Rosen & Barkin's 5-Minute Emergency Medicine Consult (605 page)

• Sudden onset of severe pain in the costovertebral angle, flank, and/or lateral abdomen
  
• Colicky or constant pain:
  
  • Patient cannot find a comfortable position
    
• Hematuria:
  
  • Gross hematuria in 1/3 of patients
    
• Nausea/vomiting
  
• Diaphoresis
  
• History of prior stone formation
  

• Vital signs:
  
  • Fever suggests an occult infection.
    
  • Hypotension with an altered mental status suggests urosepsis
    
• Abdominal exam:
  
  • Tenderness to palpation, rebound tenderness, or guarding suggests a more serious intra-abdominal process
    
  • Palpate the abdominal aorta for tenderness or pulsatile enlargement suggestive of an aneurysm
    
• Genitourinary exam:
  
  • Examine the genitalia for evidence of hernia, epididymitis, torsion, or testicular masses
    

• Urinalysis
  
  • Microscopic hematuria present in >80%
    
  • Gross hematuria
    
  • Absent urinary blood in 10–30%
    
  • WBC/bacteria suggests infection
    
  • No correlation between the amount of hematuria and the degree of urinary obstruction
    

• CBC:
  
  • WBC >15,000 suggests concomitant infection
    
• Urine culture
  
• Electrolytes, glucose, BUN, creatinine
  
• Pregnancy test when suggestive
  

• CT:
  
  • Helical CT has replaced IV pyelogram (IVP) as test of choice
    
  • Detects calculi as small as 1 mm in diameter
    
  • Directly visualizes complications, such as hydroureter, hydronephrosis, and ureteral edema
    
  • Advantages over IVP:
    
    • Performed rapidly
      
    • Does not require IV contrast media
      
    • Detects other nonurologic causes of symptoms, such as abdominal aortic aneurysms (AAAs)
      
  • Disadvantages:
    
    • Does not evaluate flow or renal function
      
  • Nonenhanced helical CT in the evaluation of renal colic:
    
    • Sensitivity 95%
      
    • Specificity 98%
      
    • Accuracy 97%
      
  • Indications:
    
    • 1st-time diagnosis
      
    • Persistent pain
      
    • Clinical confusion with pyelonephritis
      
• IVP:
  
  • Establishes diagnosis in 95%
    
  • Demonstrates the severity of obstruction
    
  • Scout film prior may localize stones that would otherwise be obscured by the dye.
    
  • Postvoiding film
    
  • Useful to identify stones at the ureteral vesicular junction or distal ureter that are obscured by a full bladder
    
• Kidney, ureter, and bladder (KUB) radiograph:
  
  • Indicated when allergy to IVP dye and when renal scanning and US not available
    
  • Distinguishes calcium-bearing stones (radiopaque) from noncalcium stones
    
  • Assists in locating radiopaque stones and the exclusion of other pathologies in nonpregnant patients
    
  • Difficult to distinguish radiopaque body:
    
    • Phlebolith
      
    • Bowel contents
      
    • Obstruction within the urinary tract on the KUB
      
    • Oblique films assist in localizing suspicious calcifications.
      
• US:
  
  • Useful in the detection of larger stones and hydronephrosis
    
  • Provides anatomic information only
    
  • Helpful in diagnosing obstruction and localizing stones in the proximal and distal portions of the ureter
    
  • Ability to detect hydronephrosis:
    
    • Sensitivity 85–94%
      
    • Specificity 100%
      
  • Limitations:
    
    • May miss stones <5 mm in size
      
    • May miss an obstruction in the early phase of renal colic
      
    • Time delay until the onset of pyelocaliectasis even after total obstruction
      

• Every effort should be made to minimize ionizing radiation exposure to the fetus
  
• US is the imaging modality of choice
  

Ureteroscopy, shock-wave lithotripsy, percutaneous nephrolithotomy

• Dissecting or rupturing AAA
  
• Pyelonephritis
  
• Papillary necrosis (sickle cell disease, NSAID analgesic abuse, diabetes, or infection)
  
• Renal infarction (vascular dissection or arterial embolus)
  
• Ectopic pregnancy
  
• Ovarian cyst/torsion
  
• Appendicitis
  
• Intestinal obstruction
  
• Biliary tract disease
  
• Musculoskeletal strain
  
• Lower lobe pneumonia
  
• Malingering or narcotic dependence (diagnosis of exclusion)
  

TREATMENT

Parenteral opiates may be required for pain control with long transport times

• Rapid dipstick urine test for blood:
  
  • Positive test in conjunction with clinical findings sufficient to begin analgesic therapy
    
• Provide adequate analgesia when diagnosis suspected on clinical and lab findings
  

• Hydration:
  
  • Initiate IV crystalloid infusion with 1 L of normal saline infused over 30–60 min followed by 200–500 mL/h
    
  • Bolus volume compromised patients with 500 mL increments until urine output adequate
    
• Analgesics (morphine, ketorolac):
  
  • Combination of IV NSAIDs and opioids decrease ED stay and provide better pain control than either alone
    
• Antiemetics (prochlorperazine, ondansetron, droperidol, hydroxyzine)
  
• α-Blockers (tamsulosin) or calcium-channel blockers (nifedipine) have been shown to decrease time to spontaneous stone passage:
  
  • Most efficacious for stones <5 mm in diameter
    
  • Tamsulosin and nifedipine equally effective
    
  • Prescribe on discharge
    

Avoid NSAIDs in pregnancy, particularly in 3rd trimester

• Hydromorphone (Dilaudid): 1–4 mg (peds: 0.015 mg/kg/dose) IM/IV/SC q4–6h PRN. Reduce dose in opiate-naive patients.
  
• Hydroxyzine hydrochloride (Vistaril): 25–50 mg (peds: 0.5–1 mg/kg/dose) IM (not IV) q4–6h
  
• Ketorolac (Toradol): 30–60 mg IM or 30 mg (peds: 0.5 mg/kg/dose up to 1 mg/kg/24–48 h) IV (alone or with opiates); reduce dose to 30 mg IM or 15 mg IV if >65 yr or <50 kg.
  
• Morphine sulfate: 2–10 mg (peds: 0.1–0.2 mg/kg/dose q2–4h) IM/IV/SC q2–6h PRN; may redose more frequently if needed
  
• Nifedipine 30 mg PO daily.
  
• Ondansetron (Zofran): 4 mg (peds: 0.1 mg/kg ×1) IM/IV, not to exceed 8 mg/dose IV.
  
• Prochlorperazine (Compazine): 5–10 mg IM/IV q4–6h; 25 mg suppository PR
  
• Promethazine (Phenergan): 12.5–25 mg (peds: 0.25–1 mg/kg not to exceed 25 mg) IM/IV/PR q4–6h
  
• Tamsulosin (Flomax) 0.4 mg PO daily for 4 wk
  

FOLLOW-UP

• Obstruction in the presence of infection mandates immediate urologic intervention.
  
• Intractable pain with refractory nausea and vomiting
  
• Severe volume depletion
  
• Urinary extravasation
  
• Hypercalcemic crisis
  
• Solitary kidney and complete obstruction
  
• Relative admission indications (discuss with urologist):
  
  • High-grade obstruction
    
  • Renal insufficiency
    
  • Intrinsic renal disease
    
  • Stones of size <5 mm usually pass spontaneously; those >8 mm rarely do.
    

• Normal vital signs
  
• No evidence of concomitant urinary tract infection
  
• Adequate analgesia
  
• Able to tolerate PO fluids to maintain hydration status
  
• Reliable patient with an adequate home situation
  
• Appropriate outpatient follow-up arranged
  
• Normal renal function
  
• Provide a urine strainer to collect the stone for possible future stone analysis
  
• Arrange urologic follow-up
  

Imaging if pain persists and diagnosis not established in ED

All patients should have urology follow-up, especially:

• 1st episode of renal stone
  
• Large stone >5 mm
  
• Patients who fail to pass a stone after 4 wk of conservative therapy
  

• Do not miss a vascular catastrophe mimicking as renal colic
  
• Aggressive pain management and hydration promote passage of stones
  
• The absence of hematuria does not exclude the diagnosis of acute renal colic
  

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• Marx JA, Hockberger RS, Walls RM, eds.
  Rosen’s Emergency Medicine: Concepts and Clinical Practice
  . 7th ed. St. Louis, MO: Mosby; 2009.
  
• Schissel BL, Johnson BK. Renal stones: Evolving epidemiology and management.
  Pediatr Emerg Care.
  2011;27(7):676–681.
  
• Teichman JM. Clinical practice. Acute renal colic from ureteral calculus.
  N Engl J Med
  . 2004;350:684–693.
  
• Worcester EM, Coe FL. Clinical practice. Calcium kidney stones.
  N Engl J Med.
  2010;363(10):954–963.
  

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