Changes in Pleural Cavity Volume and Surgical Exposure

Study Overview
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Brief Summary
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The investigators want to investigate if a diaphragmatic traction-suture affects the pleural cavity volume, as well as improves visual overview of a surgical field during minimally invasive thoracic surgery.

Detailed Description
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A visually good surgical field is essential in performing safe and optimal dissection of anatomical structures during Video Assisted Thoracoscopic Surgery (VATS). A number of patients referred to VATS-surgery appear with an elevated diaphragm, reducing visibility and complicating safe surgical techniques, thus entailing conversion from VATS into an open Thoracotomy. Some surgeons handle the decreased visibility due to an elevated diaphragm by increasing the amount of ports during VATS. Others have benefited from attaching a traction suture on the diaphragmatic posterior tendinous part, thus flatting the diaphragmatic dome when the suture is tightly retracted through the camera-port. It turns out that most thoracic surgery clinics are not familiar with this technique. There are also no articles regarding this topic in medical literature. We want to investigate if the diaphragmatic traction-suture affects the pleural cavity volume, as well as improves visual overview of a surgical field during minimally invasive thoracic surgery.

Official Title
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Changes in Pleural Cavity Volume and Surgical Exposure Through Suture Retraction of the Diaphragm During VATS Procedures

Conditions
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Thoracic Cancer

Intervention / Treatment
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* Procedure: Diaphragmatic traction-suture


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: known or suspected lung cancer scheduled for VATS-surgery perioperative finding of elevated diaphragma Exclusion Criteria: not willing to give informed consent. perioperative finding of pleural adherences perioperative finding without an elevated diaphragma

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: During video-assisted thoracoscopic surgery a diaphragmatic traction-suture is placed posteriorly at the border between the central tendinous part and the peripheral muscular part. Body temperate saline solution is then poured into the pleural cavity until the cavity is filled up to the soft-tissue retractor in the utility port. The volume of saline in the pleural cavity is then measured and registered before and after distal contraction of the diaphragmatic traction suture through the camera port. Subsequently the surgeon will be asked to evaluate and rate the surgical field visual overview, before and after contraction of the suture. Furthermore, anonymized video recordings focusing on the pleural cavity visual overview before and after distal contraction of the suture, will be presented to specialist thoracic surgeons for a blinded evaluation.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Before pulling diaphragmatic suture<br>Measurement of pleural cavity volume and visual overview before pulling diaphragmatic suture | Procedure: Diaphragmatic traction-suture<br>* Measurement of pleural cavity volume before pulling the diaphragmatic traction-suture Measurement of pleural cavity volume after pulling the diaphragmatic traction-suture<br>|
| Experimental: After pulling diaphragmatic suture<br>Measurement of pleural cavity volume and visual overview after pulling diaphragmatic suture | Procedure: Diaphragmatic traction-suture<br>* Measurement of pleural cavity volume before pulling the diaphragmatic traction-suture Measurement of pleural cavity volume after pulling the diaphragmatic traction-suture<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pleural cavity volume before | Pleural cavity volume (ml) before distal retraction of the diaphragmatic traction suture. | 1 minute after applying the traction suture | 
| Pleural cavity volume after | Pleural cavity volume (ml) after distal retraction of the diaphragmatic traction suture. | 2 minute after applying the traction suture | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual overview | The surgeon's evaluation of the surgical field visual overview before and after distal retraction of the diaphragmatic traction suture using a numeric rating scale (1-10). | 1 minute after applying the traction suture |