How to correct high FLEV on TEG?

Correcting High FLEV on TEG

When correcting high Functional Fibrinogen Level (FLEV) on TEG, it's important to recognize that TEG-FLEV often overestimates fibrinogen levels compared to the Clauss method, which may lead to undertreatment or delayed treatment of hypofibrinogenemia.

Understanding High FLEV on TEG

• TEG-FLEV measures functional fibrinogen levels but has been shown to significantly overestimate fibrinogen when compared to the gold standard Clauss method 1, 2
• This overestimation occurs in various populations including healthy volunteers, pregnant women, and patients with hemorrhage 2
• The mean difference between Clauss and FLEV measurements can be as high as 133-159 mg/dL, with FLEV consistently reporting higher values 2

First-Line Approach

• Do not rely solely on TEG-FLEV values for fibrinogen assessment; instead, use the Clauss method when available for accurate fibrinogen measurement 1, 2
• When managing patients with potential hypofibrinogenemia, consider that actual fibrinogen levels may be lower than indicated by TEG-FLEV 1
• For patients with active bleeding and suspected fibrinogen deficiency, administer fibrinogen replacement therapy based on Clauss method results rather than TEG-FLEV 1, 3

Fibrinogen Replacement Options

• Administer fibrinogen concentrate (first choice) at 4g for adults or cryoprecipitate to restore fibrinogen levels 3
• Target a fibrinogen level of at least 1.5-2.0 g/L in bleeding patients, with higher targets (>2.0 g/L) recommended in obstetric hemorrhage 3
• If fibrinogen concentrate or cryoprecipitate is unavailable, consider Fresh Frozen Plasma (FFP) at 10-15 mL/kg 3

Monitoring and Follow-up

• After fibrinogen replacement, reassess using the Clauss method rather than TEG-FLEV to accurately determine if target levels have been achieved 1, 2
• Continue monitoring both TEG parameters and conventional coagulation tests to guide ongoing treatment 4
• Repeat fibrinogen measurements after each dose of replacement therapy until target levels are achieved and bleeding is controlled 3

Special Considerations

• In obstetric patients, the discrepancy between FLEV and Clauss method is particularly important, as FLEV fails to detect significant differences between healthy pregnant women and those with postpartum hemorrhage 1, 2
• In liver disease patients, TEG may provide valuable information beyond standard coagulation tests, but FLEV values should still be interpreted with caution 4, 3
• For trauma patients with ongoing hemorrhage, rapid assessment and correction of coagulopathy is critical, but FLEV overestimation may lead to inadequate fibrinogen replacement 5

Pitfalls to Avoid

• Do not delay treatment while waiting for laboratory results in cases of severe bleeding; clinical judgment should guide initial management 1, 4
• Avoid relying solely on conventional coagulation tests (PT, aPTT) as they may not correlate well with clinical bleeding 4, 6
• Remember that TEG-FLEV overestimates fibrinogen levels, which may lead to undertreatment of hypofibrinogenemia, particularly in critical situations 1, 2
• Do not use tranexamic acid in patients with cirrhosis and active variceal bleeding as it provides no benefit and may increase thrombotic risk 1