title: Time-action analysis of instrument positioners in laparoscopic cholecystectomy.
abstract: BACKGROUND
  Instrument positioners can position and lock a laparoscopic instrument. This study uses time-action analysis to evaluate objectively whether IPs can substitute for a surgical assistant efficiently and safely.
  
  
  METHODS
  In four hospitals, 78 laparoscopic cholecystectomies were randomly assisted by a surgical assistant or an instrument positioner (AESOP and PASSIST) The efficiency and safety of laparoscopic cholecystectomies were analyzed with respect to time, number and type of actions, positioning accuracy, and peroperative complications. A questionnaire evaluated the difficulties for each operation and the comfort of instrument positioner use.
  
  
  RESULTS
  The PASSIST and AESOP were able to replace the surgical assistant during laparoscopic cholecystectomies without significantly changing either the efficiency or the safety of the operation. The questionnaire showed that the surgeons preferred to operate with an instrument positioner.
  
  
  CONCLUSIONS
  This study assessed objectively that instrument positioners can substitute for a surgical assistant efficiently and safely in elective laparoscopic cholecystectomies.
authors.affiliation: Faculty of Design, Engineering and Production, Delft University of Technology, Delft, The Netherlands.
authors.forename: K T
authors.initials: KT
authors.lastname: den Boer
authors.forename: M
authors.initials: M
authors.lastname: Bruijn
authors.forename: J E
authors.initials: JE
authors.lastname: Jaspers
authors.forename: L P S
authors.initials: LP
authors.lastname: Stassen
authors.forename: W F M
authors.initials: WF
authors.lastname: Erp
authors.forename: A
authors.initials: A
authors.lastname: Jansen
authors.forename: P M N Y H
authors.initials: PM
authors.lastname: Go
authors.forename: J
authors.initials: J
authors.lastname: Dankelman
authors.forename: D J
authors.initials: DJ
authors.lastname: Gouma
mesh_terms: D017081:Cholecystectomy, Laparoscopic / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D025321:Surgery, Computer-Assisted / Q000295:instrumentation* / Q000379:methods*; D011795:Surveys and Questionnaires; D013997:Time Factors