Misplacement of central venous pressure catheters and unilateral pulmonary edema.

Two instances of misplacement of a central venous pressure monitoring catheter into a pulmonary artery are presented. In one case, reported in detail, unilateral pulmonary edema developed during administration of 0.5N saline for the treatment of diabetic acidosis via the misplaced catheter, and it reverted following repositioning of the catheter in the superior vena caca. Experiments were carried out in dogs to explore possible causes of this phenomenon. The results of these experiments suggest that the release of vasoactive substances, stimulation of neural reflexes, or both are the pathophysiological mechanisms responsible for the development of the pulmonary edema.