Bagshaw et al identified risk factors for mortality within 1 year for patients in the intensive care unit (ICU) who develop severe acute renal failure. These can help identify patients who may benefit from more aggressive monitoring and management. The authors are from the University of Calgary and the University of Alberta in Canada.
Patient selection: critically ill adult with severe acute renal failure
Risk factors for 1 year mortality:
(1) male gender (see Figure 1 and 2 page R703).
(2) age >= 65 years of age
(3) concurrent disease
|
Measure of Concurrent Disease |
Finding |
Odds Ratio |
|
Charlson co-morbidity index |
per point |
1.2 |
|
APACHE II score |
per 5 points |
1.24 |
|
septic shock |
present |
2.1 |
|
need for continuous renal replacement |
present |
6.0 |
|
liver disease |
present |
6.5 |
from Table 5, page R706
where:
• The maximum APACHE II score is 71.
• The maximum Charlson co-morbidity score may be in the order of 20.
• According to the text on page R704 gender was not needed in the model to predict mortality. Age was a factor on univariate analysis but was not included in the multivariate model shown in Table 5.
A problem is how to use this information. Below is one possible way, which is untested. The points for concurrent diseases are based on dividing the odds ratio by 2.
|
Parameter |
Finding |
Points |
|
Charlson comorbidity |
|
ROUND((index) * 1.2 / 2,0) |
|
APACHE II score |
|
ROUND((score) * 1.2 / (5 * 2),0) |
|
septic shock |
absent |
0 |
|
|
present |
1 |
|
need for continuous renal replacement therapy |
absent |
0 |
|
|
present |
3 |
|
liver disease |
absent |
0 |
|
|
present |
3 |
total score =
= SUM(points for all 5 parameters)
Interpretation:
• minimum score: 0
• maximum score: around 25
• The higher the score the greater the risk of 1 year mortality.
Specialty: Nephrology, Clinical Laboratory
