Acute renal failure may develop after surgery and has a relatively high mortality rate. Cioffi et al developed a prognostic index for patients developing postoperative acute renal failure. The study was performed at the University of Vermont.
Parameters for prognostic index:
(1) age of the patient
(2) number of units of RBCs transfused
(3) type of surgery (cardiac and/or vascular surgery)
(4) heart failure
(5) preoperative hypotension
(6) gender
(7) time between onset of renal failure and starting of hemodialysis
Parameter |
Finding |
Points |
---|---|---|
age of the patient in years |
|
(age) |
number of RBC units transfused |
< 5 |
1 |
|
5 – 10 |
2 |
|
11 – 20 |
3 |
|
> 20 |
4 |
cardiac surgery |
no |
0 |
|
yes |
1 |
cardiac failure |
no |
0 |
|
yes |
1 |
gender |
female |
0 |
|
male |
1 |
vascular surgery other than abdominal aortic aneurysm |
no |
0 |
|
yes |
1 |
interval in days from onset of acute renal failure to hemodialysis |
|
(days) |
preoperative hypotension |
no |
0 |
|
yes |
1 |
where:
• For blood transfused, I've assumed that 0 units transfused gets 1 point.
linear discriminant function =
= (0.034 * (points for age)) - (0.472 * (points for number units transfused)) + (1.43 * (points for cardiac surgery)) - (1.21 * (points for cardiac failure)) + (1.44 * (points for gender)) + (1.09 * (points for vascular surgery)) - (0.050 * (points for interval in days before dialysis)) - (0.75 * (points for preoperative hypotension)) + 3.19
Interpretation:
• minimum score in study population: –2.04
• maximum score in study population: +3.95
• A score > 0.669 was usually associated with survival, while a negative score was usually associated with death.
Score |
Risk |
---|---|
< -0.423 |
high risk (no survivors) |
-0.423 to 1.76 |
intermediate risk |
> 1.76 |
low risk |
from page 209
Limitations:
• The index was developed in 1984 and survival has probably improved due to newer treatment modalities.
Purpose: To determine the chance of survival for a patient developing acute renal failure postoperatively.
Specialty: Nephrology, Clinical Laboratory
Objective: severity, prognosis, stage
ICD-10: N17,