Thromboelastography

This is a short overview of thromboelastography, covering how it works, parameters, and how those parameters might indicate underlying disorders of blood clotting.  

Information was adapted from TrueLearn, Wikipedia, and UpToDate. Images were adapted from Wikimedia Commons: By Mikael Häggström, M.D. Author info- Reusing images- Conflicts of interest:NoneMikael Häggström, M.D. - Own work. Sources:Dias JD, Haney EI, Mathew BA, Lopez-Espina CG, Orr AW, Popovsky MA (2017). "New-Generation Thromboelastography: Comprehensive Evaluation of Citrated and Heparinized Blood Sample Storage Effect on Clot-Forming Variables.". Arch Pathol Lab Med 141 (4): 569-577. DOI:10.5858/arpa.2016-0088-OA. PMID 28353382.Tyler PD, Yang LM, Snider SB, Lerner AB, Aird WC, Shapiro NI (2021). "New Uses for Thromboelastography and Other Forms of Viscoelastic Monitoring in the Emergency Department: A Narrative Review.". Ann Emerg Med 77 (3): 357-366. DOI:10.1016/j.annemergmed.2020.07.026. PMID 32988649., CC0, https://commons.wikimedia.org/w/index.... By Jan Hartmann, Matthew Murphy and Joao D. Dias - Hartmann J, Murphy M, Dias JD (2020). "Viscoelastic Hemostatic Assays: Moving from the Laboratory to the Site of Care-A Review of Established and Emerging Technologies.". Diagnostics (Basel) 10 (2). DOI:10.3390/diagnostics10020118. PMID 32098161. PMC: 7167835., CC BY 4.0, https://commons.wikimedia.org/w/index...

ADDITIONAL TAGS:
Tests efficiency of blood coagulation to monitor hemostasis.  Parameters: (remember them with rule of 6s)
R time: Time to initial clot formation (that is, amplitude deviation from baseline) ~ 6 minutes
K time: Time from initial clot formation until reaching 20 mm in amplitude
Alpha angle (α): Angle between the baseline at initial clot formation, and a tangent line that intersects the tracing curve. ~ 60 degrees
Maximum amplitude (MA): Maximum deviation of tracing to baseline.  ~ 60 mm
A30: Amplitude 30 minutes after reaching maximum amplitude.  ~ 6%