Table 4. Supplemental Multivariable Logistic Regression Results and Predictors of Acute Kidney Injury Following Colorectal Surgery
Odds Ratio
(95% CI) p-value Patient Factors
Male 1.51 (0.94 - 2.43) 0.09
Age (years) 1.21 (0.98 - 1.49) 0.08
Race (ref = White) 0.54
Asian <0.01 (<0.01 - >99.99)
Black 1.60 (0.78 - 3.30)
Unknown 1.87 (0.39 - 8.94)
BMI (kg/m2) 1.01 (0.98 - 1.05) 0.51
Diabetes 0.78 (0.40 - 1.57) 0.50
Hypertension 2.47 (1.42 - 4.27) 0.001
Renal insufficiency 0.77 (0.37 - 1.61) 0.49
Functional status (ref = Independent) 0.03
Partially dependent 1.10 (0.38 - 3.14)
Totally dependent 12.98 (1.98 - 85.19)
ASA classification (ref = ASA 2) 0.10
ASA 1 <0.01 (<0.01 - >99.99)
ASA 3 0.99 (0.59 - 1.67)
ASA 4 4.25 (1.26 - 14.26)
Procedural Factors
Diverticular disease 1.29 (0.64 - 2.58) 0.48
Open surgery 2.99 (1.54 - 5.81) 0.001
Ileostomy 1.39 (0.82 - 2.37) 0.22
Wound class (ref = Clean/contaminated) 0.56
Clean <0.01 (<0.01 - >99.99)
Contaminated 1.60 (0.84 - 3.07)
Dirty/infected 1.28 (0.48 - 3.39)
Procedure type (ref = Partial colectomy) 0.39
Total colectomy 2.15 (0.66 - 6.95)
Proctocolectomy 0.48 (0.10 - 2.46)
Rectal 1.14 (0.59 - 2.19)
Ureteral stent 1.91 (1.05 - 3.45) 0.03
Complication(s) 0.90 (0.54 - 1.49) 0.69
NSAIDs 2.30 (1.38 - 3.83) 0.002
Intraoperative hypotension 2.18 (1.07 - 4.41) 0.03
Intraoperative vasopressor 1.12 (0.60 - 2.09) 0.71
EBL >500 mL 1.18 (0.65 - 2.13) 0.59
OR time >200 minutes 2.20 (1.22 - 3.98) 0.009
IVF POD 0 (mL) 1.03 (0.92 - 1.15) 0.59
IVF POD 1 (mL) 1.30 (1.10 - 1.54) 0.002
UOP POD 0 (mL) 0.88 (0.60 - 1.29) 0.51
UOP POD 1 (mL) 0.82 (0.64 - 1.03) 0.09
C-statistic = 0.84
*Complication(s) does not include acute kidney injury.
BMI=Body mass index; ASA Classification=American Society of Anesthesiologists Physical Status classification;
NSAIDs=Nonsteroidal anti-inflammatory drugs; EBL=Estimated blood loss; OR=Operating room; IVF=Intravenous fluid; POD=Postoperative day; UOP=Urine output
