Ureteral Expulsive Therapy
Annals of Emergency Medicine November 2007 & Critical Decisions in Emergency Medicine March 2011
Singh, Alter, and Littlepage MD’s
Acute renal colic is common complaint of patients presenting to the Emergency Department. Typical treatment includes pain control and IV fluids.
Recent studies have looked at benefits of calcium channel blockers and alpha-antagonists to help expel moderate sized distal ureteral stones.
Calcium channel Blockers
- nifedipine
- verapamil
- diltiazem
Side effects: transient hypotension, dyspepsia, headache, palpitations, and reduction in mean blood pressure
1.5 times sooner expulsion than standard therapy.
Number needed to treat = 3.9
Average stone size <5 mm
Alpha-antagonists
- tamsulosin
- terazosin
- doxazosin
- alfuzosin
- prazosin
Side effects: dizziness, headache, asthenia, nausea and vomiting
This is a systematic review of medical expulsive therapy. Medication thought to act by relaxing ureteral smooth muscle.
16 studies of alpha-antagonists (NNT number needed to treat = 3.3)
- majority of stones less then 5 mm
9 studies using calcium channel blockers (NNT = 3.9)
- stone size ranged from 1.8 to 3 mm
Adverse effects 4% in alpha-antagonist vs. 15.2% calcium channel blockers
These showed a 2-6 day reduction in expulsion time.
Both types of medication were shown to significantly improve passage of stones. Improve average time it takes to pass a stone with the addition of these medications. Without medication < 5 mm stone would pass by itself usually within 4 weeks.
2 week course of therapy recommended
In the study they describe a small stone as < 5 mm
So what are moderately sized stones? I assume this is >5 mm.
In the review of these studies it appears that there is no definitive conclusion that medical expulsive therapy is of enough benefit in stones < 5 mm.
However, there is no doubt it is beneficial for stones > 5 mm. Based on the adverse effects I would lean more towards alpha – antagonists.
Kidney stones continue to be a common diagnosis in the emergency department with lots of people presenting with symptoms of flank pain, writhing around in bed, urinary urgency, frequency, nausea & vomiting, and hematuria (not found in 10%). Ct scans may not always be needed to make the diagnosis especially if the patient has had multiple stones that have passed without need for intervention. In elderly or patients over the age of 50 years old always consider abdominal aortic aneurysm leak or rupture as a cause of similar symptoms. CT scan in this case may be warranted as well as bedside ultrasound which can speed the diagnosis. Always look at the skin of patient as well to be sure not to miss a rash making the diagnosis of shingles without any further testing.
Treatment of ureterolithiasis generally consists of urine strainer, increased fluids, analgesia (narcotic & NSAIDs), CCB or alpha antagonist. Return to emergency room for fever, vomiting, or intractable pain. Follow up with Urology if you haven’t passed the stone in a few weeks or you continue to have pain.