Effect of Head Turn on Double-Lumen Tube Alignment

Taipei Veterans General Hospital, Taiwan35 enrolled

Overview

This study evaluated how simple external airway maneuvers affect the alignment of the left main bronchus during placement of a left-sided double-lumen endotracheal tube. Adults undergoing elective thoracic surgery requiring one-lung ventilation were enrolled. During double-lumen tube placement, a fiberoptic bronchoscope was used to continuously view the airway. Each participant underwent three sequential maneuvers: rightward displacement of the trachea, turning the head 45 degrees to the right, and turning the head 45 degrees to the left. The investigators measured how far the opening of the left main bronchus moved on the bronchoscopic image and whether it crossed the center of the image. The purpose of the study was to determine how these maneuvers change airway alignment and whether they may help guide a left-sided double-lumen tube toward the left main bronchus.

Study Type

INTERVENTIONAL

Allocation

Purpose

BASIC_SCIENCE

Masking

NONE

Enrollment

Conditions

Double-Lumen Endotracheal Tube Placement

Interventions

A lateral force was applied externally at the left cricothyroid level to displace the trachea toward the right. The force was increased until maximal bronchoscopic displacement was observed. Peak applied force was recorded using a digital force gauge. Bronchoscopic alignment and horizontal displacement of the left main bronchus were assessed during the maneuver.

Eligibility

Sex: ALL

Medical Language ↔ Plain English

Inclusion Criteria: * Patients scheduled for elective thoracic surgery requiring lung isolation with a left-sided double-lumen endotracheal tube * American Society of Anesthesiologists (ASA) physical status I-III * Provided written informed consent Exclusion Criteria: * Known severe cervical spine pathology or cervical instability * History of cervical spine surgery * Significant anatomical abnormalities of the upper airway * Head or neck malignancy or obstructing airway neoplasm * Presence of a tracheostomy

Outcomes

Primary Outcomes

Midline Crossing of the Left Main Bronchus

Midline crossing was defined as a change in the position of the left main bronchus from the left side to the right side of the midline of the bronchoscopic image following each airway maneuver. The position of the left main bronchus was assessed using real-time fiberoptic bronchoscopy with the bronchoscope maintained 2 cm proximal to the carina. Midline crossing was recorded as a binary outcome (yes/no) for each maneuver.

Time frame: During the airway maneuver, immediately after each maneuver was applied

Secondary Outcomes

Relative Horizontal Displacement of the Left Main Bronchus

Relative horizontal displacement was defined as the difference in the horizontal position of the left main bronchus before and during each airway maneuver, expressed as a percentage (Δ%) of the total width of the bronchoscopic image. The right edge of the left main bronchus was used as the reference point. Positive values indicated rightward displacement and negative values indicated leftward displacement. Measurements were obtained from bronchoscopic images with the bronchoscope maintained 2 cm proximal to the carina.