The introduction of polyethylene catheters for intravenous use by Meyers in 1945 has been a major contribution to patient care. Within recent years however there has been a mounting number of reports warning of the hazards associated with their use. Especially, embolism of an intravenous polyethylene catheter is the most serious complication. The authors had experience with a case of catheter embolism from subclavian catheterization for monitoring of central venoas pressure and rapid transfusion or fluid infusion. The case, a woman with ectopie pregnancy, in extreme shock, was operated on with serious risk of catheter embolism. Vital signs were stable during the operation. When the patient recovered from the anesthesia she suffered a sudden onset of chest pain and slight dyspnea for 10- minutes in the recovery room. Due to the fact that the embolus could not be seen by X-Ray, operation for removal of the catheter embolus was not performed. The patient's condition was good during the hospital stay and at discharge, and no trouble has been noted during 9 months follow-up.