Table 3.
Independent risk factors for postoperative AKI
| Univariate Logistic model a | Multivariate Logistic model b | |||
|---|---|---|---|---|
| OR (95% CI) | P value | OR (95% CI) | P value | |
| Age (y) | 1.022 (1.010–1.034) | < 0.001 | 1.018 (1.004–1.033) | 0.013 |
| History of chronic kidney disease | 4.756 (2.023–11.180) | < 0.001 | – | – |
| Sepsis | 1.869 (1.013–3.451) | 0.046 | – | – |
| Radiocontrast exposure c | 1.797 (1.091–2.961) | 0.021 | 1.843 (1.031–3.293) | 0.039 |
| Baseline creatinine (umol/L) d | 1.011 (1.005–1.017) | < 0.001 | 1.016 (1.008–1.025) | < 0.001 |
| Preoperative Hb (g/L) e | 0.990 (0.983–0.997) | 0.004 | – | – |
| Preoperative albumin < 37.5 g/L e | 2.277 (1.624–3.194) | < 0.001 | 1.892 (1.238–2.891) | 0.003 |
| ASA classification | 1.966 (1.472–2.625) | < 0.001 | 1.719 (1.193–2.477) | 0.004 |
| Open surgery | 1.792 (1.213–2.650) | 0.003 | – | – |
| Emergency surgery | 2.284 (1.349–3.869) | 0.002 | ||
| General surgery f | 1.582 (1.133–2.208) | 0.007 | – | – |
| Duration of surgery (every 1 h increase) | 1.047 (0.976–1.124) | 0.202 | – | – |
| Intraoperative use of vasopressors g | 1.660 (1.146–2.404) | 0.007 | 1.680 (1.065–2.648) | 0.026 |
| Non-renal SOFA within 24 h ICU admission | 1.133 (1.044–1.230) | 0.003 | – | – |
ASA American Society of Anesthesiologists, CI confidence interval, Hb hemoglobin, OR odds ratio, SOFA sequential organ failure assessment score
a Perioperative variables with P < 0.10 in the univariate analyses by independent samples t test, Mann-Whitney U test, chi-squared test, or Fisher’s exact test were included, except preoperative BNP, duration of anesthesia, and postoperative minimal Hb before AKI because of collinearity
b Backward: LR
c Including patients who had radiocontrast exposure within 7 days before surgery
d Determined by the minimal value of serum creatinine measured within 3 months before admission and in hospital before surgery; if neither value was available, the modification of diet in renal disease formula was adopted to estimate the baseline serum creatinine according to the Kidney Disease Improving Global Outcomes guideline
e Measured within 3 days before surgery
f Abdominal surgery, such as gastrointestinal, hepatobiliary, and pancreatic surgery
g Including use of phenylephrine, norepinephrine, epinephrine, and dopamine