Correlation between partial thromboplastin time and thromboelastography in adult critically ill patients requiring bivalirudin for extracorporeal membrane oxygenation
Research article published in Pharmacotherapy (2023)
Abstract
STUDY OBJECTIVE: Thromboelastography (TEG) offers a more dynamic assessment of hemostasis over activated partial thromboplastin time (aPTT). However, the clinical utility of TEG in monitoring bivalirudin during extracorporeal membrane oxygenation (ECMO) remains unknown. The purpose of this study was to evaluate the correlation between aPTT and TEG in adult ECMO patients anticoagulated with bivalirudin. DESIGN: Multicenter, retrospective, cohort study conducted over a 2-year period. SETTING: Two academic university medical centers (Banner University Medical Center) in Phoenix and Tucson, AZ. PATIENTS: Adult patients requiring ECMO and bivalirudin therapy with ≥1 corresponding standard TEG and aPTT plasma samples drawn ≤4 h of each other were included. The primary endpoint was to determine the correlation coefficient between the standard TEG reaction (R) time and bivalirudin aPTT serum concentrations. MEASUREMENTS AND MAIN RESULTS: A total of 104 patients consisting of 848 concurrent laboratory assessments of R time and aPTT were included. A moderate correlation between TEG R time and aPTT was demonstrated in the study population (r = 0.41; p < 0.001). Overall, 502 (59.2%) concurrent assessments of TEG R time and aPTT values showed agreement on whether they were sub-, supra-, or therapeutic according to the institution's classification for bivalirudin. The 42.2% (n = 271/642) discordant TEG R times among "therapeutic" aPTT were almost equally distributed between subtherapeutic and supratherapeutic categories. CONCLUSIONS: Moderate correlation was found between TEG R time and aPTT associated with bivalirudin during ECMO in critically ill adults. Further research is warranted to address the optimal test to guide clinical decision-making for anticoagulation dosing in ECMO patients.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Peer-reviewed research on anticoagulant and antithrombotic drug development relevant to leech-derived and synthetic compounds. Indexed in PubMed and verified against the NCBI record.
Why This Matters for Hirudotherapy
This multicenter retrospective cohort study of 104 adult ECMO patients (848 paired samples) found only a moderate correlation (r = 0.41, p < 0.001) between thromboelastography R time and aPTT when monitoring the direct thrombin inhibitor bivalirudin, with concordance on therapeutic range in just 59.2% of paired assessments. Its relevance to hirudotherapy is indirect but real: bivalirudin is a synthetic analogue of hirudin, the anticoagulant peptide originally discovered in medicinal-leech saliva, so this work belongs to the broader clinical story of how leech-derived direct thrombin inhibitors are dosed and monitored in modern critical care. The caveat is that the study examines a manufactured drug, not leech therapy itself, and as a retrospective correlation analysis it describes lab-test agreement rather than patient outcomes — it says nothing about leech application.
Citation
Correlation between partial thromboplastin time and thromboelastography in adult critically ill patients requiring bivalirudin for extracorporeal membrane oxygenation.
Buckley et al. · Pharmacotherapy, 2023
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