Effectiveness of Detachment of the Breathing Circuit on the Rate of DLT Malposition After Postural Change

Effectiveness of Detachment of the Breathing Circuit on the Rate of the Double-lumen Endotracheal Tube Malposition After the Change of Position in Patients Undergoing Thoracic Surgery: a Randomized Controlled Trial

The goal of this clinical trial is to assess the incidence of double-lumen endobronchial tube displacement in patients undergoing thoracic surgery with a change in position, compared with double-lumen endobronchial tube malposition in chest surgery patients with a fixed breathing circuit. The study is to investigate: whether detaching the breathing circuit in patients undergoing thoracic surgery would reduce the rate of double-lumen endobronchial tube malposition, the incidence of postoperative pulmonary complications, and improve patient outcomes.

Participants will be randomly divided into a disconnected breathing circuit group and a breathing circuit connected group and after entering the operating room, the intravenous access will be opened, and blood pressure, heart rate, electrocardiogram, oxygen saturation, arterial pressure, and end-expiratory carbon dioxide will be monitored. Anesthesia induction will be performed by an anesthesiologist, and then the double-lumen endobronchial tube will be inserted under laryngoscopic guidance. Will the catheter be delivered to the expected depth, the double-lumen endobronchial tube will be connected to the anesthesia machine for mechanical ventilation.

Researchers will compare the malposition rate of the double-lumen endobronchial tube when the patient transitions from the supine to lateral decubitus position, the effect of single-lung ventilation, oxygen saturation at 5 and 10 minutes after single-lung ventilation, and postoperative recovery time.

Study Overview

• Status: Completed
• Conditions: Patient Positioning; Intratracheal Intubation
• Intervention / Treatment: Behavioral: Disengage the breathing circuit

• Study Type: Interventional
• Enrollment (Actual): 256
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • S
    • Jinan, S, China, 250021
      • Shandong Provincial Hospital Affiliated to Shandong First Medical University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• ASA I-II elective surgery for patients
• Patients undergoing thoracic surgery requiring a left-sided double-lumen endobronchial tube;
• Sign the informed consent form for this clinical study.

Exclusion Criteria:

• Mouth opening <3cm;
• History of previous difficult intubation;
• Patients with diseases of the upper respiratory tract and main bronchi;
• Cardiac insufficiency;
• People with liver dysfunction;
• Renal insufficiency;
• Previous stroke;
• Patients with severe obstructive ventilation dysfunction;
• Bronchial asthma or airway hyperresponsiveness;
• Patients who have participated in other clinical studies in the past 3 months.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Disengagement of the breathing circuit; When the patient's position is changed from the supine position to the lateral decubitus position, the anesthesiologist disengages the breathing circuit.	Behavioral: Disengage the breathing circuit; Disengage the breathing circuit when the position of the patient undergoing thoracic surgery changes
No Intervention: Connect the breathing circuit; When the patient's position is changed from the supine position to the lateral decubitus position, the anesthesiologist maintains the normal connection of the breathing line.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Malposition rate of a double-lumen endobronchial tube	Double-lumen endobronchial tube malposition is more than 5 mm away from the optimal position of the catheter. Severe malposition is the inability to see the upper left or lower left bronchial opening in the left common bronchi: the right upper lobe bronchial opening cannot be seen clearly in the right common bronchi; or bronchial cuffs more than 50% in the trachea.	Immediately after a change in body position

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effects of lung collapse	If the lung on the operative side is completely atrophied and the surgical field is satisfied, it indicates that the degree of lung atrophy is good. The surgeon will score the quality of lung collapse using a four-point ordinal scale (1= extremelypoor-no collapse of lung; 2= poor-partial collapse of lung with interference with surgical exposure; 3= good-total collapse, but the lung still had some residual air; and 4= excellent-complete collapse of lung with perfect surgical exposure).	5 and 10 minutes after the pleura opens
Blood oxygen saturation	An oxygen saturation below 94% is considered oxygen insufficiency	1 minute and 5 minutes after the change of position；1 minute, 5 minutes and 10 minutes after single-lung ventilation
PACU length of stay	The patient is awake and conscious	The time from the transfer to the PACU to the transfer out to ward, an average of an hour

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Partial pressure of carbon dioxide at the end of expiration	Determine the status of blood-lung ventilation and pulmonary blood flow	1 minute and 5 minutes after the change of position；1 minute, 5 minutes and 10 minutes after single-lung ventilation
Blood pressure	Make sure the patient's blood pressure is within the normal range	1 minute and 5 minutes after the change of position；1 minute, 5 minutes and 10 minutes after single-lung ventilation
Heart rate	Make sure the patient's heart rate is within the normal range	1 minute and 5 minutes after the change of position；1 minute, 5 minutes and 10 minutes after single-lung ventilation

Collaborators and Investigators

• Sponsor: Shandong Provincial Hospital
• Investigators: Principal Investigator: Jin Bao Mao, Ph.D., Shandong Provincial Hospital

Publications and helpful links

General Publications

• Lv S, Lv M, Du W, Zou Z, Zheng K, Qu J, Han X, Mao J. Does ventilator circuit disconnection during lateral positioning reduces the rate of double-lumen endotracheal tube displacement in thoracic surgery? a study protocol for a randomized controlled trial. Trials. 2026 Feb 28. doi: 10.1186/s13063-026-09567-w. Online ahead of print.

Study record dates

Study Major Dates

• Study Start (Actual): May 16, 2025
• Primary Completion (Actual): December 8, 2025
• Study Completion (Actual): December 8, 2025

Study Registration Dates

• First Submitted: November 21, 2023
• First Submitted That Met QC Criteria: December 23, 2023
• First Posted (Actual): December 26, 2023

Study Record Updates

• Last Update Posted (Actual): April 29, 2026
• Last Update Submitted That Met QC Criteria: April 24, 2026
• Last Verified: January 1, 2025

More Information

Terms related to this study

• Keywords: Double-Lumen Endobronchial Tube; Positional changes; Disengage; Breathing circuit; Malposition
• Additional Relevant MeSH Terms: Pathologic Processes; Respiratory Tract Diseases; Respiration Disorders; Respiratory Aspiration
• Other Study ID Numbers: MLv

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No