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PubMed2006

What is the learning curve associated with double-balloon enteroscopy? Technical details and early experience in 6 U.S. tertiary care centers.

BACKGROUND: Performance parameters for double-balloon enteroscopy (DBE) have not been described. OBJECTIVE: To determine the learning curve for DBE. DESIGN: Prospective cohort study. SETTING: Six U.S. tertiary centers. PATIENTS: A total of 188 subjects undergoing 237 DBE procedures; 130 (69%) with obscure GI bleeding. INTERVENTIONS: Performance parameters from each center's initial 10 cases were compared to the subsequent examinations. MAIN OUTCOME MEASUREMENTS: Exam duration, depth of insertion, and findings on DBE examination. RESULTS: DBE was introduced by mouth in 149 (63%) cases, by rectum in 77 (33%) cases, and through a stoma in 6 (2.5%) patients. The mean (+/-SD) duration was 109.1 +/- 44.6 minutes for the first 10 cases and 92.4 +/- 37.6 minutes for subsequent cases (P = .005) but did not change for rectal DBE procedures. There was no change in mean depth of insertion, but the mean fluoroscopy time declined significantly (P = .025). Diagnostic or therapeutic maneuvers were performed in 64% of cases; DBE led to a diagnosis in 81 (43%) patients. A total of 78% of patients had prior capsule endoscopy (CE) with significant agreement between DBE and CE (kappa = 0.74). One perforation occurred (0.4%). Per-rectal cases failed to reach the small bowel in 24 (31%) cases. LIMITATIONS: All patients did not undergo initial CE. The therapeutic DBE scope was not available for the initial 8 months of the study. CONCLUSIONS: There was a significant decline in overall procedural time and fluoroscopy time after the initial 10 DBE cases. There was no improvement in performance parameters when DBE was performed via the rectal approach despite increased, but limited, operator experience.

Adolescent↗

PubMed1996

The learning curve for acoustic tumor surgery.

Although operative experience is considered to be critically important in the surgical management of acoustic tumors, little objective evidence substantiates this claim. The present study was undertaken to determine whether a learning curve exists for acoustic tumor surgery. The first 96 acoustic tumor patients managed surgically by a new neurotologic team were retrospectively reviewed. A significant improvement (P<.0003; F=6.32) in the ability to achieve good (grade II or better) postoperative facial nerve function was identified. Improving trends for complete resection rate and hearing preservation were documented, and the incidence of cerebrospinal fluid (CSF) leaks declined; however, statistical significance was not achieved. For postoperative facial nerve function, approximately 60 cases were necessary before the new team achieved results similar to those of highly experienced surgeons. The frequencies of complete resection, CSF leaks, hearing preservation, stroke, and mortality were comparable to those of experienced neurotologic teams. The findings of this study may have implications for both patient care and physician training.

Clinical Competence↗

PubMed2006

Learning curve using robotic surgery.

The da Vinci (Intuitive Surgical, Inc., Sunnyvale, CA) surgical system is being used by an increasing number of surgeons across several surgical specialties. The robotic interface is different not only to open surgery, but also to laparoscopy because it involves remote surgical control, stereoscopic vision, and lack of haptic feedback. As the transition is made from traditional open to robotic surgery, factors such as learning of robotic skills, assessment of proficiency in robotics, and structured training for urologists in practice and residents assumes importance. Understanding how the robotic surgical technique is learned and how such learning can be best assessed will enable us to define protocols for training and set standards for proficiency. Learning curve and surgical dexterity are two parameters that are used to compare surgical learning and training. This article presents the current gold standard for assessing skill training and compares surgical skill acquisition and proficiency using conventional laparoscopy and robotic interfaces.

Clinical Competence↗

PubMed2006

A learning curve for endoscopic submucosal dissection of gastric epithelial neoplasms.

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) has become a widely accepted method for treating gastrointestinal neoplasms. The objective of our study was to assess the learning curve for ESD of gastric epithelial neoplasms. PATIENTS AND METHODS: Clinicopathological data were retrospectively collected from 383 ESD procedures for gastric epithelial neoplasms that were performed over a 5-year period. Thirteen endoscopists were involved as operators during this period. In study 1, the performance of the two principal operators was assessed every 25 patients. In study 2, the performance of all 13 operators was assessed according to their experience. RESULTS: In study 1, the caseloads of the two principal operators were 188 and 118 ESD procedures. There were no significant differences found between successive groups of 25 patients with regard to en-bloc resection rate and bleeding and perforation complication rates. The size of the lesions and the resected specimen diameter increased significantly as the number of treated cases increased, whereas the average procedure time decreased significantly. In study 2, the operators' caseloads ranged from 1 to 188 cases, with 11/13 operators having experience of fewer than 30 cases. There was no significant difference in treatment efficacy and complication rates between the operators throughout the study period. The lesions were mainly located in the lower part of the stomach in the procedures performed by the 11 less experienced endoscopists. The procedure times shortened as experience in the method increased. CONCLUSIONS: Constant rates of both treatment efficacy and complications were achieved over a 5-year period of experience with ESD. A decrease in procedure time was found to be a marker of proficiency in this technique.

Clinical Competence↗

PubMed1997

The learning curve associated with laparoscopic antireflux surgery in infants and children.

Laparoscopic fundoplication is an effective method for treating gastroesophageal reflux in infants and children. Some surgeons prefer the traditional open technique and have concerns regarding complications associated with laparoscopic surgery as well as the time length of operation. This report addresses these concerns in a retrospective review of the first 160 consecutive pediatric patients who underwent laparoscopic fundoplication. "Learning Curves" as a function of surgical experience are presented highlighting some of the lessons learned while developing the laparoscopic fundoplication technique.

Adolescent↗

PubMed2000

Steep learning curve of laparoscopic splenectomy.

BACKGROUND AND PURPOSE: In 1992, Ochsner Foundation Hospital was among the first institutions in which laparoscopic splenectomy was performed. The aim of this study is to review our experience and discuss the lessons learned. METHODS: A retrospective review of 33 cases of laparoscopic splenectomy for idiopathic thrombocytopenic purpura (ITP) (N = 22), autoimmune hemolytic anemia (AIHA) (5), thrombocytopenic purpura (TTP) (2), and other disorders (4) at Ochsner Foundation Hospital between 1992 and 1999 was conducted. Several measures, including rates of conversion to open splenectomy, were recorded and analyzed. RESULTS: Of the 33 cases, 26 (79%) were completed laparoscopically. Four were converted to an open procedure secondary to bleeding and three secondary to difficulty in dissection. Six conversions to open surgery were necessary during the first eight laparoscopic splenectomies and only one during our last 25 cases. Two patients required reoperations for bleeding. The average hospital stay after laparoscopic splenectomy was 2.3 days; eight patients stayed only 1 day. All of the TTP patients, 86% of the patients with ITP, and 40% of those with AIHA responded well to splenectomy. CONCLUSION: Laparoscopic splenectomy is a safe although complex procedure. Bleeding is the major complication but has been less common with experience. Even with today's technology, very large spleens are still extremely difficult to remove. With the short recovery and ready acceptance of patients and physicians, this technique is being used with increasing frequency. A significant learning curve exists for the safe completion of this challenging procedure.

Adolescent↗

PubMed2003

Laparoscopic fundoplication: learning curve and patient satisfaction.

AIMS: Laparoscopic fundoplication is now accepted as the optimal surgical option for the management of selected cases of gastro-oesophageal reflux disease. The principal aim of this study was to evaluate the learning curve experience of two consultant surgeons in the technique of laparoscopic fundoplication (LF). Additional variables assessed were total number of cases, preoperative investigations, conversion rate, duration of operation, ASA grade, morbidity, mortality, necessity of further procedures, and patient satisfaction rate. PATIENTS AND METHODS: Retrospective case-note analysis of all adult patients who underwent fundoplication under the care of two consultant general surgeons over a 3-year period from January 1997 to December 1999. RESULTS: A total of 61 patients were included, 31 males and 30 females, with a median age of 46 years (range, 21-73 years). Of the patients, 90% were either ASA 1 or 2. The mean time for which the 24-h pH < 4 was 20.5% (95% CI, 15.3-25.7). Of the 61 patients, 6 were operated on by open technique, for medical reasons and previous abdominal procedures. Out of the remaining 55 patients, 13 had to be converted (23.6%). Mean operating times were 120 min for LF, 85 min for open operation and 142 min for LF plus conversion. There was a significant decline in conversion rate with time (P < 0.002). Mortality was nil. One patient had a perforation of the cricopharyngeus secondary to insertion of a bougie. The mean length of hospital stay following the laparoscopic technique was 3.4 days compared to 8.7 days following the open technique. Overall, 59 patients (96%) were happy with the result, and the operation failed in 2 patients. Five patients (8%) needed endoscopic dilatation in the first few weeks after the operation. CONCLUSIONS: The results show that LF is a safe procedure, takes longer than open procedure, and has an acceptable morbidity. Experience with the technique reduces the need for conversion. The mean length of hospital stay is significantly less and there is a high level of patient satisfaction.

Adult↗

PubMed2005

Assessing the learning curve for the acquisition of laparoscopic skills on a virtual reality simulator.

BACKGROUND: The aim of this study was to develop summary metrics and assess the construct validity for a virtual reality laparoscopic simulator (LapSim) by comparing the learning curves of three groups with different levels of laparoscopic expertise. METHODS: Three groups of subjects ('expert', 'junior', and 'naïve') underwent repeated trials on three LapSim tasks. Formulas were developed to calculate scores for efficiency ('time-error') and economy of 'motion' ('motion') using metrics generated by the software after each drill. Data (mean +/- SD) were evaluated by analysis of variance (ANOVA). Significance was set at p < 0.05. RESULTS: All three groups improved significantly from baseline to final for both 'time-error' and 'motion' scores. There were significant differences between groups in time error performances at baseline and final, due to higher scores in the 'expert' group. A significant difference in 'motion' scores was seen only at baseline. CONCLUSION: We have developed summary metrics for the LapSim that differentiate among levels of laparoscopic experience. This study also provides evidence of construct validity for the LapSim.

Adult↗

PubMed1995

Laparoscopic-assisted colectomy learning curve.

PURPOSE: The purpose of this paper is to establish the number of cases necessary to master laparoscopic removal of the left or right colon. METHODS: Data were obtained by chart review and by individually completed questionnaires. RESULTS: A total of 144 laparoscopic-assisted or intracorporeal right or left hemicolectomies were completed by four surgeons at separate institutions. Questionnaires were completed by each surgeon for each sequential hemicolectomy, and data concerning the type of surgery and total operating time were recorded. Times were plotted to diagram individual learning curves for each surgeon, and data grouping methods were used to determine the curve for each surgeon as well as for the combined data base. Learning was said to have been completed when the surgeon's operative time reached a low point and subsequently did not vary by more than 30 minutes. A total of 78 right colectomies and 66 left colectomies were completed by the group. Respectively, each surgeon appeared to learn the procedure after 16, 21, 11, and 6 cases. When the entire database was analyzed as a whole, it was shown that between 11 and 15 completed colectomies were needed for learning, after which operative times remained relatively stable. CONCLUSIONS: This analysis, using total operative time as an indication of learning, shows that approximately 11 to 15 completed laparoscopic colectomies are needed to comfortably learn this procedure.

Colectomy↗

PubMed2001

[Video-assisted parathyroidectomy: learning curve].

STUDY AIM: Minimally invasive video-assisted parathyroidectomy (MIVAP) was introduced in 1997 for the treatment of sporadic primary hyperparathyroidism (sPHPT). The study aim was to review the entire series of patients operated on in order to analyse the learning curve of this procedure. PATIENTS AND METHODS: Between February 1997 to January 2001, 185 patients underwent MIVAP. All these patients were divided into three groups: group A (GA) included 63 patients operated on between February 1997 and September 1998; group B (GB) 64 patients operated on between October 1998 and January 2000; Group C (GC) 64 patients operated on between January 2000 and January 2001. Mean operative time, complications and conversions rates of the three groups were compared. RESULTS: The three groups were well matched for age and gender. Mean operative time was significantly shorter in patients of GC (28.3 +/- 13.6 min) when compared with GA (62.3 +/- 24.6 min) and GB (48.4 +/- 18.1 min). Conversion was required in 3 cases of GA (4.8%), in 8 cases of GB (12.8%) and in 4 cases of GC (6.5%). One transient postoperative recurrent nerve palsy and 4 cases of transient postoperative hypocalcemia were observed among patients of GA. No complications were registered in the other groups. CONCLUSIONS: This study shows that with increasing experience, the operative time of MIVAP was dramatically reduced, as well as postoperative complications rate. The higher percentage of conversion in groups B and C may be explained by the fact that, with increasing experience, more difficult and ambiguous cases were operated with this technique.

Adult↗

PubMed1999

A simplified vertical reduction mammaplasty: shortening the learning curve.

Although the vertical reduction mammaplasty is effective in reducing scarring, the technique has not achieved widespread acceptance in North America. There are several reasons for this. Some believe that the vertical reduction mammaplasty is only applicable to smaller breast reductions and that the learning curve is difficult. This article describes modifications to the standard Lejour vertical reduction mammaplasty that simplify the technique and make it more reliable and easier to perform. These modifications include using a medial (or lateral) dermoglandular pedicle, not undermining the skin, using liposuction only rarely to reduce breast volume, and not using pectoralis fascia sutures; the modified technique has been used in a series of 400 vertical breast reductions. In this series, scarring was reduced and the technique was easily learned and applied. It is useful for both small and large breast reductions, with a series average of 525 g removed per breast (range, 100 to 1425 g). By using these modifications, scarring in reduction mammaplasty was effectively reduced while the nipple and areola were safely transposed on a medial or lateral dermoglandular pedicle. Incorporating these technical modifications in a vertical reduction mammaplasty is recommended as a method of improving results and limiting complications.

Adult↗

PubMed2004

Laparoscopic total extraperitoneal (TEP) inguinal hernia repair: overcoming the learning curve.

BACKGROUND: Total extraperitoneal (TEP) laparoscopic inguinal hernia repair is preferred to the transabdominal preperitoneal (TAPP) repair since it preserves peritoneal integrity. However, in general it is considered to be more difficult than the latter because of the peculiarity of anatomy and limitation of working space. Therefore it has been assigned with a "steep learning curve" that the surgeon needs to climb steadily and slowly. This paper offers a working protocol, which is aimed at reducing the steep limb of this curve. METHODS: A total of 61 patients were studied between April 2000 and September 2002. Of these, five patients had a open unilateral Stoppa's preperitoneal operation to learn the detailed anatomy of the extraperitoneal space. Thereafter, laparoscopic TEP procedure was started in the following 56 cases by P.L. In case of difficulty, the procedure was to be converted to the open preperitoneal operation only. Of the first 10 cases, five were converted to unilateral Stoppa's preperitoneal operation for various reasons, and one case was converted after 30 cases. Thus a total of 11 cases were completed by open unilateral Stoppa's preperitoneal operation and 50 cases were completed laparoscopically. The first 30 cases started initially as laparoscopic operations were analyzed in groups of 10 each and compared to another study from Netherlands (evaluating four surgeons) wherein the initial laparoscopic procedures were started with the assistance of a surgeon well experienced in laparoscopic TEP operation. RESULTS: The comparison of our first 30 cases with the Netherlands group showed that while the conversions (five cases) to open operation were higher in the first 10 cases, there were no conversions in the next 20 cases. Also, there were no complications or recurrences in the present study, in striking contrast to three recurrences and 10 complications in the comparative study. The following 26 cases were associated with no recurrence or major complication. CONCLUSION: In this study we performed a total of 11 open unilateral Stoppa's preperitoneal procedures in our attempt to learn the anatomy of this extraperitoneal space better, and in the absence of any surgeon experienced in laparoscopic TEP procedure. We were able to place a large mesh in each and every case and also recognize double hernias in six cases, thus preventing recurrences and complications. We strongly recommend a minimum of 10 open Stoppa's preperitoneal procedures, to enable a trained laparoscopic surgeon to start laparoscopic TEP operation independently and in the absence of another trained laparoscopic hernia surgeon, whose presence may not prevent complications and recurrences.

General Surgery↗

PubMed2003

The ovarian endometrioma: why is it so poorly managed? Laparoscopic treatment of large ovarian endometrioma: why such a long learning curve?

The laparoscopic management of ovarian endometrioma was reported more than 15 years ago. An anonymous survey conducted among gynaecologists in the UK showed that 50% of ovarian endometrioma are still managed by laparotomy. This surprising result is discussed emphasizing the difficulties of the learning curve, pitfalls in surgical training and mistakes of the pioneers. Endoscopic surgery will become the standard technique when all practising gynaecologic surgeons have been trained during their residency. The goal of the endoscopic surgeon should be to achieve adequate surgical treatment. Endoscopic surgery is not a technical gimmick used to avoid laparotomy and to attract patients.

Education, Medical, Continuing↗

PubMed1992

Shapes of reaction-time distributions and shapes of learning curves: a test of the instance theory of automaticity.

The instance theory assumes that automatic performance is based on single-step direct-access retrieval from memory of prior solutions to present problems. The theory predicts that the shape of the learning curve depends on the shape of the distribution of retrieval times. One can deduce from the fundamental assumptions of the theory that (1) the entire distribution of reaction times, not just the mean, will decrease as a power function of practice; (2) asymptotically, the retrieval-time distribution must be a Weibull distribution; and (3) the exponent of the Weibull, which is the parameter that determines its shape, must be the reciprocal of the exponent of the power function. These predictions were tested and mostly confirmed in 12 data sets from 2 experiments. The ability of the instance theory to predict the power law is contrasted with the ability of other theories to account for it.

Attention↗

PubMed2005

Laser lead extraction: is there a learning curve?

Laser extraction of device leads offers an attractive alternative to countertraction and electrosurgical dissection sheath, potentially increasing efficacy and reducing complications. Wider adoption of this technology depends on relative ease of use. We report the experience of a new center to define the "learning curve." We performed 76 laser lead extractions in 75 patients (age 63 +/- 17 years, 59 male) from July 2001 to January 2004. Two experienced device implanters who were novice extractors underwent a 2-day site visit to a high volume extraction center for training. Lead extractions were performed in the operating room with immediate surgical backup. The indication for extraction was infection in 39 (systemic in 15), erosion or pain in 11, and lead related or debulking in 25. Complete removal was achieved in 139 of 145 leads (14 ICD, 131 pacemaker). Partial removal (<4 cm retained) was achieved in five leads (4%), and one lead could not be extracted. Complete success was 95% in the first third of patients, 94% in the second third, and 100% in the latter third. Fluoroscopy time fell from 19 +/- 22 minute in the first third of patients to 11 +/- 8 minute in the second third to 8 +/- 4 minute in the latter third (ANOVA P = 0.02). No major complications occurred. Local bleeding required minor left subclavian vein repair in two individuals. Symptomatic venous thrombosis occurred in 3 of the first 11 cases 1-21 days after extraction, but did not occur in the next 64 consecutive patients who received a 1-month anticoagulation regimen (27% vs 0%, P < 0.001). One patient developed venous thrombosis 3 weeks following cessation of warfarin therapy. Practice guidelines reasonably recommend appropriate training prior to independent performance of lead extraction. The current study suggests that experienced device implanters with appropriate operative backup taking a limited, but intensive training program can be safe and effective at lead extraction in a short time, in part a reflection of the improved technology.

Aged↗

PubMed1994

The Learning Curve for Laparoscopically Assisted Vaginal Hysterectomy/Laparoscopic Hysterectomy

Appropriate training and experience necessary for a physician to safely perform laparoscopically assisted vaginal hysterectomy (LAVH) has been a subject of great concern. Reviewed is a 2-year experience of an accomplished endoscopist that includes 88 LAVHs. The learning curve was relatively short with the most rapid operating time and perhaps most difficult procedure encountered within the first 20 cases. After this initial experience, adaptations of basic techniques have been applicable to virtually all subsequent cases encountered. Complications were minor with a rate of 19.76%. One conversion to abdominal hysterectomy was necessary (1.15% conversion rate). The average operating time was 121 minutes with the uterine weight ranged from 60 to 740 g. Average hospital stay was 1.86 days with an average recovery time of 12.65 days. In establishing proficiency in performing LAVHs, it is the author's experience that 20 LAVH's are necessary to encounter a wide enough variation in pelvic pathology to mandate a modification of the basic surgical techniques. Thus, in establishing proficiency, it should be considered that the first 20 cases be performed under the supervision of an experienced endoscopic surgeon.

Journal Article↗

PubMed1999

The effect of the learning curve on the outcome of laparoscopic treatment for gastroesophageal reflux.

The laparoscopic treatment for gastroesophageal reflux (GR) by partial (PF) or total (TF) fundoplication is the current surgical treatment of choice after failure of appropriate medical treatment. The overall results with fundoplication include the initial learning period, during which the rate of complications, conversions, and duration of surgery and hospitalization are assumed to be greater. The aim of this study was to compare the results of laparoscopic treatment for GR in three groups of consecutive patients to determine the effect of the learning period on outcome. One hundred and fifty-six patients (88 men and 68 women) with an average age of 52.3 years (range, 18-78) were included. Surgery was indicated for failure or early relapse after the end of medical treatment or a symptomatic sliding hernia. The preoperative workup (endoscopy, barium meal, or esophageal pH monitoring) was governed by the clinical picture. The choice between TF and PF was based on the results of pH monitoring. Three groups of patients were chronologically defined. The parameters that were examined were the type of preoperative exploration, the type of fundoplication, the operative technique, the conversion rate, the mortality and morbidity rates, the duration of surgery and hospitalization, and the results at short- and medium-term follow-up. The three groups were comparable with respect to patient characteristics and the nature of their GR. All patients had an endoscopy, 91% had a barium meal, 77.5% underwent esophageal manometry, and 67% had pH monitoring. One hundred and thirty-six patients had a TF and 20 had a PF. Rossetti type TF became the reference procedure (67% in group III) and closure of the diaphragmatic crura was performed systematically in group III (100%). The duration of surgery was significantly reduced between groups I and groups II and III (140, 100, 80 minutes, respectively). The rate of conversion, due to a variety of causes, decreased from 9.8% to 3.8%, and then to 0%. The average duration of hospitalization decreased from 5.8 to 4.2 days (p = 0.01). There was no mortality and the morbidity rate decreased from 15% to 3.8%, and then to 0%. There were seven cases of relapse (4.6%), five in group I (10%) and two in group II (4%), with no cases in group III, although the follow-up in group III was shorter. There is an effect of the learning curve on the outcome of treatment for GR, and this must be taken into account in the training of surgeons (training within experienced departments and guidance during their initial interventions) and also in publications to allow a more accurate comparison of this technique with other treatments for GR.

Adolescent↗

PubMed2004

Laparoscopic Roux-en-Y gastric bypass for morbid obesity: results of our learning curve in 100 consecutive patients.

BACKGROUND: Morbid obesity requires life-long treatment, and bariatric surgery provides the best results. Among the bariatric procedures, laparoscopic Roux-en-Y gastric bypass (LRYGBP) has been considered to be superior. However, it requires advanced laparoscopic skills and a learning curve. We analyzed our results in an initial series of 100 patients. METHODS: Data of 100 consecutive patients who underwent LRYGBP for morbid obesity in a 2.5-year period were prospectively collected and analyzed with emphasis on results and complications. RESULTS: Mean age was 31+/-5 years. There were 63 woman and 37 men. Preoperative BMI was 50+/-9 kg/m(2). 33 patients were considered super-obese (BMI>50). Mean operative time was 3.8 +/- 0.7 hours. Two patients required conversion to open surgery. Mean hospital stay was 6 days. Complications occurred in 10 patients. Mortality rate was 2%. Excess body weight loss was as follows: 33 +/- 8% at 3 months (n=92), 47 +/- 2% at 6 months (n=82), 62 +/- 4% at 1 year (n= 70), 66 +/- 5% at 18 months (n= 63) and 67 +/- 8% at 2 years (n= 35). There was significant improvement in several co-morbid conditions, such as diabetes and hypertension. CONCLUSION: LRYGBP is a reproducible technique. It requires the combination of bariatric and laparoscopic expertise.

Adult↗