Abstract: A catheterization apparatus is provided having a catheter, a drainage hose, and a collection vessel. The catheter is of the endwelling type having a retention balloon for expansion while the head of the catheter is in the bladder or other cavity being drained thereby. The balloon when expanded comprises a plurality of wings or loops which function in cooperation with at least one aperture which communicates the interior bore or lumen of the catheter with the bladder such that the bladder cannot collapse about and occlude the aperture. In this manner, substantially little or no residual urine remains in the bladder during catheterization thereof, thus reducing significantly growth of bacteria within the bladder which would tend to cause a urinary tract infection. The catheter, hose, and vessel normally form a sealed system which is preferably only broken every 24 hours. The vessel is sized so as to accept at least a 24 hour output of urine and is preferably nonreusable.