RCM balance in patients for whom the hematocrit was or was not consistently raised for RCE during COVID-19. (A) Average RCM balance (mL/kg) per RCE in patients pre–COVID-19 (n = 50) and for whom the hematocrit was consistently raised (↑ Hct, n = 11) or not (↔ Hct, n = 20) during COVID-19. (B) Cumulative RCM (mL/kg) balance and number of procedures per patient in which the hematocrit was raised consistently (• represents individual patients, n = 11).