BCHE and COVID-19: Critically ill COVID-19 patients on vvECMO support on day 1 (n = 39) demonstrated an even more pronounced BChE activity reduction compared to healthy controls (healthy volunteers: 2.966 U/l (2.710–3.236) vs. critically ill COVID-19 patients on vvECMO support: 1.264 U/l (917–1.456), p < 0.05; Figure 1B).