Observational Study
Copyright ©The Author(s) 2023.
World J Clin Cases. Jun 6, 2023; 11(16): 3791-3801
Published online Jun 6, 2023. doi: 10.12998/wjcc.v11.i16.3791
Table 1 Baseline demographic and clinical characteristics in all patients and according to acute kidney injury status
Total population (%)N = 206
AKI
No AKI
P value
206 (100)
55 (26.7)
151 (73.3)
Baseline pre-operative characteristics
Gender, female62 (30.1)13 (23.6)49 (32.5)0.236
Age (yr)70 (59-76)74 (59–79)68.5 (59–74)0.039
BMI (kg/m2)27.8 (25.2-31.3)27.0 (24.8–30.0)28.1 (25.4–31.5)0.308
EuroScore II (%)1.7 (1.09-2.9)2.54 (1.52–4.4)1.54 (0.94–2.4)0.0001
Hb (gr/dL)10.3 (9.6-11)10.3 (9.8–10.9)10.2 (9.5–11.0)0.603
WBC (×103/μL)10.3 (7.9-13.1)11.4 (8.9–13.7)9.5 (7.5–12.8)0.015
Creatinine (mg/dL)0.9 (0.8-1.1)1.0 (0.9–1.3)0.9 (0.8–1.1)0.009
CKD50 (24.3)22 (40)28 (18.5)0.003
eGFR (mL/min/1.73 m2)79.1 (60.2-89.9)69.1 (52.3-84.2)81.3 (63.1-90.8)0.007
PPC5 (2.4)1 (1.8)4 (2.6)1.0
ICD5 (2.4)4 (7.3)1 (0.7)0.019
PAD10 (4.9)4 (7.3)6 (4)0.462
Thyroid disease36 (17.5)7 (12.7)29 (19.2)0.309
Stroke3 (1.5)1 (1.8)2 (1.3)1.0
Intraoperative characteristics
CPB (Extracorporeal circulation)198 (96.1)51 (92.7)147 (97.4)0.214
Duration of CPB (min), Ν = 198112 (84-145) 121 (104–171)106 (80–141)0.009
Aortic cross-clamp time (min), Ν = 19389 (59-108) 87 (67–111)77 (56–107)0.067
Duration of general anesthesia in surgery (min)240 (190-300) 273 (213–350)229 (183–300)0.016
CABG116 (56.3)29 (52.7)87 (57.6)0.634
Heart valve repair7 (3.4)1 (1.8)6 (4)0.678
Aortic valve replacement71 (34.5)20 (36.4)51 (33.8)0.743
Mitral valve replacement15 (7.3)4 (7.3)11 (7.3)1.0
Tricuspid valve replacement7 (3.4)2 (3.6)5 (3.3)1.0
Mixed valve replacement10 (4.9)2 (3.6)8 (5.3)1.0
Aneurysm repair23 (11.2)5 (9.1)18 (11.9)0.803
Acute aortic dissection4 (1.9)3 (5.5)1 (0.7)0.059
Heart transplant4 (1.9)3 (5.5)1 (0.7)0.059
Post-operative characteristics
Duration of mechanical ventilation (min)780 (591-1198)1113 (777–2195)714 (511–1020)0.0001
Duration of sedation in ICU (min)360 (250-600) 540 (300–810)300 (240–480)0.0001
Duration of sedation during and post surgery (min)593 (480-842) 754 (540–1245)570 (476–740)0.0001
Fluid balance 24 h post surgery (mL)722 (70-1418) 1090 (330–1862)501 (11–1150)0.001
Fluid balance 48 h post surgery (mL), (N = 146)N (%); 146 (70.9)46 (31.5)100 (68.5)0.526
-202 [(-1146) - 377]-163 [(-1186) – 531]-248 [(-1099) – 296]
Systolic blood pressure (mmHg)119 (105-135)116 (103 – 134)120 (108–135)0.162
Diastolic blood pressure (mmHg)61 (55-70)58 (54–65)63 (55–70)0.015
Mean arterial blood pressure (mmHg)80 (71-88)75 (68–84)80 (74–89)0.005
Vasopressors65 (31.6)27 (49.1)38 (25.2)0.002
Inotropes130 (63.1)41 (74.5)89 (58.9)0.05
Table 2 Univariate logistic regression analysis for acute kidney injury development
Variable
Exp (B)
95%CI
P value
Preoperative characteristics
Female sex0.640.32–1.310.224
Age1.020.99–1.050.125
BMI0.980.92–1.050.601
EuroScore II1.211.08–1.340.001
Hb1.010.76–1.340.948
WBC1.01.0–1.00.014
Creatinine1.50.76–2.960.246
HTN0.860.4–1.850.699
Diabetes0.910.47–1.750.777
CKD2.931.49–5.770.002
CAD1.020.53–1.960.959
CHF0.120.01–1.140.64
PCP1.470.16–13.440.733
PAD0.530.14–1.950.337
Thyroid disease1.630.67–3.970.282
Stroke0.730.06–8.160.794
Intraoperative characteristics
Duration of CPB1.011.0–1.010.044
Aortic cross-clamp time1.011.0–1.010.222
Duration of general anesthesia in surgery1.01.0–1.010.031
Postoperative characteristics
Systolic blood pressure0.990.97–1.010.181
Diastolic blood pressure0.970.94–1.00.026
Mean arterial blood pressure0.970.94–0.990.009
Duration of mechanical ventilation1.0431.02-1.066< 0.001
Duration of sedation in ICU1.01.0–1.00.004
Duration of sedation during and post surgery1.01.0–1.00.003
Fluid balance 24 h post surgery1.01.0–1.00.007
WBC1.111.02–1.210.014
Vasopressors0.350.18–0.670.001
Inotropes0.490.25–0.980.042
Table 3 Receiver operating characteristics curve analysis for major predictors of acute kidney injury development
Test result variable(s)Area under curveSEP value95%CI
Lower bound
Upper bound
CKD0.6020.0500.0360.5040.699
EuroScore II percentage (%)0.6920.0450.0000.6040.781
Duration of ECC (min)0.6180.0440.0150.5320.704
Duration of GA (min)0.6070.0470.0280.5150.699
Duration of ICU sedation (min)0.6250.0510.0100.5260.724
White blood cell (k/uL)0.6430.0460.0030.5540.733
Vasopressors0.6100.0490.0240.5140.706
Inotropes0.5620.0470.2040.4690.654
Fluid balance 1st day after cardiac surgery (mL)0.6340.0500.0060.5370.731
Table 4 Outcome characteristics of all patients and according acute kidney injury status
Outcome
AKI
No AKI
P value
Reintubation (n)6 (10.9)2 (1.3)0.005
Dialysis (n)4 (7)00.005
Duration of mechanical ventilation (min)1113 (777–2195)714 (511–1020)0.0001
Delirium (n)20 (36.4)36 (23.8)0.001
ICU acquired weakness (n)9 (16.4)8 (5.3)0.015
ICU length of stay (hours)70 (28–129)26 (21–51)0.0001
Mortality (n)2 (3.6)1 (0.7)0.046