The medical records of adult patients who have received a technically successful PTBD will be screened sytematically in terms of bilirubin and GGT values in the follow up of 4 weeks after the intervention. Bilirubin and GGT values have been routinely examinated every 1 to 3 days. PTBD comprises external plastic endoprosthesis, combined external and internal endoprosthesis and primary metal stent insertion. The respective three procedures are considered separately. As PTBD is a rare intervention which is used after failed or impossible endoscopic retrograde cholangiopancreaticography (ERCP) medical records will be screened from 2002 to 2022 (20 years). It is expected that for example a decrease of GGT after three days might indicate a successful procedure. This in turn might has an impact on the early demission of the patient. On the other side, the precise definition of successful PTBD by bilirubin or GGT value might help to make this procedure better comparable to other alternative biliary drainage procedures such as endoscopic ultrasound-guided biliary drainage.
The clinical success of percutaneous transhepatic biliary drainage procedures (PTBDs) is usually measured by the the decrease of the serum bilirubin value. However, the bilirubin value can be biased by other disease conditions. Furthermore, the time course of the decrease of the bilirubin value after technically successful PTBD is not well known. Serum gamma-glutamyl transferase (GGT), a liver enzyme which is typically elevated in cholestatic liver diseases, might be a good alternative to bilirubin as an indicator for the clinical success of PTBDs. The aim of this study is to analyse the bilirubin level and the GGT level in patients with technically successful PTBD.