Emergency intravenous pyelography in the setting of possible renal colic: is it indicated?

STUDY OBJECTIVE

To determine whether emergency IV pyelography (IVP) adds significant information to clinical judgment in the setting of possible renal colic.

DESIGN

A prospective voluntary survey of a convenience sample of physicians at the time of patient encounter.

SETTING

The emergency department of a university hospital, annual census 50,000 visits.

PARTICIPANTS

Emergency medicine faculty physicians.

INTERVENTION

Physicians were surveyed before and after IVP was performed on patients with possible renal colic.

RESULTS

Over the course of 12 months, 62 patients with possible kidney stones were evaluated by 14 different faculty ED physicians, who filled out surveys. Before IVP results were obtained, 63% of patients were thought to have a high (more than 75%) probability of ureteral obstruction. In 59% of these patients, the IVP results showed ureteral obstruction. The IVP revealed unexpected findings in 42% of all patients, including normal results in 19%, ureteral stones in 5%, higher than expected grade of obstruction in 6%, and lower than expected grade of obstruction in 6%, and lower than expected grade of obstruction in 5%. Management was reported to have been changed in 60% of all patients for a wide variety of reasons, but consideration of alternative diagnosis was the most common reason, occurring in 23%. Management changes included unexpected hospital admission in five patients (9%) and emergency urologic consultation in five patients (9%).

CONCLUSION

Emergency IVPs are useful in the evaluation of patients with suspected renal colic, primarily when they rule out ureteral obstruction and allow consideration of alternative diagnoses. Not uncommonly, emergency urologic consultation or hospitalization occurs on the basis of IVP findings.