Actual vs predicted risk mortality Table 11 and Figure 14 present the distribution and numerical comparison of actual mortality against the mortality risk scores at 30-days post-operation. Actual mortality is calculated by the number of mortalities observed in each procedure type divided by the number of cases in each procedure type. The actual mortality rate for cardiac cases in 2021 was within acceptable parameters for the MultiRisk and EuroSCORE II scoring systems. The large difference between the predicted and observed mortalities in the aortic (± CABG/valve) category is due to the two risk scoring systems used, which underestimate risk in aortic dissection patients (that make up 55.6% of this group). To address this issue, in the future, a risk score better calibrated to this specific cohort will be used. Similarly, the other (± CABG/valve) group includes a wide range of procedures, some of which were high risk and infrequent (e.g. pulmonary embolectomy), so the risk scoring systems are also not well calibrated for them. The most important comparator in Figure 14 is the isolated CABG group, as this procedure is performed in the highest numbers and the risk scores are considered the most accurate. That is why this is often used to benchmark performance.
Additional information on the MultiRisk and EuroSCORE II risk evaluation methods can be found in the Appendix.
Procedure type
Actual mortality %
EuroSCORE II % median (IQR)
MultiRisk % median (IQR)
All
4
1.9 (1, 3.6)
1.6 (0.8, 2.9)
Isolated CABG
1.2
1.2 (0.9, 2)
0.9 (0.6, 1.6)
Isolated valve
3.5
2.3 (1.4, 3.7)
2.5 (1.7, 4.1)
Aortic (± CABG/valve)
8.9
3.7 (2.2, 8.3)
2.1 (1.1, 4.1)
Figure 14. Comparison of the actual mortality rate against various mortality risk scores
Other (± CABG/valve)
9.8
3.4 (1.7, 6.4)
3.2 (1.9, 4.9)
Valve + CABG
3.6
3.2 (2.5, 5.3)
2.5 (1.9, 4.3)
Table 11. Numerical summary of the comparison of actual mortality against various mortality risk scores. Values for each mortality risk score are displayed as medians and interquartile ranges (IQR). Actual mortality is calculated by the number of mortalities observed in each procedure type divided by number of cases in each procedure type.
24
25
Cardiac Surgery Annual Report 2021
Cardiac Surgery Annual Report 2021
Made with FlippingBook - professional solution for displaying marketing and sales documents online