Blood Pressure Monitoring Accuracy in Patients Undergoing Lung Surgery With One-Lung Ventilation Using an Arm Cuff and Arterial Line

This study will test how accurate a blood pressure cuff is during a specific type of chest surgery.

In some lung surgeries, doctors use a method called video-assisted thoracoscopic surgery (VATS), where small tools and a camera are inserted through the chest wall. During these procedures, patients often have only one lung ventilated to give the surgeon more space to work. This setup can affect how well a blood pressure cuff on the arm reflects the true blood pressure inside the body.

This study will compare readings from the arm cuff (non-invasive) with those from a thin tube placed inside an artery (invasive), which is more accurate but also more uncomfortable and carries some risks.

Researchers will use a method called error grid analysis to see how closely the cuff readings match the invasive ones. They want to find out if the cuff is accurate enough to be used safely in these surgeries. If it is, patients might not need an invasive line as often in the future.

People 18 years or older who are already going to have invasive blood pressure monitoring during planned thoracic surgery with one-lung ventilation may be able to join the study. The research team will collect blood pressure measurements about every 20 minutes during surgery, as well as basic information like age, weight, and what medications are given.