Mortality and morbidity of low-grade red blood cell transfusions in septic patients: a propensity score-matched observational study of a liberal transfusion strategy

Annals of Intensive Care

Table 3 Main outcome variables

Outcome	Propensity-matched groups		Relative risk (95% CI^a)	Absolute risk increase (95% CI)	P^b
Outcome	Control n = 237	RBC^cn = 237
90-day mortality	80 (34)	102 (43)	1.28 (1.01–1.61)	9.3% (0.6–18%)	0.032
180-day mortality	91 (38)	116 (49)	1.27 (1.04–1.57)	11% (1.7–19%)	0.018
RRT^d	21 (8.9)	48 (20)	2.29 (1.41–3.69)	11% (5.1–18%)	0.001
AKIN	0 (0–2)	0 (0–3)			0.001
DAF^e of RRT	28 (16–28)	28 (9–28)			0.29
DAF of vasopressors	26 (13–27)	23 (7–26)			0.009
DAF of mechanical ventilation	26 (12–28)	21 (4–27)			0.002
SOFA max^f	9 (7–12)	11 (8–13)			< 0.001

Data are presented as number (%) or median (interquartile range)
^aConfidence interval
^bWilcoxon rank sum or McNemar´s test
^cLow-grade red blood cell transfusion defined as < 670 ml any of the first 5 days
^dRenal Replacement Therapy
^eDays Alive and Free
^fSequential Organ Failure Assessment score the first 10 days after admission