Page 20 - ANZCP Gazette May 2023

Table 1. Preoperative and intraoperative risk factors for 30-day mortality in the creation and validation datasets.
Preoperative
Creation dataset Validation dataset p
n=15073
n=15072
Age group
<70 9038 (60%) 8994 (60%) 0.27
70-79 4509 (30%) 4467 (30%)
80+ 1526 (10%) 1611 (11%)
Female 3953 (26%) 4057 (27%) 0.17
Hypercholesterolaemia 9066 (60%) 9259 (61%) 0.022
Preoperative dialysis 248 (2%) 292 (2%) 0.056
Respiratory disease 1907 (13%) 1869 (12%) 0.51
Critical preoperative state
Peripheral vascular disease 1030 (7%) 969 (6%) 0.16
585 (4%)
580 (4%)
0.88
Cerebrovascular disease 1183 (8%) 1192 (8%) 0.85
Previous cardiac surgery 1269 (8%) 1244 (8%) 0.6
Cardiogenic shock 190 (1%) 189 (1%) 0.96
Ejection fraction estimate
>60% 12434 (82%) 12415 (82%) 0.8
46-60% 42 (<1%) 34 (<1%)
30-45% 1891 (13%) 1904 (13%)
<30% 706 (5%) 719 (5%)
Urgency of procedure
Elective 10574 (70%) 10703 (71%) 0.44
Urgent 4005 (27%) 3891 (26%)
Emergency 484 (3%) 469 (3%)
Salvage 10 (<1%) 9 (<1%)
NYHA class
1 10970 (73%) 10970 (73%) 0.16
2 153 (1%) 144 (1%)
3 3066 (20%) 3153 (21%)
4 884 (6%) 805 (5%)
Procedure type
CABG 7484 (50%) 7449 (49%) 0.62
Valve repair/replacement 3059 (20%) 3150 (21%)
Valve + CABG 1623 (11%) 1602 (11%)
Other 2907 (19%) 2871 (19%)
Body mass index >25 kg/m2 10605 (70%) 10764 (71%) 0.043
Intraoperative
CPB time, minutes 91 (70, 119) 91 (70, 119)
Aortic cross clamp time, minutes 64 (47, 88) 64 (46, 89)
0.66 0.83
0.54
0.52 0.54 0.7 0.54 0.74 0.27 0.43 0.33 0.44 0.4 0.35 0.088 0.058 0.29 0.98
Red blood cell transfusion
0 13086 (87%) 13113 (87%)
1 612 (4%) 644 (4%)
2 778 (5%) 743 (5%)
3 or greater 597 (4%) 572 (4%)
CPB minimum oxygen delivery, ml/min/m2 282 (244, 321) 281 (244, 321)
CPB cardiac index <1.8 l/min/m2, min 4.5 (2.3, 9.7) 4.5 (2.3, 9.7)
CPB cardiac index <1.6 l/min/m2, min 3.0 (1.7, 6.0) 3.0 (1.7, 6.0)
CPB cardiac index average, l/min/m2 4.5 (2.3, 9.7) 4.5 (2.3, 9.7)
CPB mean arterial press <50 mmHg, min 7.7 (3.5, 15.0) 8.0 (3.5, 15.0)
CPB mean arterial press <40mmHg, minu
CPB mean arterial press average, mmHg 63 (59, 68) 63 (59, 68)
1.5 (0.5, 3.5)
1.5 (0.5, 3.5)
CPB minimum blood glucose, mmol/l 6 (6, 8) 6 (6, 7)
CPB maximum blood glucose, mmol/l 8 (7, 10) 8 (7, 10)
CPB minimum hemoglobin, g/dl 91 (78, 103) 91 (79, 103)
CPB minimum nasopharyngeal temp, oC 34 (32, 34) 34 (32, 34)
CPB arterial blood temp >36.5oC, min 1 (0, 14) 1 (0, 14)
CPB minimum arterial pCO2, mmHg 37 (35, 39) 37 (35, 39)
CPB maximum arterial pCO2, mmHg 41 (39, 44) 41 (39, 44)
CPB venous saturation <60%, minutes 0 (0, 1) 0 (0, 1)
Data presented as n (%) or median (IQR). NYHA: New York Heart Association; CPB: cardiopulmonary bypass.
17 MAY 2023 | www.anzcp.org