A distended bladder is an abnormally swollen bladder caused by retained urine. This occurs when the bladder cannot empty completely, leaving an excessive volume inside. It is a serious medical condition requiring prompt attention.
Understanding Normal Bladder Function
A healthy bladder functions as a temporary storage organ for urine, capable of holding a significant volume before signaling the need to void. As urine fills, stretch receptors send signals to the brain, indicating fullness. This allows conscious control over urination. During urination, the detrusor muscle contracts, while sphincter muscles relax, allowing urine to flow out completely through the urethra.
Physical Blockages to Urine Flow
Physical obstructions within the urinary tract commonly impede urine flow, leading to bladder distension. An enlarged prostate (BPH) is a frequent cause in men, where the prostate gland compresses the urethra, restricting urine passage. Bladder stones, formed from crystallized minerals, can also obstruct the bladder outlet or urethra.
Urethral strictures, narrowings of the urethra, often result from injury, infection, or inflammation, significantly impeding urine flow. These strictures make it difficult for the bladder to empty effectively. Tumors within the bladder or nearby pelvic organs can physically compress the urethra or bladder neck, obstructing urine outflow and leading to retention.
Nerve Damage and Medication Effects
Damage to the nerves controlling bladder function can disrupt its ability to empty, causing distension. Conditions like diabetes, stroke, spinal cord injury, multiple sclerosis, or Parkinson’s disease can impair nerve signals between the brain and bladder. This prevents the brain from receiving fullness signals or sending commands for the detrusor muscle to contract and expel urine.
Certain medications can also interfere with normal bladder muscle contraction or nerve impulses, leading to urinary retention. Antihistamines and decongestants can relax the bladder muscle or tighten the bladder neck, making urination difficult. Anticholinergic drugs, used for conditions like overactive bladder or depression, can block nerve signals that stimulate bladder contraction. Opioids can also reduce the bladder’s ability to contract effectively and relax the sphincter.
Other Contributing Factors
Beyond common blockages and nerve issues, other factors can contribute to bladder distension. Post-surgical urinary retention is a recognized complication, particularly following pelvic or abdominal surgeries. Anesthesia, pain medications, and tissue manipulation during an operation can temporarily impair bladder function. This impairment often resolves as anesthesia effects wear off and the body recovers.
Chronic overstretching of the bladder, often due to consistently delaying urination, can weaken the detrusor muscles. When the bladder is frequently allowed to become excessively full, the muscle fibers can lose their elasticity and ability to contract forcefully. This diminished contractile strength impairs the bladder’s efficiency in expelling urine, leading to incomplete emptying and eventual distension.
When to Seek Medical Help
Recognizing the signs of a distended bladder and seeking prompt medical attention is important due to its serious nature. Key symptoms include inability to urinate despite a strong urge, severe lower abdominal pain or discomfort, and a noticeable swelling or lump in the lower abdomen. Individuals may also experience a persistent feeling of fullness even after attempting to urinate. These indicators suggest acute urinary retention, a medical emergency requiring immediate evaluation and intervention.
References
1. Chronic Urinary Retention: A Review of the Literature. [https://vertexaisearch.googleapis.com/v1/projects/106367733261/locations/us-central1/dataStores/7666324269146112000/documents/5196328352664798208:search?query=causes%20of%20bladder%20distension%20enlarged%20prostate&_additional_parameters=%7B%22data_store_location%22:%22us-central1%22%7D]
2. Acute Urinary Retention. [https://vertexaisearch.googleapis.com/v1/projects/106367733261/locations/us-central1/dataStores/7666324269146112000/documents/1367784334338575973:search?query=bladder%20stones%20cause%20urinary%20retention&_additional_parameters=%7B%22data_store_location%22:%22us-central1%22%7D]
3. Urinary Retention. [https://vertexaisearch.googleapis.com/v1/projects/106367733261/locations/us-central1/dataStores/7666324269146112000/documents/5732943793755355048:search?query=nerve%20damage%20bladder%20dysfunction%20causes&_additional_parameters=%7B%22data_store_location%22:%22us-central1%22%7D]
4. Postoperative Urinary Retention. [https://vertexaisearch.googleapis.com/v1/projects/106367733261/locations/us-central1/dataStores/7666324269146112000/documents/5555437177570498304:search?query=post-surgical%20urinary%20retention%20causes&_additional_parameters=%7B%22data_store_location%22:%22us-central1%22%7D]