Effect of End-inspiratory Pause on Gas Exchange During Mediastinal Mass Excision With CO2 Insufflation and One-lung Ventilation

NCT ID: NCT06956079

Last Updated: 2025-05-02

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Clinical Phase: NA
• Total Enrollment: 58 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2025-05-31
• Study Completion Date: 2027-03-10

Brief Summary

" Mediastinal mass excision is typically performed via video-assisted thoracoscopic surgery (VATS). To secure a clear surgical field, the ipsilateral lung must be deflated, achieved through one-lung ventilation (OLV) and intrathoracic CO₂ insufflation. However, OLV increases intrapulmonary shunt due to continued perfusion of the non-ventilated lung, potentially leading to hypoxemia and hypercapnia.

When performed in the supine position, gas exchange becomes more challenging compared to lateral decubitus due to limited gravitational redistribution of blood flow. Although CO₂ insufflation aids surgical exposure through passive lung deflation, it may also increase CVP and PCWP, reduce cardiac output, and raise PaCO₂, contributing to respiratory acidosis.

End-inspiratory pause (EIP), a ventilatory setting that pauses airflow at end-inspiration, prolongs alveolar gas exchange and improves ventilation-perfusion matching. Prior studies show EIP can enhance gas exchange, reduce microatelectasis, and improve CO₂ clearance in patients with acute lung injury. We therefore aimed to assess the effect of EIP application during VATS mediastinal mass excicion.

Conditions

Mediastinal Mass Requiring Video-assisted Surgical Excision

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: SUPPORTIVE_CARE
• Blinding Strategy: TRIPLE

Study Groups

EIP-first group

EIP is applied for 20 minutes immediately after the initiation of one-lung ventilation, followed by conventional mechanical ventilation.

Group Type: EXPERIMENTAL

EIP-first

Intervention Type: PROCEDURE

EIP is applied for 20 minutes immediately after the initiation of one-lung ventilation, followed by conventional mechanical ventilation.

EIP-later group

Conventional mechanical ventilation is applied for 20 minutes after the initiation of one-lung ventilation, followed by EIP application.

Group Type: ACTIVE_COMPARATOR

EIP-later

Intervention Type: PROCEDURE

Conventional mechanical ventilation is applied for 20 minutes after the initiation of one-lung ventilation, followed by EIP application.

Interventions

EIP-first

EIP is applied for 20 minutes immediately after the initiation of one-lung ventilation, followed by conventional mechanical ventilation.

Intervention Type: PROCEDURE

EIP-later

Conventional mechanical ventilation is applied for 20 minutes after the initiation of one-lung ventilation, followed by EIP application.

Intervention Type: PROCEDURE

Eligibility Criteria

Inclusion Criteria

• Adult patients aged 20 to 80 years scheduled for video-assisted thoracoscopic mediastinal tumor resection.
• American Society of Anesthesiologists (ASA) physical status classification of II (patients with mild systemic disease) or III (patients with severe systemic disease limiting activity).

Exclusion Criteria

• Moderate to severe chronic obstructive pulmonary disease (COPD) according to GOLD criteria: defined as FEV₁/FVC < 0.7 and FEV₁ ≤ 80% of predicted on pulmonary function testing.
• Diffusion capacity of the lung for carbon monoxide (DLCO) < 80% of predicted.
• History of pneumothorax or presence of bullae or blebs on preoperative imaging.
• Inability to read or understand the subject information sheet and consent form.

• Minimum Eligible Age: 20 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Yonsei University

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Locations

Severance hospital

Seoul, , South Korea

Countries

South Korea

Other Identifiers

4-2025-0232

Identifier Type: -

Identifier Source: org_study_id