The risk of perioperative mortality associated with elective repair of an abdominal aortic aneurysm can be predicted using a score developed by Steyerberg et al. This can help inform the patient of the risks associated with the surgery.
NOTE: I don't think these rates apply to endoluminal repair.
Parameters:
(1) surgeon or center-specific average operative mortality
(2) age of the patient in years
(3) gender of the patient
(4) cardiac comorbidity, based on myocardial infarction, congestive heart failure and ECG evidence of ischemia (ST segment depression > 2 mm)
(5) renal comorbidity
(6) pulmonary comorbidity
Parameter |
Finding |
Points |
center/surgeon-specific average operative mortality |
3% |
-5 |
|
4% |
-2 |
|
5% |
0 |
|
6% |
+2 |
|
8% |
+5 |
|
12% |
+10 |
age in years |
60 |
-4 |
|
70 |
0 |
|
80 |
+4 |
gender |
male |
0 |
|
female |
+4 |
history of myocardial infarction |
present |
+3 |
|
absent |
0 |
congestive heart failure |
present |
+8 |
|
absent |
0 |
ECG evidence of ischemia |
present |
+8 |
|
absent |
0 |
renal comorbidity |
creatinine <= 1.8 mg/dL |
0 |
|
creatinine > 1.8 mg/dL |
+12 |
pulmonary comorbidity |
COPD and/or dyspnea present |
+7 |
|
both absent |
0 |
where:
• Points for age is assigned with 1 point change for every 2.5 years (page 2002). I am not sure if this extends below 60 years or above 80 years. In the implementation I left them fixed at –4 and +4 respectively.
• If the surgeon's/center's mortality from 5% to 12% is placed in JMP, the following equation fits the data:
points for surgeon's/center's mortality rate =
= (-0.0618 * ((surgeon's percent as a whole number)^2)) + (2.4672 * (surgeon's percent as a whole number)) – 10.7129
total score =
= SUM(points for all 6 parameters)
Interpretation:
• minimum score: -9
• maximum score: 56
• The higher the score the greater the risk of mortality.
Total Score |
Mortality |
-5 |
1% |
0 |
2% |
5 |
3% |
10 |
5% |
15 |
8% |
20 |
12% |
25 |
19% |
30 |
28% |
35 |
39% |
40 |
51% |
An equation approximating this data derived in JMP:
probability of mortality =
= (0.0003497 * ((score)^3)) + (0.013613 * ((score)^2)) + (0.140909 * (score)) + 1.697436
Purpose: To predict the perioperative mortality for a patient have elective surgical repair of an abdominal aortic aneurysm using the method of Steyerberg et al.
Specialty: Cardiology
Objective: risk factors, severity, prognosis, stage, complications, complication detection, comorbid conditions
ICD-10: I71,