Feasibility Study of Novice-Performed Lung Ultrasound for Pneumothorax Detection After Cardiac Surgery

The CLEAR Vanguard Feasibility Study: Comparative Evaluation of Novice-Performed Lung Ultrasound Versus Chest X-Ray for Pneumothorax Detection Post-Chest Tube Removal in Cardiac Surgery Patients

What is the purpose of this study? This study is being done to find out if medical trainees (such as residents and fellows) can learn to use lung ultrasound to detect a collapsed lung (pneumothorax) after heart surgery.

Who is participating in the study? Adults who have recently had heart surgery and are having their chest tubes removed in the intensive care unit may be able to join.

What will happen during the study? After chest tubes are removed, a trained medical trainee will use a small ultrasound device to check the lungs at the bedside. The patient will also have a chest X-ray, which is the usual test. The results from the ultrasound will be compared to the chest X-ray and reviewed by expert doctors.

What is the goal of the study? The goal is to see if it is possible to train medical trainees to use lung ultrasound safely and accurately in real hospital settings. The results will help plan a larger study in the future.

This is a feasibility study to test whether lung ultrasound can be used by medical trainees to detect pneumothorax (collapsed lung) after heart surgery, instead of using a chest X-ray.

Collapsed lungs can happen after chest tubes are removed, which is a common step after heart surgery. While chest X-rays are usually used to check for this, they can sometimes miss cases or take time to complete. Lung ultrasound is a fast, safe, and radiation-free tool that can be done right at the bedside.

In this study, medical trainees-such as anesthesia residents, critical care fellows, or internal medicine residents-will receive focused training on how to use lung ultrasound. After training, they will perform lung ultrasound exams on patients within two hours after chest tube removal. These results will be compared to chest X-rays, and also reviewed by expert doctors who are blinded to the trainee's findings.

The study will take place at three large hospitals in Ontario, Canada. It will include about 120 patients in total. The study team will look at how well trainees follow the protocol, how accurate their ultrasound readings are, and how patients feel about having ultrasound done at the bedside.

This study does not involve any new treatments or medications. The purpose is to see if lung ultrasound can be safely and effectively performed by trainees, and whether a larger study should be done in the future to confirm its benefits.

Inclusion Criteria:

• Age 18 years or older
• Undergoing cardiac surgery
• Scheduled for chest and/or mediastinal chest tube removal in the cardiovascular intensive care unit (CVICU)

Exclusion Criteria:

• Severe chronic lung disease that may impair lung ultrasound interpretation, including:
• Subcutaneous emphysema
• COPD or emphysema with FEV₁ < 50% predicted
• Interstitial lung disease with FEV₁ < 75% predicted
• Documented history of pneumothorax prior to chest tube removal requiring intervention
• Mechanical ventilation at the time of eligibility screening
• Inability to undergo lung ultrasound or chest X-ray (e.g., due to hemodynamic instability or positioning limitations)