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At least 541 records · Page 30Linked to original sources
PubMed1994

Examination of the early 'learning curve' for transcatheter closure of patent ductus arteriosus using the Rashkind occluder. PDA Closure Comparative Study Group.

BACKGROUND: Results of transcatheter implantation of the Rashkind double umbrella occluder for treatment of patent ductus arteriosus (PDA) have improved over time. We evaluated factors associated with changes in outcomes seen in the early clinical experience with this device. METHODS AND RESULTS: We reviewed records of otherwise healthy pediatric patients undergoing occluder implantation for isolated PDA between 1982 and 1987 at six major US and Canadian referral centers. Logistic regression was used to assess the impact of ductal size, patient age and weight, calendar time, prior intrainstitutional occluder experience, and residual center effects on closure rates. There were no study deaths. Of 180 occluder placement attempts, 76.7% (95% confidence limits = 70.5%, 83.0%) produced PDA closure by auscultation at 14-month cardiology follow-up or its equivalent. Success probabilities increased in a linear fashion as ductus size decreased, ranging from 41.7% for large (4.1 to 9.0-mm) ducts to 89.4% for small (1.5 to 2.5-mm) lesions. PDA occluder closure rates also improved over time, increasing from 47.4% in 1982-1983 to 84.6% in 1986 and 83.1% in 1987. Multivariate logistic regression indicated that improved outcomes were mainly attributable to decrease in the size of treated ducts over time. Independent of this patient selection, improvements in outcome were less strongly associated with cumulative intracenter experience, calendar time, and age. CONCLUSIONS: Increasing closure rates seen over time primarily reflected more judicious selection of patients as experience accumulated. However, other factors also contributed to the observed trends. An analysis of current treatment results would be of considerable interest.

Age Factors↗
PubMed1994

The learning curve.

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Cholecystectomy, Laparoscopic↗
PubMed1996

Laparoscopic surgery for gastro-oesophageal reflux: beyond the learning curve.

From September 1991 to October 1995, 320 Nissen fundoplications were undertaken laparoscopically by 12 surgeons at a single institution. To assess the performance of the procedure in the hands of five 'experienced' surgeons, the first 20 procedures performed by each surgeon or surgical trainee were excluded, providing a group of 174 patients for review. A short loose 360 degrees fundoplication was performed in all instances, with short gastric vessel division performed in 35.0 per cent of patients and hiatal repair in 66.7 per cent. Median operating time was 80 (range 30-210) min and median postoperative stay was 3 (range 1-19) days. Sixteen procedures (9.2 per cent) could not be completed laparoscopically and required conversion to open surgery. Some 144 patients were reviewed by a scientific officer 3 months after surgery, 85 at 12 months, and 32 at 2 years, using a standard clinical questionnaire. All but one were free from reflux symptoms, although 20.1 per cent reported some dysphagia at 3 months' follow-up; this figure declined to 11 per cent at 12 months and 6 per cent (two of 34 patients) at 2 years. At each follow-up interval, 91 per cent of patients were satisfied with the outcome of the surgery. Objective testing with oesophageal motility (75 patients) and barium swallow (113) studies 3-6 months after surgery confirmed the clinical outcome. Complications occurred in nine patients (5.2 per cent); four (2.3 per cent) of these required a subsequent operation within 30 days of surgery for bleeding (one patient), paraoesophageal herniation (one) and dysphagia (two). A further procedure was necessary in six other patients (3.4 per cent) for late problems, including paraoesophageal herniation (two), hiatal stenosis (three) and gastric obstruction (one). Revision was performed laparoscopically in two patients. The clinical results of laparoscopic Nissen fundoplication by 'experienced' laparoscopic surgeons were comparable with those of open surgery.

Adolescent↗
PubMedDate not supplied

Learning curve.

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Education, Nursing, Continuing↗
PubMed1998

Learning curve and conversion to open surgery in cases of laparoscopic adrenalectomy and nephrectomy.

PURPOSE: We examine how the level of experience acquired by the laparoscopist affects the outcome of laparoscopic adrenalectomy and nephrectomy, and what is necessary to avoid complications in these surgeries. MATERIALS AND METHODS: We retrospectively evaluated the experience levels of 8 urological laparoscopists between 1991 and 1995. In addition, other cases that were converted to open surgery were collected from the institutes with which the 8 laparoscopists were affiliated. RESULTS: The rates of conversion to open surgery were 6.4% in 204 cases of adrenalectomy and 14.3% in 63 of nephrectomy. Conversion rates were related to blood loss volume but not operative time. The major causes of conversion were bleeding in 45% of cases and adhesion in 34%. There were no mortalities. Mean operative time decreased significantly, reaching that of open surgery as the number of procedures increased up to 20 adrenalectomies and 10 nephrectomies. The volume of blood lost remained low from the early experience. Blood transfusion rates were 4.4% for adrenalectomy and 11.1% for nephrectomy. CONCLUSIONS: Operative time of these procedures decreased significantly with surgeon experience and reached that of open surgery. Cases in which adhesion is anticipated should be restricted to avoid conversion. These laparoscopic procedures are acceptable as a standard operative techniques for adrenal and renal diseases.

Adrenal Gland Diseases↗
PubMed1998

[The learning curve in refractive laser surgery: criteria for outcome evaluation].

BACKGROUND: We wanted to analyse and compare the results of our first 100 cases of refractive surgery using the commonly accepted refractive parameters and using more subjective data. MATERIALS AND METHODS: Retrospective analysis of the first 100 consecutive cases of refractive surgery using objective and subjective criteria. RESULTS: Our objective refractive results are comparable to the results of many other authors. The subjective evaluation reveals a large discrepancy compared to the objective data. CONCLUSIONS: The evaluation of the results in refractive surgery should include more subjective parameters. This will allow to better correlate the quality-parameters of the surgery to the patient's expectations.

Adult↗