Thromboembolic and bleeding events in intensive care unit patients with COVID-19: results from a Brazilian tertiary hospital.

OBJECTIVES: To describe the incidence of thromboembolic events in adult patients with severe COVID-19 and identify clinical and laboratory factors associated with these events. DESIGN: Observational retrospective cohort study of 243 adult patients with severe COVID-19 admitted to an intensive care unit (ICU) at a Brazilian tertiary hospital. RESULTS: The incidence of all thromboembolic events was 14.8%, in which 3.8% developed deep vein thrombosis, 7.8% pulmonary embolism, 2.5% acute myocardial infarction, 1.2% stroke, and 1.2% peripheral artery occlusion. Risk factors identified were D-dimer at admission >3000 ng/mL (P=<0.0013) and major bleeding (P=0.001). The cumulative risk of developing thromboembolic events at day 28 after ICU admission was 16.0%. The rate of major bleeding was 4.1%. After receiver operating characteristic curve analysis, the D-dimer cut-off at admission correlating with thromboembolic events was 1140.5 ng/mL. CONCLUSIONS: The rate of thromboembolic events in our study was lower than previously described. High D-dimer level at admission was the leading risk factor; the optimal cut-off was 1140.5 ng/mL. The occurrence of thromboembolic events did not have an impact on the median overall survival rate. The optimal anticoagulant strategy in this context still needs to be established.

Methemoglobinemia and hemolytic anemia after COVID-19 infection without identifiable eliciting drug: A case-report.

We report a second case of methemoglobinemia and non-autoimmune hemolytic anemia after contracting the SARS-CoV-2 infection in the absence of an identifiable eliciting drug. A 35-year old male without previous known comorbidities was admitted after he was diagnosed with the COVID-19 infection and had large pulmonary involvement. Seven days later, he desaturated but was without any signs of respiratory distress. A check of arterial blood gas revealed normal partial pressure of oxygen and follow-up tests confirmed a methemoglobinemia diagnosis. Over the next few days, hemolysis was established after decreased levels of hemoglobin and increased levels of indirect bilirubin and lactate dehydrogenase. A hemolytic anemia investigation panel came back normal, including G6PD. A second G6PD test was ordered at the 5-month follow-up appointment and revealed decreased levels. Clinicians should thus be aware of possible false negative tests when testing for G6PD during hemolytic crisis. In addition, whether the COVID-19 infection alone would be responsible for this chain of events remains a challenging question.