Acute Urinary Retention

Acute urinary retention is sudden inability to pass urine.  It is a painful condition.

Causes:

a)  Mechanical

  • Urinary Bladder:- Stones, tumors and stricture of the bladder neck.
  • Urethra:- Urethral stricture, rupture, foreign body, stone and growth.
  • Prostate:- Prostatic abscess, BPH, CA.

b) Miscellaneous:  Post operative retention, hysteria, drugs such as anticholinergics, smooth muscle relaxants, pregnancy (retroverted gravid uterus), spinal anaesthesia, fecal impaction, anal pain (after haemorrhoidectomy).

Clinical Features

Clinical features of acute retention of urine:

  • No urine passed for several hours.
  • The bladder may be visible, tense and tender to palpation and dull to percussion.
  • Rarely, a prolapsed lumbar disc causing a cauda equina lesion will be the cause.  This is excluded by checking the reflexes in the lower limb and perianal sensations

Treatment

  • If there is postoperative retention, ask the patient to go to the toilet and try to pass urine.  If the patient does not succeed, he or she is sedated and is asked to sit in warm water.
  • In rest of the conditions, the correct treatment is to pass a fine urethral catheter (14 FG) and drain the bladder. (French gauge is defined as the external circumference of the catheter and dividing it by 3 gives the outside diameter in mm).  Further investigations and management are then planned.
  • Urethral catheter should be passed under full aseptic technique.  In the male if the catheter will not pass into the bladder, it is usually due to poor technique, lack of adequate anaesthesia, traumatization of the urethra or because of a urethral stricture.
  • Force should not be used while passing catheter.
  • If after a reasonable attempt with catheterisation, the bladder has not been entered, suprapubic puncture with a lumbar puncture needle or an AbbocathR is a useful method of relieving acute retention.
  • A catheter is placed in the bladder under direct vision through a small incision under local anaesthesia.
  • Whenever the bladder is catheterized for urinary retention, it is important to record the volume drained and to examine the patient’s abdomen a few minutes later to exclude some other intraabdominal causes.