Hypophosphatemia as a cause of failed weaning: the importance of metabolic factors.

Hypophosphatemia has been only occasionally implicated as the cause of respiratory failure. This report illustrates its pathogenetic importance in the maintenance of such condition, as well as the importance of obtaining and maintaining normal values of the serum phosphorus level to achieve successful weaning. The relationship between maximum inspiratory pressure and the patient's inorganic phosphate level is presented (r = .97; p less than .01).