Troponin intervals and order sets

Correct testing intervals are critical to ensure optimal test strategy and incorrect test intervals can delay diagnosis.  Perhaps one of the most common test intervals we all deal with is troponin test intervals.  For years we’ve known troponin should be collected every 3-4 hours (non high sensitivity) for a total of 3 tests to rule out myocardial infarction.  Sometimes there might be sound clinical reasons to deviate and perform testing at greater duration but unfortunately many clinicians elect to do testing every 6 hours only because it aligns with testing intervals for outdated CK-MB.  I knew our hospital was all over the place with troponin testing yet at the same time we were always being challenged to reduce our chest pain work-up time.  This gave our laboratory an opportunity to speak up and challenge the status quo.  As it turned out our troponin intervals were established by order sets that laboratory had never been asked to review. With laboratory guidance our order sets were corrected to collect troponin every 3 hours instead of every 6 hours and we saw a corresponding decrease in chest pain length of stay.  As more and more hospitals now convert to high sensitivity troponin, attention to 1-2 hour test intervals will only grow.

In 2020 I wrote a paper in the Journal of Applied Laboratory Medicine documenting the wide variance of troponin testing intervals in the US.  Where does your hospital fall in comparison?

In the end this issue is not really just about troponin.  Instead it’s about laboratory having a voice in the creation and maintenance of order sets.  But troponin is a good way to get started.  If your test intervals are not optimal it can be used as an opportunity for your laboratory to speak up and drive efficiency.  Doing so helps us show the full value of the laboratory.