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PubMed1995

Evaluation and the learning curve of the first one hundred laparoscopic hysterectomies.

BACKGROUND: We analyzed the first one hundred laparoscopic hysterectomies done by one senior gynecologist to study the learning curve and complications of this technique. METHODS: One hundred laparoscopic hysterectomies done for uterine fibroid (64%), menorrhagia (20%), adenomyosis or endometriosis (10%), cervical dysplasia (3%) and endometrial cancer (3%) were studied. RESULTS: No conversion to laparotomy was needed. The weight of the uterus ranged from 70 to 470 grams (mean 206 g) and the operating time ranged from 45 to 245 minutes (mean 109 min). The mean operating time was reduced from 180 to 75 minutes. The uterine weight and the weight of the patient had a positive correlation to operating time. The use of automatic staplers or clips did not reduce the operating time. Ten complications occurred: one perforation of the urinary bladder, five bleedings and four pelvic infections. CONCLUSION: The operating time was clearly shortened during the first one hundred laparoscopic hysterectomies. The rate of the complications did not fall similarly. Technical complications (bladder perforation and intraoperative bleeding) occurred in the beginning. Complications like infection and bleeding do not seem to disappear with experience. Laparoscopic hysterectomy appears to be as safe as abdominal or vaginal hysterectomy and the postoperative convalescence time is short. It is clearly an acceptable alternative to hysterectomy.

Adult↗
PubMed1995

The learning curve for radiofrequency ablation of tachyarrhythmias in pediatric patients. Participating members of the Pediatric Electrophysiology Society.

The results of radiofrequency ablation for treatment of supraventricular tachyarrhythmias have been reported to improve with increasing experience; however, the precise nature of the learning curve in children is unknown. From November 1990 to October 1993, 1,546 consecutive procedures from the Pediatric Radiofrequency Ablation Registry were categorized into deciles based on number of prior pediatric procedures at the submitting institution. Negative exponential models were tested for strength of relation between volume of prior experience and 4 measures of outcome: success rate, complication rate, fluoroscopy time, and procedure time. Negative exponential curves described the experience-outcome relations well (r = 0.81 to 0.97). Learning rates were most rapid for successful ablation of left free wall accessory pathways, and slowest for right free wall pathway ablation. These models suggest that, given enough experience, procedural success rates > 90% (regardless of pathway location) and fluoroscopy and procedure times averaging < 40 minutes and 250 minutes, respectively, can be achieved in pediatric patients.

Adolescent↗
PubMed2006

[Learning curve of laparoscopic resection for rectal cancer].

OBJECTIVE: To evaluate the surgical outcomes of laparoscopic resection for rectal cancer and to investigate how surgeons without previous training of laparoscopic cholecystectomy(LC) can quickly learn laparoscopic resection for rectal cancer. METHODS: Clinical data of 105 cases of laparoscopic rectal resection performed by a group of surgeons without previous training of LC were reviewed. The cases were divided equally into 3 groups (groups A, B and C) according to the sequence of the operations. The operating time, blood loss, lymph node harvest, length of specimen, conversion rate to open surgery, intra- and postoperative complications and hospital stay were compared between the 3 groups. RESULTS: There were no significant differences between the 3 groups with respect to age, gender, Dukes'stage or surgical approach (P>0.05). The operating time in group A was 196.1+/-30.3 min, significantly longer than that in group B (164.8+/-22.7 min) and group C (158.7+/-20.9 min) (P<0.001), but the operating time did not vary significantly between groups B and C (P>0.05). The blood loss was significantly greater in group A than in groups B and C (72.4+/-21.5, 48.2+/-16.3, and 46.6+/-15.4 ml, respectively, P<0.001), but showed no significant difference between the latter two groups (P>0.05). The rate of conversion to open surgery decreased from 11.4% in group A to 2.9% in group B and group C, but the difference was not statistically significant (P>0.05). The rate of intraoperative complications declined from 17.1% in group A to 5.7% in group B and group C, showing no significant difference either. The lymph node harvest, length of specimen, and postoperative complications showed no significant variation between the 3 groups (P>0.05), but group C had significantly shorter mean hospital stay in comparison with groups A and B (P<0.001). The 35 patients in group A received the operation within a time period of 17 months (2.1 cases per month), and operations in groups B and C were done in 7 months (5 cases per month). CONCLUSION: The learning curve of laparoscopic rectal resections is approximately 35 cases, and the surgeons without previous experience of laparoscopic cholecystectomy can learn the surgical skills after performing 35 laparoscopic resections for rectal cancer at the monthly frequency of 2.1 cases.

Adult↗
PubMed1996

Experience during the learning curve of laser in situ keratomileusis.

PURPOSE: To identify pitfalls and offer hints on achieving a successful outcome during the early laser in situ keratomileusis (LASIK) learning process. SETTING: Gimbel Eye Centre, Calgary, Alberta, Canada. METHODS: This was a retrospective review of the preoperative planning, surgical procedure, intraoperative and postoperative problems, and early postoperative anatomic and refractive results in the first 73 eyes that had LASIK. RESULTS: Intraoperative complications included failure of the keratome to make a cut, excessively thin cap, repositioning difficulty, and inadequate intraocular pressure elevation. Early postoperative complications included excessive central and peripheral wrinkling of the cap, peripheral lipid deposits, and central edema of the cap. One month postoperatively, mean spherical equivalent refraction was -0.90 diopters (D) (range +1.75 to -6.00 D), and 45 eyes had a best corrected visual acuity between 20/15 and 20/40. CONCLUSION: Our retrospective review of the problems experienced during the early LASIK learning process should help novice lamellar refractive surgeons avoid such problems and shorten the learning curve.

Adult↗
PubMed2003

Robotic surgery: identifying the learning curve through objective measurement of skill.

BACKGROUND: The incorporation of new devices into surgical practice often requires that surgeons acquire and master new skills. We studied the learning curve for intracorporeal knot tying in robotic surgery. METHODS: We developed an objective scoring system to evaluate knot tying and tested eight attending surgeons during 3 weeks of training on a surgical robot. Each performed intracorporeal knot tying tasks both before and after robotic skills training. These performances were compared to their laparoscopic knots and analyzed to determine and define skill improvement. RESULTS: Baseline laparoscopic knot completion took 140 sec (range, 47-432), with a mean composite score of 77 (100 possible), whereas robotic knot tying took 390 sec, with a mean composite score of 40. After initial robotic training, times decreased by 65% to 139 sec and scores increased to 71. With more training, completion times and composite scores were improved and errors were reduced. CONCLUSION: Like any new technology, surgical robotics requires dedicated training to achieve mastery. Initially, even experienced laparoscopists may register an inferior performance. However, after adequate training, surgeons can exceed their laparoscopic performance, completing intracorporeal knots better and faster using robotics.

Adult↗
PubMed1999

Cost and quality trends under managed care: is there a learning curve in behavioral health carve-out plans?

The paper studies the performance of network plans over time using data from 52 managed behavioral health plans. Costs exhibit a 'learning curve' with additional cost declines of 10-15% with every doubling of experience, which are independent from time trends and scale economies. Process-of-care measures show increased appropriateness of follow-up care and reduced 30-day rehospitalization, but the relationship to experience or time is not statistically significant. Possible causes of organizational 'learning' could be faster referrals to network clinicians, increased acceptance of network providers by patients, selection of more efficient providers, improved care management procedures, or better monitoring techniques.

Behavioral Medicine↗
PubMed2006

Why the Kantian ideal survives medical learning curves, and why it matters.

The "Kantian ideal" is often misunderstood as invoking individual autonomy rather than rational self legislation. Le Morvan and Stock's otherwise insightful discussion of "Medical learning curves and the Kantian ideal"--for example--draws the mistaken inference that that ideal is inconsistent with the realities of medical practice. But it is not. Rationally to be a patient entails accepting its necessary conditions.

Attitude to Health↗
PubMed2005

Laparoscopic extraperitoneal radical prostatectomy--learning curve of a laparoscopy-naive urologist in a community hospital.

OBJECTIVES: To describe the training approach that a laparoscopy-naive general urologist working in a nonteaching hospital used to successfully learn to perform laparoscopic extraperitoneal radical prostatectomy and describe the results obtained in the first 114 cases performed. METHODS: The urologist assisted an experienced laparoscopic surgeon for 20 extraperitoneal radical prostatectomies. During this time, he modified his technique of performing open radical retropubic prostatectomy to facilitate the acquisition of the laparoscopic techniques. Intracorporeal suturing was learned with the aid of a pelvic trainer. The clinical records of the first consecutive 114 cases were examined to evaluate the outcomes in terms of morbidity and oncological and functional concerns. A similar analysis was performed on a subgroup of 15 patients who had undergone laparoscopic extraperitoneal radical prostatectomy after previous transurethral resection of the prostate. RESULTS: The operating time progressively decreased during the learning curve. The mean duration of surgery was 160 minutes. Two conversions to open surgery were required owing to failure to progress. Of the 114 patients, 14% experienced complications, most of which were minor. The positive surgical margin rate was 17%. The average follow-up was 16 months. Undetectable serum prostate-specific antigen levels were observed in 82%, 87%, and 79% at 6, 12, and 18 months, respectively; 96% of patients used 0 to 1 pad per day for incontinence at 6 months of follow-up. The results in the transurethral resection subgroup were similar. CONCLUSIONS: Laparoscopic extraperitoneal radical prostatectomy can be successfully learned by a general urologist with no prior laparoscopic experience.

Adult↗
PubMed2001

Laparoscopic intracorporeal ultrasound versus fluoroscopic intraoperative cholangiography: after the learning curve.

BACKGROUND: The purpose of this study was to compare the results of laparoscopic intracorporeal ultrasound (LICU) to those of fluoroscopic intraoperative cholangiography (FIOC) during laparoscopic cholecystectomy (LC) after the initial learning curve for LICU. METHODS: Data were prospectively collected on patients undergoing LC. A consecutive series of 394 LICU patients was compared to a consecutive series of 400 FIOC patients when each imaging procedure was preferentially performed. Patients during the transition period, including the first 100 LICU patients, were excluded. RESULTS: Demographics and preoperative diagnoses were similar in the two groups. Excluding those who were converted to open cholecystectomy and those in whom an imaging exam was not attempted, FIOC was successful in 361 of 374 (97%) patients and LICU was successful in 377 of 380 (99%) patients (p < 0.03). The mean times (+/-SEM) to complete FIOC and LICU were 16.0 (+/-0.5) min and 5.1 (+/-0.1) min (p < 0.0001), respectively, Choledocholithiasis was detected in 25 patients (7%) undergoing FIOC and in 39 patients (10%) undergoing LICU (p = 0.1). During LICU the common bile duct was visualized in continuity from the cystic duct to ampulla in 90% of cases. The common bile duct could not be completely visualized in continuity at the middle or distal portion of the common bile duct in 5% and 6% of LICU cases, respectively. One LICU patient (0.3%) with an incompletely visualized duct had a suspected stone confirmed by postoperative endoscopic retrograde cholangiopancreaticography (ERCP). One patient with negative FIOC (0.3%) had a retained stone treated by postoperative ERCP. CONCLUSION: LICU is safe and accurate, and it permits a more rapid evaluation of bile duct stones than FIOC during laparoscopic cholecystectomy. The false-negative rate of both imaging techniques is less than 1%.

Cholangiography↗
PubMed2002

The learning curve of selective salpingography and tubal catheterization.

OBJECTIVE: To determine the effect of increasing experience in fluoroscopically guided selective salpingography and tubal catheterization on radiation doses and screening times, thus establishing a learning curve for the procedure. DESIGN: Retrospective case note analysis. SETTING: IVF center of an academic teaching hospital. PATIENTS: Three hundred sixty-six patients with infertility seen over 3.5 years. INTERVENTION(S): Fluoroscopically guided selective salpingography and tubal catheterization. MAIN OUTCOME MEASURE(S): Reductions in radiation doses and screening times for different categories of selective salpingography and tubal catheterization, expressed as percentage reductions during the study period and reductions per 10 procedures. RESULT(S): During the study period, The median dose of radiation decreased by 62.6%-71.9%, and the median screening time declined by 61.5%-78.5%. Reductions per 10 procedures were 2.5%-4.2% and 2.7%-5%, respectively. CONCLUSION(S): Significant reductions in radiation doses and screening times start early in a clinical team's practice of selective salpingography and tubal catheterization and continue even as trainees are added to the pool of operators.

Catheterization↗
PubMed1998

Laparoscopic biliary injury: more than a learning curve problem.

BACKGROUND: The increase in the incidence of iatrogenic injury to the extrahepatic biliary tree that has been documented since the introduction of laparoscopic cholecystectomy (LC) has been explained as a 'learning curve' problem. The early New Zealand experience has been published and the present study was undertaken to determine whether there had been any change in the incidence, nature and management of laparoscopic biliary injuries (LBI) after further experience with LC. METHODS: A nationwide audit was undertaken in 1995 by two confidential postal questionnaires: to all active general surgeons (n=184, response rate 60%), and to all endoscopists performing endoscopic retrograde cholangiopancreatography (ERCP) (n=18, response rate 100%). RESULTS: The total number of LBI was 21, compared with 41 for 1991-92. The site and nature of the injuries were similar for the two survey periods. More of the injuries appeared to be diagnosed after the operation and prior to discharge (25% vs 47%). Calculating the national incidence of LBI was not possible without complete reporting, but in the subset of surgeons responsible for the LBI there was no apparent decrease in the incidence of all LBI (2.8% vs 2.9%), those requiring active re-intervention (2.4% vs 2.7%) and major duct injury (1.1% vs 0.7%), despite a significant increase in the surgeons' prior experience with LC (20% vs 61% of surgeons had performed more than 100 LC). There were some concerning trends in management: a less frequent use of ERCP in patients with LBI diagnosed after surgery (76% vs 65%) and a higher proportion of patients with minor injuries managed by re-operation (26% vs 50%). CONCLUSIONS: The present study indicates that iatrogenic biliary injury is a persistent problem in New Zealand, despite increasing experience with LC, and suggests the need for more intensive scrutiny of operative technique and training. There is scope to manage more patients with minor duct injuries conservatively.

Bile Ducts, Extrahepatic↗
PubMed1999

Treating previable twin-twin transfusion syndrome with fetoscopic laser surgery: outcomes following the learning curve.

AIMS: We have performed fetoscopic laser occlusion of chorioangiopagous vessels (FLOC) in previable pregnancies affected by twin-twin transfusion syndrome (TTTS) since 1988. Treatment outcomes obtained after the procedure's learning curve are presented and compared to those from other centers performing FLOC or other treatment methods. METHODS: A total of 100 cases of FLOC have been performed at our centers. The later 67 TTTS patients had a mean gestational age of 21.1 +/- 1.7 weeks (range 18-24.5) with a mean fundal height of 33.1 +/- 4.9 cm (range 27-44) when treated. Eighteen (27%) had failed another treatment method before FLOC. RESULTS: All 67 cases have delivered with 82% (55/67) having at least one surviving twin and 93/134 (69%) of the twins surviving overall. Thirty-eight have surviving twins, 17 have one survivor (5 neonatal and 12 fetal deaths), and 12 have none. The mean duration of pregnancy following FLOC was 9.9 +/- 5.5 weeks (range 1.0-19). Only 4 of 93 (4.3%) survivors have significant handicaps at a mean follow-up of 14.3 +/- 10.1 months (range 1.0-34). CONCLUSION: Fetoscopic laser occlusion of chorioangiopagous vessels within the vascular equator limits the duration of fetal pathophysiology in TTTS and results in neonatal outcomes superior to the modified procedure and other treatment methods.

Diseases in Twins↗
PubMed1985

[Percutaneous nephrostolithotomy. Technic and learning curve].

The closed controlled manipulation of the urinary tract (endourology) has provided rapid advances in urologic therapy. Various methods are available for percutaneous stone removal. After 300 p.c. nephrostolithotomies we present the 'learning curve' leading to our technique of endourologic stone manipulation.

Humans↗
PubMed2001

Evaluation of 142 consecutive laparoscopic fundoplications in children: effects of the learning curve and technical choice.

PURPOSE: This retrospective study describes the 5-year experience of a single surgeon with 142 consecutive laparoscopic fundoplications in children and analyzes the results in terms of the surgeon's learning curve and the choice of technique. METHODS: The patients were 44 girls (40%) and 98 boys (60%) with an age range of 3 months to 18 years (mean, 5.35 years). Indications for surgery included medically refractory reflux associated with vomiting, pneumopathy, otorhinolaryngologic pathology, failure to thrive, esophagitis, apnea and bradycardia, or anemia. The laparoscopic surgery used 5 trocars of 5 mm or 3 mm, with a 30 degrees telescope. RESULTS: Laparoscopic fundoplication was successful in 139 cases. The authors performed 13 Nissen techniques without short gastric vessel division (SGVD), 47 Toupets without SGVD, 9 Toupets with SGVD, and 70 Nissens with SGVD. Mean operating time was 105 minutes (range, 45 to 300). Mean time was 125 minutes for the first 60 cases and 93 minutes for the other 79 cases). Intraoperative and postoperative complication rates were 0.5% and 2%, respectively, and the complications occurred in the first 60 cases. Mean postoperative hospital stay was 3 days (range, 2 to 14). CONCLUSIONS: The rate of complication caused by the laparoscopic procedure was acceptable, and it decreased with the surgeon's experience. Complications and conversions to open technique occurred only in the beginning of the operator's experience. Dysphagia, epigastric pain, gas bloating, and early reflux recurrences were noted among the first 60 cases but seemed to be consecutive to the fact that the gastric vessels were not divided. J Pediatr Surg 36:921-926.

Adolescent↗
PubMed2005

Arthroscopic rotator cuff repair: the learning curve.

PURPOSE: The purpose of this study was to answer the question: How many cases are required for a surgeon to become proficient in performing arthroscopic rotator cuff repair? We hypothesize that as surgical experienced is gained, learning can be quantitatively shown by a significant decrease in operative time. TYPE OF STUDY: Prospective case series. METHODS: Rotator cuff repair time (RCRT) in minutes (as well as other time components comprising total surgical time) was recorded for 100 consecutive patients having arthroscopic rotator cuff repair performed by a single surgeon beginning with his first case in private practice. Mean RCRTs for consecutive blocks of 10 cases were compared. Learning is graphically represented by plotting the RCRT by case number and generating a logarithmic trend curve. A best-fit linear equation (y = mx + b) allows comparison of the initial 10 cases with the subsequent 90 cases, where m , the slope, represents the rate of decrease in RCRT (learning). RESULTS: Mean RCRT decreased significantly (P < .05) from the first block of 10 cases to the second block of 10 cases. There were no significant changes in mean RCRT when comparing other consecutive blocks of 10 cases. The slope of the line fitting the first block of 10 cases is -8.75; the slope (m) of the line fitting the subsequent 90 cases is -0.23. There is no significant difference in mean RCRT when cases are stratified by tear size. CONCLUSIONS: Graphic representation of RCRT by case number generates a learning curve whereby learning is quantitatively shown as a significant decrease in operative time as surgical experience is gained. CLINICAL RELEVANCE: Qualification of the learning curve for arthroscopic rotator cuff repair provides a guide for orthopaedic surgeons contemplating the expected time line for acquiring proficiency in this technique.

Arthroscopy↗
PubMed2002

Learning curve of video-assisted thoracoscopic esophagectomy and extensive lymphadenectomy for squamous cell cancer of the thoracic esophagus and results.

BACKGROUND: The efficacy of thoracoscopic radical esophagectomy for cancer of the thoracic esophagus and the learning curve required have yet to be clearly established. METHODS: Eighty treatment-naive patients with esophageal cancer without contiguous spread underwent esophageal mobilization and extensive mediastinal lymphadenectomy through a 5-cm minithoracotomy and four trocar ports. The outcomes in the first 34 patients (group 1) and the last 46 patients (group 2) were compared. RESULTS: There were no differences in background or clinicopathologic factors between the two groups. The duration of the thoracoscopic procedure and blood loss were less (p <0.0001), the incidence of postoperative pulmonary infection was less (p = 0.0127), and the number of mediastinal nodes retrieved was greater (p = 0.0076) in group 2. Multivariate analysis demonstrated that surgical experience (number of cases performed) predicted the risk of pulmonary infection (p = 0.0331). CONCLUSION: Video-assisted thoracoscopic radical esophagectomy can be performed with safety and efficacy comparable to those of open esophagectomy. Morbidity decreases with the surgeon's experience.

Adult↗