Measurement of pressure-volume curves in patients on mechanical ventilation. Methods and significance.

In critically ill patients measurements of pressure volume curves has been suggested as a method for assessing the severity of lung injury and for monitoring the evolution of the lung disease; it can also guide the ventilatory adjustments to optimize the mechanical ventilation. The static pressure-volume curves are impaired in acute respiratory distress syndrome (ARDS). The evaluation of the lower and upper inflection point on the pressure-volumes curves at the bedside of patients with acute respiratory failure means to apply a "protective ventilatory strategy". The combined application of positive end expiratory pressure (PEEP) to the level of alveolar recruitment and low tidal volume (< 6 ml/kg) ameliorates the lung function and decrease mortality in ARDS patients. Routine monitoring with continuous technique is easy and develops good therapeutic practice.