Analysis of Inpatient and Emergency Department Serial Troponin Testing Intervals in the United States.

Abstract

Serial measurement of cardiac troponins (cTn) is central to the diagnosis of myocardial infarction. The time intervals between individual measurements may impact the speed and reliability of diagnosis. Published recommendations exist for these time intervals, but there is little previously published data on actual intervals in routine clinical settings. Retrospective analysis of cTn testing intervals was performed from a convenience sample of 37 hospitals. All 37 provided data on inpatient tests and 19 also provided separate data for tests ordered in their emergency departments. Facilities included both academic and community hospitals across the United States. For each facility, the median time interval between serial cTn order collections was determined separately for inpatient orders and emergency department orders. The facility-level median time intervals between serial inpatient cTn test orders ranged from 3.17 to 7.32 hours. Facility-level median time intervals between serial emergency department cTn orders ranged from 1.48 to 4.23 hours. There was no observed difference between academic and nonacademic facilities. Typical time intervals between serial cTn orders varied widely across hospitals, and in many cases reflected suboptimal care. Time intervals were generally shorter for cTn testing ordered in emergency departments. Existing testing protocols should be re-examined.