Weaning from Controlled Ventilation and Supplemental Oxygen

Weaning from Intermittent Positive-Pressure Ventilation Criteria THE criteria for the discontinuation of controlled ventilation are the converse of those for the institution of controlled ventilation. The patient should have an alveolar arterial oxygen tension difference measured breathing 100 per cent oxygen (Aa DO₂^1.0) of less than 300 to 350 mm Hg.¹ A minimum vital capacity of 10 to 15 ml per kilogram of body weight is necessary. The maximum inspiratory force should be numerically greater than -20 cm of water.² The ratio of dead space to tidal volume (VD/VT) is an accurate measure of whether a patient will.