Serum bilirubin after surgery for obstructive jaundice.

A method of analysis of bilirubin clearance is suggested, which allows the calculation of a decay constant (k) and half-life (t0.5). These parameters allow ready comparison of the bilirubin clearance between patient groups. The value of k could be predicted with reasonable accuracy by a regression equation employing as determinants a score for cholangitis, pre-operative serum ALT and bilirubin, and the patient's sex. Bilirubin clearance is known to correlate strongly with antipyrine clearance, and antipyrine clearance with prognosis after biliary drainage. A similar prognostic index may be derived from simple clinical and biochemical parameters which will predict the decay constant and half-life of endogenous bilirubin.