Urinary bladder is a part of human urinary system. It is a muscular sac, a holding tank for the waste fluid ‘Urine’ that leaves from the kidney. The average bladder is capable of holding between 400 to 500 ml of urine without over distension. Once it crosses this limit, this muscular sac tries to distend so as to accommodate the extra urine that flows in.
A point comes when the bladder becomes over distended and there is no capacity left to store urine. In a thin person, distended bladder can be easily elicited as a swelling in the lower abdomen.
Urination is partly a reflex and partly a voluntary act. Once the urine begins to fill up in the bladder, the sensory receptors of bladder become active and trigger a reflex action producing an urge to pass urine. However, since it is partly controlled voluntarily, the urinary sphincter will only relax when the person whishes or finds adequate place to void urine. So in this case, a distended bladder results without any pathological involvement.
However, there are circumstances and pathological conditions where a person may not be able to pass urine or pass very minimum quantity even if there is an urge.
Causes Of Distended Urinary Bladder
Primarily there are two causes that can lead to retention of urine and subsequently bladder distension. It can be;
- Due to an obstruction in the urethra or the at the bladder neck region from where the urine has to pass out.
- Damage to the muscle wall of the bladder or to the nerves which control urination.
Following are the causes:
Genitourinary causes:
- Stone or a growth in the bladder. A large stone or a growth (benign or malignant) in bladder can block the passage of urine flow giving rise to bladder distension.
- A stone, foreign body, stricture spasm of urethral sphincter, infection or an ulcer in urethra can cause complete or partial blockage of urine flow.
- Prostate enlargement also called benign prostatic hypertrophy (BPH) is a common problem faced by many elderly male above the age of 60. The enlarged prostate block the passage of urine flow either completely or partially.
- Problem of uterus in females: fibroids, ovarian cysts, carcinoma of cervix, abnormal position of uterus can compress the bladder neck and obstruct urinary flow.
- Phimosis in males. It is common in infancy.
Neurological causes:
- Spinal cord disease: transverse myelitis, dislocation of spine, fracture of spine due to trauma, tuberculosis of spine causing compression of nerves.
- Stroke.
- Multiple sclerosis.
Drugs:
- Smooth muscle relaxants.
- Certain Antiasthma tic drugs.
- Anesthetic drugs.
- Anticholinergic drugs.
In most cases when the action of drugs is diminished, the retention is relieved.
Other causes include postoperative urinary retention and bladder distension, rectum and growth in pelvic area, tetanus etc.
Hysterical causes may rarely occur, but the organic causes must be rule out before this diagnosis is established.
Symptoms Of Distended Bladder
The patient has the history of inability to pass urine since few hours even if there is an urge to do so. There is obvious swelling in the lower abdomen caused as a result of full bladder which is prominently seen in thin person. The area of distended bladder is tender when touched. The patient may have mild to moderate pain in the lower abdomen, but in chronic retention the distension of bladder is painless.
Burning of urination, straining during urination, hesitancy, thin urine stream may be present for a long time before the onset of retention of urine and consequent distention of bladder.
In neurological causes there would be other neurological symptoms like tingling and pin and needle sensation in limbs, weakness of muscles, alteration in tone and power of the muscles.
Partial leakage of urine also called ‘retention overflow’ occurs when the patient has no control of his urine. Small amount of urine overflows from distended bladder after some time. It occurs generally when retention of urine is left unattended.
Treatment For Distended Bladder
- The patient must be reassured and encouraged to pass urine.
- At the same time, the cause for retention and bladder distention should be found and treated.
- If all the sensations are normal, the patient may be advised to sit in a bathtub containing warm water for some time. It will allow reducing the internal congestion. Usually this is the most effective home remedy for such patients.
- Sometime when a child is made to stand in front of a running tap water, he easily passes urine.
- If the home remedies fail, it is essential to go to a hospital or consult your doctor. In the hospital catheterization is possible which is done with full aseptic precautions. If the catheter has to be retained, a self retaining catheter like Foley’s catheter may be used.