Detection of adverse drug events using an electronic trigger tool.

Purpose: Implementation and refinement of an integrated electronic "trigger tool" for detecting adverse drug events (ADEs) is described.

Methods: A three-month prospective study was conducted at a large medical center to test and improve the positive predictive value (PPV) of an electronic health record-based tool for detecting ADEs associated with use of four "trigger drugs": the reversal agents flumazenil, naloxone, phytonadione, and protamine. On administration of a trigger drug to an adult patient, an electronic message was transmitted to two pharmacists, who reviewed cases in near real time (typically, on the same day) to detect actual or potential ADEs. In phase 1 of the study, any use of a trigger drug resulted in an alert message; in subsequent phases, the alerting criteria were narrowed on the basis of clinical criteria and laboratory data with the goal of refining the trigger tool's PPV.

Results: A total of 87 drug administrations were reviewed during the three-month study period, with 27 ADEs detected. PPV values in phases 1, 2, and 3 were 0.33, 0.21, and 0.36, respectively. The relatively low overall PPV of the trigger tool was largely attributable to false-positive trigger messages associated with phytonadione use (such messages were reduced from 35 in phase 1 to 7 in phase 3).

Conclusion: Evaluation and refinement of an electronic trigger tool based on detecting the use of the reversal agents flumazenil, naloxone, phytonadione, and protamine found an overall PPV of 0.31 during a three-month study period.