Objective Automated clinical decision support (CDS) has shown promise in improving safe medication use. We performed a trial of CDS, given both during computerized physician order entry (CPOE) and in response to new laboratory results, comparing the time course of clinician behaviors related to digoxin use before and after implementation of the alerts.

Design Alerts were implemented to notify of potential risk from low electrolyte concentrations, or unknown digoxin or electrolyte concentrations during CPOE. Alerts were also generated in response to newly reported hypokalemia and hypomagnesemia in patients given digoxin.

Measurements Clinician responses to the alerts for 6-months were compared to responses to similar situations for 6-months prior to implementation.

Results During CPOE, checking for unknown serum values increased after implementation compared to control at one hour: 19% vs. 6% for digoxin, 57% vs. 9% for potassium, and 40% vs. 12% for magnesium; as well as at 24 hours (p<0.01 for all comparisons). Electrolyte supplementation increased with newly reported hypokalemia and hypomagnesemia after implementation at one hour: 35% vs. 6% and 49% vs. 5% for potassium and magnesium respectively; as well as at 24 hours (p<0.01 for all comparisons). During CPOE, supplementation for hypokalemia was not improved, while supplementation for hypomagnesemia improved at 1 hour (p<0.05).

Conclusions Overall, the alerts improved the safe use of digoxin. During CPOE, alerts associated with missing levels were effective. For hypokalemia and hypomagnesemia, the alerts given during CPOE were not as effective as those given at the time of newly reported low electrolytes.