Use of Flow-Controlled Ventilation During CT-Guided Percutaneous Liver Tumor Ablation (EVOLVE)

Flow-controlled Ventilation During Percutaneous CT-guided Liver Tumor Ablation

Tumors in the liver can be treated using percutaneous ablation. At the Amsterdam UMC, this procedure is often performed under CT guidance by an interventional radiologist. The available ablation techniques include thermal ablation (microwave ablation (MWA) and radiofrequency ablation (RFA)) and non-thermal ablation (irreversible electroporation (IRE)). Thermal ablation is performed under general anesthesia or deep sedation, whereas non-thermal ablation is always performed under general anesthesia.

Flow-controlled ventilation (FCV) is a ventilation technique in which increased diaphragm stability is observed due to a continuous flow during both inspiration and expiration. This contrasts with volume- or pressure-controlled ventilation, where active inspiration is followed by passive expiration through an increase in pressure or flow, leading to greater diaphragm movement during the ventilation cycle. With volume- or pressure-controlled ventilation, diaphragm position fluctuates between inspiration and expiration, requiring temporary pauses in ventilation (apnea; allowing the diaphragm to become motionless) during ablation needle positioning.

During volume- or pressure-controlled ventilation and the associated apnea periods, increased formation of atelectasis is often observed. This results in changes in diaphragm position during and after each apnea, which can complicate accurate needle placement. With FCV, apnea is not necessary-the continuous flow results in minimal diaphragm excursion and can be maintained throughout the entire procedure without interruption.

Both ventilation modes are currently used during CT-guided percutaneous ablation of liver and pancreatic tumors. However, the choice of ventilation technique presently lies with the attending anesthesiologist. In practice, some anesthesiologists prefer volume- or pressure-controlled ventilation, as these are traditionally the most commonly used modes. Others opt for FCV due to its minimal effect on diaphragm excursion and its potentially beneficial effects on atelectasis formation and intraprocedural image quality.

Given the subdiaphragmatic location of both organs and the presence of critical surrounding structures that must be preserved during the procedure, interventional radiologists find FCV particularly advantageous. Moreover, continuous ventilation without apnea is preferred by anesthesiologists, as it avoids periods of reduced oxygenation.

FCV is an already approved ventilation technique at Amsterdam UMC and is used during percutaneous ablations, surgeries performed by ENT and pulmonary specialists, and in the intensive care unit for critically ill patients. Through this study, the investigators aim to evaluate the use of FCV as a ventilation technique during CT-guided percutaneous ablations of liver tumors and to compare it with volume- or pressure-controlled ventilation.

Study Overview

• Status: Completed
• Conditions: Ventilation; Ablation Techniques
• Intervention / Treatment: Device: Flow controlled ventilation

• Study Type: Observational
• Enrollment (Actual): 41

Contacts and Locations

Study Locations

• Netherlands
  • Amsterdam, Netherlands, 1081HV
    • Amsterdam UMC, location VUmc

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

Patients eligible for CT-guided percutaneous ablation of liver tumors

Description

Inclusion Criteria:

• Clinical indication for CT-guided percutaneous ablation of one or more liver tumours
• Approval for general anaesthesia

Exclusion Criteria:

• Procedures performed under procedural sedation
• Uncontrolled asthma, and (4) COPD classified as Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage III or IV
• No signed informed consent form

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Flow controlled ventilation; Patients recieving CT-guided percutaneous ablation, ventilated with flow controlled ventilation	Device: Flow controlled ventilation; Flow controlled ventilation will be investigated during CT-guided percutaneous ablation of liver tumors
Volume controlled ventilation; Patients recieving CT-guided percutaneous ablation, ventilated with volume controlled ventilation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Switch from flow controlled ventilation to volume controlled ventilation	Switch if deemed necessary by the anesthesiologist performing the ventilation.	During the CT-guided percutaneous ablation procedure

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Image-based analyses	Comparison of diaphragm movement by segmenting the pulmonary bases in pre- and post-ablation images and assessment of intra-procedural atelectasis formation.	During the ablation procedure
Modified five-point Surgical Rating Scale	Completed by the interventional radiologist to assess the suitability of FCV for the procedure. Score can vary from 0-25, where 25 is the highest score.	Directly after the ablation procedure

Collaborators and Investigators

• Sponsor: Academisch Medisch Centrum - Universiteit van Amsterdam (AMC-UvA)

Study record dates

Study Major Dates

• Study Start (Actual): August 20, 2024
• Primary Completion (Actual): May 20, 2025
• Study Completion (Actual): November 20, 2025

Study Registration Dates

• First Submitted: November 25, 2025
• First Submitted That Met QC Criteria: December 5, 2025
• First Posted (Actual): December 18, 2025

Study Record Updates

• Last Update Posted (Actual): December 18, 2025
• Last Update Submitted That Met QC Criteria: December 5, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Liver tumor; Percutaneous ablation; Flow controlled ventilation; Volume controlled ventilation; CT-guided ablation
• Additional Relevant MeSH Terms: Pathologic Processes; Neoplasms by Site; Neoplasms; Respiratory Tract Diseases; Neoplasms by Histologic Type; Digestive System Neoplasms; Digestive System Diseases; Respiration Disorders; Liver Diseases; Neoplasms, Glandular and Epithelial; Adenocarcinoma; Liver Neoplasms; Carcinoma; Pathological Conditions, Signs and Symptoms; Carcinoma, Hepatocellular; Respiratory Aspiration
• Other Study ID Numbers: METc-number: 2024.0386

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No