Urolithiasis (Renal Calculi) Nursing Management & Interventions

Kidney stones bring some of the worst pain you will see, and the priorities are simple: control the pain, keep the kidney working, move the stone, and prevent the next one. Strain every drop of urine, push fluids, and watch for the infection or obstruction that turns a stone into an emergency.

What Is Urolithiasis?

Urolithiasis means stones (calculi) in the urinary tract. Stones form when the urinary concentration of substances such as calcium oxalate, calcium phosphate, and uric acid rises. They range from minute granular deposits to the size of an orange. Infection, urinary stasis, and immobility all favor stone formation by slowing renal drainage and altering calcium metabolism. The problem occurs predominantly in the third to fifth decades and affects men more often than women.

Pathophysiology

Stones can sit anywhere in the urinary tract but are most common in the renal pelvis and calyces. Stones forming in the kidney are nephrolithiasis; those formed in the ureters are ureterolithiasis. They may be single or multiple, ranging from a grain of salt to a pebble or a staghorn calculus. Composition is predominantly calcium oxalate and calcium phosphate, with uric acid, struvite, and cystine also forming stones.

Etiology

Slow urine flow lets crystals accumulate, damaging the lining of the urinary tract and reducing the inhibitor substances that would prevent crystal buildup. Stones may stay asymptomatic until they pass into a ureter or obstruct urine flow, the point at which the risk of renal damage is acute and pain peaks. Causes include dehydration; heredity; excessive intake of vitamins C and D, grapefruit juice, and purines (gout); congenital renal abnormalities; and some medications, such as acetazolamide (Diamox) or indinavir (Crixivan).

Clinical Manifestations

Manifestations depend on obstruction, infection, and edema, ranging from mild to excruciating pain.

Stones in renal pelvis: intense, deep ache in the costovertebral region; hematuria and pyuria; pain radiating anteriorly and downward toward the bladder in females and toward the testes in males; acute pain, nausea, vomiting, and costovertebral tenderness (renal colic); abdominal discomfort and diarrhea.

Ureteral colic (stones lodged in ureter): acute, excruciating, colicky, wavelike pain radiating down the thigh to the genitalia; frequent desire to void with little urine passed, usually containing blood from the abrasive action of the stone.

Stones lodged in bladder: irritation symptoms associated with urinary tract infection and hematuria; urinary retention if the stone obstructs the bladder neck; possible urosepsis if infection is present.

Assessment and Diagnostic Methods

Diagnosis is confirmed by x-rays of the kidneys, ureters, and bladder (KUB) or by ultrasonography, IV urography, or retrograde pyelography. Blood chemistries and a 24-hour urine test measure calcium, uric acid, creatinine, sodium, pH, and total volume. Chemical analysis determines stone composition.

Diagnostic Studies

• Urinalysis: Color may be yellow, dark brown, or bloody. Commonly shows RBCs, WBCs, crystals (cystine, uric acid, calcium oxalate), casts, minerals, bacteria, and pus; pH may be less than 5 (promotes cystine and uric acid stones) or higher than 7.5 (promotes magnesium, struvite, phosphate, or calcium phosphate stones).
• Urine (24-hr): Cr, uric acid, calcium, phosphorus, oxalate, or cystine may be elevated.
• Urine culture: May reveal UTI (Staphylococcus aureus, Proteus, Klebsiella, Pseudomonas).
• Biochemical survey: Elevated magnesium, calcium, uric acid, phosphates, protein, electrolytes.
• Serum and urine BUN/Cr: Abnormal (high in serum, low in urine) from a high obstructive stone causing ischemia or necrosis.
• Serum chloride and bicarbonate: Elevated chloride with decreased bicarbonate suggests developing renal tubular acidosis.
• CBC: Hb/Hct abnormal if the patient is severely dehydrated, polycythemic (encourages precipitation of solids), or anemic (hemorrhage, kidney dysfunction or failure); RBCs usually normal; WBCs may be increased, indicating infection or septicemia.
• Parathyroid hormone (PTH): May be increased if kidney failure is present (PTH stimulates reabsorption of calcium from bone, raising serum and urine calcium).
• KUB x-ray: Shows calculi and anatomical changes around the kidneys or along the ureter.
• IVP: Rapidly confirms urolithiasis as a cause of abdominal or flank pain; shows anatomical abnormalities (distended ureter) and outlines calculi.
• Cystoureteroscopy: Direct visualization of bladder and ureter may reveal the stone and obstructive effects.
• CT scan: Identifies and delineates calculi and other masses, plus kidney, ureteral, and bladder distension.
• Ultrasound of kidney: Determines obstructive changes and stone location without the risk of contrast-induced failure.

Nursing Priorities

1. Alleviate pain.
2. Maintain adequate renal functioning.
3. Prevent complications.
4. Provide information about the disease process, prognosis, and treatment needs.

Medical Management

The goals are to eradicate the stone, determine its type, prevent nephron destruction, control infection, and relieve any obstruction.

Pharmacologic and Nutritional Therapy

Give opioid analgesics (to prevent shock and syncope) and NSAIDs. Increase fluid intake to help the stone pass unless the patient is vomiting; patients with renal stones should drink eight to ten 8 oz glasses of water daily or receive IV fluids to keep urine dilute. For calcium stones: reduce dietary protein and sodium, push fluids, and acidify urine with agents such as ammonium chloride and thiazide diuretics if parathormone production is increased. For uric stones: low-purine, limited-protein diet plus allopurinol (Zyloprim). For cystine stones: low-protein diet, alkalinization of urine, and increased fluids. For oxalate stones: dilute urine and limited oxalate intake (spinach, strawberries, rhubarb, chocolate, tea, peanuts, wheat bran).

Stone Removal Procedures

Ureteroscopy fragments stones with laser, electrohydraulic lithotripsy, or ultrasound, then removes them. Other options are extracorporeal shock wave lithotripsy (ESWL), percutaneous nephrostomy and endourologic methods, electrohydraulic lithotripsy, and chemolysis (stone dissolution) for poor surgical risks, those who refuse other methods, or easily dissolved struvite stones. Surgical removal is performed in only 1% to 2% of patients.

Nursing Process

Assessment

Assess the severity, location, and radiation of pain and associated nausea, vomiting, diarrhea, and abdominal distention. Watch for signs of urinary tract infection (chills, fever, frequency, hesitancy) and obstruction (frequent voiding of small amounts, oliguria, or anuria). Observe urine for blood and strain it for stones or gravel. Focus the history on factors that predispose to stones or that may have precipitated this episode of renal or ureteral colic, and assess the patient's knowledge of stones and recurrence prevention.

Diagnosis

Nursing diagnoses: acute pain related to inflammation, obstruction, and abrasion of the urinary tract; deficient knowledge regarding prevention of recurrence.

Collaborative problems and potential complications: infection and urosepsis (from UTI and pyelonephritis); obstruction of the urinary tract by stone or edema, with subsequent acute renal failure.

Planning and Goals

Major goals include relief of pain and discomfort, prevention of recurrence, and absence of complications.

Nursing Interventions

Relieving pain. Give opioid analgesics (IV or intramuscular) with IV NSAID as prescribed. Help the patient into a position of comfort and assist ambulation for some relief. Monitor pain closely and report any increase in severity promptly.

Monitoring and managing complications. Encourage increased fluids and ambulation, starting IV fluids if oral intake is inadequate. Monitor total urine output and voiding patterns. Encourage ambulation to move the stone through the tract. Strain urine through gauze, crush any blood clots passed, and inspect the sides of the urinal and bedpan for clinging stones. Instruct the patient to report decreased urine volume, bloody or cloudy urine, fever, and any increase in pain. Monitor vital signs for early infection; treat infection with the appropriate antibiotic before attempting to dissolve the stone.

Teaching points. Explain the causes of stones and how to prevent recurrence, and encourage a regimen that includes high fluid intake. The patient should drink enough to excrete 3,000 to 4,000 mL of urine every 24 hours. Recommend urine cultures every 1 to 2 months the first year and periodically after that, with vigorous treatment of recurrent infection. Encourage mobility and discourage excessive vitamins (especially vitamin D) and minerals. After surgery, teach the signs and symptoms of complications to report and stress the importance of followup to assess kidney function and confirm all stones are gone. After ESWL, increase fluids to help pass fragments; expect hematuria and possibly a bruise on the treated side of the back; check temperature daily and notify the physician if it is greater than 38C (about 101F) or if pain is unrelieved by prescribed medication. Provide instructions for any necessary home care and followup.

Home and followup care after ESWL. Increase fluids to help pass stone fragments (may take 6 weeks to several months). Report fever, decreasing urinary output, and pain. Hematuria is anticipated but should subside in 24 hours. Give dietary instructions based on stone composition, and advise adherence to the prescribed diet to avoid further stones. Take enough fluid in the evening to prevent urine from becoming too concentrated at night.

Continuing care. Monitor closely to confirm treatment was effective and no complications developed. Assess the patient's understanding of ESWL and its complications, the factors that raise recurrence risk, and strategies to reduce them. Assess the patient's ability to monitor urinary pH and interpret results during followup. Ensure the patient knows the signs of stone formation, obstruction, and infection and the importance of reporting them promptly. If medications are prescribed to prevent stone formation, explain their actions, importance, and side effects.

Evaluation

The patient reports relief of pain, states increased knowledge of health-seeking behaviors to prevent recurrence, and experiences no complications.

Discharge Goals

1. Pain relieved or controlled.
2. Fluid and electrolyte balance maintained.
3. Complications prevented or minimized.
4. Disease process, prognosis, and therapeutic regimen understood.
5. Plan in place to meet needs after discharge.