Whole Blood Cardiac Troponin "Triaging" to Improve Early Detection of Myocardial Injury at a Pediatric Hospital

• Published in: The journal of applied laboratory medicine 2024-05, Vol.9 (3), p.540-548
• Main Authors: de Koning, Lawrence, Seiden-Long, Isolde, Anker, Katherine, Myers, Kimberley, Stang, Antonia
• Format: Article
• Language: English
• ISSN: 2576-9456; 2475-7241; 2475-7241
• DOI: 10.1093/jalm/jfad133

The importance of offering on-site cardiac troponin (cTn) testing at pediatric hospitals may be underappreciated. We developed a rapid rule-in process for myocardial injury at a pediatric hospital experiencing delays in off-site high-sensitivity cardiac troponin T (hs-cTnT) testing. Collect-to-verify turnaround times (TATs) for off-site testing were reviewed. Pre-analytic changes to improve TATs were devised, implemented and evaluated, after which a new analyzer was selected and evaluated for on-site cTn testing. Performance of the new analyzer's assay was compared to the off-site hs-cTnT assay, and post go-live TATs for on-site testing were assessed. Median collect-to-verify TAT for short turnaround-time (STAT) priority off-site plasma hs-cTnT testing was 104 min, with 35% of orders having a TAT >120 min. Eliminating serum separator tubes and requiring a separate plasma separator tube did not significantly reduce TATs. A QuidelOrtho Triage® MeterPro whole blood cardiac troponin I (cTnI) assay was implemented to "triage" time-critical and STAT priority specimens collected for off-site hs-cTnT testing. Elevated cTnI (≥0.02 µg/L) had a sensitivity of 91% for clear elevations in hs-cTnT (≥53 ng/L) but a 0% sensitivity for modest elevations (5 to 13 ng/L, 14 to 52 ng/L). An interpretive comment was auto-appended to cTnI results indicating that clinicians should wait for the hs-cTnT result if cTnI was normal. Median collect-to-verify TAT for on-site cTnI testing was