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PubMed1995

[The anatomical correction of transposition of the great arteries in the neonatal period].

INTRODUCTION AND OBJECTIVES: Anatomic correction of transposition of the great arteries in simple and complex form is theoretically the only procedure which offers the possibility of real cure to the problem. We report there our operative results and mid-term follow-up with this approach. METHODS: From June 1989 to February 1994, anatomical surgical correction was performed in 41 patients in the neonatal period, 31 with simple TGA and 9 patients with transposition associated with ventricular septal defect. We report our preoperative management, anatomic findings and surgical technique. RESULTS: Our initial experience with the arterial repair was associated with a high operative mortality. The actuarial survival rate was 74% at 56 months. Hospital mortality of the last 31 patients was 12.9%. Intermediate-term follow-up was 18 months. No late deaths. One patient underwent reoperation for supravalvular pulmonary stenosis. All survivors are in functional class I. The only significant risk factor of in-hospital mortality was the time of surgery (learning curve). CONCLUSION: The initial experience with arterial repair is associated with a difficult learning curve. Primary repair must be performed during the newborn period in simple and complex transpositions. Mid-term results are very encouraging. Longer follow-up is necessary to secure this technique and to render obsolete all other types of repair.

Aortic Coarctation↗

PubMed1989

The impact of learning on cost: the case of heart transplantation.

The effect of increased experience on outcomes is evaluated for a heart transplantation program. While previous research on surgical procedures has documented a strong and consistent relationship between experience and quality (mortality and complication rates), little correlation has been found between experience and cost. Most of this research has relied on comparisons between different-sized programs at the same point in time, making it difficult to interpret. The lack of clear financial incentives in the past may also have muted a relationship between cost and experience that has been consistently documented and used in planning the production of almost all other non-health-related goods and services. The traditional operations research or managerial accounting model for projecting the impact of learning on four measures of cumulative average resource consumption (death rates, length of stay, billing units, and charges), modified to include a lower limit, was applied to the experience of a heart transplant program. The data fit the model well. The slope of the learning curve is steepest for death rates and flattest for charges. Possible implications of such learning curves on the strategic thinking of institutions and the planning and management of health services are discussed.

Clinical Competence↗

PubMed1996

Adaptation motor learning of arm movements in patients with cerebellar disease.

OBJECTIVE: To design a test of motor learning using arm movements in normal subjects and patients with cerebellar disease. METHODS: Elbow angle was continuously displayed as a cursor (a dot) on a computer screen, and subjects made ballistic elbow flexion and extension movements to try to move the cursor between two targets on the screen. The relation between the arm movement and its visual feedback was changed, and the subjects reacted by adapting the amplitude of their movements in subsequent trials. RESULTS: The consecutive errors showed exponential learning curves during adaptation, which were quantified by their steepness. Ten patients with isolated cerebellar or olivopontocerebellar degeneration had less steep learning curves than normal subjects, indicating a failure of adaptation motor learning in cerebellar disease. The results show that this test may be useful for the analysis of motor learning.

Adaptation, Physiological↗

PubMed1998

Learning manual skills in anesthesiology: Is there a recommended number of cases for anesthetic procedures?

UNLABELLED: The learning process is a multidimensional function with a wide intra- and interindividual scattering. To determine the learning process in anesthesia, we evaluated 11 first-year residents according to their rate of success or failure when applying manual anesthesiological skills, such as performance of spinal, epidural, or brachial plexus anesthesia and tracheal intubation or insertion of an arterial line. Epidural anesthesia was the most difficult procedure (P < 0.05). Significant differences were found between epidural anesthesia and tracheal intubation (P < 0.05), insertion of an arterial line (P < 0.05), and brachial plexus block (P < 0.05), as well as between spinal anesthesia and orotracheal intubation (P < 0.05). Learning curves are a valid tool for monitoring institutional and individual success. IMPLICATIONS: To investigate the learning process in anesthesia, typical anesthetic procedures were performed by inexperienced residents during their first year. Learning curves were generated for each procedure performed. Epidural anesthesia was the most difficult procedure to perform (P < 0.05).

Anesthesia, Epidural↗

PubMed1996

["Tension-free" repair of inguinal hernia: laparoscopic (TAPP) versus open (Lichtenstein) repair].

In a prospective study, from June 1992 to February 1994 94 patients with 100 hernias were treated laparoscopically (TAPP) and from March 1993 to November 1994 100 patients with 108 hernias were treated with a Lichtenstein patch. Concerning duration of operation, postoperative outcome, complications and return to work, only minor differences were noted. Because of the more demanding and difficult technique, all TAPP procedures were performed by one surgeon, whereas all 11 surgeons of the department performed the Lichtenstein procedure without any learning curve, which demonstrates the simplicity of the procedure. A higher recurrence rate was found for the TAPP procedure (8 vs 0), however the learning curve has to be considered. The Lichtenstein operation is easy to learn and perform, safe, efficient, cheaper (750 DM) and therefore superior to the TAPP procedure. A planned randomized study was cancelled; laparoscopic hernia repair is no longer carried out in our department.

Adult↗

PubMed2003

Laparoscopic Roux-en-Y gastric bypass: initial 2-year experience.

BACKGROUND: Roux-en-Y gastric bypass (RYGBP)-essentially a restrictive bariatric procedure-is currently considered the gold standard for the surgical treatment of morbid obesity. Open surgery in obese patients is associated with a high risk of cardiopulmonary complications, wound infection, and late incisional hernia. Laparoscopic surgery has been shown to reduce perioperative morbidity and to improve postoperative recovery for various procedures. Herein we present our results with laparoscopic RYGBP after an initial 2-year experience. METHODS: A prospective database was created in our department beginning without the first laparoscopic bariatric procedure. To provide a complete follow-up of 6 months, the results of all patients operated on between June 1999 and August 2001 were reviewed. Early surgical results, weight loss, correction of comorbidities, and improvement of quality of life were evaluated. RESULTS: A total of 107 patients were included. There were 82 women and 25 men, with a mean age of 39.7 years (range, 19-58). RYGBP was a primary procedure in 80 cases (49 morbidly obese and 31 superobese patients) and a reoperation after failure or complication of another bariatric operation in 27 cases. Mean duration of surgery was 168 min for morbidly obese patients, 196 min for surperobese patients, and 205 min for reoperated patients (p <0.01). Conversion to open surgery was necessary in two cases. A total of 22 patients (20.5%) developed complication. Nine of them (8.4%) required reoperation for leak (five cases, or 4.6%), bowel occlusion (three cases, or 2.8%), or subphrenic abscess (one case, or 0.9%). mortality was 0.9%. Major morbidity decreased over time (first two-thirds, 12.5%, last third, 2.7%). major morbidity decreased over time (first two-thirds, 12.5%; last third, 2.7%). Excess weight loss of -50% was achieved in >80% of the patients, corresponding to a loss of 15 body mass index (BMI) units in morbidly obese patients and 20 BMI units in superobese patients. In the vast majority of patients, comorbidities improved or disappeared over time and quality of life improved. CONCLUSIONS: Laparoscopic Roux-en-Y gastric bypass is feasible, but it is a very complex operation. Indeed, it is associated with a long and steep learning curve, as reflected in the high number of major complications among our first 70 patients. The learning curve probably includes between 100 and 150 patients. With increasing experience, the morbidity rate becomes more acceptable and comparable to that of open RYGBP. The results in terms of weight loss and correction of comorbidities are similar to those obtained after open surgery, at least in the short term. However, only surgeons with extensive experience in advanced laparoscopic as well as bariatric surgery should attempt this procedure.

Adult↗

PubMed1985

Visually and acoustically augmented performance feedback as an aid in motor control learning: a study of selected components of the rowing action.

The present work compares the efficiency of two training techniques as aids to learning selected aspects of a sequentially ordered action such as that of rowing. Subjects in one group were trained with a conventional learning technique (CLT) while those in a second group were trained by an augmented feedback technique referred to as external feedback (EFB). Progress was recorded on learning curves. Rowing athletes with limited experience and psychophysiology students were used for the study. The tasks consisted of learning movement timing (rhythmicity of action and coordination of body parts) and movement intensity (force and electromyogram development), in four separate experiments. The learning curves for EFB subjects were found to have significantly and consistently higher slopes than those for CLT subjects. Optimal criteria were reached by EBF subjects, after a continuous increase in performance levels and a concomitant decrease in standard deviations evaluated from periodicity, movement accuracy and force. Subjects, who after 8 to 10 sessions of CLT learning had not reached optimal level, were exposed to EFB. Their performances then showed a marked improvement and attained the required criterion in 2 to 4 sessions. This further demonstrates the efficacy of EFB as compared with CLT, as an aid to learning a complex sensorimotor action. The efficacy of EFB as a learning technique is discussed in relation to the internal model of the task to be executed and to sensory motor control and motor programmes.

Adult↗

PubMed1996

Recency effect in multiple sclerosis.

The main object of this study was to test acquisition-retrieval deficits in multiple sclerosis (MS) patients A Spanish version of the Rey Auditory-Verbal Test (RAVLT) (Rey 1964) was used with an MS group (n=10 subjects) and a control group (n=10) Different measurements were obtained with the RAVLT memory span, a learning curve, and a curve of serial position of words The results revealed no differences between groups in memory span and learning curve, but significant differences were found in the curve of serial position No revency effect in the immediate form of theRAVLT was seen These results are discussed with reference to the work of Baddelaey and Hitch (1993) regarding recency effects and related literature on the acquisition-retrieval deficits in MS patients.

Journal Article↗

PubMed2005

Total laparoscopic abdominal aortic aneurysms repair.

AIM: The aim of the study was to describe our experience of total laparoscopic abdominal aortic aneurysm (AAA) repair. METHODS: Between February 2002 and September 2004, we performed 49 total laparoscopic AAA repair in 45 men and 4 women. Median age was 73 years (range, 46-85 years). Median aneurysm size was 52 mm (range, 30-95 mm). ASA class of patients was II, III and IV in 16, 32 and 1 cases, respectively. We used the laparoscopic transperitoneal left retrocolic approach in 47 patients. Seven patients were operated via a tranperitoneal left retrorenal approach and one patient via a retroperitoneoscopic approach. RESULTS: We implanted tube grafts and bifurcated grafts in 19 and 30 patients, respectively. Median operative time was 290 min (range, 160-420 min). Median clamping time was 81.5 min (range, 35-230 min). Median blood loss was 1800 cc (range, 300-6900 cc). Mortality was 6.1% (3 patients). In our early experience, two patients died of myocardial infarction. The 3rd death was due to a multiple organ failure. Thirteen major non lethal postoperative complications were observed in 9 patients (18%). Four patients had local/vascular complications, which required reintervention (8%). Nasogastric tube is now removed at the end of procedure. Median duration of ileus, return to general diet, ambulation and hospital stay were 2, 3, 3 and 10 days. With a median follow-up of 19 months (range, 8-39 months), complete recovery with patent graft was observed in 44 patients. Two patients needed a crossover femoral graft for one iliac dissection and one graft limb occlusion. CONCLUSIONS: These results show that total laparoscopic AAA repair is feasible and worthwhile for patients once the learning curve is overcome. It remains technically demanding and a previous training in videoscopic sutures is essential. Initial learning curve in laparoscopic aortic surgery with aortoiliac occlusive lesions is preferable before to begin laparoscopic AAA repair.

Aged↗

PubMed2006

Virtual reality simulation training can improve technical skills during laparoscopic salpingectomy for ectopic pregnancy.

OBJECTIVES: To assess the first commercially available virtual reality (VR) simulator to incorporate procedural modules for training of inexperienced gynaecological surgeons to perform laparoscopic salpingectomy for ectopic pregnancy. DESIGN: Prospective cohort study. SETTING: Departments of surgery and gynaecology in central London teaching hospitals. SAMPLE: Thirty gynaecological surgeons were recruited to the study, and were divided into novice (<10 laparoscopic procedures), intermediate (20-50) and experienced (>100) groups. METHODS: All subjects were orientated to the VR simulator with a basic skills task, followed by performing ten repetitions of the virtual ectopic pregnancy module, in a distributed manner. MAIN OUTCOME MEASURES: Operative performance was assessed by the time taken to perform surgery, blood loss and total instrument path length. RESULTS: There were significant differences between the groups at the second repetition of the ectopic module for time taken (median 551.1 versus 401.2 versus 249.2 seconds, P = 0.001), total blood loss (median 304.2 versus 187.4 versus 123.3 ml, P = 0.031) and total instrument path length (median 17.8 versus 8.3 versus 6.8 m, P = 0.023). The learning curves of the experienced operators plateaued at the second session, although greater numbers of sessions were necessary for intermediate (seven) and novice (nine) surgeons to achieve similar levels of skill. CONCLUSIONS: Gynaecological surgeons with minimal laparoscopic experience can improve their skills during short-phase training on a VR procedural module. In contrast, experienced operators showed nonsignificant improvements. Thus, VR simulation may be useful for the early part of the learning curve for surgeons who wish to learn to perform laparoscopic salpingectomy for ectopic pregnancy.

Clinical Competence↗

PubMed2001

Laparoscopic surgery for morbid obesity.

Minimally invasive approaches to bariatric surgery offer significant advantages over those of open surgery. The potential of laparoscopic approaches to reduce the morbidity of these operations may exceed that of laparoscopic cholecystecomy and laparoscopic Nissen fundoplication because the access incisions for open bariatric operations have relatively greater potential for harming the morbidly obese patient. Early results of laparoscopic VBG suggest a significant decrease in perioperative morbidity compared to the open approach, with similar weight-loss results. LGB may have the lowest perioperative morbidity and mortality of all current bariatric operations. However, the reoperation rate for device-related complications or failure of the patient to lose sufficient weight appears significant. Long-term esophageal motility also remains questionable for the LGB. It is hoped that the FDA trial will address many of the issues regarding LGB. Results of Lap RYGBP are accumulating and appear promising. The early experience suggests that it is technically feasible and safe in the hands of surgeons who have appropriate training. It is associated with low perioperative morbidity, short hospital stay, and rapid recovery compared to expected results of open RYGBP. Weight loss for Lap RYGBP after 5 years is excellent. It is, however, a technically formidable operation requiring long operating times and a steep learning curve. Early results indicate that technical complications may be greater than those experienced with open RYGBP because of the learning curve. Lap RYGBP is a promising bariatric procedure with potentially significant advantages over open RYGBP. Thus, for patients in the United States, Lap RYGBP may become the preferred weight-reduction procedure. The value of hand-assisted bariatric procedures and laparoscopic malabsorption procedures must await further study.

Anastomosis, Roux-en-Y↗

PubMed2003

Transradial coronary angiography and intervention.

OBJECTIVE: Transradial cardiac catheterization promises fewer access site complications and improved patient comfort due to immediate ambulation. However, the use of miniaturized systems and the presence of a steep learning curve have discouraged the acceptance of transradial catheterization. The purpose of this study was to assess the applicability and learning curve of transradial catheterization in the Saudi population for operators without prior experience in this approach. METHODS: The study was performed at the King Fahd Armed Forces Hospital, Jeddah, Kingdom of Saudi Arabia between June 2001 and January 2003. Right radial artery cannulation was performed and standard 5 French (F) femoral curve catheters for angiography and standard 6F guiding catheters were used for intervention. The first 101 patients comprised group 1 and the subsequent 101 patients comprised group 2. RESULTS: Two hundred and two patients underwent transradial catheterization (diagnostic alone in 49%, intervention alone in 10%, and diagnostic plus intervention in 41%). The procedure was successful in 191 patients (95%). The success rate was higher (99% versus 90%, p=0.013), and the mean diagnostic catheterization time was lower (28 versus 20 minutes, p=0.013) in group 2 patients compared with group one patients. There were no vascular or ischemic complications. CONCLUSION: Transradial catheterization is safe and feasible for diagnostic and interventional procedures. With experience, the success rates and the procedural times have both improved.

Adult↗

PubMed2006

A simple and inexpensive method of preoperative computer imaging for rhinoplasty.

UNLABELLED: GOALS/PURPOSE: Despite concerns of legal liability, preoperative computer imaging has become a popular tool for the plastic surgeon. The ability to project possible surgical outcomes can facilitate communication between the patient and surgeon. It can be an effective tool in the education and training of residents. Unfortunately, these imaging programs are expensive and have a steep learning curve. The purpose of this paper is to present a relatively inexpensive method of preoperative computer imaging with a reasonable learning curve. MATERIALS AND METHODS: The price of currently available imaging programs was acquired through an online search, and inquiries were made to the software distributors. Their prices were compared to Adobe PhotoShop, which has special filters called "liquify" and "photocopy." It was used in the preoperative computer planning of 2 patients who presented for rhinoplasty at our institution. Projected images were created based on harmonious discussions between the patient and physician. Importantly, these images were presented to the patient as potential results, with no guarantees as to actual outcomes. RESULTS: Adobe PhotoShop can be purchased for 900-5800 dollars less than the leading computer imaging software for cosmetic rhinoplasty. Effective projected images were created using the "liquify" and "photocopy" filters in PhotoShop. Both patients had surgical planning and operations based on these images. They were satisfied with the results. CONCLUSIONS: Preoperative computer imaging can be a very effective tool for the plastic surgeon by providing improved physician-patient communication, increased patient confidence, and enhanced surgical planning. Adobe PhotoShop is a relatively inexpensive program that can provide these benefits using only 1 or 2 features.

Adult↗

PubMed2001

The stability of validity coefficients over time: Ackerman's (1988) model and the general aptitude test battery.

This study examined P. L. Ackerman's (1988) model of skill acquisition within an applied setting. Differences were examined between jobs on the basis of task consistency: changes in performance variability across experience, learning curves, and stability of ability-performance correlations across experience. Results showed the degree of task consistency influenced the shape of learning curves, with jobs composed of primarily consistent tasks improving more rapidly and reaching asymptote sooner. In addition, trends in ability-performance correlations were moderated by the degree of task consistency within ajob. Specifically, forjobs with primarily consistent tasks, general cognitive ability best predicted early performance whereas psychomotor ability best predicted later performance. In contrast, general cognitive ability was the strongest predictor across experience for jobs with primarily inconsistent tasks.

Aptitude Tests↗

PubMed2005

Effects of stimulus structure and target-distracter similarity on the development of visual memory representations in schizophrenia.

INTRODUCTION: In a previous study (Silverstein, Bakshi, Chapman, & Nowlis, 1998a, Cognitive Neuropsychiatry) we demonstrated that while schizophrenia patients showed similar learning curves as nonpatient controls when determining whether a configural pattern of elements has been seen before or not, they did not demonstrate any learning curve with nonconfigural stimuli (in contrast to controls). Methodological limitations of that study, however, precluded generalisability of those effects. METHODS: In the present study, therefore, different groups of schizophrenia patients (n = 18) and controls (n = 22) were administered a modified version of the familiarity judgement task used in Silverstein et al. (1998a). In the new version of the task: (1) the patterns that repeated were different for each participant; and (2) half of the nonrepeating patterns were configural and half were nonconfigural. RESULTS: These indicated stronger perceptual learning effects for the configural compared to the nonconfigural patterns, and overall better performance and more pronounced learning effects for the control group. CONCLUSIONS: The data provide further evidence for a schizophrenia-related impairment in perceptual organisation and in the ability to develop memory representations for novel stimuli.

Journal Article↗

PubMed2000

[Value of multimedia educational software in training of the paranasal sinus surgeon].

BACKGROUND: When starting sinus surgery, every surgeon has to pass through an individual learning curve. To avoid complications, costly, time-consuming surveillance is necessary. We wanted to analyse the impact of multimedial teaching software on the learning curve. METHODS: A total of 1104 operations performed by four surgeons were evaluated. The first consecutive 200 operations by each surgeon were analyzed according to their complications. After revaluating the general phases of surgical development, we compared the first 90 operations by another group of four surgeons who had undergone training with the teaching program. RESULTS: Cauterization of the anterior ethmoidal anterior was nearly the same in both groups (10/8). Injuries of the dura dropped from 5 to 2, and periorbital lesions were reduced significantly from 20 to 5 (p < 0.001). CONCLUSIONS: Multimedial learning programs can reduce complications effectively and form a valuable part training.

Chronic Disease↗

PubMed2006

Importance of perioperative processes of care for length of hospital stay after laparoscopic surgery.

BACKGROUND AND PURPOSE: The technologic imperative has prompted the adoption of complex laparoscopic techniques by physicians with various degrees of skill. We sought to measure the impact of both case mix and physician practice (perioperative process/risk factors) on length of stay (LOS)-a common benchmark- after laparoscopic surgery. PATIENTS AND METHODS: We identified 911 patients undergoing laparoscopic retroperitoneal surgery between 1996 and 2004, who comprise our study population. Patients remaining in the hospital >5 days-the 90th percentile for the sample-were classified as having a prolonged LOS. Adjusted models were developed to determine the independent association of case mix and process measures with a prolonged LOS. The likelihood ratio test was used to discern the improvement of fit of the process model compared with the case-mix model. RESULTS: Among factors related to case mix and structure of care, increasing age (odds ratio [OR] 1.1; 95% CI 1.0, 1.2), less surgeon experience (OR 6.1; 95% CI 2.1, 17.2), male gender (OR 2.1; 95% CI 1.2, 4.0), and American Society of Anesthesiologists score of 3 or 4 (OR 7.2; 95% CI 2.2, 23.3) were independently associated with a prolonged LOS. The need for a transfusion (OR 9.4; 95% CI 33.9, 23.2), the development of a postoperative complication (OR 4.6; 95% CI 2.2, 9.5), and longer operative time (OR 1.5; 95% CI 1.3, 1.8) explained additional variation in prolonged LOS outcomes when considering perioperative process/risk factors in the model. Perioperative factors significantly improved the fit of the model (chi (2) statistic 101.8; p < 0.0001). CONCLUSIONS: Significant variation in outcomes is explained by factors describing aspects of surgical expertise. Variability in the surgical skill set is likely greatest during the laparoscopic learning curve, which raises a quality-of-care concern during the initial implementation of the technique. Policies attempting to smooth the laparoscopic learning curve, such as mentoring and skill measurement prior to credentialing, could improve the quality of care.

Aged↗

PubMed2001

Learning manual skills in spinal anesthesia and orotracheal intubation: is there any recommended number of cases for anesthesia residency training program?

Wide variability exists in the number of anesthetic procedures to which anesthesia residents are exposed during their training. The number of attempts at various procedures before a trainee becomes proficient at performing each anesthetic procedure is not known. To determine the learning process of 150 attempts of spinal anesthesia and 100 attempts of orotracheal intubation, the two most frequent anesthetic procedures, we evaluated 9 first-year anesthesia residents according to their rate of success or failure. The learning curves of both procedures revealed an initial rapid improvement of success during the first 20 attempts. Spinal anesthesia was more difficult to learn (p=0.0002) but the learning curves of spinal anesthesia and orotracheal intubation reached a nondifferent high success rate of 82 per cent and 88.9 per cent respectively (p=0.13). According to this study the institutional recommended number of cases for spinal anesthesia and orotracheal intubation were 112 and 27 cases respectively.

Adult↗