Table 2.

Characteristics of intermittent hemodialysis sessions

	All	First	Later	P
Number of sessions	211	72	139
Number of days since ICU admission	8 [3–12]	3 [2–5]	10 [7–15]	< 0.0001
SOFA score (without renal points)	6 [2–11]	8 [4–13]	4 [1–9]	0.0001
Organ support therapy at T0
Invasive mechanical ventilation	130 (62%)	48 (67%)	82 (59%)	0.30
Vasopressors	90 (43%)	44 (61%)	46 (30%)	0.0001
Norepinephrine	80 (38%)	36 (50%)	44 (32%)
Epinephrine	10 (5%)	8 (11%)	2 (1%)
Cardiovascular SOFA score ≥ 1 at T0	104 (49%)	48 (67%)	56 (40%)	0.0003
Tissue perfusion parameters at T0
Lactate > 2 mmol/L	49 (23%)	33 (46%)	16 (12%)	< 0.0001
Index capillary refill time ≥ 3 s	38 (18%)	23 (32%)	15 (11%)	0.0003
Hemodialysis settings
Duration (hours)	4 [4–4]	4 [4–4]	4 [4–5]	0.015
Ultrafiltration	135 (64%)	25 (35%)	110 (79%)	< 0.0001
Volume of ultrafiltration (L)	2.5 [2.0–3.0]	2.0 [1.6–3.0]	2.6 [2.0–3.1]	0.10
Intradialytic hemodynamic instability	48 (23%)	31 (43%)	17 (12%)	< 0.0001
Timing of first hemodynamic instability				0.092
Before first hour	35 (73%)	24 (77%)	4 (24%)
Between first and second hour	6 (13%)	3 (10%)	1 (6%)
Between second and fourth hour	7 (14%)	4 (13%)	3 (18%)
Therapeutic interventions (not exclusive)
Increase in vasopressors	35 (73%)	24 (77%)	11 (65%)
Fluid administration	15 (31%)	13 (42%)	2 (12%)
Initiation of vasopressors	7 (15%)	5 (16%)	2 (12%)
Decrease in ultrafiltration	3 (6%)	0	3 (18%)
Cessation of ultrafiltration	3 (6%)	0	3 (18%)

Quantitative variables are expressed as median [25–75th percentiles] and qualitative variables as number (%)