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PubMed2002

Titanium elastic nails for pediatric femur fractures: lessons from the learning curve.

Traditionally, the treatment of choice in managing pediatric femur fractures has been traction and casting. Newer methods have focused on earlier mobility and shorter hospitalization. Use of retrograde titanium elastic nails (TENs) can quicken stabilization while allowing enough motion at the fracture site to generate excellent callus. Since TENs were first introduced in North America, our Level 1 Pediatric Trauma Center has prospectively followed all of its TEN patients. In this article, we present lessons from the learning curve of our first 50 cases--focusing on complications and their prevention. In the course of obtaining predominately excellent results, we have learned several important principles regarding TEN preoperative planning, operative technique, and aftercare. The most common problem encountered has been irritation at the nail insertion site (18% of cases). Very proximal fractures may be more challenging; unstable fractures and fractures in larger, older children are best managed with a short period of adjunctive immobilization.

Adolescent↗

PubMed1998

[Coronary angiography by a radial artery approach: feasibility, learning curve. One operator's experience].

The aim of this study was to assess the feasibility of the radial artery approach for coronary angiography in a standard population of presumed coronary patients and to continue the assessment for a sufficiently long period of time to perfect the technique, evaluate the learning curve and prepare a randomised comparison with the femoral approach. The radial artery was used for coronary angiography in 800 patients after exclusion of about 25% of patients, mainly because of a negative Allen's maneuver. With the exception of acute myocardial infarction, there was no selection based on symptoms and transradial catheterisation was attempted irrespective of age, sex, weight or height. The representative nature of the study population was confirmed by the results of the procedure (normal: 20%, single vessel disease: 30%, double vessel disease: 26%, triple vessel disease: 18% and left main disease: 5.4%). The right radial artery was used in 94% of cases. Successful radial puncture/catheterisation was obtained in 97% of cases: 100% of left coronary arteries and 99% of right coronary arteries were catheterised, the left ventricle in 98% of cases, the internal mammary arteries in 100%, and venous bypass grafts in 95%. The average duration of the whole procedure was 19 +/- 9 minutes. This decreased regularly with operator experience and judicious choice of catheters. The best choice seemed to be a single catheter for both coronary arteries, either an Amplatz or a Champ catheter. There were two probably avoidable coronary complications and two transient neurological events but no clinically significant vascular complication. The radial artery seemed to be a good approach for routine coronary angiography and may now be compared with the femoral approach. It should help expand the practice of ambulatory coronary angiography.

Aged↗

PubMed1999

The learning curve for sentinel node biopsy in breast cancer: practical considerations.

HYPOTHESIS: Performance of sentinel node biopsy (SNB) instead of full axillary lymph node dissection (ALND) by inexperienced surgeons will lead to understaging of some women with breast cancer and increased costs. DESIGN: A decision analysis model was used to investigate the implications of SNB vs. full ALND during the learning phase (60-80 procedures). This model simulates a randomized trial of 10000 women in each arm. Data regarding the learning curve were obtained from published series. MAIN OUTCOME MEASURES: Percentage of women with inaccurate staging of their breast cancer, overall survival, quality-adjusted survival, and potential costs of SNB vs ALND. RESULTS: Performance of SNB instead of ALND results in inability to locate a sentinel node in 38% of attempts during the learning phase (compared with 10% in later cases) and understaging in 12% of patients during the learning phase (compared with 0% in later cases). This understaging is associated with a small decrement in survival (1%-2%) and an increased risk of axillary recurrence. Sentinel node biopsy is cost-effective only when the ability to detect sentinel nodes exceeds 80%; and the cost of SNB is less than 50% of the cost of ALND. CONCLUSIONS: To ensure accurate staging of patients with breast cancer, all surgeons should perform full ALND while learning SNB techniques. Only after documentation of accuracy of SNB (sensitivity >90%) should full ALND be omitted for women with negative sentinel nodes.

Biopsy↗

PubMed1999

A learning curve for laparoscopic splenectomy at an academic institution.

BACKGROUND: Laparoscopic splenectomy is emerging as the standard for treatment of benign splenic disorders. Since splenectomy is indicated relatively infrequently, issues arise concerning training of surgeons to perform laparoscopic splenectomy. Our experience with 50 laparoscopic splenic procedures is reported with emphasis on the learning curve at an academic institution. MATERIALS AND METHODS: Data were prospectively collected on 50 consecutive patients undergoing attempted or successful laparoscopic surgical procedures on the spleen at Northwestern Memorial Hospital or The Chicago Health Care System, Lakeside Division, from April 1993 to April 1998, and on 5 patients undergoing open splenectomy from April 1993 to October 1995. Outcomes including conversion rate, operative time, day feedings were tolerated, and length of hospital stay was examined and correlated with the number of attempted cases. RESULTS: Laparoscopic splenectomy progressed from an operation requiring two advanced laparoscopic surgeons to one performed by carefully supervised senior residents. Success rates increased from 60% initially to greater than 95% recently. Likewise, operative time decreased significantly from 195 to 97 min, while length of stay declined from 2.5 to 1.5 days. High success rates, low operative times, and short length of stays were achieved during the last 20 patients while surgical residents were taught to perform the procedures. The reasons for improvement are multifactorial including use of the harmonic scalpel, a change to the lateral position, and increasing experience with the procedure. CONCLUSIONS: Laparoscopic splenectomy is a safe and effective procedure that reduces postoperative length of hospital stay. It can be performed successfully in most patients with operative times comparable to those of open splenectomy. Moreover, the procedure can (and should) be taught to residents once they master basic and advanced laparoscopic skills.

Adult↗

PubMed1991

Competency and the colonoscopist: a learning curve.

The first 334 consecutive unassisted studies of a trainee colonoscopist were audited to analyse the relationship between experience and a target 90% completion rate of colonoscopy. The cumulative sum (cusum) score was applied to examine the time trend for the attaining of the target 90% completion rate. This technique described a learning curve which showed, in this instance, that approximately 100 studies were necessary before a 90% completion rate was approached. A further 100 studies were required before this target completion rate was achieved consistently. A trend for continued improvement above the 90% completion rate level was also seen after 200 studies. Polypectomy was completed in 117 of the 123 studies where indicated. Cusum analysis may be a useful method for monitoring the progress of the trainee colonoscopist and the attainment of satisfactory competence. Training requirements, therefore, might better emphasize the attainment of an acceptable completion rate rather than an arbitrary quota per se.

Clinical Competence↗

PubMedDate not supplied

[The effect of the learning curve and the experience on the technique and the outcome of laparoscopic treatment for gastroesophageal reflux].

The laparoscopic treatment for gastroesophageal reflux disease (GERD) 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, and failures are assumed to be greater. The aim of this study was to compare the results of laparoscopic treatment for GR in 3 groups of consecutive patients in order to determine the effect of the learning period and the experience on the technique and the outcome. One hundred and fifty patients (84 men and 66 women) with an average age of 52.2 years (18 to 78) were included. Surgery was indicated for failure or early relapse following the end of medical treatment. The preoperative work-up (endoscopy, barium meal or oesophageal 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 50 patients around were chronologically defined. The parameters that were examined were: the operative technique; the conversion rate; the mortality and morbidity rate; 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 GERD. All patients had an endoscopy, 91% a barium meal, 77.5% underwent esophageal manometry and 67% pH monitoring. One hundred and thirty two patients had a TF and 18 had a PF. Rosetti's type TF became the reference procedure (80.3% in group III) and closure of the diaphragmatic crura was performed systematically in group III (100%). The duration of surgery was significantly reduced between group I and the two other groups (138, 100, 80 mn.). The rate of conversion, due to a variety of causes, decreased from 10.2% to 4% and then 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 14.3% to 4% and then 0%. There was 7 cases of relapse (4.6%), 5 in group 1 (10.2%) and 2 in group II (4%), with no cases in group III although the follow-up is 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 in order to allow a more accurate comparison of the different treatments for GERD.

Adolescent↗

PubMed1995

Continuing hazards of the learning curve in laparoscopic cholecystectomy.

Bile duct injury is one of the most serious complications of laparoscopic cholecystectomy (LC). In open cholecystectomy (OC) the reported incidence of injury is less than 0.2 per cent. In LC, the aggregate reported experience, in many thousands of cases, is three or four times this number. Although "the learning curve" has been considered the principal factor in the heightened incidence of this complication with LC, there are hazards inherent in this new surgical modality that may never allow elimination of the increased risk of bile duct injury. As a sequel to an earlier report of 1200 cases of OC before the laparoscopic era from a single institution, this report deals with the next 2427 consecutive cases of LC from the same institution. In the first 1284 cases of LC, there were seven bile duct injuries (0.58%); in the ensuing 1143 cases there were six bile duct injuries (0.50%). The overall incidence nationwide is even higher, as evidenced by widespread reports of repair of bile duct injuries referred to major tertiary care centers. Routine operative cholangiography is of the utmost importance in the early recognition and immediate repair of ductal injuries. In 12 of the 13 cases reported here, early recognition and repair during the primary surgery resulted in a successful outcome.

Bile Ducts↗

PubMed1997

Submitting your manuscript on disk: a steep learning curve for authors and editors.

Many nursing journals are switching to state-of-the-art manuscript production systems. Most of these new systems include computerized typesetting, so some journals are requesting disk submission of manuscripts. However, computer disk submission is not without difficulties. Editors and authors alike are experiencing a fairly steep learning curve before developing a system where the author's disk can work in the publisher's production system. This article describes how authors and editors can collaborate on the disk submission system for nursing publications.

Algorithms↗

PubMed2006

The effect of learning curve on the outcome of caesarean section.

OBJECTIVE: To evaluate the operative outcomes when trainees first perform caesarean sections independently. DESIGN: A retrospective study in a tertiary obstetric unit. POPULATION: Five hundred caesarean sections, which represented the first 50 caesarean sections performed independently by each of ten trainees, were studied. METHODS: The effect of learning curve on outcome was analysed. MAIN OUTCOME MEASURES: Total operative time, incision-to-delivery interval, operative blood loss, Apgar score, cord arterial pH, incidence of neonatal intensive care unit admission, postoperative complication rates and duration of hospitalisation. RESULTS: The mean operative time for the first five cases by trainees was 52.2 +/- 11.4 minutes. It progressively decreased and reached 39.6 +/- 8.4 minutes for the 46th to 50th cases. The operative time was significantly longer in the first 15 caesarean sections (P < 0.05). Moreover, the incision-to-delivery interval was also longer during the first five cases (P= 0.02). Besides the time of the operation, the trend for operative blood loss stabilised after the first ten caesarean sections (P < 0.05). Otherwise, there were no significant differences among other outcome variables. CONCLUSION: This study shows that trainees need to perform 10-15 caesarean sections before their skills become more proficient. Senior obstetricians may need to provide guidance to the trainees during their first independent 15 caesarean sections.

Apgar Score↗

PubMed2002

Contrast agents provide a faster learning curve in dipyridamole stress echocardiography.

AIM: Interobserver variability is an important limitation of the stress echocardiography and depends on the echocardiographer training. Our aim was to evaluate if the use of contrast agents during dipyridamole stress echocardiography would improve the agreement between an experienced and a non-experienced observer in stress echo and therefore if contrast would affect the learning period of dypyridamole stress echo. METHODS AND RESULTS: Two independent observers without knowledge of any patient data interpreted all stress studies. One observer was an experienced one and the other had experience in echocardiography but not in stress echo. Two observers analysed 87 non-selected and consecutive studies. Out of the 87 studies, 46 were performed without contrast administration, whereas i.v. contrast (2.5 g Levovist by two bolus at rest and at peak stress) was administered in 41. In all cases, second harmonic imaging and stress digitalisation pack was used. The agreement between observers showed a kappa index of 0.58 and 0.83 without and with contrast administration, respectively. CONCLUSIONS: The use of contrast agents provides a better agreement in the evaluation of stress echo between an experienced and a non-experienced observer in stress echo. Adding routinely contrast agents could probably reduce the number of exams required for the necessary learning curve in stress echocardiography.

Clinical Competence↗

PubMed1991

The learning curve in stapes surgery.

Fewer stapes operations are available to train residents and to maintain individual competence. Most residents in the United States perform 0 to 10 cases during training, and produce results which are not as good as expert results, even with close supervision. After graduation, fewer cases are available to achieve expert results in private or academic practice. The authors' conclusions and recommendations are based on his own learning curve. Residents who have below average skills in middle ear surgery, and residents who do not wish to practice otology, should watch but not perform stapes surgery. Program directors, collectively or separately, should develop more formal guidelines for teaching stapes surgery during residency.

Clinical Competence↗

PubMed2006

Learning curves and reliability measures for virtual reality simulation in the performance assessment of carotid angiography.

OBJECTIVES: Improvement in performance as measured by metric-based procedural errors must be demonstrated if virtual reality (VR) simulation is to be used as a valid means of proficiency assessment and improvement in procedural-based medical skills. BACKGROUND: The Food and Drug Administration requires completion of VR simulation training for physicians learning to perform carotid stenting. METHODS: Interventional cardiologists (n = 20) participating in the Emory NeuroAnatomy Carotid Training program underwent an instructional course on carotid angiography and then performed five serial simulated carotid angiograms on the Vascular Interventional System Trainer (VIST) VR simulator (Mentice AB, Gothenburg, Sweden). Of the subjects, 90% completed the full assessment. Procedure time (PT), fluoroscopy time (FT), contrast volume, and composite catheter handling errors (CE) were recorded by the simulator. RESULTS: An improvement was noted in PT, contrast volume, FT, and CE when comparing the subjects' first and last simulations (all p < 0.05). The internal consistency of the VIST VR simulator as assessed with standardized coefficient alpha was high (range 0.81 to 0.93), except for FT (alpha = 0.36). Test-retest reliability was high for CE (r = 0.9, p = 0.0001). CONCLUSIONS: A learning curve with improved performance was demonstrated on the VIST simulator. This study represents the largest collection of such data to date in carotid VR simulation and is the first report to establish the internal consistency of the VIST simulator and its test-retest reliability across several metrics. These metrics are fundamental benchmarks in the validation of any measurement device. Composite catheter handling errors represent measurable dynamic metrics with high test-retest reliability that are required for the high-stakes assessment of procedural skills.

Cardiology↗

PubMed2005

Acquiring proficiency in off-pump surgery: traversing the learning curve, reproducibility, and quality control.

As the risk profile of patients considered for surgical revascularization worsens, the cumulative benefit of off-pump coronary artery bypass (OPCAB) over conventional coronary artery bypass grafting, in terms of lower morbidity and reduced healthcare costs, may increase. There is still resistance to the introduction of OPCAB surgery however, its practice is variable and surgical residents are rarely trained in these techniques. This article considers how the learning curve in OPCAB may be negotiated and prospectively monitored to ensure quality control. The evidence suggests that situations in which suitable senior expertise exists, OPCAB surgery can be introduced into surgical practice and safely taught to trainees without detriment to patients. This is achieved by a progressive increase in the complexity of the case mix and careful early supervision. The introduction of OPCAB has coincided with the increasing use of control charts as quality control tools. Performance monitoring provides reassurance that patients are not being put at risk during the introduction of OPCAB; control chart methods can be used prospectively for real time performance monitoring by consultant surgeons and residents alike. These techniques may ultimately be used to determine proficiency and accreditation. Increasing use of parallel training techniques, the development of structured training programs that encompass OPCAB and other new technologies in cardiac surgery, coupled with objective performance monitoring are warranted to meet the needs of a changing patient population.

Clinical Competence↗

PubMed2006

Learning curve in human laparoscopic surgery.

Laparoscopic urology has gained considerable popularity since the first laparoscopic nephrectomy was performed. However, the rapid application of the technique in urologic practice has led to increased reports of complications, even in the hands of surgeons who are well experienced in open surgical techniques, often early in a surgeon's laparoscopic experience. The lack of translation of open surgical skills into laparoscopic results has led us to reappraise the learning curves relevant to open and laparoscopic surgery, to understand the differences, and enable us to make changes in the curriculum and the training to acquire laparoscopic skills.

Clinical Competence↗

PubMed2001

Learning curve for translaryngeal tracheotomy in head and neck surgery.

OBJECTIVES: Translaryngeal tracheotomy (TLT) is a widely accepted procedure in intensive-care units for its simplicity of execution, low morbidity, rapid wound closure after cannula removal, good esthetic results, and lack of long-term sequelae. The aim of this study was to evaluate the feasibility and use of adopting TLT in patients with cancer undergoing major head and neck surgery. STUDY DESIGN: Prospective analysis of learning curve and incidence of complications in 41 patients with cancer who underwent TLT at the Division of Head and Neck Surgery of the European Institute of Oncology from November 1997 to June 1999. METHODS: Patient characteristics, pathology, anatomic characteristics of the neck, and surgical short-term and long-term complications were noted. The patients were divided into consecutive groups of six or seven patients, and time trends in occurrence of complications and time to execute the procedure were assessed. RESULTS: TLT performance time decreased from 50 minutes in the first seven patients to 24 minutes in the last group. The technique was easy to perform and safe, with only two minor complications during surgery. However, minor complications occurred in three and major complications in 17 patients in the days immediately following surgery, almost entirely attributable to lack of counter-cannula and stylet. CONCLUSIONS: In view of the high proportion of major complications, TLT using the presently available kit is unsuitable for major head and neck surgery. However, the considerable advantages of the technique would recommend it as a valid alternative to surgical tracheotomy if the kit included a counter-cannula and stylet.

Clinical Competence↗

PubMed1998

Lasik learning curve: clinical study of 300 myopic eyes.

We present a retrospective analysis of the short term results of our first 300 myopic eyes which have been corrected by LASIK refractive surgery using the Automated corneal shaper and the NIDEK EC 5000 excimer. We will discuss our technique and outcome based on the evaluation of the safety of the procedure and the predictability of the postoperative result. We discuss all the complications we have encountered during this learning curve.

Astigmatism↗

PubMed1992

The learning curve for intraoperative echocardiography during congenital heart surgery.

Our group has previously reported a large prospective experience with the use of intraoperative echocardiography with Doppler color-flow imaging (IE-DCFI) during the repair of congenital heart defects. We have now performed IE-DCFI in 621 patients and have observed a major change in the impact of this technology, which has stabilized during our most recent experience (the last 207 patients). To evaluate the surgical learning curve with IE-DCFI, we divided patients into three groups: group 1, patients 1 through 207; group 2, patients 208 through 414; and group 3, patients 415 through 621. There were no major differences between groups with respect to age or disease entities. The average time needed to perform an IE-DCFI examination decreased from 3.75 +/- 1.77 minutes in group 1 to 3.35 +/- 1.52 minutes in group 2 and has remained stable. The number of patients requiring revisions in the operating room (based on IE-DCFI findings) decreased from 17 (8%) in group 1 to 7 (3%) in group 2 to 5 (2%) in group 3. Furthermore, revisions were 100% successful in correcting the problem in groups 2 and 3, whereas 18% of group 1 patients left the operating room with persistent residual defects by IE-DCFI. Surgeons can acquire the ability to interpret the results of IE-DCFI themselves and use it to enhance their operative repair of congenital heart defects, but this requires an experience of at least 200 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Surgical Procedures↗

PubMed2002

Evidence for direct learning curve for technique on change of cervical sampling device.

The recommended sampling device within the NHS Cervical Screening Programme is the Aylesbury spatula. A local decision was taken to decrease brush usage (either alone or in combination) by 50% from an initial level of 41.8%, with an initial inadequate smear rate of 9.93%. This was managed by controlling smear taking equipment through provision of smear taking kits. The monthly inadequate rate unexpectedly rose to 17.8% before dropping back to previous levels. Brush usage overall fell to 35.2%, with a corresponding increase in spatula use. The possible reasons for this are discussed. The facts suggest that these changes were directly linked, and that there is a learning curve with change of sampling device and that a rise in the inadequate rate should be expected under these circumstances.

Female↗