Atelectasis Formation Using HFJV During Stereotactic Solid Organ Ablations

Atelectasis Formation Using High Frequency Jet Ventilation During Stereotactic Solid Organ Ablations

Atelectasis formation using HFJV during stereotactic solid organ ablations.

Primary endpoint will be to study the formation of atelectasis during HFJV. Secondary endpoint will be to study liver displacement over time. Reference groups will be found in previous published articles as referred to above.

Materials and methods: A radiological protocol has been made for the CT-scanner to take 10 cm volume Scans of the lower part of the lung. The scans will have its' lower border tangential to the top of the diaphragm. The first scan will be performed in the same session as the routine scan of the liver is performed after the patient is anesthetized. These Scans will then be repeated every 15 minute during the first 45 minutes. Arterial bloodgas analysis, transcutaneous CO2, blood pressure, saturation as well as parameters from the jet ventilator and the standard ventilator will be recorded.

Study Overview

• Status: Completed
• Conditions: Atelectasis; High Frequency Jet Ventilation
• Intervention / Treatment: Procedure: HFJV

Detailed Description

The use of HFJV in abdominal surgery as well as in out-of-operating theatre environment, is not well studied. In percutaneous liver thermal ablation the patient is anesthetized and intubated on the CT-bed where the liver ablation procedure is performed. Atelectasis is formed as soon as the patient is supine. Anesthesia itself also contributes to this. In extreme cases almost half the lung can be collapsed during anaesthesia, before any surgery has taken place.

The investigators have noticed that during this specific surgery, dynamic lung compliance does not necessarily worsen during HFJV but rather being unchanged or in some cases even becoming better and want to study this further and investigate the formation of atelectasis during HFJV. There are studies where atelectasis has been measured in a similar way as in this planned study, that is, with thin axial CT-scans at representative levels of the lung. This is during conventional lung ventilation, and has not yet been studied during HFJV.

Inclusion criteria: A total of n= 25 patients planned for elective liver tumor thermal ablation will be recruited after written informed consent.

Exclusion criteria: Patients 1/ under the age of 50 years, 2/with severe, poorly controlled lung disease.

The lung images will be saved in DICOM format and the tissue density will be analysed quantitatively. For each scan, the inner contour of each hemithorax will be manually drawn, excluding the chest wall, mediastinum, pleural effusions, and regions representing partial volume effects. Liver displacement can be measured from the routine CT-scans taken before and after the procedure.

Statistical methods: Chi2-analysis will be used to calculate the percentage of atelectasis in the lung.

Power calculation: Since the rate of atelectasis formation in the study groups is not known, it is impossible to perform power calculation for this trial. This study may clarify this issue in the planning of further studies.

This study may contribute to more knowledge about HFJV and its' effect on lung physiology, it may also contribute as a generator of new hypothesis and it might be a follow up study where the effect of alveolar recruitment maneuver (ARM) is studied.

• Study Type: Observational
• Enrollment (Actual): 25

Contacts and Locations

Study Locations

• Sweden
  • Stockholm, Sweden, 18288
    • Karolinska Institute Danderyd hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

All patients referred for computed tomography guided ablation of liver tumours.

Description

Inclusion Criteria:

• All consecutive patients admitted to and by the surgeon planned for liver thermal ablation with cascination navigation system (requiring high frequency jet ventilation) from start date 25th of October, until a total number of 25 patients are included.

Exclusion Criteria:

• Age < 50 years old. Severe lung disease.

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Atelectasis formation using HFJV; Computed tomography scans are performed every 15 minute during the first 45 minutes during general anaesthesia using high frequency jet ventilation.	Procedure: HFJV; On High frequency jet ventilation, Every 15 minutes, after induction of general anaesthesia, a computed tomography of the lower part of the lungs are taken (10 cm volume, with the top of the right diaphragm as the lower border)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in formation of atelectasis during high frequency jet ventilation	Computed tomography Scans will be taken during general anaesthesia at the start of jet ventilation, t=0, and then at t=15 minutes, t=30 minutes and t=45 minutes. A total number of four scans will be performed in each study subject.	Time frame is during surgery.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change of liver displacement	Routine CT Scans taken during surgery will be studied to calculate liver displacement over time.	Time frame is during surgery.

Collaborators and Investigators

• Sponsor: Karolinska Institutet

Publications and helpful links

General Publications

• Reinius H, Jonsson L, Gustafsson S, Sundbom M, Duvernoy O, Pelosi P, Hedenstierna G, Freden F. Prevention of atelectasis in morbidly obese patients during general anesthesia and paralysis: a computerized tomography study. Anesthesiology. 2009 Nov;111(5):979-87. doi: 10.1097/ALN.0b013e3181b87edb.
• Denys A, Lachenal Y, Duran R, Chollet-Rivier M, Bize P. Use of high-frequency jet ventilation for percutaneous tumor ablation. Cardiovasc Intervent Radiol. 2014 Feb;37(1):140-6. doi: 10.1007/s00270-013-0620-4. Epub 2013 May 2.
• Magnusson L, Spahn DR. New concepts of atelectasis during general anaesthesia. Br J Anaesth. 2003 Jul;91(1):61-72. doi: 10.1093/bja/aeg085. No abstract available.
• Abderhalden S, Biro P, Hechelhammer L, Pfiffner R, Pfammatter T. CT-guided navigation of percutaneous hepatic and renal radiofrequency ablation under high-frequency jet ventilation: feasibility study. J Vasc Interv Radiol. 2011 Sep;22(9):1275-8. doi: 10.1016/j.jvir.2011.04.013. Epub 2011 Jun 23.

Study record dates

Study Major Dates

• Study Start (Actual): October 2, 2017
• Primary Completion (Actual): December 19, 2017
• Study Completion (Actual): December 19, 2017

Study Registration Dates

• First Submitted: December 4, 2017
• First Submitted That Met QC Criteria: December 14, 2017
• First Posted (Actual): December 20, 2017

Study Record Updates

• Last Update Posted (Actual): August 8, 2018
• Last Update Submitted That Met QC Criteria: August 7, 2018
• Last Verified: August 1, 2018

More Information

Terms related to this study

• Keywords: Computer tomography; Liver tumor thermoablation
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Lung Diseases; Pulmonary Atelectasis
• Other Study ID Numbers: 2017/1158-32

Drug and device information, study documents

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