SARS-CoV-2 Does Not Spread Through Extracorporeal Membrane Oxygenation or Dialysis Membranes

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a major worldwide health threat in just a few weeks. ICU admission and the recourse to extracorporeal organ support, such as continuous renal replacement therapy (CRRT) or venovenous extracorporeal membrane oxygenation (VV-ECMO) may be needed in the most severe forms of the disease. Because SARS-CoV-2 viremia has been reported in some cases, it has been hypothesized that this small virus (average size of 125 nm) could pass through polymethylpentene ECMO membranes or acrylonitrile/sodium methallylsulfonate CRRT membranes. In this study, we investigated whether SARS-CoV-2 RNA was detected in the dialysis effluent fluid or in the condensate collected from the ECMO membrane exhalation port (gas outlet) when the virus was present in the lower respiratory tract and the plasma.

To the best of our knowledge, this is the first study that investigated the risks for SARS-CoV-2 dissemination through membranes used for extra corporeal organ support in critically ill patients. Though a recent report revealed that SARS-CoV-2 is almost always present in the lower respiratory tract, sometimes in the feces but never in urine samples, our findings are reassuring regarding the risk of contamination for ICU professionals when treating patients on VV-ECMO or CRRT. Specifically, our findings do not support the routine use of a viral filter on the exhaust of the commonly used polymethylpentene-based ECMO membrane lungs. Prevention and education of healthcare workers should therefore remain focused on limiting the risks of virus spreading during invasive respiratory procedures, such as high-flow oxygenation, mouth care, intubation, or microbiological sampling of nasopharyngeal, tracheal, or bronchioalveolar secretions. The number of patients with CRRT (n = 8) is limited, but the fact that SARS-CoV-2 PCR was negative in all dialysis effluent is somehow reassuring. Lastly, we cannot rule out that longer ECMO runs could progressively lead to membrane alteration, plasma leakage, and ultimately SARS-CoV-2 aerosolization. However, we purposely chose to investigate the risk of virus spreading within 48 hours after ECMO and CRRT initiation as the viral load—if present in the plasma—is expected to progressively decline afterward. Though our findings may not alter practices, they may contribute to address legitimate interrogations raised by caregivers and reinforce adhesion and trust into infection control measure policies, which is likely to play a major role against the outbreak spreading.