To the Editor.
—The article entitled "Dialysis Catheter-Induced Pericardial Tamponade," by Merrill and Raab, published in the September Archives (1982;142:1751-1753), discussed the practical difficulties associated with confirming the exact location of the tip of a subclavian (hemodialysis) catheter introduced percutaneously. In this case, with a fatal outcome, the tip of the catheter (with end and side-holes) was in the pericardial sac. Resultant tamponade caused by plasmapheresis led to hypotension and cardiac arrest. Neither the abnormal location of the catheter tip nor the subsequent outcome, pericardial infusion with resultant cardiac tamponade, was recognized during the terminal course of this patient.In a critically ill patient, with a rapidly changing stormy course, any procedure to locate exactly the tip of a central venous catheter is cumbersome and time-consuming. As discussed by the authors, attachment of a pressure transducer to the catheter may indicate entrance within the cardiac chambers. Contrast injection within the