Laparoscopic Roux-en-Y gastric bypass using the porcine model.

BACKGROUND: The laparoscopic Roux-en-Y gastric bypass (LRYGBP) may be performed using a variety of methods. The purpose of this study was to learn how to perform the Roux-en-Y gastric bypass operation laparoscopically, using a porcine model. MATERIALS AND METHODS: 11 domestic pigs (mean weight 47 kg) underwent LRYGBP. In 8 animals, a completely laparoscopic approach was attempted, while in 3 animals a hand-assist device was used. Techniques for anvil placement, pouch calibration, and limb-length measurement were evaluated. Animals were sacrificed at the end of the procedure, and operative results were recorded. RESULTS: The hand-assist device restored tactile feedback but obscured visualization. The gastrojejunostomy leak rate was 64%, and the jejunojejunostomy leak rate was 73%. Anvil placement using transgastric and transoral methods was feasible. Calibrating the pouch with a Baker's tube was more accurate than using anatomical landmarks. Measuring limb-lengths using Babcock clamps was reliable with practice. CONCLUSION: The frailty of the porcine small intestine may limit one's ability to achieve intact anastomoses. Despite the anatomic limitations, the porcine model was well-suited for skill development and evaluation of techniques for performing the LRYGBP operation.

Evaluating surgical competency with the American Board of Surgery In-Training Examination, skill testing, and intraoperative assessment.

BACKGROUND: Evaluation of surgical competency should include assessment of knowledge, technical skill, and judgment. The purpose of this study was to determine the relationship between the American Board of Surgery In-Training Examination (ABSITE), skill testing, and intraoperative assessment. METHODS: Postgraduate year 2 (PGY-2) and postgraduate year 3 (PGY-3) surgery residents (n = 33) were tested by means of (1) the ABSITE, (2) skill testing on a laparoscopic video-trainer, and (3) intra-operative global assessments during laparoscopic cholecystectomy. The Pearson correlation was used to determine the correlation between the ABSITE, skill testing, and intraoperative assessments. For the comparison of PGY-2 and PGY-3 resident performance, Wilcoxon rank sum tests were used. RESULTS: The ABSITE scores did not correlate with skill testing or intraoperative assessments (not significant). Skill testing correlated with the intraoperative composite score and with 4 of 8 operative performance criteria (P<.05). The ABSITE scores and skill testing were not different for PGY-2 and PGY-3 residents (not significant). Intraoperative assessments were better in 5 of 8 criteria and the composite score for PGY-3 versus PGY-2 residents (P<.05), which demonstrated construct validity. CONCLUSIONS: The ABSITE measures knowledge but does not correlate with technical skill or operative performance. Residency programs should use multiple assessment instruments to evaluate competency. There may be a role for both skill testing and intraoperative assessment in the evaluation of surgical competency.

Laparoscopic training on bench models: better and more cost effective than operating room experience?

BACKGROUND: Developing technical skill is essential to surgical training, but using the operating room for basic skill acquisition may be inefficient and expensive, especially for laparoscopic operations. This study determines if laparoscopic skills training using simulated tasks on a video-trainer improves the operative performance of surgery residents. STUDY DESIGN: Second- and third-year residents (n= 27) were prospectively randomized to receive formal laparoscopic skills training or to a control group. At baseline, residents had a validated global assessment of their ability to perform a laparoscopic cholecystectomy based on direct observation by three evaluators who were blinded to the residents' randomization status. Residents were also tested on five standardized video-trainer tasks. The training group practiced the video-trainer tasks as a group for 30 minutes daily for 10 days. The control group received no formal training. All residents repeated the video-trainer test and underwent a second global assessment by the same three blinded evaluators at the end of the 1-month rotation. Within-person improvement was determined; improvement was adjusted for differences in baseline performance. RESULTS: Five residents were unable to participate because of scheduling problems; 9 residents in the training group and 13 residents in the control group completed the study. Baseline laparoscopic experience, video-trainer scores, and global assessments were not significantly different between the two groups. The training group on average practiced the video-trainer tasks 138 times (range 94 to 171 times); the control group did not practice any task. The trained group achieved significantly greater adjusted improvement in video-trainer scores (five of five tasks) and global assessments (four of eight criteria) over the course of the four-week curriculum, compared with controls. CONCLUSIONS: Intense training improves video-eye-hand skills and translates into improved operative performance for junior surgery residents. Surgical curricula should contain laparoscopic skills training.

Improving operative performance using a laparoscopic hernia simulator.

BACKGROUND: Traditionally, the acquisition of surgical skill has occurred entirely in the operating room. To meet the expanding challenges of cost containment and patient safety, novel methods of surgical training utilizing ex-vivo workstations are being developed. The purpose of our study was to evaluate the impact of a laparoscopic training curriculum on surgical residents' operative performance. METHODS: Twenty-one surgery residents completed baseline laparoscopic total extraperitoneal (TEP) hernia repairs. Operative performance was evaluated using a validated global assessment tool. Each resident was then randomized to a control group or a trained group. A CD ROM, video, and simulator were used for training. At the end of the study, each resident's operative performance was again evaluated. RESULTS: Improvement was significantly greater in the trained group in five of the eight individual global assessment areas as well as the composite score (P <0.05). Questionnaire data suggested that training resulted in improved understanding of the TEP hernia repair (P = 0.01) and an increased willingness to offer the operation to patients with nonrecurrent unilateral hernias (P = 0.02). CONCLUSIONS: A multimodality laparoscopic TEP hernia curriculum improves residents' knowledge of the TEP hernia repair and comfort in performing the procedure, and may also improve actual operative performance.

Laparoscopic skills training.

BACKGROUND: The purpose of this study was to quantify the learning curve of a previously validated laparoscopic skills curriculum. METHODS: Second-year medical students (MS2, n = 11) and second (PGY2, n = 11) and third (PGY3, n = 6) year surgery residents were enrolled into a curriculum using five video-trainer tasks. All subjects underwent baseline testing, training (30 minutes per day for 10 days), and final testing. Scores were based on completion time. The relationship between task completion time and the number of practice repetitions was examined. Improvement (the difference in baseline and final performance) amongst groups was compared by one-way analysis of variance using the baseline score as a covariate; P <0.05 indicated significance. RESULTS: Baseline scores were not significantly different. Final scores were significantly better for MS2s versus PGY3s. Adjusted-improvement was significantly larger for the MS2s compared with PGY2s and PGY3s, and for PGY2s compared with PGY3s. The mean number of repetitions corresponding to a predicted 90th percentile score was 32. CONCLUSION: Inexperienced subjects benefit the most from skills training. For maximal benefit, we recommend that each task be practiced for at least 30 to 35 repetitions.

The effect of hepatic inflow occlusion on laparoscopic radiofrequency ablation using simulated tumors.

BACKGROUND: The purpose of this study was to determine the effect of hepatic inflow occlusion (the Pringle maneuver) on laparoscopic radiofrequency (RF) ablation. METHODS: Using a previously validated agarose tissue-mimic model, 1-cm simulated hepatic tumors (three per animal) were laparoscopically ablated in five pigs with normal perfusion and then in five pigs with hepatic artery and portal vein occlusion. Energy was applied until tissue temperature reached 100 degrees C (warm-up) and thereafter for eight min. Specimens were examined immediately after treatment. RESULTS: Vascular occlusion was successful in all cases per color-flow Doppler ultrasound. Pringle time was 11.4 +/- 1.6 min. Warm-up time (2.7 +/- 1.4 vs 20.2 +/- 14.0 min) was significantly faster in the Pringle group. Ablation diameter (34.8 +/- 2.9 vs 24.7 +/- 3.1 mm), proportion of round/ovoid lesions (93% vs 20%), ablation symmetry (100% vs 40%), and margin distance (5.1 +/- 3.0 vs 1.1 +/- 1.2 mm) were significantly better for the Pringle group than the No Pringle group, respectively. CONCLUSION: Using a Pringle maneuver during laparoscopic RF ablation significantly enhances ablation geometry and results in larger margins.

Comparison of video trainer and virtual reality training systems on acquisition of laparoscopic skills.

Training on a video trainer or computer-based minimally invasive surgery trainer leads to improved benchtop laparoscopic skill. Recently, improved operative performance from practice on a video trainer was reported. The purpose of this study was three fold: (a) to compare psychomotor skill improvement after training on a virtual reality (VR) system with that after training on a video-trainer, (VT) (b) to evaluate whether skills learned on the one training system are transferable to the other, and (c) to evaluate whether VR or VT training improves operative performance. For the study, 50 junior surgery residents completed baseline skill testing on both the VR and VT systems. These subjects then were randomized to either a VR or VT structured training group. After practice, the subjects were tested again on their VR and VT skills. To assess the effect of practice on operative performance, all second-year residents (n = 19) were evaluated on their operative performance during a laparoscopic cholecystectomy before and after skill training. Data are expressed as percentage of improvement in mean score/time. Analysis was performed by Student's paired t-test. The VR training group showed improvement of 54% on the VR posttest, as compared with 55% improvement by the VT group. The VR training group improved more on the VT posttest tasks (36%) than the VT training group improved on the VR posttest tasks (17%) (p <0.05). Operative performance improved only in the VR training group (p <0.05). Psychomotor skills improve after training on both VR and VT, and skills may be transferable. Furthermore, training on a minimally invasive surgery trainer, virtual reality system may improve operative performance during laparoscopic cholecystectomy.

Surgeon workload and motion efficiency with robot and human laparoscopic camera control.

BACKGROUND: Surgeons are now being assisted by robotic systems in a wide range of laparoscopic procedures. Some reports have suggested that robot-assisted camera control (RACC) may be superior to a human driver in terms of quality of view and directional precision, as well as long-term cost savings. Therefore, we setout to investigate the impact of RACC of surgeon motion efficiency. METHODS: Twenty pigs were randomized to undergo a standardized laparoscopic Nissen fundoplication with either a human or RACC system, the AESOP 2000. All procedures were performed by the same surgical fellow. Time was recorded for dissection and suture phases. Inertial motion sensors were used to monitor both the surgeon's hands and the camera. Digitized data were analyzed to produce summary measures related to overall motion. RESULTS: The operative times were slightly longer with RACC (mean 80.2 +/- 20.6 vs 73.1 +/- 15.4 min, not significant). With regard to operative times and surgeon motion measures, the only statistically significant differences were for setup and breakdown times, which contributed <15% to the total time for the procedure. CONCLUSION: In terms of impact on surgeon motion efficiency and operative time under normal surgical conditions, RACC is essentially the same as an expert human driver. However, careful planning and structuring of the surgical suite may yield some small gains in operative time.

Measuring operative performance after laparoscopic skills training: edited videotape versus direct observation.

BACKGROUND AND PURPOSE: Global assessment by direct observation has been validated for evaluating operative performance of surgery residents after formal skills training but is time-consuming. The purpose of this study was to compare global assessment performed from edited videotape with scores from direct observation. MATERIALS AND METHODS: Junior surgery residents (N = 22) were randomized to 2 weeks of formal videotrainer skills training or a control group. Laparoscopic cholecystectomy was performed at the beginning and end of the rotation, and global assessment scores were compared for the training and control groups. Laparoscopic videotapes were edited: initial (2 minutes), cystic duct/artery (6 minutes), and fossa dissection (2 minutes). Two independent raters performed both direct observation and videotape assessments, and scores were compared for each rater and for interrater reliability using a Spearman correlation. RESULTS: Correlation coefficients for videotape versus direct observation for five global assessment criteria were <0.33 for both raters (NS for all values). The correlation coefficient for interrater reliability for the overall score was 0.57 (P = 0.01) for direct observation v 0.28 (NS) for videotape. The trained group had significantly better overall performance than the control group according to the assessment by direct observation (P = 0.02) but not by videotape assessment (NS). CONCLUSIONS: Direct observation demonstrated improved overall performance of junior residents after formal skills training on a videotrainer. Global assessment from an edited 10-minute videotape did not correlate with direct observation and had poor interrater reliability. Efficient and valid methods of evaluating operative performance await development.