Disorders of the Urinary System Renal Stones

Renal Stones Renal staghorn calculus Variations in composition and environment (acidic or alkaline) Major types including hereditary type Identify the type and cause Preventive measures based on type Appropriate method of treatment

Causative Factors Supersaturation of the urine with crystalloids that do not readily dissolve (e.g., calcium, uric acid, and cystine) Urinary infections, which can produce bacteria and other debris that form a core for stone formation Inadequate fluid intake, which results in concentrated urine and inadequate flushing of the urinary tract

Causative Factors (cont.) Sluggish flow of urine, as may occur with bed rest or immobility Certain substances in the urine (e.g., urate, a salt of uric acid), which encourage the formation of crystals of calcium oxalate or calcium phosphate

Renal Staghorn Calculus See Figure 35-1 on p. 792.

Stone Types Calcium oxalate (most common) Calcium phosphate Uric acid Struvite (more common in women) Cystine See Table 35-2 on p. 792.

Etiology and Pathophysiology Calcium stones and parathyroid tumor Males > females Family history of stones History of intestinal bypass surgery for obesity Immobility History of recurrent urinary tract infection

Prevention Adequate flow of dilute urine through the kidney Prevent UTI Urinary pH modification—ascorbic acid or dietary modifications

Signs and Symptoms Severe pain—stones that are small enough to move along Flank pain radiates downward to genitalia and inner thigh. This causes obstruction and swelling of ureter Nausea and vomiting

Diagnosis UA and KUB IVP Serum levels of calcium, uric acid, and cystine

Treatment Flushing the stone—oral intake or IV infusion Pain management—opioids, NSAIDs, and antispasmodics Antibiotics Irrigation via ureteral catheter or percutaneous nephrostomy

Nursing Management Pain management Fluid intake of 3000-4000 mL Early ambulation Adjunctive therapy for ESWL: corticosteroids, calcium channel blockers, alpha agonists Percussion, diuresis, and inversion (PDI) therapy

Nursing Management (cont.) Cystoscopy or surgery Nephrolithotomy, pyelolithotomy, and ureterolithotomy Monitor: infection, hemorrhage, and leakage of fluid Initial assessment: Changes in urinary output, characteristics of the urine, risk factors and history, and other assessment data Straining of urine