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Comparison of Higher-Than-Standard to D-Dimer Driven Thromboprophylaxis in Hospitalized Patients With COVID-19
Maya R Chilbert1,2, Collin M Clark1,2, Ashley E Woodruff1,2
1University at Buffalo, Buffalo, NY, USA.
Insights
This study compared thromboprophylaxis strategies in hospitalized patients with coronavirus disease 2019. While regimens affected bleeding risk, thrombotic outcomes were similar, suggesting caution with full-dose anticoagulation in ventilated patients.
Area of Science:
- Internal Medicine
- Critical Care Medicine
- Hematology
Background:
- Coronavirus disease 2019 (COVID-19) is associated with a high risk of coagulopathy and thrombotic events.
- Standard thromboprophylaxis may be insufficient in hospitalized COVID-19 patients, necessitating evaluation of alternative strategies.
Purpose of the Study:
- To compare the safety and effectiveness of two thromboprophylaxis strategies in hospitalized COVID-19 patients.
- To assess the impact of different anticoagulation regimens on thrombotic events and bleeding complications.
Main Methods:
- A multicenter, retrospective cohort study involving 153 hospitalized patients with COVID-19.
- Regimen A: higher-than-standard thromboprophylaxis dose. Regimen B: full-dose anticoagulation for D-dimer ≥ 3 mcg/mL, prophylactic otherwise.
- Primary outcome: rate of thrombotic events. Secondary outcomes: bleeding events and 30-day thrombotic events post-discharge.
Main Results:
- No significant difference in thrombotic events between Regimen A (4.7%) and Regimen B (4.5%), P=1.0.
- Bleeding events were significantly higher in Regimen B (13.5%) compared to Regimen A (3.1%), P=0.04.
- All bleeding events occurred in mechanically ventilated patients, mostly on full-dose anticoagulation.
Conclusions:
- Thromboprophylaxis regimens influence bleeding risk but not thrombotic outcomes in hospitalized COVID-19 patients.
- Full-dose anticoagulation should be used cautiously in mechanically ventilated COVID-19 patients without specific indications.
- Further research is needed to optimize anticoagulation strategies for COVID-19-associated coagulopathy.
Abstract:
Introduction: Coronavirus disease 2019 is a global health threat often accompanied with coagulopathy. Despite use of thromboprophylaxis in this population, thrombotic event rates are high. Materials and methods: This was a multicenter, retrospective cohort study comparing the safety and effectiveness of thromboprophylaxis strategies at 2 institutions in hospitalized patients with coronavirus disease 2019. Regimen A utilized a higher-than-standard thromboprophylaxis dosage and Regimen B received full-dose anticoagulation for any D-dimer 3 mcg/mL or greater and prophylactic for less than 3 mcg/mL. The primary outcome compared the rate of thrombotic events between treatment groups. Secondary endpoints compared rates of major or clinically relevant non-major bleeding as well as the proportion of patients in each group experiencing thrombotic events within 30 days of discharge. Results: One-hundred fifty-three patients were included in the analysis, 64 receiving Regimen A and 89 receiving Regimen B. Seven (4.6%) thrombotic events occurred, 3 (4.7%) in patients receiving Regimen A, and 4 (4.5%) in Regimen B (P = 1.0). Twelve patients (13.5%) receiving Regimen B had a bleeding event versus 2 (3.1%) in Regimen A (P = .04), half of which were major in each group. All patients who bled in either treatment group were receiving mechanical ventilation, and 12 of 14 were receiving full-dose anticoagulation. One patient receiving Regimen A was readmitted with a pulmonary embolism. Conclusions: In this study, the thromboprophylactic regimen impacted bleeding, but no significant difference was seen with thrombotic outcomes. Almost all patients who experienced a bleed were mechanically ventilated and receiving full-dose anticoagulation. The use of full-dose anticoagulation should be cautioned in this population without an additional indication.
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