Table 2.
Cause-specific Cox proportional hazards models for time to composite outcome of any stage AKI or RRT and each marker of hemolysis
| Covariate | Model 1: Plasma-Free Hemoglobin (mg/dl) (Ref: Unmeasured Value) |
Model 2: LDH (U/L) (Ref: Unmeasured Value) |
Model 3: Minimum Platelets (per 100/ul) | Model 4: Minimum Hemoglobin (per 1 g/dl) | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| HR (95% CI) | P | HR (95% CI) | P | HR (95% CI) | P | HR (95% CI) | P | |||
| Hemolysis marker | <50 | 1.12 (0.26 to 4.81) | 0.88 | <2500 | 0.78 (0.19 to 3.24) | 0.73 | 0.96 (0.93 to 1.00) | 0.06 | 0.96 (0.89 to 1.04) | 0.30 |
| >50 | 2.86 (1.44 to 5.66) | <0.01 | >2500 | 3.07 (1.72 to 5.48) | <0.01 | |||||
| Agea (ref: <1 mo) | 0.02 | <0.01 | <0.01 | 0.03 | ||||||
| 1 mo to 1 yr | 1.63 (1.01 to 2.64) | 1.60 (0.99 to 2.59) | 1.67 (1.03 to 2.71) | 1.62 (1.00 to 2.63) | ||||||
| >1–5 yr | 1.42 (0.82 to 2.44) | 1.40 (0.81 to 2.39) | 1.57 (0.91 to 2.72) | 1.42 (0.82 to 2.46) | ||||||
| >5–12 yr | 1.96 (1.01 to 3.80) | 1.90 (0.98 to 3.67) | 2.37 (1.21 to 4.64) | 1.92 (0.98 to 3.75) | ||||||
| >12–18 yr | 3.02 (1.60 to 5.73) | 3.26 (1.75 to 6.09) | 3.41 (1.77 to 6.56) | 2.99 (1.56 to 5.72) | ||||||
| >18 yr | 2.49 (1.04 to 5.99) | 2.67 (1.11 to 6.40) | 2.66 (1.10 to 6.41) | 2.41 (0.98 to 5.92) | ||||||
| Male sex (versus female) | 1.15 (0.88 to 1.49) | 0.31 | 1.15 (0.88 to 1.50) | 0.29 | 1.14 (0.87 to 1.49) | 0.34 | 1.17 (0.90 to 1.52) | 0.25 | ||
| Hospital unit/ECMO mode (ref: CICU) | <0.01 | <0.01 | <0.01 | <0.01 | ||||||
| NICU/VV | 0.29 (0.14 to 0.59) | 0.29 (0.14 to 0.61) | 0.28 (0.13 to 0.60) | 0.30 (0.14 to 0.62) | ||||||
| NICU/VA | 0.41 (0.27 to 0.61) | 0.41 (0.27 to 0.62) | 0.42 (0.28 to 0.64) | 0.41 (0.27 to 0.62) | ||||||
| PICU/VV | 1.15 (0.66 to 2.02) | 1.16 (0.66 to 2.04) | 1.25 (0.71 to 2.22) | 1.18 (0.67 to 2.09) | ||||||
| PICU/VA | 1.83 (1.03 to 3.26) | 1.78 (1.00 to 3.16) | 1.77 (0.99 to 3.17) | 1.75 (0.98 to 3.12) | ||||||
| Abnormal Cr ECMO start | 0.77 (0.55 to 1.09) | 0.14 | 0.75 (0.53 to 1.06) | 0.10 | 0.75 (0.53 to 1.06) | 0.10 | 0.78 (0.55 to 1.11) | 0.17 | ||
| Average pH | 0.37 (0.04 to 3.28) | 0.37 | 0.40 (0.04 to 3.59) | 0.41 | 0.38 (0.04 to 3.99) | 0.42 | 0.40 (0.05 to 3.57) | 0.41 | ||
| Average lactate | 1.12 (1.07 to 1.16) | <0.01 | 1.11 (1.07 to 1.16) | <0.01 | 1.11 (1.07 to 1.16) | <0.01 | 1.11 (1.07 to 1.16) | <0.01 | ||
| Median MAPb | 0.99 (0.97 to 1.00) | 0.10 | 0.99 (0.97 to 1.00) | 0.10 | 0.99 (0.97 to 1.00) | 0.12 | 0.99 (0.97 to 1.00) | 0.09 | ||
| Nephrotoxic medication countc | 1.03 (0.85 to 1.23) | 0.79 | 1.04 (0.87 to 1.25) | 0.69 | 1.02 (0.85 to 1.23) | 0.84 | 1.03 (0.86 to 1.24) | 0.77 | ||
CI, confidence interval; CICU, cardiac intensive care unit; ECMO, extracorporeal membrane oxygenation; HR, hazard ratio; LDH, lactate dehydrogenase; MAP, mean arterial pressure; NICU, neonatal patients in the intensive care unit; NINJA, Nephrotoxic Injury Negated by Just-in-Time Action; PICU, pediatric intensive care unit; VA, venoarterial; VV, venovenous.
a
Age at time of ECMO start.
b
MAP (mean arterial pressure).
c
On the basis of the NINJA list of nephrotoxins.