Hypophosphatemia as a reversible cause of refractory ventilatory failure.

An 81-yr-old male with pulmonary emphysema was hospitalized because of malnutrition and hypoglycemia. This patient developed ventilatory failure requiring mechanical assistance 12 h after initiation of iv hyperalimentation. Severe hypophosphatemia (0.1 mg/dl), mild hypocalcemia, hypomagnesemia, and hypokalemia were subsequently and concomitantly documented. Repeated attempts to wean him from the respirator failed until hypophosphatemia was corrected. When difficulties are encountered in weaning patients from mechanical ventilation, attention should be directed toward detection of hypophosphatemia. This may be crucial in the presence of chronic lung disease.