Table 1.

Characteristics of four patients with COVID-19 before ECCO₂R initiation.

	Patient 1	Patient 2	Patient 3	Patient 4*
Demographics
Sex	Male	Male	Male	Male
Age, years	57	74	67	52
Body mass index, kg/m2	29.4	24.3	26.8	42.1
Comorbidities	Hypertension, diabetes	Hypertension, diabetes, CAD, COPD, CKD	Hypertension, diabetes, CAD, CKD	Hypertension, diabetes, COPD, CKD
Clinical characteristics
SAPS II	37	51	54	43
SOFA score	7	9	8	11
ICU length of stay before ECCO2R initiation, days	23	6	25	8
Pre-ECCO2R adjuvant therapy
Prone positioning	Yes	Yes	Yes	Yes
Nitric oxide	Yes	No	Yes	Yes
Duration of ECCO2R, days	6	4	5	8
VT, mL/kg PBW	5.6	7.2	6.5	7.3
RR, breaths/min	30	19	31	21
VE, L/min	10.3	10.1	10.5	13.8
PPLAT, cmH2O	30	26	31	27
PEEP, cmH2O	10	11	6	11
Driving pressure, cmH2O	20	15	25	16
Compliance, mL/mbar	18.4	34.6	18.4	41.2
PaO2/FiO2 ratio	153.3	150.6	160.0	140.0
PaCO2, mmHg	57.4	70.0	56.6	58.7
pH	7.38	7.29	7.41	7.23
Arterial ${\text{HCO}}_{3^{-}}$, mMol/L	33.3	32.3	35.1	21.4
LVEF, %	60	40	65	60
Norepinephrine dose, μg/kg/min	0.002	0.336	0.219	0.038
Laboratory findings
White cell count, g/L	7.1	12.9	26.3	17.1
Total lymphocytes	1.54	0.94	1.94	1.26
Hemoglobin, g/dL	84	95	90	93
Platelet count, giga/L	316	357	288	301
Creatinine, mg/dL†	0.5	1.9	1.0	2.0
Urea, mg/dL‡	37	197	101	230
Lactate dehydrogenase, U/L	311	492	237	365
Alanine aminotransferase, U/L	104	378	40	212
Aspartate aminotransferase, U/L	44	359	35	363
Albumin, g/L	24.9	23.6	29.2	29.7
B-type natriuretic peptide, pg/mL	48	591	93	9
C-reactive protein, mg/L	71.1	164.5	113.9	197.7
Procalcitonin, μg/L	0.5	6.1	7.5	1.6
Interleukin-6, μg/L	74	2150	95	55
Ferritin, μg/L	1588	2107	723	1076
D-dimer, mg/L	3.1	15.3	1.77	3.9

^*Patient received ECCO₂R + CRRT.

^†To convert the values for serum creatinine to mg/dL, multiply by 88.4.

^‡To convert the value for urea to blood urea nitrogen, multiply by 0.467.

CAD, coronary artery disease; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; COVID-19, coronavirus disease 2019; CRRT, continuous renal replacement therapy; ECCO₂R, extracorporeal carbon dioxide removal; FiO₂, fraction of inspired oxygen; ${\text{HCO}}_3^{-}$, bicarbonate; ICU, intensive care unit; LVEF, left ventricular ejection fraction; NA, not applicable/not available; PaCO₂, arterial partial pressure of carbon dioxide; PaO₂, arterial partial pressure of oxygen; PBW, predicted body weight; PEEP, positive end-expiratory pressure; P_PLAT, plateau pressure; RR, respiratory rate; SAP, Simplified Acute Physiology Score; SOFA, Sequential Organ Failure Assessment; V_E, minute volume; V_T, tidal volume.