Transpulmonary pressure

Transpulmonary pressure is the difference in pressure between the alveolar pressure and the intrapleural pressure in the pleural cavity. It is a measure of the lung's tendency to collapse, or the force that keeps the lung open.

Overview

During normal respiration, the transpulmonary pressure is positive, meaning that the alveolar pressure is greater than the intrapleural pressure. This is what keeps the lungs inflated. If the transpulmonary pressure becomes negative, the lungs would collapse.

Measurement

Transpulmonary pressure can be measured using an esophageal balloon, which estimates the intrapleural pressure, and a manometer, which measures the alveolar pressure. The difference between these two measurements is the transpulmonary pressure.

Clinical significance

In mechanical ventilation, monitoring of the transpulmonary pressure can help to prevent ventilator-induced lung injury by ensuring that the pressure used does not exceed the lung's capacity to expand. It can also be used to guide the setting of the ventilator in patients with acute respiratory distress syndrome.

See also

• Pulmonary alveolus
• Pleural cavity
• Mechanical ventilation
• Acute respiratory distress syndrome