Fluid collection sets, catheters, and intravenous infusion sets are typically used to collect bodily fluids from a patient or to infuse liquids into a patient. These devices typically include a length of flexible plastic tubing with a proximal end connected to a plastic fitting and a distal end connected to a needle, or in the case of a catheter, a tubular assembly. In practice, fluid is transferred via the plastic tubing either to or from the needle or tubular assembly.
Accidental sticks with a needle cannula can be not only painful but can also transmit disease from a patient to medical personnel. Similarly, catheters may retain fluids when they are removed from a patient and transmit disease via these fluids if passed to medical personnel. As a result, nearly all needle assemblies and other sharp medical implements are employed with an apparatus for enclosing the sharp tip of the needle or tubular assembly both prior to and after use.