Proportional assist ventilation (PAV) is an advanced and newer mode of ventilation that helps in adjusting the airway pressure according to patient's needs unlike the older methods where the predetermined tidal pressure was provided. If the patient uses more effort in breathing, the pressure generated by the ventilator is increased and with less effort the pressure is decreased. It is a synchronized ventilator mode that provides the patient with the desired inspiratory pressure by making use of the patient's inspiratory effort, in other words this ventilation mode allows the patient to accomplish the pattern of breathing that is best suited for him. It helps in reducing the overall breathing work of the patient, helps in weaning and decrease muscle dysfunction