Proportional Assist Ventilation (PAV): Physiologic Rationale and Clinical Advantages

  • M. Ranieri
  • S. Grasso
  • L. Mascia
  • R. Giuliani


Considerable interest has recently developed in pressure-assisted methods of ventilatory support. Two of these have been so far described, pressure support ventilation (PSV) (1,2) and the more recent proportional assist ventilation (PAV) (3, 4). The intent of these methods is to assist each spontaneous breath by providing positive pressure at the airway (Paw) during the period of spontaneous inspiration. During PSV and PAV, Paw is the ventilator controlled variable while inspiratory flow and tidal volume are determined by the combined action of the pressure generated by the respiratory muscles (Pmus) the pressure generated by the ventilator (Pappl). Because the ventilatory consequences of these methods are essentially the result of patient-ventilator interaction, the patient retains considerable control over breathing pattern, flow pattern and ventilation, and this is expected to result in greater patient comfort (5).


Dead Space Pressure Support Ventilation Inspiratory Flow Ventilatory Requirement Piston Chamber 
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Copyright information

© Springer-Verlag Italia, Milano 1996

Authors and Affiliations

  • M. Ranieri
  • S. Grasso
  • L. Mascia
  • R. Giuliani

There are no affiliations available

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