Effects of Oxygen Supply After Lung Isolation in Thoracic Surgery

NCT05946707 | Completed

• 1 other identifier: 1051/2023
• Study Type: interventional
• Target: 55
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this randomized clinical trial is to compare a liberal versus restrictive oxygen supply (fraction of inspired oxygen, FiO2) strategy in patients scheduled for thoracic surgery requiring one-lung ventilation during lung isolation. The primary and secondary outcome parameters are:

• oxygenation of the blood after 30 minutes of one-lung ventilation, assessed by PaO2/FiO2 ratio
• time to lung collapse after start of one-lung ventilation Participants in the control goup will receive an oxygen content of 100% before lung isolation, which will be subsequently decreased to achieve normoxia or mild hyperoxia (PaO2 of 75-120 mmHg). The intervention group will receive the previous, during two-lung ventilation set, oxygen content and after lung isolation oxygen supply will be increased to secure adequate oxygenation of the blood (PaO2 75-120 mmHg) during one-lung ventilation. The investigators hypothesize, that a higher fraction of inspired oxygen may impede hypoxic pulmonary vasoconstriction of the collapsed lung and thus decrease overall oxygenation performance during one-lung ventilation. Secondary endpoint will be the time to lung collapse, as a lower fraction of inspired oxygen and thus a higher nitrogen content may impede lung collapse.

Conditions

Mechanical Ventilation; Thoracic Surgery; One-Lung Ventilation

Keywords

Oxygen supply; Hypoxic pulmonary vasoconstriction; Lung collapse; Flow-controlled Ventilation

Outcome Measures

Primary Outcomes (1)

• oxygenation of the blood

  Oxygenation of the blood will be assessed by the paO2/FiO2 ratio and compared between groups.

  Primary outcome timepoint is defined at 30 minutes after start of OLV

Secondary Outcomes (2)

• lung collapse

  Lung collapse will be assessed and recorded as no collapse, partial collapse or complete collapse at 10, 20, 30 and 60 minutes after start of one-lung ventilation.

• postoperative pulmonary complication

  Follow-up will be completed after end of hospital stay or 30-days of hospital stay.

Study Arms (2)

high oxygen: decremental FiO2 titration

ACTIVE COMPARATOR

Five minutes before lung isolation fraction of inspired oxygen will be increased to 1.0, representing the standard procedure for one-lung ventilation. 10, 20 and 30 minutes after OLV initiation paO2 obtained from arterial blood gas analysis will be measured and FiO2 titrated to achieve a paO2 of 75-120 mmHg.

Drug: liberal oxygen supply

low oxygen: incremental FiO2 titration

EXPERIMENTAL

Before lung isolation fraction of inspired oxygen will be maintained as previously set to guarantee normoxia (SpO2 \>92%). During OLV SpO2 will be continuously monitored and FiO2 adjusted to keep SpO2 \>92%. Additionally after 10, 20 and 30 minutes after OLV initiation paO2 obtained from arterial blood gas analysis will be measured and FiO2 more precisely titrated to achieve a paO2 of 75-120 mmHg.

Drug: restrictive oxygen supply

Interventions

restrictive oxygen supply DRUG

Oxygen supply will be limited to guarantee normoxia at the beginning of OLV.

low oxygen: incremental FiO2 titration

liberal oxygen supply DRUG

Oxygen supply will be maximized to 100% at the beginning of OLV

high oxygen: decremental FiO2 titration

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Male and female subjects ≥ 18 years
• Elective thoracic surgery requiring OLV
• American Society of Anesthesiologists physical status classification I-III
• Written informed consent

You may not qualify if:

• Emergency surgery
• Female subjects known to be pregnant
• Known participation in another interventional clinical trial
• Empyema evacuation or signs of pulmonary infection

Sponsors & Collaborators

• Medical University Innsbruck: lead

Study Sites (1)

Medical University Innsbruck

Innsbruck, Tyrol, 6020, Austria

Location

MeSH Terms

Conditions

Pulmonary Atelectasis

Condition Hierarchy (Ancestors)

Lung Diseases; Respiratory Tract Diseases

Study Officials

• Patrick Spraider, MD

  Medical University of Innsbruck, Department of Anesthesiology and Intensive Care Medicine

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Masking Details: Study participants will be randomized after induction of general anesthesia and thus are not aware of the treatment arm, which solely differs at the time of lung isolation.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: non-blinded, randomized, controlled trial

Study Record Dates

• First Submitted: May 25, 2023
• First Posted: July 14, 2023
• Study Start: July 19, 2023
• Primary Completion: March 7, 2024
• Study Completion: March 7, 2024
• Last Updated: March 12, 2024

Record last verified: 2023-05

Data Sharing

• IPD Sharing: Will not share

Locations

AU (1)