BD Plastipakâ„¢ syringes are used for general-purpose injection and aspiration of fluids from vials, ampoules and parts of the body below the surface of the skin. Perfusion syringes, 50ml syringes, are designed for short term use in syringe pumps (active IIa devices) for the administration of pharmaceuticals. The 50 ml Catheter Tip Syringes have a long tapered tip designed to aid in irrigation or for connection to non-ISO compatible Luer connections such as nasogastric tubes.