To the Editor:-Intravenous catheters occasionally obstruct because of blood clots or kinking of the catheter. We experienced a case of intravenous catheter obstruction caused by a cored fragment of a medication vial stopper.

A patient had a 20-gauge, 1-inch intravenous catheter placed in the dorsum of the hand. An intravenous induction of anesthesia was uneventful. Thirty minutes into the procedure (near the end of the surgery), observation of the drip chamber showed that the gravity-driven infusion had ceased. All attempts at restarting the infusion by gentle aspiration or flushing solution through the ports failed. When the intravenous catheter was later removed, a small gray fragment was seen occluding the catheter. The fragment was removed from the catheter. It was roughly spherical, measured about 1 mm in diameter, and was similar in consistency and color to the stopper of the succinylcholine used during induction of anesthesia.

We believe that the fragment was a small piece of the stopper of a medication vial. The medications were drawn into syringes using the Monoject 18-gauge, 1-inch blunt cannulas (Sherwood Medical, St. Louis, MO). The blunt cannulas and Lifeshield IV sets (Abbott Laboratories, North Chicago, IL) decrease the use of sharps and their hazards. However, when used with standard vials, the blunt cannula can core out a small piece of rubber that can then be aspirated into the syringe. The package instructions on the box of blunt cannulas state “use only with pierced IV reseals.” This complication may be avoided by using sharp needles to aspirate medication from vials or by using the Abbott Lifeshield vial adapter to access the vial's contents with a blunt cannula.

Bradley A. Stone, M.D.

Brad Leon, C.R.N.A.

St. Joseph's Hospital; Asheville, North Carolina;