- normally an inspiratory to expiratory time ratio (I/E) of 1:2 is used - inverse I/E is also utilized in ARDS to prevent barotrauma - long sustained inspiration reduces mean airway pressure while increasing the PaO2 for a given FiO2; - despite the benefits in gas exchange, the prolonged inspiratory duration relative to expiration is uncomfortable for the alert patient, and paralysis may be required; - if
PIP are high, one way to reduce them is to reduce the inspiratory flow
rate and prolong the inspiratory time (beware of auto
PEEP) - intermittent positive pressure ventilation with inspiratory time longer than expiratory time (inverse ratio ventilation) has been successfully to treat infants with ARDS;
