Table 2.

Predictive risk model for 60-day mortality in critically ill patients with AKI requiring dialysis^a

Parameter	Coefficient	OR	P-value
Chronic health condition
Age (per year)	0.04	1.04	<0.01
Chronic hypoxemia	0.73	2.07	0.07
Cardiovascular diseaseb	0.27	1.31	0.03
Malignancyc	0.99	2.68	<0.01
Immunosuppressive therapyd	−0.44	0.65	0.02
Present illness
Ischemic AKI	0.16	1.17	<0.05
Postsurgery	−0.45	0.64	0.08
At RRT initiation
Heart rate (beats/min)e	0.01	1.007	<0.03
Mean arterial pressure (mmHg)e	−0.02	0.983	<0.02
Urine volume (mL/day)e,f	−0.14	0.867	0.02
Mechanical ventilation	1.03	2.793	<0.01
FiO2≥0.6e	3.07	21.6	<0.01
Interaction of mechanical ventilation & FiO2 ≥0.60g	−1.53	0.216	<0.01
Arterial pHe	−2.64	0.07	0.06
Arterial oxygen partial pressure (mmHg)e,f	−0.66	0.52	<0.05
Serum creatinine (mg/dl)	−0.18	0.834	0.01
Serum bicarbonate (mmol/L)e	−0.03	0.968	0.02
Serum phosphate (mg/dl)e	0.02	1.05	0.05
Serum albumin (g/dl)e	−0.34	0.710	0.02
Total bilirubin (mg/dl)f	0.36	1.439	<0.01
INRe,f	0.54	1.719	0.01
Platelet count (k/μl)f	−0.36	0.695	<0.01

AKI, acute kidney injury; RRT, renal replacement therapy; FiO₂, fraction of inspired oxygen; INR, international normalized ratio; OR, odds ratio; CI, confidence interval.

^aMultivariable logistic regression was used to derive model coefficients.

^bHistory of angina, documented myocardial infarction, or congestive heart failure.

^cSolid tumor with or without metastases, leukemia, or lymphoma.

^dPositive HIV status, AIDS, nonrenal organ transplantation, or immunosuppressive therapy.

^eWithin 24 hours of RRT initiation.

^fLog-transformed variable.

^gDue to negative interaction, the risk of mortality in a mechanically ventilated subject with FiO₂ ≥0.60 is lower compared to a non-ventilated subject with FiO₂ ≥0.60, and higher compared to a ventilated subject with FiO₂ <0.60.