Yu et al reported a nomogram for predicting the risk of nosocomial infection following cardiac surgery for congenital heart disease. The authors are from Shanghai Children's Medical Center.
Patient selection: infant undergoing cardiac surgery for congenital heart disease
Parameters:
(1) age in months, from 1 to 11
(2) STS (Society of Thoracic Surgeons) risk grade
(3) percentile for body mass index
(4) cardiopulmonary bypass time in minutes, from 0 to 500
(5) aortic clamping time in minutes, from 0 to 240
(6) percent neutrophils
points for age =
= 60.94 - (5.54 * (age in months))
points for cardiopulmonary bypass time =
= 0.2 * (time)
points for aortic clamping time =
= 0.17833 * (time)
Parameter
|
Finding
|
Points
|
STS risk grade
|
1
|
0
|
|
2
|
5.5
|
|
3
|
10.8
|
|
4
|
16
|
|
5
|
21.4
|
percentile for BMI
|
< 5th percentile
|
10.7
|
|
5th to 95th percentile
|
5.5
|
|
> 95th percentile
|
0
|
percent neutrophils
|
low (below LLN)
|
0
|
|
normal
|
5.8
|
|
high (above ULN)
|
12.6
|
total score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score: 0
• maximum score: 242.9
value of X =
= (0.04206 * (score)) - 4.433
probability of nosocomial infection =
= 1 / (1 + EXP((-1) * X))
Performance:
• The area under the ROC curve is 0.82.