Subject(s)
Hypercapnia , Hypoxia , Noninvasive Ventilation , Respiratory Insufficiency/therapy , Contraindications, Procedure , Humans , Hypercapnia/diagnosis , Hypercapnia/etiology , Hypercapnia/therapy , Hypoxia/diagnosis , Hypoxia/etiology , Hypoxia/therapy , Noninvasive Ventilation/adverse effects , Noninvasive Ventilation/methods , Noninvasive Ventilation/standards , Patient Care Management/methods , Patient Care Management/standards , Patient Selection , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/physiopathology , Respiratory Insufficiency/blood , Respiratory Insufficiency/etiologyABSTRACT
A 69-year-old male was referred from the renal unit to radiology for investigation of bleeding per rectum. A CT mesenteric angiogram was performed. However, it was noted on the pre-contrast images that the large bowel contained positive oral contrast media. The procedure was abandoned as it would have been difficult to see extravasation of intravenous contrast from a bleeding point in the large bowel. The initial belief was that either the patient had been given oral contrast by ward staff on the assumption that it would be needed, or had had a recent radiological study requiring contrast, which was still present. Neither was the case; it emerged that the patient was taking Fosrenol (Shire Pharmaceuticals, Wayne, PA), a lanthanum carbonate medication used in the treatment of hyperphosphataemia. Lanthanum is densely radio-opaque and appears as positive bowel contrast on CT and plain radiography studies. When considering radiological studies specifically requiring the absence of oral contrast, it is important to be aware of the patient's drug history to avoid non-diagnostic scans with the associated radiation exposure.
