Table 1.

Patient characteristics

Characteristic	All patients (n = 38)
Median age (range), years	66 (33–91)
Female sex, no. (%)	12 (32%)
COVID-19 interventions, no. (%)
Hydroxychloroquine	26 (68)
Azithromycin	25 (66)
Convalescent plasma	9 (24)
Tocilizumab	6 (16)
Remdesivir	2 (5)
Gimsilumab	2 (5)
Admitted to ICU, no. (%)	27 (71)
Vasopressors, no. (%)	14 (37)
Renal replacement therapy, no. (%)	14 (37)
Oxygen requirement, no. (%)
None	2 (5)
Up to 4 L NC	5 (13)
> 4 L NC, NRB, HFNC	8 (21)
Mechanical ventilation	23 (61)
Median days (range) from COVID-19 diagnosis to plasma hemoglobin collection	15 (1–29)
Mean (standard deviation) change in erythrocyte hemoglobin concentration from hospital admission to date of plasma hemoglobin collection, g/dL	− 3.2 (2.4)
Labs, median (range)
Plasma hemoglobin, mg/dL†	10.8 (1.1–77.1)
< 5 mg/dL, no. (%)	7 (18)
5–15 mg/dL, no. (%)	16 (42)
15–30 mg/dL, no. (%)	6 (16)
> 30 mg/dL, no. (%)	9 (24)
Lactate dehydrogenase, U/L	472 (241–12,254)
Haptoglobin, mg/dL	232 (0–638)
Reticulocyte, %	2.6 (0.8–12.5)
Bilirubin, mg/dL	0.9 (0.3–7.9)

ICU intensive care unit, NC nasal canula, NRB non-rebreather mask, HFNC high-flow nasal cannula

^†Normal is < 5 mg/dL. Values between 5 and 15 mg/dL can result from suboptimal venipuncture