Gerald M. Fried

The effect of practice on performance in a laparoscopic simulator

AbstractBackground: Laparoscopic skill was measured objectively in a simulator. Seven tasks were scored in terms of precision and speed. These tasks included transferring, cutting, clip+ divide, placement of a ligating loop, mesh placement+ fixation, and suturing with intracorporeal and extracorporeal knot.n Methods: After baseline evaluation, 12 surgical residents were randomized to either five weekly practice sessions (Group A) or no practice (Group B). Each group was then retested. Performance scores were compared for baseline versus final test, and improvement (baseline to final) for Group A versus Group B. Group A residents had a total of seven repetitions of each task (baseline, five practices, final). Linear regression analysis was used to test for the correlation between score and repetition number.n Results: Group A showed significant improvement in their scores (baseline to final) for each task and for the total score (sum of all tasks) (p < 0.05). Group B showed significant improvement in four of seven tasks and for the total score. The magnitude of improvement of Group A versus Group B residents was significantly greater for four of seven tasks (peg transfer, placement of ligating loop, and both suturing skills) and for the total score. The final total score for Group A was 219 ± 14% of baseline (p < 0.0001), whereas Group B was only 162 ± 35% of baseline (p= 0.07) and not statistically significant. For Group A residents, there was a highly significant correlation between trial number and performance score (p < 0.05) for each individual task and for the total score.n Conclusions: Laparoscopic skill can be measured objectively in a simulator, and performance improves progressively with practice. These skills can be incorporated into the training and evaluation of residents in laparoscopic surgery.

Comparison of laparoscopic performance in vivo with performance measured in a laparoscopic simulator

AbstractBackground: Laparoscopic skill was measured objectively through a series of seven tasks in an inanimate laparoscopic simulator. Seven analogous skills were tested in an in vivo porcine model. These skills included transferring, cutting, clipping, placement of a ligating loop, mesh placement, and suturing with an intracorporeal and extracorporeal knot. Scoring of each task rewarded precision and speed.n Methods: Twelve PGY3 residents were given a baseline evaluation in the simulator and in the animal model. They were then randomized to either five practice sessions in the simulator (group A) or no practice (group B). Each group was retested in the simulator and in the animal (final test). Scores in vivo were compared by t-test for baseline versus final evaluation for each group. Linear regression analysis was used to correlate in vivo and in vitro scores for each task and for the total score (sum of all scores).n Results: Group A showed significant improvement in performance in vivo for cutting, clipping, mesh placement, and suturing with an intracorporeal and extracorporeal knot, as well as in the total score (p < 0.05). Group B showed significant improvement in suturing with an intracorporeal and extracorporeal knot, and in the total score. The magnitude of improvement from baseline to final evaluation was significantly greater for group A (p < 0.05). There was significant correlation between in vitro and in vivo total scores and the score for each task (p < 0.05) except for placement of the ligating loop and mesh.n Conclusions: Performance in an in vitro laparoscopic simulator correlated significantly with performance in an in vivo animal model. Practice in the simulator resulted in improved performance in vivo.

Fundamentals of endoscopic surgery: creation and validation of the hands-on test

AbstractBackgroundThe Fundamentals of Endoscopic Surgery™ (FES) program consists of online materials and didactic and skills-based tests. All components were designed to measure the skills and knowledge required to perform safe flexible endoscopy. The purpose of this multicenter study was to evaluate the reliability and validity of the hands-on component of the FES examination, and to establish the pass score.nMethodsExpert endoscopists identified the critical skill set required for flexible endoscopy. They were then modeled in a virtual reality simulator (GI Mentor™ II, Simbionix™ Ltd., Airport City, Israel) to create five tasks and metrics. Scores were designed to measure both speed and precision. Validity evidence was assessed by correlating performance with self-reported endoscopic experience (surgeons and gastroenterologists [GIs]). Internal consistency of each test task was assessed using Cronbach’s alpha. Test–retest reliability was determined by having the same participant perform the test a second time and comparing their scores. Passing scores were determined by a contrasting groups methodology and use of receiver operating characteristic curves.nResultsA total of 160 participants (17xa0% GIs) performed the simulator test. Scores on the five tasks showed good internal consistency reliability and all had significant correlations with endoscopic experience. Total FES scores correlated 0.73, with participants’ level of endoscopic experience providing evidence of their validity, and their internal consistency reliability (Cronbach’s alpha) was 0.82. Test–retest reliability was assessed in 11 participants, and the intraclass correlation was 0.85. The passing score was determined and is estimated to have a sensitivity (true positive rate) of 0.81 and a 1-specificity (false positive rate) of 0.21.ConclusionsThe FES hands-on skills test examines the basic procedural components required to perform safe flexible endoscopy. It meets rigorous standards of reliability and validity required for high-stakes examinations, and, together with the knowledge component, may help contribute to the definition and determination of competence in endoscopy.

Tc-99m-IDA gallbladder kinetics and response to CCK in chronic cholecystitis

The cholecystographic pattern and the contractile response of the gallbladder (GB) to cholecystokinin (CCK) were studied in 101 consecutive patients with uncomplicated chronic cholecystitis confirmed by pathology. Sequential GB images were obtained after administration of 5 mCi 99mTc-Disofenin and the ejection fraction was determined following a 15 min infusion of CCK. Sixteen of 101 (16%) GB failed to visualize upto 4 h; of the remaining patients, 3/85 (4%) showed delayed visualization beyond 1 h, and 82/85 visualized within 1 h. The mean ejection fraction (EF) in 67 patients was 56.9%±27.5% compared to 74.8%±19.8% in a normal control group of 27 subjects (P0.005). However, there was a large overlap as 76% of chronic cholecystitis patients had EF values falling within the full normal range. GB disease could be identified with confidence when the EF was less than 35%, i.e. below the 2 standard deviation range of normal. On the basis of radionuclide kinetic studies alone, the majority of patients with chronic cholecystitis cannot be distinguished from normal.

A New Paradigm for Surgical Procedural Training

xternal forces continue to exert enormous pressures on surgical care. ational mandates regarding quality, safety, and outcomes of patient care, oupled with concerns about health care costs and demands for greater ransparency, present a host of challenges and exciting opportunities. The ivotal role of education in addressing these imperatives has been rticulated in major reports. Steps are being taken to introduce ignificant changes in existing models of teaching, learning, and assessent; however, more needs to be done to create high-performance earning organizations with a different ethos. This will require fundamenal redesign of education and training models that have borne us in good tead for more than 100 years. Recent advances in the science and ractice of surgical education and training provide a solid foundation on hich new models should be built to positively impact outcomes of urgical care and address the array of national imperatives. This article rovides a synopsis of the challenges and opportunities relating to urgical education and training, outlines the role of simulation, undercores the importance of simulation centers as core facilities through hich new education and training models may be developed and isseminated, and highlights the innovative education and training prorams of the American College of Surgeons (ACS).

Nifedipine inhibits cholecystokinin-induced gallbladder contraction

Nifedipine is a calcium channel blocker which results in relaxation of smooth muscle. Although it has been utilized clinically to treat cardiovascular disease, and more recently spastic disorders of the esophagus and colon, its effects on gallbladder contractility have not been clearly defined. We tested the effects of nifedipine on gallbladder contraction stimulated by cholecystokinin (CCK) in a conscious guinea pig model and in healthy human volunteers. Gallbladder contraction was measured in response to repeated injections of CCK before and after intravenous nifedipine given to groups of five guinea pigs in a dose of 100, 200, or 300 μg. Nifedipine virtually abolished spontaneous interdigestive gallbladder contractile activity and decreased resting gallbladder tone. The mean amplitude of gallbladder contraction in response to CCK was decreased by 45, 73, and 67% (P < 0.01), in response to the nifedipine doses of 100, 200, and 300 μg, respectively. The integrated gallbladder contractile response and the rate of rise of gallbladder pressure in response to CCK were also significantly decreased by nifedipine. In nine healthy human volunteers, gallbladder emptying was measured by radionuclide cholescintigraphy in response to CCK infusion; on another day the study was repeated after oral administration of 10 mg nifedipine. Ejection fraction was significantly decreased by nifedipine from 72 ± 5 to 51 ± 5% (P < 0.001). These data demonstrate that nifedipine is a potent inhibitor of gallbladder contractility in guinea pigs and man. This may provide the basis for the use of nifedipine clinically in the treatment of biliary colic and also raises questions about the potential effect of longterm nifedipine use on gallstone formation and cholecystitis.

Why fundamentals of endoscopic surgery (FES)

As flexible endoscopy has moved into the mainstream, gastroenterologists have embraced many of the skills and techniques particular to this modality of diagnosis and intervention. Their adoption of flexible endoscopic technology and training, and the lack of enthusiasm for endoscopic therapy potentials by surgeons, has left many surgical residents and practicing surgeons deficient in endoscopic skills. As a result, education of surgical residents in flexible endoscopy has lagged and training of surgical residents in flexible endoscopy is increasingly coming under scrutiny and has become an area of debate. The medical literature and practice guidelines are replete with articles from surgeons and gastroenterologists debating the appropriate education and training in flexible endoscopy. Both surgical and gastroenterology professional societies have published guidelines for training in flexible endoscopy. These guidelines are often at odds with each other, citing opposing literature supporting their position on appropriate criteria for training in basic upper and lower endoscopy [1–4]. Flexible endoscopy is a critical element of any general surgeon’s and colorectal surgeon’s practice. In 2007, 74 % of rural surgeons performed more than 50 flexible endoscopic procedures each year, with 42 % of rural surgeons performing more than 200 flexible endoscopic procedures annually [5]. In a 2010 report on rural, under-served areas that lack gastroenterology services, 39.8 % of an American general surgeons’ practice comprises flexible endoscopic procedures [6]. In Canada, surgeons were found to be the primary providers of flexible endoscopic services in smaller urban and rural areas [7]. The American Board of Surgery (ABS) has begun to address the training inequity that exists between general surgery residents and gastroenterology fellows [8]. In an effort to ensure surgical residents are fully trained and competent in flexible endoscopy, the ABS has not only increased the minimum requirements for training general surgery residents in flexible endoscopy but has also undertaken the task of formalizing a flexible endoscopy curriculum for its residents. Currently, the ABS and Residency Review Committee (RRC) recommend 35 upper endoscopic procedures and 50 colonoscopies as the minimum number of procedures to be performed by surgical residents. The Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) and the ABS have long espoused that numbers do not ensure competency in surgical or endoscopic procedures. This position is fully supported by data. In 2004, the SAGES esophagogastroduodenoscopy (EGD) Outcomes Study Group prospectively reviewed 3,525 EGDs performed by surgeons, showing a high degree of success with low morbidity. There was no correlation between experience (i.e. number of cases performed) and completion rates or major complications [9]. A similar trial by the SAGES Colonoscopy Study Outcomes Group prospectively reviewed 13,580 colonoscopies performed by surgeons and found no correlation between experience and complications, with an acceptable success rate. The investigators noted that a minimum of 50 colonoscopies with 100 performed annually showed a significant improvement in completion rates Taskforce Members are listed in Appendix.

Costs and Effectiveness of Extracorporeal Gallbladder Stone Shock Wave Lithotripsy Versus Laparoscopic Cholecystectomy: A Randomized Clinical Trial

Thirty-five patients were randomized to extracorporeal shock-wave lithotripsy (ESWL) and 25 to laparoscopic cholecystectomy (LC). Stone disappearance occurred in only 12 of 32 ESWL patients [38% (95% CI: 21-56%)] during a 15-month follow-up. Greater incremental gains in quality of life after 6 months were observed among LC patients (p < .01). Total duration of disability was 6.8 +/- 8.5 days for ESWL, and 22.7 +/- 16.6 days for LC (p < .01). Nine (28%) patients crossed over electively to the LC group, but only 44% of these underwent LC within the next 3 years. ESWL cost Can

Simulators for Laparoscopic Surgery: A Coming of Age

58.9/ day of disability saved. ESWL is limited by its selective applicability and modest stone disappearance rate. Its cost-effectiveness is largely dependent on patient acceptance of recurrent episodes of biliary colic due to the persistence of stone fragments.