BCHE and COVID-19: Compared to previously reported BChE activity levels in healthy volunteers (n = 40) [18], critically ill COVID-19 patients (n = 52) showed a significantly reduced BChE activity within 24 h following ICU admission (=day 1) (BChE activity is shown as median and interquartile range (IQR); healthy volunteers: 2.966 U/l (2.710–3.236) vs. critically ill COVID-19 patients: 1.311 U/l (941–1.629), p < 0.05; Figure 1A).