title: Trans-umbilical endoscopic cholecystectomy with a water-jet hybrid-knife: a pilot animal study.
abstract: OBJECTIVE
  To investigate the feasibility and safety of Natural orifice trans-umbilical endoscopic cholecystectomy with a water-jet hybrid-knife in a non-survival porcine model.
  
  
  METHODS
  Pure natural orifice transluminal endoscopic surgery (NOTES) cholecystectomy was performed on three non-survival pigs, by transumbilical approach, using a water-jet hybrid-knife. Under general anesthesia, the following steps detailed the procedure: (1) incision of the umbilicus followed by the passage of a double-channel flexible endoscope through an overtube into the peritoneal cavity; (2) establishment of pneumoperitoneum; (3) abdominal exploration; (4) endoscopic cholecystectomy: dissection of the gallbladder performed using water jet equipment, ligation of the cystic artery and duct conducted using nylon loops; and (5) necropsy with macroscopic evaluation.
  
  
  RESULTS
  Transumbilical endoscopic cholecystectomy was successfully completed in the first and third pig, with minor bleedings. The dissection times were 137 and 42 min, respectively. The total operation times were 167 and 69 min, respectively. And the lengths of resected specimen were 6.5 and 6.1 cm, respectively. Instillation of the fluid into the gallbladder bed produced edematous, distended tissue making separation safe and easy. Reliable ligation using double nylon loops insured the safety of cutting between the loops. There were no intraoperative complications or hemodynamic instability. Uncontrolled introperative bleeding occurred in the second case, leading to the operation failure.
  
  
  CONCLUSIONS
  Pure NOTES trans-umbilical cholecystectomy with a water-jet hybrid-knife appears to be feasible and safe. Further investigation of this technique with long-term follow-up in animals is needed to confirm the preliminary observation.
authors.affiliation: Sheng-Jun Jiang, Gyanendra Swar, Hai-Xia Wang, Xiao-Jing Liu, Yong-Guang Wang, Department of Minimally Invasive Surgery, Beijing Chuiyangliu Hospital, Beijing 100022, China.
authors.forename: Sheng-Jun
authors.initials: SJ
authors.lastname: Jiang
authors.forename: Hong
authors.initials: H
authors.lastname: Shi
authors.forename: Gyanendra
authors.initials: G
authors.lastname: Swar
authors.forename: Hai-Xia
authors.initials: HX
authors.lastname: Wang
authors.forename: Xiao-Jing
authors.initials: XJ
authors.lastname: Liu
authors.forename: Yong-Guang
authors.initials: YG
authors.lastname: Wang
mesh_terms: D000818:Animals; D016063:Blood Loss, Surgical; D002763:Cholecystectomy / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods*; D003549:Cystic Duct / Q000601:surgery; D004210:Dissection; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D005704:Gallbladder / Q000601:surgery*; D008026:Ligation; D008297:Male; D023421:Models, Animal; D057605:Natural Orifice Endoscopic Surgery / Q000009:adverse effects / Q000295:instrumentation*; D011028:Pneumoperitoneum, Artificial; D013525:Surgical Instruments; D013552:Swine; D013997:Time Factors; D014472:Umbilicus / Q000601:surgery*
keywords: Cholecystectomy; Hybrid-knife; Natural orifice transluminal endoscopic surgery; Triangulation; Water-jet