Antipyrine elimination test as a guideline for selecting patients for transhepatic biliary drainage.

Antipyrine elimination halflife (AP t1/2) was studied in 18 patients with obstructive jaundice along with routine liver function tests 24-48 h before the expected time of percutaneous transhepatic biliary drainage (PTBD). To see if it is possible to predict the outcome of PTBD, various predrainage parameters were correlated with the postdrainage bilirubin clearance after 1 week of drainage. Predrainage AP t1/2 correlated best with bilirubin clearance (r = 0.775, P less than 0.01) compared with predrainage serum bilirubin, alkaline phosphatase and serum proteins/albumin. Eight patients had AP t1/2 less than 15 h, while 10 had AP t1/2 greater than 15 h. Patients with AP t1/2 less than 15 h had significantly faster recovery after PTBD than patients with AP t1/2 greater than 15 h. If PTBD can be restricted to those with AP t1/2 less than 15 h, the advantages of preliminary PTBD can be achieved with minimum complications. Thus, estimation of AP t1/2 may aid in the selection of patients with obstructive jaundice who are likely to benefit by preliminary biliary decompression.