Bronchial Blocker for One-lung Ventilation in Cardiac Surgery

Study Overview
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Brief Summary
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To investigate if bronchial blocker is more suitable for one-lung ventilation during thoracoscope assisted mitral valve replacement surgery with Cardiopulmonary Bypass than the double-lumen endobronchial tube.

Detailed Description
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Postoperative hoarseness, sore throat, and vocal cord injuries are common complications after general anesthesia. The incidence of postoperative hoarseness is as frequent as 50% after short-term tracheal intubation. In the past, several risk factors for postoperative hoarseness and laryngeal injury have been identified, including demographic factors, quality of tracheal intubation and technical factors such as endotracheal tube size. One-lung ventilation during thoracotomy can be achieved via two basic techniques: (1) use of a double-lumen endotracheal tube (DLT) consisting of an endotracheal and an endobronchial lumen allowing independent single-lung ventilation ; or (2) use of an endobronchial blocker such as the Arndt blocker, which allows lung collapse distal to the occlusion. It has been recently demonstrated that DLT and endobronchial blocker are similar in their efficacy to achieve lung isolation for elective thoracic surgery. No data are available yet about the influence of the chosen technique on postoperative hoarseness, vocal cord injuries, sore throat, and bronchial injuries. Published data of Stout et al. imply that the incidence of postoperative hoarseness and vocal cord injury might be directly correlated with size of the used endotracheal tube. During thoracoscope assisted mitral valve replacement cardiac surgery, excellent lung isolated was not required. One-lung ventilation with the other lung collapsed is used to achieve a better exposure and assist the surgery. During the cardiac surgery under cardiopulmonary bypass, heparinization will lead to uncontrolled hemorrhage if there is endotracheal tube insertion associated injury. In addition, DLTs need to be exchanged for a single-lumen tube before the patient transferring to cardiac care unit for postoperative ventilatory support. This may result in second time injury. Investigators hypothesized that using a bronchial blocker to achieve one-lung ventilation may result in a lower incidence of clinically relevant laryngeal and bronchial morbidity after thoracoscope assisted mitral valve replacement cardiac surgery compared with a control group intubated with a DLT.

Official Title
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The Use of Bronchial Blocker Versus Double Lumen Tube for One-lung Ventilation During Thoracoscope Assisted Mitral Valve Replacement

Conditions
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Complication of Ventilation Therapy, Intubation Complication, Postoperative; Dysfunction Following Cardiac Surgery

Intervention / Treatment
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* Device: double-lumen endotracheal tube (DLT group)
* Device: endobronchial blocker (BB group)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: New York Heart Association (NYHA)I-III level. scheduled for thoracoscope assisted mitral valve surgery under surgery provide with informed consent. Exclusion Criteria: emergency surgery. preoperative pulmonary diseases, such as chronic obstructive pulmonary disease, atelectasis. preoperative voice hoarse or sore throat. involved in other clinical trials within 3 months . Cannot cooperate with language understanding disorders or psychological problems.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: DLT group<br>In this arm, patient will be intubated with a double lumen endotracheal tube | Device: double-lumen endotracheal tube (DLT group)<br>* In this arm, after anesthesia induction, a double lumen endotracheal tube will be intubated for one-lung ventilation<br>|
| Experimental: BB group<br>In this arm, patient will be intubated with an endobronchial blocker | Device: endobronchial blocker (BB group)<br>* In this arm, after anesthesia induction, an endobronchial blocker will be intubated for one-lung ventilation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| clinically relevant laryngeal and bronchial morbidity | incidence of clinically relevant laryngeal and bronchial morbidity will be recorded, including postoperative hoarseness, sore throat, and vocal cord injuries, pulmonary complications | perioperative period | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart Rate | Heart rate in BPM will be recorded at right before intubation (T1), at intubation (T2), and at three minutes after intubation (T3). | perioperative period | 
| Central Venous Pressure | Central venous pressure in cmH2O will be recorded at right before intubation (T1),at intubation (T2), and at three minutes after intubation (T3). | perioperative period | 
| Blood Pressure | Systolic blood pressure, diastolic blood pressure and mean arterial pressure all in mmHg will be recorded at right before intubation (T1),at intubation (T2), and at three minutes after intubation (T3). | perioperative period | 
| the Duration of Ventilation | It is the duration of ventilation, prolonged ventilation is defined as patients remaining on the ventilator for more than 48 hours | The duration of ventilation in minutes will be recorded at time from intubation to extubation, an expected average of 18 hours. | 
| Length of Postoperative Hospital Stay | Recorded the time of postoperative hospital stay in days. | Length of postoperative hospital stay in days will be recorded which is defined as the time from surgery to hospital discharge, an expected average of 10 days | 
| Length of CCU Stay | It is the length of stay in cardiac ICU | Length of CCU stay in hours will be recorded which is defined as the time stay in the cardiac intensive care unit, an expected average of 3 days. |