Patient Self Inflicted Lung Injury (PSILI) is a relatively new concept within mechanical ventilation. It implies that a patient can cause harm to their own lungs, creating barotrauma due to excessive transpulmonary pressure as a result of increased patient respiratory effort.
In Pressure Support mechanical ventilation it's not always easy to identify patients at risk of PSILI. This page will attempt to show you how.
Intensivist Dr. Bertoni proposed a method to estimate respiratory effort: he proposed that by performing an expiratory hold and determining the nadir of the pressure curve, you could determine the force that the patient is applying to the ventilator in order to receive an inspiration, i.e. the predicted muscular pressure or Pmus. Despite seemingly adequate respiratory support by the ventilator, some patients still show signs of increased respiratory effort. The predicted force applied specifically to the lungs, i.e. the predicted transpulmonary pressure or Ptp, is derived from this as well.
How to perform the measurement
- Press record on your ventilator
- Perform an expiratory hold
