Correcting Low Maximum Amplitude on Thromboelastography

Understanding Low MA on TEG

Maximum Amplitude (MA) represents the maximum strength of the clot and primarily reflects platelet function and fibrinogen concentration 1
Decreased MA suggests thrombocytopenia, platelet dysfunction, or fibrinogen deficiency 1
Normal MA values typically range from 50-70 mm, with values <50 mm indicating significant clot strength impairment 1

If functional fibrinogen TEG is unavailable, consider conventional laboratory tests (platelet count and fibrinogen level) to guide therapy 2
Check for concurrent abnormalities in other TEG parameters that may indicate additional coagulation issues 1

If platelet count <50,000/mm³ or there is evidence of platelet dysfunction, administer platelet transfusion (1 adult dose) 2
Target platelet count >50,000/mm³ for most bleeding scenarios 2
Consider higher platelet count targets (>100,000/mm³) for patients with traumatic brain injury or requiring neurosurgery 2
If fibrinogen level <1.5-2.0 g/L or functional fibrinogen TEG shows decreased contribution, administer fibrinogen concentrate (first choice) at 25-50 mg/kg 3
Target fibrinogen level of at least 1.5-2.0 g/L in bleeding patients 3

In liver disease patients, TEG may provide more valuable information than standard coagulation tests 3

Do not rely solely on conventional coagulation tests (PT, aPTT) as they may not correlate well with TEG parameters 2
Avoid treating based on isolated laboratory values without considering the clinical context 1
Remember that anemia can paradoxically show hypercoagulable TEG results due to decreased blood viscosity, potentially masking coagulopathy 1
Standard TEG is insensitive to antiplatelet agents and cannot reliably detect platelet dysfunction 1

The American Society of Anesthesiologists recommends administering fibrinogen concentrate (25-50 mg/kg) as first-line treatment for low Maximum Amplitude (MA) on CFF TEG, targeting a fibrinogen level of at least 1.5-2.0 g/L, with alternative options including 2 pools of cryoprecipitate (equivalent to 4g fibrinogen replacement) 4
Higher fibrinogen targets (>2.0 g/L) may be needed in obstetric hemorrhage, according to the American College of Obstetricians and Gynecologists 4, 5
Goal-directed therapy using TEG parameters has been shown to improve outcomes compared to conventional coagulation test-guided therapy in trauma patients, as recommended by the European Society of Intensive Care Medicine 6
Anemia can paradoxically show hypercoagulable TEG results due to decreased blood viscosity, potentially masking coagulopathy, and standard TEG is insensitive to antiplatelet agents and cannot reliably detect platelet dysfunction, according to the International Society on Thrombosis and Haemostasis 7
The high variability of TEG measurements (coefficients of variance ranging from 7.1% to 39.9%) necessitates proper training and regular calibration, as emphasized by the American Society for Clinical Pathology 7