BACKGROUND: Thrombocytopenia is a recognized risk factor for bleeding during extracorporeal membrane oxygenation (ECMO). This study determines the incidence, risk factors, and clinical relevance of thrombocytopenia and platelet transfusions during venovenous (VV) ECMO. METHODS: The multicenter, prospective observational PROTECMO study included 652 adult patients who received VV ECMO for respiratory failure. Thrombocytopenia was classified as mild (100-149·109/L), moderate (50-99·109/L), or severe (< 50·109/L). Bleeding events were evaluated using a modified Bleeding Academy Research Consortium score. Cox proportional hazards and logistic regression analyses were done to identify predictors, and quantify the association between platelet counts and bleeding risk. RESULTS: A total of 182 patients (27.9%) had thrombocytopenia at baseline (mild in 14.7%, moderate in 8.7%, and severe in 4.4%). Thrombocytopenia during ECMO, at least once in 80.2% of patients, was mild in 21.3% of cases, moderate in 32.2%, and severe in 26.7%. A 10·109/L decrease in platelet count was associated with a 3.7% (95% CI: 2.4-5.0%) increase in risk of bleeding. There was no strong evidence of nonlinear relationship within the platelet count range between 25,000 and 300,000. This relation remained consistent across all ECMO weeks. Mild thrombocytopenia increased the risk of experiencing a bleeding event by 61% (hazard ratio (HR) 1.611, 95% CI 1.230-2.109, p = 0.0005), while moderate and severe thrombocytopenia increased the risk by roughly 90% (moderate: HR 1.944 (CI 1.484-2.545), p < 0.0001; severe: HR 1.876 (CI 1.275-2.7680), p = 0.0014). The risk for thrombocytopenia < 100·109/L during ECMO significantly increased with ICU days prior to ECMO start, postoperative admission, immunocompromised state, renal replacement therapy, septic shock, low hemoglobin, and circuit exchange. CONCLUSIONS: Thrombocytopenia is highly prevalent in VV ECMO, and associated with a significant increase in the risk of bleeding, and a reduction in 6-month survival, particularly at platelet counts below 100·109/L. Further research is needed to better define the outcomes associated with specific thresholds for transfusion of platelets.

• Keywords
• Anticoagulation, Bleeding, Intensive care, Platelet kinetics, Predictors, Thrombocytopenia, VV ECMO,
• MeSH
• Adult MeSH
• Incidence MeSH
• Hemorrhage etiology   epidemiology   MeSH
• Middle Aged MeSH
• Humans MeSH
• Extracorporeal Membrane Oxygenation * adverse effects   methods   MeSH
• Platelet Count methods   MeSH
• Prospective Studies MeSH
• Risk Factors MeSH
• Aged MeSH
• Platelet Transfusion MeSH
• Thrombocytopenia * epidemiology   etiology   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Multicenter Study MeSH
• Observational Study MeSH

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is a life-saving treatment for respiratory failure that may serve as a bridge to patient recovery or lung transplantation. In COVID-19, recovery is somewhat unpredictable and occasionally occurs after >100 days on VV-ECMO support. Thus, determining therapy cessation may be difficult. We report the case of a 59-year-old male without specific risk factors admitted to a tertiary center for rapidly progressive respiratory failure due to severe COVID-19, despite aggressive mechanical ventilatory support. Immediate insertion of VV-ECMO was associated with prompt resolution of hypoxemia and hypercapnia; however, all therapeutic efforts to wean the patient from VV-ECMO failed. During the prolonged hospitalization on VV-ECMO, sepsis was the most life-threatening complication. The patient overcame roughly 40 superinfections, predominantly affecting the respiratory tract, and spent 183 days on antimicrobial treatment. Although the function of other organ systems was generally stable, gradually progressive right ventricular dysfunction due to precapillary pulmonary hypertension required increasing doses of inotropes. A successful lung transplantation was performed after 207 days of VV-ECMO support. The present case provides evidence for prolonged VV-ECMO therapy as a bridge to lung transplantation in severe COVID-19 despite numerous, predominantly infectious complications.

• Keywords
• acute respiratory distress syndrome, coronavirus disease, extracorporeal membrane oxygenation, lung transplant, sepsis,
• Publication type
• Journal Article MeSH
• Case Reports MeSH