FIBRIN SHEET COVERING SUBCLAVIAN OR FEMORAL DIALYSIS CATHETERS

The existence of a sheet around a single lumen dialysis catheter tip, which provokes a valve mechanism, is proved by the observation that se veral times during the replacement procedure of a dialysis catheter, a sheet surrounding the surface of the catheter is removed with the dia lysis catheter. This sheet is grey, approximately 1 mm thick and 30 mm long and consists of fibrin and thrombocytes. Bacteriological examina tions were always negative. The existence of the sheet in vivo is demo nstrated by digitalized angiography during the removal procedure for s ingle lumen dialysis catheters. Rarely, only the sheet is removed with the catheter. In all other instances, the sheet is stripped off and r emains in the subcutaneous tunnel or in the vascular bed without causi ng much clinical discomfort in most patients. Occasionally an episode of cough, dyspnea, hypotension, retrosternal oppression or hemoptae af ter removing the single lumen dialysis catheter, suggest pulmonary emb olism or lung infarction.