Wiseman et al developed a model for surgical site infection (SSI) in patients undergoing major vascular surgery. These can help to identify patients who may benefit from more aggressive management. The authors are from the University of Wisconsin.
Patient selection: major vascular surgery
Outcome: surgical site infection post-discharge and within 30 days
Parameters:
(1) age in years
(2) gender
(3) race
(4) ASA class
(5) weight status
(6) type of revascularization procedure
(7) operative time in hours
(8) diabetes mellitus
(9) smoking status
(10) hypertension
(11) critical limb ischemia
(12) dyspnea
(13) groin anastomsosis
(14) COPD
(15) coronary artery disease (CAD)
(16) neurological disease
(17) sepsis complications
(18) renal complication
(19) functional status
(20) length of stay in days
Parameter |
Finding |
Points |
age in years |
< 65 years |
0 |
|
>= 65 years |
-1 |
Gender |
male |
0 |
|
female |
4 |
Race |
Black |
-2 |
|
other |
0 |
ASA class |
I to III |
0 |
|
IV or V |
2 |
weight status |
not overweight |
0 |
|
overweight |
3 |
|
obese |
9 |
type of procedure |
lower extremity revascularization |
12 |
|
aortoiliac procedure |
9 |
|
other |
0 |
operative time |
< 4 hours |
0 |
|
4 to 6 hours |
3 |
|
> 6 hours |
5 |
diabetes mellitus |
no |
0 |
|
not insulin dependent |
2 |
|
insulin dependent |
3 |
smoking status |
not a smoker |
0 |
|
smoker |
2 |
hypertension |
absent |
0 |
|
present |
2 |
critical limb ischemia |
absent |
0 |
|
present |
2 |
dyspnea |
on moderate exertion |
2 |
|
on severe exertion |
0 |
groin anastomosis |
absent |
0 |
|
present |
2 |
COPD |
absent |
0 |
|
present |
1 |
coronary artery disease |
absent |
0 |
|
present |
1 |
neurological disease |
absent |
0 |
|
present |
1 |
sepsis complication |
absent |
0 |
|
present |
-4 |
renal complication |
absent |
0 |
|
present |
-6 |
functional status |
totally dependent |
-6 |
|
not totally dependent |
0 |
length of stay in days |
< 14 days |
0 |
|
>= 14 days |
-9 |
total score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score: -28
• maximum score: 48
• According to the paper the result range was -20 to 45 but this could be results seen in patients.
• The higher the score the greater the risk for surgical site infection after discharge.
Total Score |
Percent with SSI Post-Discharge |
<= -9 |
0% |
< 0 |
< 1% |
0 to 20 |
(0.01 * ((score)^2)) + (0.054 * (score)) + 0.98 |
> 20 |
(0.03507 * ((score)^2)) - (1.076 * (score)) + 13.74 |
Score |
Risk Group |
< 16 |
low risk |
16 to 20 |
low-to-moderate risk |
21 to 25 |
moderate-to-high risk |
> 25 |
high risk |
Performance:
• The bias-correct area under the ROC curve was 0.691.
Specialty: Infectious Diseases