Urinary tract obstruction is any blockage of urine flow from the kidney to the urethra. Urine backs up above the blockage, causing hydronephrosis (dilated renal pelvis), stasis, infection, and — if prolonged or bilateral — kidney injury. The two most common causes in adults are urinary calculi (stones) and benign prostatic hyperplasia (BPH); others include strictures, tumors, pregnancy, and neurogenic bladder.

Urinary calculi (urolithiasis) form when urine is supersaturated with crystal-forming substances.

General risk factors: dehydration (hot climates, sweating), family history, immobility, obesity, diabetes, some drugs (e.g., topiramate, high-dose vitamin C).

Benign prostatic hyperplasia (BPH) — non-cancerous enlargement of the prostate, common with aging, that compresses the urethra and causes lower urinary tract symptoms (LUTS) and, in some men, acute urinary retention, bladder stones, UTI, and hydronephrosis.

Renal colic (stone moving in the ureter)

• Sudden, severe, colicky flank pain radiating to the groin (labia or testicle); client cannot find a comfortable position and is often restless
• Hematuria (gross or microscopic); nausea and vomiting
• Urgency, frequency, dysuria when the stone is near the bladder
• Fever and chills suggest an infected obstructed kidney — an emergency

BPH

• Storage symptoms: frequency, urgency, nocturia
• Voiding symptoms: hesitancy, weak stream, intermittency, straining, incomplete emptying, post-void dribbling
• Acute urinary retention: inability to void, painful distended bladder (palpable above the pubis)
• Overflow incontinence; recurrent UTI

Signs of kidney involvement: rising creatinine, low urine output, hyperkalemia.

Stones

• Non-contrast CT (low-dose) of abdomen and pelvis — test of choice for suspected stones
• Ultrasound — first choice in pregnancy and children; shows hydronephrosis
• Urinalysis (hematuria, crystals, infection), urine culture; urine pH (low in uric acid stones, high in struvite)
• Serum creatinine, calcium, uric acid, electrolytes
• Stone analysis of any passed or removed stone
• 24-hour urine (volume, calcium, oxalate, citrate, uric acid, sodium) for recurrent formers — for prevention planning, not an emergency step

BPH

• Digital rectal exam — smooth, firm, symmetric enlargement (a hard nodule suggests cancer)
• International Prostate Symptom Score (IPSS); urinalysis; PSA when appropriate
• Post-void residual (PVR) by bladder scanner; uroflowmetry
• Creatinine and ultrasound if kidney involvement is suspected

Report critical findings together in obstruction: rising potassium (dysrhythmia risk), rising creatinine and BUN, and very low urine output each signal AKI and are reported promptly.

Stones

• Pain control first: NSAIDs (e.g., ketorolac) are first-line if kidney function allows — they reduce ureteral spasm; avoid with AKI, GI bleeding, or from 20 weeks of pregnancy; opioids for breakthrough pain (respiratory depression, sedation, constipation); antiemetics
• Observation with hydration for small stones — most stones ≤ 5 mm pass on their own
• Medical expulsive therapy: tamsulosin (alpha blocker) for distal ureteral stones about 5–10 mm — dizziness, orthostatic hypotension, retrograde ejaculation
• Urgent decompression (ureteral stent or percutaneous nephrostomy) for infection with obstruction, AKI, a single kidney, or uncontrolled pain
• Procedures for larger or non-passing stones:
  • Extracorporeal shock wave lithotripsy (ESWL) — shock waves fragment the stone; bruising and hematuria after are expected; not used in pregnancy, uncorrected bleeding disorders, anticoagulant or antiplatelet therapy that cannot be held, or untreated UTI
  • Ureteroscopy with laser lithotripsy, often with a temporary stent
  • Percutaneous nephrolithotomy (PCNL) for large or staghorn stones — nephrostomy tube care, bleeding
• Prevention drugs: thiazide diuretics (calcium stones — hypokalemia, hyperglycemia), potassium citrate (raises urine citrate and pH — first-line for uric acid stones by alkalinizing urine), allopurinol (hyperuricosuria, or uric acid stones when alkalinization is not enough — stop at the first rash)

BPH

• Alpha-1 blockers (tamsulosin, alfuzosin, terazosin, doxazosin) — relax prostate smooth muscle for fast relief. Orthostatic hypotension (especially first dose — take at bedtime), dizziness, retrograde ejaculation; intraoperative floppy iris syndrome — tell the eye surgeon before cataract surgery
• 5-alpha-reductase inhibitors (finasteride, dutasteride) — shrink the prostate over 6 months or more; decreased libido, erectile dysfunction; lower PSA by about half; teratogenic — women who are or may become pregnant should not handle broken or crushed tablets; small increase in high-grade prostate cancer (FDA label); report depression
• PDE-5 inhibitor tadalafil — never with nitrates (severe hypotension); caution with alpha blockers (additive hypotension)
• Surgery: transurethral resection of the prostate (TURP), laser procedures, prostatic urethral lift, open or robotic prostatectomy for very large glands
• Acute retention: bladder catheterization (a coudé-tip catheter may pass the enlarged prostate); suprapubic catheter if urethral insertion fails

Listed in priority order.

1. Assess for infection and sepsis — vital signs, temperature, and mental status first in any client with a stone and fever; an infected obstructed kidney needs urgent drainage and antibiotics
2. Manage pain promptly with prescribed NSAIDs/opioids; reassess; warmth may help
3. Monitor kidney function and output — intake and output, creatinine, potassium; report low output or anuria at once
4. Hydration — oral or IV fluids to maintain good urine flow (unless restricted); do not restrict fluids
5. Strain all urine through gauze or a strainer; save any stone for analysis
6. Encourage ambulation as tolerated — comfortable activity may help passage
7. Nephrostomy and stent care — never clamp or irrigate a nephrostomy unless prescribed; watch for bleeding, leakage, and dislodgement; stent symptoms (flank discomfort on voiding, frequency, mild hematuria) are common
8. Acute urinary retention — catheterize as prescribed; secure the catheter to prevent traction and urethral injury; observe urine color, amount, clarity, and drainage flow; monitor for post-obstructive diuresis (large output) with electrolyte loss
9. After TURP — continuous bladder irrigation (CBI) with isotonic solution through a three-way catheter:
   • Titrate irrigation to keep drainage light pink and free of clots; bright red, thick drainage with clots suggests arterial bleeding — increase flow as per protocol and report
   • If flow stops, check for clots or kinks; irrigate manually per protocol; report
   • True urine output = total drainage − irrigant infused
   • Bladder spasms: common; antispasmodics as prescribed; tell the client not to push or strain against the urge (it is caused by the catheter balloon)
   • Watch for TURP syndrome (dilutional hyponatremia from irrigant absorption during surgery): confusion, nausea, bradycardia, hypertension, seizures
   • Traction on the catheter may be applied briefly for hemostasis — keep leg straight on that side

Stone prevention

• Drink enough fluid to produce at least 2.5 L of urine per day (typically about 3 L of intake), spread through the day and at night; water is best
• Do not restrict dietary calcium — normal calcium intake (about 1,000–1,200 mg/day from food) binds oxalate in the gut and lowers stone risk
• Limit sodium and animal protein
• Calcium oxalate: limit high-oxalate foods (spinach, rhubarb, nuts, beets, chocolate, black tea); avoid high-dose vitamin C supplements
• Uric acid: low-purine diet (limit organ meats, anchovies, sardines, shellfish, beer)
• Treat UTIs promptly (struvite prevention)
• After ESWL: strain urine, expect mild hematuria and bruising, drink fluids, resume normal bathing and activity, report fever or severe pain

BPH and after TURP

• Take alpha blockers at bedtime and rise slowly; avoid driving until the response is known
• Avoid drugs that worsen retention: decongestants (pseudoephedrine), antihistamines, anticholinergics; limit alcohol and caffeine, especially in the evening
• Void when the urge comes; do not hold urine for long; limit fluids 2 hours before bed (not overall)
• After TURP: avoid straining at stool (stool softener, fiber), heavy lifting, vigorous activity, and sexual intercourse for about 4–6 weeks; drink plenty of fluids; temporary dribbling improves with pelvic floor exercises; retrograde ejaculation is common; report bright red bleeding, clots, inability to void, or fever
• Catheter at home: keep it secured, bag below the bladder, tubing free of kinks

• Obstruction with fever — urosepsis; urgent decompression
• Anuria (bilateral obstruction or single kidney) — AKI, hyperkalemia
• Hydronephrosis and loss of kidney function
• Acute urinary retention; bladder rupture (rare); post-obstructive diuresis after relief
• TURP: hemorrhage, clot retention, TURP syndrome, urethral stricture, incontinence
• Recurrent stones (common within 5–10 years without prevention)

• Calcium oxalate stones are most common; struvite = infection (Proteus); uric acid = gout
• Renal colic: sudden severe flank pain to the groin, hematuria, nausea, restlessness
• Non-contrast CT for diagnosis; ultrasound in pregnancy
• Stones ≤ 5 mm usually pass: fluids plus pain control; tamsulosin for expulsion
• Stone + fever = emergency (obstructed infected kidney) — assess vital signs and temperature first
• Strain all urine; save stones for analysis
• Prevention: urine ≥ 2.5 L/day, normal calcium, low sodium and animal protein
• BPH: hesitancy, weak stream, nocturia, incomplete emptying; alpha blockers → orthostatic hypotension (rise slowly); finasteride → shrinks prostate, halves PSA, teratogenic
• Avoid decongestants and antihistamines in BPH (retention)
• Retention: catheterize and secure the catheter; monitor for post-obstructive diuresis
• After TURP: CBI to keep drainage light pink; output = drainage − irrigant; no straining or heavy lifting