title: Robot assistant for laparoscopic cholecystectomy.
abstract: BACKGROUND
  The role of a robotic assistant in laparoscopic cholecystectomy is controversial. While some trials have shown distinct advantages of robotic assistant over a human assistant, others have not, and it is unclear which robotic assistant is best.
  
  
  OBJECTIVE
  The aims of this review are to compare the safety of robot assistant versus human assistant in laparoscopic cholecystectomy and to assess whether the robot can substitute for the human assistant.
  
  
  METHODS
  We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until May 2008 for identifying the randomised trials using The Cochrane Hepato-Biliary Group search strategy.
  
  
  METHODS
  Only randomised clinical trials (irrespective of language, blinding, or publication status) comparing robot assistants versus human assistants in laparoscopic cholecystectomy were considered for the review. Randomised clinical trials comparing different types of robot assistants were also considered for the review.
  
  
  METHODS
  Two authors independently identified the trials for exclusion and independently extracted the data. We calculated the risk ratio, mean difference, or standardised mean difference with 95% confidence intervals using the fixed-effect and the random-effects models based on available case-analysis using RevMan 5.
  
  
  RESULTS
  We included five trials (all of high risk of bias) with 453 patients randomised: 159 to the robot-assistant group and 165 to the human assistant group (one trial report of 129 patients was a conference abstract, not reporting on the number of patients in each group). There was no statistically significant difference between the two groups for morbidity, conversion to open cholecystectomy, total operating time, or hospital stay when fixed-effect or random-effects model were used. The instrument set-up time was significantly lower in the human assistant group. In one trial, about one sixth of the laparoscopic cholecystectomies in which robot assistant was used, required temporary use of a human assistant. It appears that there was little or no requirement for human assistants in the other three published trials. In two of the three trials, which reported surgeons' preference, the surgeons preferred a robot assistant to a human assistant. There was no statistically significant difference in the accuracy when the random-effects model was used. There was no difference in the errors.
  
  
  CONCLUSIONS
  Although robot-assisted laparoscopic cholecystectomy appears safe, there seems to be no significant advantages over human-assisted laparoscopic cholecystectomy. We were unable to identify trials comparing one type of robot assistant versus another. Further randomised trials with low bias-risk and random errors are needed.
authors.affiliation: University Department of Surgery, Royal Free Hospital and University College School of Medicine, 9th Floor, Royal Free Hospital, Pond Street, London, UK, NW3 2QG. kurinchi2k@hotmail.com
authors.forename: Kurinchi Selvan
authors.initials: KS
authors.lastname: Gurusamy
authors.forename: Kumarakrishnan
authors.initials: K
authors.lastname: Samraj
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Fusai
authors.forename: Brian R
authors.initials: BR
authors.lastname: Davidson
mesh_terms: D017081:Cholecystectomy, Laparoscopic / Q000379:methods*; D006801:Humans; D012371:Robotics / Q000379:methods*; D012449:Safety