An innovative intravenous catheter is described. The inventive catheter comprises an introduction needle, a cannula portion having one or more slots, through which the introduction needle extends when deployed, an in-dwelling check valve, a needle retraction mechanism, and a safety enclosure to contain the introduction needle when retracted. The in-dwelling check valve may further allow a needle from syringe or intravenous drip to be inserted from the rear end of the check valve and extend into the flash chamber to introduce other fluids, and function as a second fluid line. The one or more slots disposed along the cannula wall and may extend at least a portion of the length of the cannula portion, and function as to increase blood flow into the catheter, reducing the pressure required to flow blood into the catheter. The introduction needle may be caused to retract into a safety enclosure affixed to the inventive catheter.
