak teeth or small mouth opening Patients who refuse to participate in the study or from whom receive informed consent cannot be received.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 75 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Bronchoscope guide group<br>DLT is advanced into the main bronchus through the guide of fiberoptic bronchoscope (Bronchoscope guided advancement). | Procedure: Bronchoscope guided advancement<br>* During the anesthetic induction for thoracic surgery, Lt. DLT is intubated using the bronchoscope-guided method. The method is as follows. Lt. DLT is intubated through vocal cord using the direct laryngoscopy. Pass the fiberoptic bronschoscope through a bronchial lumen of Lt. DLT. Secure the pathway into the Lt. main bronchus by advancing the bronchoscope into the Lt. main bronchus. Lt. DLT can be advanced through the guide of the bronchoscope into Lt. main bronchus. After the advancement, the position of Lt. DLT can be confirmed using the fiberoptic bronchoscope. If necessary, the depth and direction of Lt. DLT should be modified.<br>|
| Active Comparator: Conventional group<br>DLT is advanced blindly to the main bronchus level (Conventional advancement). | Procedure: Conventional advancement<br>* During the anesthetic induction for thoracic surgery, Lt. DLT is intubated using the conventional method. The method is as follows. Lt. DLT is intubated through vocal cord using the direct laryngoscopy. Rotate Lt. DLT 90 degrees to the left side. Advance Lt. DLT blindly to main bronchus level. After the advancement, the position of Lt. DLT can be confirmed using the fiberoptic bronchoscope. If necessary, the depth and direction of Lt. DLT should be modified.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Post-operative sore throat (24 h) | The degree of throat pain (Visual Analogue Scale (VAS); 0, no pain; 10, most | 24 hour after tracheal extubation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Resistance against DLT passage through vocal cord | none/mild/severe | Intraoperative | 
| Resistance against DLT advancement | none/mild/severe | Intraoperative | 
| Intubation time | stop of initial mask ventilation - intubation through vocal cord | Intraoperative | 
| The number of attempts for intubation | The number of attempts for intubation through vocal cord | Intraoperative | 
| The number of right misplacement of Lt. DLT | The number of right misplacement of Lt. DLT confirmed using the fiberoptic bronchoscope after the advancement | Intraoperative | 
| Time for DLT positioning: stop of initial mask ventilation - success of the 1st fine DLT positioning | Time for DLT positioning: stop of initial mask ventilation - success of the 1st fine DLT positioning into Lt. main bronchus | Intraoperative | 
| Heart rate | Heart rate Just before Lt. DLT intubation / 2 min after success of the 1st fine DLT positioning | Intraoperative | 
| Mean arterial pressure | Mean arterial pressure Just before Lt. DLT intubation / 2 min after success of the 1st fine DLT positioning | Intraoperative | 
| IV PCA | Fentanyl usage with PCA | At 24 hours after the extubation | 
| Airway injury (Lt. main bronhcus, carina, trachea) | When spontaneous breathing of the patient starts after the thoracic surgery | Intraoperative | 
| Airway injury (vocal cord) | When spontaneous breathing of the patient starts after the thoracic surgery | Intraoperative | 
| Post-operative sore throat (1 h) | The degree of throat pain (Visual Analogue Scale (VAS); 0, no pain; 10, most pain) after tracheal extubation | 24 hours after tracheal extubation | 
| Post-operative hoarseness (1 h) | The incidence of hoarseness after tracheal extubation | 1 hour after tracheal extubation | 
| Post-operative hoarseness (24 h) | The incidence of hoarseness after tracheal extubation | 24 hour after tracheal extubation | 
| Oral dryness | The incidence of oral dryness | 24 hours after tracheal extubation | 
| Dysphagia | The incidence of dysphagia | 24 hours after tracheal extubation |