Kidney function is critical clue to reducing preventable medication problems

Patient Safety and Quality
Kidney function is critical clue to reducing preventable medication problems
May 01, 2009

Accurate assessment of kidney (renal) function can help clinicians prescribe medication dosages that are less likely to cause adverse drug events (ADEs), according to a new study. Many medications are excreted via the kidney, so that impaired kidney function can lead to increased blood levels or prolonged retention of medications because of slowed removal from the body, with sometimes toxic results. To help avoid ADEs in patients with high or hidden risk of impaired kidney function, the researchers recommend that nurses routinely assess patient levels of creatinine in the blood and estimated rates of creatinine clearance, which are used together as measures of kidney function.

They collected information on 1,052 medication safety events (both actual and potential ADEs) including 318 medication errors reported on 17 clinical units at 2 urban, nonteaching community hospitals before the implementation of a commercial computerized physician order entry (CPOE) system. The researchers estimated creatinine clearance and used laboratory measurement of serum creatinine to classify each patient as being of high (144 patients), hidden (81 patients), or low (93 patients) risk of kidney-related medication events. High-risk patients had high levels of serum creatinine and low clearance rates, low-risk patients had low serum creatinine and high clearance rates, while hidden-risk patients had a combination of low serum creatinine and low clearance rates.

Age and sex were each significantly associated with renal risk groups: patients over 80 years old formed the largest group for hidden risk, while men were the largest group at high risk and more women than men had hidden risk. A third of the reported medication errors occurred in patients under 65 years old, a third in patients between ages 65 and 79 years, and a third among patients 80 years or older. Medication errors among patients with high or hidden risk of renal insufficiency primarily occurred during ordering or transcription of the order, and most often involved a wrong dose rather than wrong drug choice or frequency of administration.

The researchers found that antibiotics accounted for a fourth and diabetes drugs accounted for a sixth of medication errors. Antibiotics accounted for more than a third of the errors in the high-risk group and less than a fifth of errors for the hidden-risk and normal-risk groups. The study, which is part of a larger study of the impact of CPOE systems on the outcome of ADEs, was funded in part by the Agency for Healthcare Research and Quality (HS13131).

More details are in "Reducing preventable medication safety events by recognizing renal risk," by Willa Fields, D.N.Sc., R.N., Christine Tedeschi, M.S., R.N., Justine Foltz, B.A., R.N., and others, in 2008 Clinical Nurse Specialist 22(2), pp. 73–78.