6.9 Proportional Assist Ventilation

Proportional Assist Ventilation (PAV) is another ventilation mode that relies on the patient’s ability to initiate breaths. With this approach, support provided by the ventilator is adapted according to the patient’s effort. The clinician establishes the level of assistance (ranging from [latex]5\%[/latex] to [latex]95\%[/latex]) that the ventilator will provide. This assistance represents the work performed by the ventilator.

During PAV, the patient’s generated flow and pressure are continuously measured and assistance is provided in proportion to their effort. Additionally, lung mechanics, such as resistance and compliance, are monitored and taken into account when delivering support. The ventilator employs an algorithm based on the equation of motion to calculate the appropriate pressure required for assistance.