Table 1.

Baseline demographics, operative characteristics, and AKI incidence, stratified by preoperative eGFR

Preoperative eGFR, ml/minaP
<30 (n = 21)30 to 60 (n = 101)60 to 90 (n = 142)90 to 120 (n = 109)>120 (n = 53)
Baseline patient variables
    Women, n (%)7 (33)45 (45)48 (34)31 (28)13 (25)0.07
    Age, yr, mean (SD)73.4 (13)73.6 (10)65.6 (13)55.5 (14)49.2 (12)0.01
    BMI, kg/m2, median (interquartile range)25.2 (21 to 30)25.3 (22 to 27)26.5 (24 to 29)26.6 (24 to 31)30 (27 to 34)0.01
    Preoperative creatinine, mg/dl, mean (SD)2.1 (1.21)1.3 (0.36)1.0 (0.26)0.9 (0.19)0.9 (0.18)0.001
    Parsonnet score, mean (SD)12.7 (7.6)11.9 (9.1)9.1 (7.0)6.9 (6.2)7.7 (6.3)0.001
    eGFR, mean (SD)15.3 (11)47.3 (8.5)73.7 (8.1)102.5 (8.2)140 (24.7)N/A
Operative characteristics
    OPCABG, n (%)2 (10)15 (15)18(13)13 (12)5 (9)0.88
    CABG, n (%)3 (14)22 (22)26 (18)18 (17)3 (6)0.24
    Open chamber +/− CABG, n (%)13 (62)56 (55)90 (64)73 (67)40 (75)0.15
    Transplant/VAD, n (%)3 (14)8 (8)8 (6)3 (3)1 (2)0.37
    Other, n (%)0 (0)0 (0)0 (0)2 (2)4 (8)0.02
    Reoperation, n (%)2 (10)16 (16)21 (15)10 (9)9 (17)0.52
    CPB time, min, mean (SD)120 (52)124 (49)128 (50)123 (45)113 (43)0.65
    AXC time, min, mean (SD)90 (28)90 (38)87 (33)83 (35)78 (31)0.49
    Aprotinin, n (%)10 (48)57 (56)76 (54)41 (38)24 (45)0.05
Postoperative characteristics
    AKI, n (%)b9 (41)20 (20)35 (25)13 (12)8 (15)0.01
  • OPCABG, off-pump coronary artery bypass graft surgery; CABG, coronary artery bypass graft surgery, on-pump; VAD, ventricular assist device; AXC, aortic cross-clamp duration.

  • a eGFR was calculated by Cockcroft-Gault equation.

  • b AKI was defined by serum creatinine increase >50% or >0.3 mg/dl above baseline within 48 hours of surgery.