COV1: Cannula-Associated Deep Vein Thromboses are Prevalent in COVID-19 Veno-venous Extracorporeal Membrane Oxygenation Patients

Abstract

Background: Patients with severe COVID-19 related respiratory failure may require veno-venous extracorporeal membrane oxygenation (VV ECMO). After decannulation, patients on VV ECMO have historically had high percentages of cannula-associated deep vein thrombosis (CaDVT). Due to their hypercoagulable state and prolonged course on VV ECMO, we hypothesized that patients with COVID-19 would experience a higher rate of CaDVT when compared to their non-COVID-19 counterparts. We also described the association between location and size of cannula in the development of CaDVTs. Methods: This was a single center retrospective review of patients ≥ 18 years old who were treated with VV ECMO and decannulated from January 1, 2014, to January 10, 2022. Patients who were placed on VV ECMO due to trauma and patients who were cannulated for veno-arterial ECMO were excluded. Patients were managed in a dedicated Lung Rescue Unit and anticoagulated with a heparin infusion at a goal partial thromboplastin time (aPTT) of 45-55 or 60-80 depending on the presence of clotting complications. Post-decannulation venous duplexes were performed 24 hours after decannulation and if positive for DVT, performed again in 2 weeks. Univariate and multivariate analyses were conducted to analyze our primary outcome of the development of CaDVT. Results: A total of 291 patients met our inclusion criteria: 76 COVID-19 VV ECMO patients and 215 non-COVID-19 VV ECMO patients. Decannulated COVID-19 VV ECMO patients had a significantly higher body mass index (BMI) (35.8, 32.9, p= 0.03) and length of ECMO run (hours) (660, 312, p< 0.001) than their non-COVID-19 counterparts. Most decannulated patients in both groups received post-decannulation duplexes (96%, 99%, p= 0.45). COVID-19 and non-COVID-19 patients decannulated from VV ECMO both experienced high incidences of CaDVT on initial post-decannulation ultrasound (95%, 88%, p= 0.13). COVID-19 patients were more likely to have multiple CaDVTs (32%, 11%, p< 0.001). Patients with COVID-19 experienced a higher rate of right common femoral CaDVT (47%, 17%, p< 0.001) and a higher percentage of 25 French drainage cannula CaDVT (48%, 18%, p< 0.001). COVID-19 VV ECMO patients had a significantly higher incidence of persistent CaDVT on repeat ultrasound (78%, 56%, p= 0.03). A logistic regression was performed with all decannulated patients. Age, BMI, hours on ECMO, COVID-19 status, and size and location of ECMO cannulas did not predict the presence of DVT. Conclusion: Both COVID-19 and non-COVID-19 VV ECMO patients had high rates of CaDVTs. The utilization of VV ECMO in COVID-19 respiratory failure was associated with a higher incidence of CaDVTs on repeat ultrasound as compared to patients with non-COVID-19 related respiratory failure. Regular post-decannulation screening, treatment, and follow up imaging should be performed. Further investigation into the effect of anticoagulation strategy is needed.