Risk factors of ineffective drainage in uncovered self-expandable metal stenting for unresectable malignant hilar biliary strictures.
Aim
In this study, we assessed the factors contributing to ineffective drainage in the initial transpapillary uncovered self-expandable metal stent (USEMS) placements in patients with unresectable malignant hilar biliary strictures (UMHBSs) (Bismuth type II or higher).


Methods
This was a retrospective, single-center study. A total of 97 patients with UMHBSs who underwent technically successful initial USEMS placements using endoscopic retrograde cholangiopancreatography (ERCP) were classified into the effective drainage group (n = 73) or the ineffective drainage group (n = 24). We then compared group characteristics, clinical outcomes, and drained liver volumes. Drained liver volume was measured by using computed tomography volumetry. The definition of effective biliary drainage was a 50% decrease in the serum total bilirubin level or normalization of the level within 14 days of stent placement.


Results
Univariate analysis showed that ineffective drainage was associated with the pre-ERCP serum total bilirubin level (P = 0.0075), pre-ERCP serum albumin level (P = 0.042), comorbid liver cirrhosis (P = 0.010), drained liver volume (P = 0.0010), and single stenting (P = 0.022). Multivariate analysis identified comorbid liver cirrhosis (adjusted odds ratio [OR], 5.79; 95% confidence interval [CI], 1.30-25.85; P = 0.022) and drained liver volume < 50% (adjusted OR, 5.50; 95% CI, 1.50-20.25; P = 0.010) as independent risk factors of ineffective drainage.


Conclusion
Comorbid liver cirrhosis and a drained liver volume < 50% contributed significantly to ineffective drainage in the initial transpapillary USEMS placements for UMHBSs.
['Takahashi|Koji|K|', 'Tsuyuguchi|Toshio|T|', 'Saiga|Atsushi|A|', 'Horikoshi|Takuro|T|', 'Ooka|Yoshihiko|Y|', 'Sugiyama|Harutoshi|H|', 'Nakamura|Masato|M|', 'Kumagai|Junichiro|J|', 'Yamato|Mutsumi|M|', 'Iino|Yotaro|Y|', 'Shingyoji|Ayako|A|', 'Ohyama|Hiroshi|H|', 'Yasui|Shin|S|', 'Mikata|Rintaro|R|', 'Sakai|Yuji|Y|', 'Kato|Naoya|N|']
risk factor drainage stent endoscopic retrograde cholangiopancreatography