A patient’s urine extravasates if he tries to pass it through a ruptured urethra. Try to prevent this happening by draining his bladder. In injuries B, C, and D, in Fig. 68-1, combine this with draining his prevesical space. Extravasation can also complicate a urethral stricture (23.10).
Extravasation can be superficial or deep. Superficial extravasation appears as a large, expanding, tender swelling of the patient’s penis, or a swelling in his scrotum, perineum, or lower abdomen. Provided he has not been catheterized, the urine which has escaped is unlikely to be infected. If it is infected, severe necrotizing cellulitis will follow.
If a patient presents late with a large red oedematous swelling, insert a suprapubic catheter into his bladder (23.6), and let out the stinking fluid through multiple wide incisions in the swelling. Give him antibiotics (2.7) and wait. This is not the time to start repairing his urethra. If you cannot refer him, you can try the residual urine regime (68.3) after a month or so of suprapubic drainage. If he has only a little residual urine, try bouginage. If that is satisfactory, remove his suprapubic catheter when his residual urine is less than 75 ml. If the overlying skin sloughs, graft his wound.