Blood Urea Testing by Nurse Practitioners in Newfoundland and Labrador
Introduction
This campaign provides information on the use of blood urea tests by Nurse Practitioners in NL.
Practice Points
- Although blood urea provides a measure of kidney function, it is not necessary to evaluate stable kidney function.
- Serum creatinine and estimated GFR (eGFR) is sufficient to evaluate stable kidney function; if you order a serum creatinine for this purpose, a blood urea is not necessary.
- In acute kidney injury, blood urea may be useful to assess the cause. Urea that is disproportionately high compared to the rise in creatinine may be seen in conditions where there is volume depletion, hypercatabolism or bleeding into the upper GI tract.
The Problem
There is an overuse of blood urea testing without clinical indication.
Our Data
In nurse practice, blood urea is usually ordered with serum creatinine, and is unnecessary in stable patients.
Note: Tests from inpatients, Emergency Rooms and Heart Failure Clinics have been omitted as Urea Tests are ordered routinely in these practice settings and could be considered appropriate.
| Abnormals | Percentage |
| B Urea>7 mmol/l | 34.6% |
| Sr. Creatinine High | 19.9% |
| eGFR<60 ml\min | 26.6% |
High blood urea with normal eGFR in stable patients creates unnecessary diagnostic confusion.
16.4% of people with normal eGFR have elevation in blood urea, but rarely above 10 mmol/L.
Top 20 Nurse Practitioners by Volume of Blood Urea Test
What You Can Do
In cases when kidney function is being assessed in stable out-patients:
- Consider if Blood Urea Testing is redundant.
- Remember that Blood Urea Testing usually mirror changes in creatinine and eGFR.