title: Impact of Preoperative ERCP on Laparoscopic Cholecystectomy: A Case-Controlled Study with Propensity Score Matching.
abstract: BACKGROUND
  Although inflammation induced by endoscopic retrograde cholangiopancreatography (ERCP) may affect laparoscopic cholecystectomy (LC), making the procedure more difficult, clinical impact of ERCP on LC is unclear. The aim of this study was to evaluate the effects of ERCP on LC and to determine appropriate time of LC after ERCP.
  
  
  METHODS
  Six hundred twenty-one patients who underwent LC for gallstone disease were enrolled. These patients were divided into two groups; patients with preoperative ERCP prior to LC (ERCP group) and patients who underwent LC without ERCP (non-ERCP group). Among these patients, patients who had shown acute cholecystitis or cholangitis were excluded. To control for different demographic factors in the two groups, propensity score case matching was used at a 1:1 ratio. Finally, 142 patients were matched with 71 patients of the ERCP group and 71 patients of the non-ERCP group. Intraoperative inflammation degree, technical difficulty, and postoperative outcome were analyzed.
  
  
  RESULTS
  In the ERCP group, the degree of inflammation was severe and operations were more difficult than those of the non-ERCP group. The operation time was longer, and rates of open conversion were higher in the ERCP group. On multivariate analysis, preoperative ERCP was significant factor for difficult operations. The difficulty of operation was not different according to the operation timing after ERCP.
  
  
  CONCLUSIONS
  Preoperative ERCP is a significant factor in difficult LC. Therefore, experienced surgeons should perform LC after preoperative ERCP. Since operation difficulty was similar according to the timing of cholecystectomy after ERCP, there is no reason to delay LC after ERCP.
authors.affiliation: Department of Surgery, Dongsan Medical Center, Keimyung University School of Medicine, 56 Dalseong-ro, Jung-gu, Daegu, 700-712, Republic of Korea, ahnks@dsmc.or.kr.
authors.forename: Keun Soo
authors.initials: KS
authors.lastname: Ahn
authors.forename: Yong Hoon
authors.initials: YH
authors.lastname: Kim
authors.forename: Koo Jeong
authors.initials: KJ
authors.lastname: Kang
authors.forename: Tae-Seok
authors.initials: TS
authors.lastname: Kim
authors.forename: Kwang Bum
authors.initials: KB
authors.lastname: Cho
authors.forename: Eun Soo
authors.initials: ES
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000009:adverse effects*; D002761:Cholangitis / Q000209:etiology; D017081:Cholecystectomy, Laparoscopic; D002764:Cholecystitis / Q000209:etiology; D061887:Conversion to Open Surgery; D005260:Female; D042882:Gallstones / Q000150:complications / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D011300:Preoperative Care / Q000009:adverse effects*; D057216:Propensity Score; D013997:Time Factors