Lien and Chan developed an equation for predicting survival in a patient with acute renal failure requiring hemodialysis. This can help identify patients who may require more aggressive management. The authors are from Columbian Hospital in New Westminster, British Columbia.


Parameters identified on multivariate analysis:

(1) age of the patient in years

(2) CNS depression

(3) need for inotropic drug support to maintain the blood pressure (as a marker of significant persistent hypotension)




age of the patient in years



CNS depression

present after the 1st week



absent after the 1st week


inotropic drug support

required after the 1st week



not required after the 1st week



X =

= 3.2517 + (1.7243 * (points for CNS depression)) + (8.3925 * (points for inotropic drug support)) + (0.0876 * (age in years))


probability of survival =

= 1 / (1 + EXP(X))



• The usual expression would be 1 / (1 + EXP((-1) * X)). Thus, advanced age and the presence of the other 2 risk factors exert a negative influence on survival.

• Other adverse risk factors affecting survival were sepsis, heart failure, jaundice (liver failure), malnutrition, and respiratory failure (requirement for mechanical ventilation).



• The score was formulated over 15 years ago, and survival is likely to have improved in the interval.


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