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Three Part Question

In [adult patients with suspected biliary colic] is [glycopyrrolate superior to placebo]at [decreasing pain]

Clinical Scenario

A previously healthy overweight 38-year-old female comes to your Emergency Department complaining of postprandial right upper quadrant abdominal pain and vomiting for the last two hours. She appears to be in pain and is mildly tachycardic, but vital signs are otherwise normal. She has tenderness in the right upper quadrant without guarding. You want to know if glycopyrrolate is a reasonable medication to use to treat her pain initially.

Search Strategy

Medline 1966-06/06 using the OVID interface, Cochrane Library (2006), PubMed
clinical queries.
[(exp glycopyrrolate OR glycopyrrolate.mp) AND (exp cholelithiasis OR cholelithiasis.mp OR exp cholecystitis OR cholecystitis.mp OR exp cholecystitis, acute )]. LIMIT to human AND English

Search Outcome

2 papers found of which only 1 paper was relevant

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Antevil J et al February 2005 USA	Convenience sample of 38 adults presenting to an academic military hospital with acute right upper quadrant or epigastric pain. Patients were randomized to receive either glycopyrrolate or placebo.	Double-blind, prospective, randomized trial. Pain level assessed using a 100-mm visual analog pain scale administered by someone not directly involved with the patient's care.	Pain relief using visual analog scale every 20 minutes.	No difference in pain relief between glycopyrrolate and placebo.	Very small sample size. There were 180 patients who met inclusion criteria, 60 of whom refused to participate, and 81 of whom were not offered enrollment by the treating physician. Early termination of the study due to poor enrollment. Convenience sampling may have resulted in selection bias. Considering that all patients would have to wait 20 minutes before being given a rescue analgesic with proven efficacy, treating physicians would likely have excluded those with more severe pain. 42% of patients had a normal ultrasound, indicating that there pain was likely from a different source than biliary colic.

Comment(s)

The small sample size in this study really limits its utility in answering the clinical question. However, the fact that placebo actually showed a trend toward greater pain relief than glycopyrrolate should make one question the ethicals of using glycopyrrolate at all when there are other medications with proven analgesic effect (i.e. narcotics).

Clinical Bottom Line

There is no evidence to support the use of glycopyrrolate to treat pain associated with suspected acute biliary colic.

References

1. Antevil J, Buckley R, Johnson A, Woolf A, Thoman D, Riffenburgh R Treatment of Suspected Symptomatic Cholelithiasis With Glycopyrrolate: A Prospective Randomized Clinical Trial Annals of Emergency Medicine February, 2005; 172-176