Thrombelastography-estimated functional fibrinogen in healthy volunteers, end-stage renal disease, and trauma:...

Depletion of fibrinogen is an early event in trauma-induced coagulopathy (TIC), while hyperfibrinogenemia increases thrombotic risk in end-stage renal disease (ESRD). Viscoelastic tests aim to provide rapid fibrinogen estimates, yet their accuracy to define abnormal fibrinogenemia remains debated.

We assessed the accuracy of thrombelastography (TEG)-TEG 5000 and TEG 6s-in measuring normal and abnormal fibrinogen levels across healthy volunteers, patients with ESRD, and trauma patients at risk for TIC.

We compared the von Clauss functional fibrinogen (gold standard) with TEG 5000 functional fibrinogen level (FLEV) in 118 healthy volunteers, 52 patients with ESRD who underwent arteriovenous fistula surgery, and 265 severely injured patients. We compared Clauss fibrinogen with TEG 6s citrated functional fibrinogen (CFF) in 140 trauma patients at high risk for TIC. Pearson correlation was used.

Clauss fibrinogen correlated moderately with TEG 5000-FLEV in healthy volunteers (r = 0.52; P < .0001) and patients with ESRD overall (r = 0.62; P < .0001). Correlation, however, deteriorated and became nonsignificant in patients with ESRD with fibrinogen of > 500 mg/dL. Trauma patients showed moderate overall correlation (r = 0.58; P < .0001), but the correlation decreased substantially with fibrinogen of <150 mg/dL (r = 0.20; P = .29). TEG 6s-CFF had better overall correlation (r = 0.66; P < .0001), though decreased at fibrinogen<200 mg/dL (r = 0.39; P = .04).

Both TEG 5000-FLEV and TEG 6s-CFF correlated moderately with Clauss fibrinogen but decreased in correlation in both hyperfibrinogenemia and hypofibrinogenemia. Thus, we caution relying on TEG 5000 or TEG 6s to be the only laboratory measurement to guide fibrinogen replacement when resuscitating trauma patients at risk for TIC and TEG 5000-FLEV for assessing fibrinogen in patients with ESRD at risk for thrombotic events.