A 61-year-old male is diagnosed with a large haemothorax after a fall. He has a history of atrial fibrillation and takes rivaroxaban. He becomes increasingly hypoxic and hypotensive and a decision is made to urgently correct the coagulopathy and insert a chest drain.
His first set of coagulation tests are as follows:
Parameter |
Patient Value |
Adult Normal Range |
International normalised ratio (INR) |
2.0* |
0.9 – 1.3 |
Activated partial thromboplastin time (APTT) |
37.0 sec |
27.0 – 38.5 |
Fibrinogen |
5.4 g/L* |
2.0 – 4.0 |
a) What is the mechanism of action of rivaroxaban? (10% marks)
b) What other information do you need from history and investigations to make an assessment of his coagulation status? (40% marks)
c) What steps will you take to correct his coagulopathy? (50% marks)
Not available.
a) Mechanism of action
b)
Additional history:
Additional investigations:
c)
Correction of coagulopathy:
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Almegren, Mosaad. "Reversal of direct oral anticoagulants." Vascular health and risk management 13 (2017): 287.
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Siegal, Deborah M., et al. "Andexanet alfa for the reversal of factor Xa inhibitor activity." New England Journal of Medicine373.25 (2015): 2413-2424.
Galliazzo, S., M. P. Donadini, and W. Ageno. "Antidotes for the direct oral anticoagulants: What news?." Thrombosis research164 (2018): S119-S123.