What is the purpose of the Positive Pressure Release Valve in a chest drainage system?

• A. Safeguard against tension pneumothorax by releasing accumulating positive pressure
• B. Regulate drainage volume
• C. Filter the drainage fluid
• D. Increase suction pressure

Answer: (A)

The Positive Pressure Release Valve acts as a safety feature to prevent dangerous buildup of air pressure in the pleural space. If intrapleural pressure rises above a safe level—such as during coughing, Valsalva maneuvers, or an air leak—the valve opens and vents air to the atmosphere, protecting against tension pneumothorax. This function is about releasing excess positive pressure, not regulating how much fluid drains, filtering drainage, or increasing suction. The valve closes again once pressure drops to a safe level, allowing normal drainage to continue.