A case report on therapeutic anticoagulation in the management of a COVID-19 patient on antiplatelets post-CABG — how much is enough?

Background
Coronavirus disease (COVID-19) predisposes patients to both arterial and venous thrombosis due to excessive inflammation, platelet activation, endothelial dysfunction, and stasis. Therefore, therapeutic anticoagulant therapy has been an integral part for management in patients with moderate to severe COVID-19 disease. We shall here discuss the concerns of starting anticoagulants in patients with COVID-19 disease who are already on antiplatelets, an unexplored area.
Case presentation
We herein report a case of 61-year-old patient with hypertension and diabetes mellitus type 2 with COVID-19 disease. Patient also had coronary artery disease and underwent CABG 4 years ago and was on aspirin 75-mg HS, clopidogrel 75-mg OD, and tab atorvastatin 40-mg HS. Patient was hemodynamically stable and was maintaining a saturation of 66% on room air and a saturation of 96% on 0 by high FiO partial rebreathing face mask. On auscultation, crepitations were present in bilateral lower lung fields. The patient was admitted under moderate category of COVID-19 SARS in the intensive care unit (ICU). Despite of standard care and treatment, in next 2 days, the oxygenation deteriorated Pa02/Fi02 < 200, and intermittent noninvasive ventilation had to be started, and patient’s clinical condition fell into the severe disease category, wherein there was a need to start IV methylprednisolone and to start the therapeutic dose of anticoagulant, i.e., enoxaparin. The D-dimer was greater than 1000 ng/mL therapeutic dose of enoxaparin, i.e., 2 U/kg in two divided doses was started. Patient’s condition improved. In the present case, we fraught with the increased risk of bleeding or mortality subsequent to increasing the dose of anticoagulant as the patient was already on antiplatelets.
Conclusions
We emphasize that one must evaluate the risk and benefit of bleeding vs improved oxygenation prior to considering the therapeutic dose of LMW heparin in patients who are already on antiplatelets. A track on d-dimer and fibrinogen levels for dose titration may be useful step in this set of patients. We reiterate upon the formulation of dogmatic guidelines in this context is warranted.