Abstract: A dual-lumen fistula needle for use in hemodialysis treatment. The needle has a gently tapered neck and is divided into arterial and venous lumens by a center septum which is bonded in place. The septum is formed so that the lumens have substantially equal cross sections substantially throughout the length of the needle to promote equal flow rates in the lumens. The diameter of the needle at the tip is similar to that of single-lumen needles in order to reduce discomfort on insertion.

Abstract: A double lumen catheter having a fluid intake lumen and fluid return lumen of equal cross-sectional area, separated by an internal divide wherein blood flow characteristics are increased and maintained in a continuous fashion by a series of apertures positioned on both the intake side and return side of the catheter is disclosed. The apertures are in such position and configuration that they communicate with one another to prevent the accumulation of fibrin or other matter within the lumens as fluid enters into or exits from those lumens.

Abstract: A medical electrode and skin preparation device is adapted to be secured to the skin and is designed to prepare the skin by penetration of the epidermal layer of the skin in contact with the electrical conductor of the electrode after the electrode is secured in place on the skin. The electrode includes abrading member associated with electrical conductor capable of transmitting biopotential events for recording, with the electrical conductor retained by a collar and adhesive-coated pad securing the electrode to the skin of the patient. The abrading member in contact with the skin is movable relative to the skin of the patient and collar by an applicator gun to penetrate the epidermal layer of skin after the electrode is placed on the skin. Uniform skin preparation achieved by the electrode and applicator gun minimizes motion artifacts arising from skin potential variations.