Date: April 14, 2013

Case Scenario: A 46-year-old man presents to the emergency department doing the renal colic shuffle (not the Harlem Shake). He has a history of kidney stones. Nothing in his physical examination or investigations suggest anything other than another renal colic attack. He wants to know if there is a way to flush the stone out.

From TheSGEM Episode #4 (Getting Un-Stoned) you know that an apha blocker does not help pass stones beyond the placebo effect. We are still waiting for the big systematic review by Zhu from Cochrane on the topic.

Question: Does pushing oral/IV or diuretics help in passing kidney stones?

Reference: Worster AS, Bhanich Supapol W. Fluids and diuretics for acute ureteric colic. Cochrane Database of Systematic Reviews 2012

  • Population: Adults ED patients with acute renal colic
  • Intervention: High volume IV or oral fluids or diuretic use
  • Control: Placebo, no treatment or maintenance IV or oral hydration
  • Outcome: Symptoms and duration, physician visits, hospital admit, surgical procedures or adverse events

Results: Two studies (n=118) looked at IV fluids

  • No difference in pain at six hours (RR 1.06, 95% CI 0.71 to 1.57)
  • No difference in stone clearance (1 study 43 participants: RR 1.38, 95% CI 0.50 to 3.84), hourly pain score or patients’ narcotic requirements (P >0.05 for all comparisons)
  • No difference surgical stone removal (1 study, n=60: RR 1.20, 95% CI 0.41 to 3.51)
  • No difference manipulation by cystoscopy (1 study, 60 n=60: RR 0.67, 95% CI 0.21 to 2.13)

Authors’ Conclusions: “We found no reliable evidence in the literature to support the use of diuretics and high volume fluid therapy for people with acute ureteric colic. However, given the potential positive therapeutic impact of fluids and diuretics to facilitate stone passage, the capacity of these interventions warrants further investigation to determine safety and efficacy profiles.”

BEEM Comments: 

  • Two small studies (n=118)
  • Lack of clinical evidence of benefit
  • Theoretical potential harm (renal impairment or ureteric rupture from high volume IV)
  • These treatments should not be routinely used

BEEM Bottom Line: You don’t need to push fluids (oral/IV) or use diuretics to pass kidney stones

Case Resolution: You treat him with some IV fluids and 30mg ketorolac IV. His symptoms resolve. Imaging demonstrates a small, distal stone with no hydronephrosis. He is instructed to return if new symptoms, existing symptoms get worse or he is worried. His follow up is with his primary care provider or urologist. 

KEENER KONTESTLast weeks winner was Chris Bond. He is a Canadian EM resident, FOAMed blogger, dogma basher and wine and food supergeek. Chris was first to say fondaparinux 2.5mg sc daily for 45 days for the treatment of superficial thrombophlebitis to relieve symptoms and prevent extension to DVT/PE.

Be sure to listen to this weeks podcast for another chance to a cool skeptical prize. Email your answer to TheSGEM@gmail.com.  Use “Keener Kontest” in the subject line. First one to email me the correct answer wins.

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Remember to be skeptical of anything you learn, even if you heard it on The Skeptics’ Guide to Emergency Medicine.