Table 2.

Individual time course of operational characteristics, blood gas, ventilatory, and hemodynamic parameters during ECCO₂R.

	Patient 1					Patient 2					Patient 3					Patient 4*
Operational characteristics	Baseline	1 h	4 h	24 h	48 h	Baseline	1 h	4 h	24 h	48 h	Baseline	1 h	4 h	24 h	48 h	Baseline	1 h	4 h	24 h	48 h
Blood flow, mL/min	400	400	400	400	400	400	400	400	400	400	400	400	400	400	400	200	200	200	200	200
Sweep gas flow, L/min	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	3.5	3.5	3.5	3.5	3.5
CRRT ultrafiltration rate, mL/h	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	0	0	0	0	100†
CRRT effluent rate, mL/kg/h	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	25	25	25	25	25
aPTT, s	30	NA	67	98	93	48	80	79	79	NA	85	NA	NA	56	65	27	26	NA	26	25‡
Blood gas parameters
Arterial
PaCO2, mmHg	57.4	43.5	43.0	38.3	42.4	70.0	50.0	54.7	53.1	52.8	56.6	42.1	42.6	42.4	46.5	58.7	46.5	46.8	47.2	46.3
pH	7.38	7.48	7.48	7.53	7.47	7.29	7.44	7.38	7.39	7.35	7.41	7.53	7.51	7.50	7.47	7.23	7.30	7.36	7.38	7.40
PaO2, mmHg	69.2	63.0	71.0	71.0	66.0	68.0	66.0	69.0	74.0	62.0	80.0	65.0	79.0	82.0	79.0	77.0	81.0	89.0	71.0	94.0
${\text{HCO}}_{3^{-}}$, mMol/L	33.3	32.0	31.6	31.9	30.8	32.3	33.1	32.3	32.4	28.1	35.1	34.6	33.8	33.0	33.3	21.4	21.9	25.9	27.2	27.8
BE, mMol/L	7.6	8.3	7.9	8.7	6.9	4.8	8.2	6.2	6.6	2.5	9.4	10.8	10.2	9.1	8.9	−5.5	−3.9	0.8	2.3	3.0
Pre-ECCO2R
PCO2, mmHg	NA	54.2	53.2	42.5	55.9	NA	58.3	57.0	55.1	52.8	NA	52.4	50.0	51.2	54.0	NA	49.8	41.4	44.5	48.7
${\text{HCO}}_{3^{-}}$, mMol/L	NA	33.9	33.2	33.4	31.8	NA	34.5	31.4	30.6	25.7	NA	33.5	34.7	35.0	35.7	NA	20.7	24.9	27.2	28.7
BE, mMol/L	NA	8.4	7.9	9.6	6.2	NA	8.6	8.0	7.2	0.0	NA	12.0	12.0	10.0	10.5	NA	−5.9	0.5	2.6	3.6
Post-ECCO2R
PCO2, mmHg	NA	15.0	13.4	14.1	18.6	NA	14.3	12.5	13.6	11.9	NA	8.2	10.7	12.4	15.7	NA	7.6	9.5	11.3	8.5
${\text{HCO}}_{3^{-}}$, mMol/L	NA	32.3	29.5	30.3	27.4	NA	27.2	25.6	26.3	24.6	NA	29.0	34.9	28.5	29.9	NA	9.6	15.8	17.0	17.1
BE, mMol/L	NA	8.3	10.5	11.1	7.4	NA	10.2	7.7	7.9	0.2	NA	11.4	11.1	11.2	11.2	NA	−9.5	−1.8	−1.1	0.6
Ventilator parameters
VT, mL/kg PBW	5.6	5.6	5.3	5.3	5.2	7.2	7.2	7.4	6.3	6.4	6.5	5.9	5.6	4.4	4.9	7.3	7.4	7.4	7.2	7.0
RR, breaths/min	30	30	28	26	24	19	19	18	18	18	31	30	30	30	26	21	21	21	21	21
VE, L/min	10.3	10.6	10.8	10.7	7.5	10.1	9.5	9.2	8.6	9.4	10.5	11.5	10.0	9.2	6.2	13.8	13.8	13.9	13.7	13.4
PPLAT, cmH2O	30	30	29	22	22	26	26	25	24	24	31	31	31	30	28	27	27	27	26	25
PEEP, cmH2O	10	10	9	8	8	11	11	11	11	11	6	6	6	6	6	11	11	11	11	11
Driving pressure, cmH2O	20	20	20	14	14	15	15	14	13	13	25	25	25	24	22	16	16	16	15	14
Compliance, mL/mbar	18.4	18.5	17.5	24.9	24.5	34.6	32.5	27.1	33.2	31.4	18.4	15.8	14.3	13.7	13.6	41.2	41.4	41.5	43.5	45.6
PaO2/FiO2 ratio	153.3	153.3	157.8	157.8	165.0	150.6	132.7	153.3	160.0	157.8	160.0	130.0	143.6	136.7	134.0	140.0	147.3	161.8	157.8	175.1
Hemodynamic parameters
Mean arterial pressure, mmHg	71	74	74	76	75	64	89	82	69	66	79	79	77	74	66	63	62	66	67	77
Heart rate, beats/min	93	83	84	92	78	70	58	66	72	70	105	95	92	90	88	84	83	76	72	86
Norepinephrine dose, μg/kg/min	0.002	0.002	0.002	0.002	0.002	0.336	0.336	0.420	0.428	0.430	0.219	0.274	0.192	0.205	0.207	0.038	0.038	0.038	0.038	0.038

^*Patient received ECCO₂R + CRRT.

^†CRRT ultrafiltration was started at 38 h post-ECCO₂R initiation.

^‡ECCO₂R + CRRT was performed with regional citrate anticoagulation.

aPTT, activated partial thromboplastin time; BE, base excess; COVID-19, coronavirus disease 2019; CRRT, continuous renal replacement therapy; ECCO₂R, extracorporeal carbon dioxide removal; FiO₂, fraction of inspired oxygen; ${\text{HCO}}_{3^{-}}$, bicarbonate; PaCO₂, arterial partial pressure of carbon dioxide; PCO₂, venous partial pressure of carbon dioxide; PaO₂, arterial partial pressure of oxygen; PBW, predicted body weight; PEEP, positive end-expiratory pressure; P_PLAT, plateau pressure; RCA, regional citrate anticoagulation; RR, respiratory rate; NA, not applicable/not available; V_E, minute volume; V_T, tidal volume.