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PubMed2005

Robotic radical prostatectomy in the community setting--the learning curve and beyond: initial 200 cases.

PURPOSE: The introduction of robotic assistance has the potential to improve surgical outcomes and reduce the steep learning curve associated with conventional laparoscopic radical prostatectomy. We report on our experience with robotic radical prostatectomy in the community setting. MATERIALS AND METHODS: A total of 200 patients underwent robotic radical prostatectomy during 18 months. Prospective data collection included a quality of life (Expanded Prostate Cancer Index Composite) questionnaire, basic demographics, prostate specific antigen (PSA), clinical stage and Gleason grade. Operative outcome measures included operative time, estimated blood loss and complications. Postoperative outcome measures included hospital stay, catheter time, pathology, PSA and return of continence. RESULTS: Average operative time was 141 minutes with an estimated blood loss of 75 cc. The intraoperative complication rate was 1% with no mortality, reexploration or transfusion. Of the patients 95% were discharged home on postoperative day 1 (1 to 3) with hematocrit averaging 34.5 (range 25 to 45). The average difference in preoperative and postoperative hematocrit was 3 points (range -2 to 15). Average catheter time was 7.2 days (range 5 to 15). The positive margin rate was 10.5% for the entire series, 5.7% for T2 tumors, 28.5% (T3a), 20% (T3b) and 33% (T4a). Of the patients 95% had undetectable PSA (less than 0.1 ng/ml) at average followup of 9.7 months. Continence at 1, 3, 6, 9 and 12 months was 47%, 78%, 89%, 92% and 98%, respectively. CONCLUSIONS: Our initial experience with robotic radical prostatectomy is promising. The learning curve was approximately 20 to 25 cases. With a structured methodical approach we were able to implement robotics safely and effectively into our community practice with minimal patient morbidity, and good oncological and functional outcomes.

Adult↗
PubMedDate not supplied

The learning curve of an academic cardiac surgeon: use of the CUSUM method.

BACKGROUND: Despite the sizeable volume of research on the determinants of outcome after cardiac operations, few articles have analyzed the learning curves of individual cardiac surgeons over time. The objective of our study was to analyze statistically the learning curve of an academic cardiac surgeon in reducing operative morbidity and mortality during a 10-year interval. METHODS: The study cohort of 1347 consecutive and unselected patients undergoing cardiac surgical operations from October 1988 to September 1998 were grouped into five 2-year blocks (periods 1 to 5) according to the date of operation. The main outcome measures were operative mortality rate and standardized definitions of perioperative myocardial infarction, intra-aortic balloon pump use, reoperation for bleeding, stroke, sternal wound complications, sepsis, and respiratory insufficiency. Preoperative risk factors and operative results in periods 1 to 5 were compared statistically using a chi-square test for linear trend (categorical variables) or analysis of variance with linear contrast and lack of fit tests (continuous variables). In addition, the cumulative sum (CUSUM) method was used to determine the association among operative morbidity, mortality, and prespecified 80% alert and 95% alarm boundary lines in practice years 1, 5, and 9. RESULTS: Of the preoperative risk factors, only patient age showed an important change during the 10 years of the study (61.3+/-0.7 to 64.3+/-0.6, p = 0.001). There were no statistically significant changes from periods 1 to 5 in overall operative mortality (4.0% to 2.2%, p = 0.56) or in the rates of perioperative stroke (1.8% to 3.8%, p = 0.33), sternal wound complications (0.4% to 0.8%, p = 0.97), sepsis (0.9% to 0.8%, p = 0.63), or respiratory failure (4.4% to 2.8%, p = 0.21). Decreases occurred in a linear fashion during periods 1 to 5 in mortality after coronary artery bypass grafting (5.1% to 1.3%, p = 0.012) and in the rates of perioperative myocardial infarction (7.0% to 2.2%, p = 0.005), intra-aortic balloon pump use (7.0% to 3.0%, p = 0.05), and reoperation for bleeding (8.4% to 2.2%, p = 0.001). The number of uneventful cases between a death or complication increased from 2.82+/-0.43 in period 1 to 6.44+/-1.10 in period 5 (p < 0.001). On CUSUM analysis, the cumulative failure rate in year 1 transgressed the upper 80% alert line after 56 cases and the upper 95% alarm line after 69 cases. During years 5 and 9 the failure rate gravitated around the 80% and 95% "reassurance" lines, respectively, indicating improved results as compared to year 1. CONCLUSIONS: The mortality rate after coronary artery bypass grafting and select perioperative morbidity rates improved in a linear fashion from the onset of independent practice to year 10. The CUSUM method was helpful in identifying suboptimal results during the first year of practice and shows promise as a method of prospective quality control in cardiac surgery. These data support mentorship of new consultants by a senior surgeon during the first year or two of independent practice.

Adult↗
PubMed2005

Laparoscopic colorectal surgery: learning curve and training implications.

AIMS: This paper is a review of experience of laparoscopic colorectal surgery at a district general hospital with particular emphasis on the learning curve and training implications. METHODS: All patients undergoing colorectal surgery where laparoscopy was attempted between March 1998 and October 2003 were included in this study. RESULTS: There were 80 patients of which 49 had malignancy. Twenty eight stomas and 52 bowel resections were performed laparoscopically. The conversion rate for bowel resection was 32% (decreasing from 38% to 44% to 22%). This was significant (p = 0.001) when compared with stoma formation (7%). The firm has support from a specialist registrar and staff grade surgeon. In 22% of cases, one of the middle grades was the principal operating surgeon, mainly laparoscopic mobilisation and stoma formation. Only 6% of resections were performed by the middle grades. Conversely, a middle grade was the main operating surgeon in 66% of open resections and 61% of stoma formations during the same period. There were in all two deaths and 14 postoperative complications. All patients who had laparoscopic resections for malignancy had clear resection margins. CONCLUSION: This audit highlights that there is a long learning curve in laparoscopic colorectal surgery with decrease in conversion rates with increasing experience. There is also a reduction in training opportunities in open surgery during the learning phase of the consultant, although this may be counterbalanced by the exposure to laparoscopic techniques. Laparoscopic colonic mobilisation, as a part of stoma formation, is a good starting point for specialist registrar training.

Adult↗
PubMed2002

The effect of robotic assistance on learning curves for basic laparoscopic skills.

BACKGROUND: We hypothesized that laparoscopic tasks performed with ZEUS robotic assistance would be done with greater precision and with a different learning curve than when performed in a standard laparoscopic trainer. METHODS: Participants were divided into the surgically experienced (n = 11) and the surgically naive (n = 17). Two laparoscopic tasks (bead transfer and rope pass) were repeated for five repetitions. RESULTS: For all drills and participants, completion time and error rate decreased across the five repetitions for each platform. Precision averaged 97% for both platforms over all drills. For both groups, completion time for tasks was shorter on the laparoscopic platform. ZEUS allowed for greater consistency in performance. CONCLUSIONS: Compared with performance on a standard laparoscopic trainer, robotic assistance allows for increasing speed and consistency while maintaining precision over multiple repetitions. Understanding how robotics affects learning curves will allow for modifications in the training experience with this new technology.

Adult↗
PubMed2006

Complications and the learning curve for a laparoscopic nephrectomy at a single institution.

BACKGROUND: We assessed our experiences in performing a laparoscopic nephrectomy, with regard to complications and the learning curve, during a 4-year period. METHODS: Between November 2000 and October 2004, a total of 78 laparoscopic nephrectomies were performed at our institution (37 radical nephrectomies, 30 nephroureterectomies and 11 simple nephrectomies). The patient charts were retrospectively reviewed to identify any operative and postoperative complications, and also to evaluate the operating time. RESULTS: A total of eleven complications (14.1%) occurred in our series (nine operative and two postoperative complications). All operative complications were due to vascular injuries (n=9), five (2.6%) of which required an open conversion. The operating time and the rates of complications decreased significantly as the surgeons' experiences increased. CONCLUSION: A laparoscopic nephrectomy could be performed as safely as previously reported. In addition, the learning curve for a laparoscopic nephrectomy appeared to be good over the initial 50 procedures at our institution.

Humans↗
PubMed2002

Laparoscopic Roux-en-Y gastric bypass: defining the learning curve.

BACKGROUND: Increasing numbers of laparoscopic surgeons are performing laparoscopic Roux-en-Y gastric bypass (LGB). Our aim was to determine the length of the learning curve for a skilled laparoscopic surgeon. METHODS: The study population consisted of the first 225 consecutive LGB procedures attempted by one laparoscopic surgeon (HJS). Outcome parameters included mortality, morbidity, operative time, and conversion to an open procedure. RESULTS: Average operative time decreased from 189 min (first 75 patients) to 125 minutes (last 75 patients). Most of the improvement in operative time occurred over the first 75 patients. The perioperative complication rate decreased from 32% (first 75 patients) to 15% (second and third groups of 75 patients). Complication rates did not significantly decrease after the first 75 patients. Low mortality and conversion rates were achieved early in the series. CONCLUSION: Low mortality rates and low conversion rates can be achieved early in the learning curve for LGB. Complication rates plateau after approximately 75 LGBs, and operative times decrease substantially over the initial 75 cases. Operative times continue to decrease at a slower rate beyond 75 cases.

Adult↗
PubMedDate not supplied

The learning curve associated with a simulated ultrasound-guided interventional task by inexperienced anesthesia residents.

BACKGROUND AND OBJECTIVE: Ultrasound has become an increasingly popular modality in facilitating the performance of peripheral nerve blocks. There exists no literature that examines the learning curve of the ultrasound novice. In this prospective series, we evaluated the learning curve of inexperienced anesthesia residents in performing a simulated ultrasound-guided interventional procedure. In doing so, we hoped to identify reproducible patterns of human errors, which could potentially aid in the prevention of real-life iatrogenic injuries. METHODS: Ten subjects were prospectively enrolled. After a brief introduction to the ultrasound system, the subjects were asked to perform 6 sequential trials of a simulated breast cyst aspiration. For the first 3 trials, each subject attempted to place a 22-gauge b-bevel needle into any aspect of an olive buried inside the turkey breast. After completion of these 3 trials, the subjects were asked to place the needle into the exact midpoint of the olive wall closest to the transducer. Trials were videotaped and analyzed for task performance in terms of speed and accuracy. RESULTS: All subjects successfully completed the 6 interventional trials. The mean time to perform the task was reduced by 38% and 48%, respectively, for the second and third trials. A composite score of accuracy showed an improvement of 36% and 59%, respectively, for the second and third trials. The most common committed error, which occurred in 7 of 10 subjects, was the failure to accurately image the needle while advancing. This resulted in excessive depth of penetration and inadvertent transfixation of the olive in 5 of these subjects. CONCLUSIONS: Anesthesiology residents, with little or no ultrasound experience, can rapidly learn and improve their speed and accuracy in performing a simulated interventional ultrasound procedure. A concerning novice pattern was identified where the subjects advanced the needle even though it was not appropriately visualized in the ultrasound beam. This resulted in needle placement error, which could cause iatrogenic injury in the clinical setting.

Adult↗
PubMed2006

[A study of 4,031 patients of transurethral resection of the prostate performed by one surgeon: learning curve, surgical results and postoperative complications].

A total of 4,031 patients who underwent transurethral resection of the prostate (TURP) performed by one surgeon between May 1979 and December 2003 were retrospectively examined to determine the improvement of the surgeon's skill in performing TURP assessed by using a learning curve, surgical results and postoperative complications. Analysis using the learning curve, which displayed the relationship between the number of TURP procedures and the speed of resection (i.e., the weight of tissue resected divided by the operation time), revealed that 81 operations were needed before the surgeon's skill reached a plateau in performing TURP. The means +/- standard deviations of the weight of tissue resected, operation time and speed of resection were 17.0 +/- 14.6 g, 21.0 +/- 13.5 minutes, 0.80 +/- 0.32 g/minutes, respectively. As the number of TURP procedures increased and the level of skill improved, the operation time was significantly reduced and the speed of resection was significantly increased. The incidences of postoperative complications were 2.4% for blood transfusion, 0.3% for the TURP syndrome, 1.5% for hemostatic procedures, 2.8% for bladder neck contracture, and 1.0% for urethral stricture. The incidences of transfusion and the TURP syndrome decreased as the surgeon's skill improved. The mortality rate was 0.1%.

Aged↗
PubMed1995

Femorotibial bypass: the learning curve.

Femorotibial bypass is still infrequently performed in many district hospitals, because it is time consuming and the risk of failure is high, especially during the learning curve. This article reviews the results of a single consultant surgeon and his team after starting femorotibial bypass de novo in a district general hospital. During the period 1987 to 1992, 85 femorotibial grafts were performed in 76 patients for ulceration and gangrene (57), rest pain (19) and severe claudication (9). Sixty-six were autogenous vein, 15 were PTFE with distal vein cuff, two were composites and two were umbilical vein. Overall, 22 grafts (26%) failed within the first 30 days (two were salvaged) and 21 amputations were required (five despite patent grafts). There were three early deaths (mortality 3.9%). At the end of 1993, 39 limbs had been amputated and 24 patients had died (eight with amputations). Twenty-three (44% of survivors) were alive with patent grafts. These disappointing early results were due to an initial technical learning curve, after which increased confidence may have led to reconstructing some patients with inadequate distal arteries. A more selective approach is now used. Limb salvage can be achieved in a worthwhile proportion of these patients and 3-year primary patency rates are similar to those of teaching hospitals in this country.

Aged↗
PubMed2002

[Prospective assessment of the learning curve and safety of stapler hemorrhoidectomy].

INTRODUCTION: Stapled haemorrhoidectomy (SH) is a recently introduced procedure for the surgical excision of haemorrhoids. Actually, there is only limited information concerning the impact of the learning curve, complication rates and long-term results. Therefore, a prospective single-center study was performed with special regard to the learning curve and clinical safety of SH. METHODS: The data of 61 SH performed between March 1999 and May 2001 were analyzed. Operating times, complication rates and outcome results were prospectively recorded and then correlated to the surgical experience of the operating team. Postoperative pain was measured using the visual analogue scale (VAS). Sphincter lesions represented by the patient's incontinence and muscle defects were analyzed by using Williams incontinence score and histological examination of the resected specimen. Clinical follow-up studies were performed three and twelve weeks postoperatively. RESULTS: There were 18 patients with grade II haemorrhoids, 38 patients with grade III haemorrhoids, and five patients with grade IV haemorrhoids. Both, operating times and complication rates decreased with more surgical experience. The mean pain score during the first four postoperative days was 1.9 (range 0-8). Mean hospital stay and mean convalescence time were 1.7 days (range 1-5 days) and 10 days (range 1-31 days), respectively. Incontinence scores revealed only minor differences between pre- and postoperative values. CONCLUSIONS: SH represents a safe and effective new treatment modality for symptomatic haemorrhoids. Meticulous surgical technique and experience are mandatory to achieve excellent clinical results, e.g., reduced postoperative pain, shortened hospital stay and convalescence. We adopted SH to our surgical armamentarium for the treatment of haemorrhoids grade III and recurrent haemorrhoids.

Adolescent↗
PubMed2006

The learning curve for hand-assisted laparoscopic colectomy: a single surgeon's experience.

BACKGROUND: Surgical experience and outcomes for hand-assisted laparoscopic colectomy were evaluated to define a learning curve. METHODS: This study included 60 patients who underwent hand-assisted laparoscopic colectomies performed by a single surgeon. They were analyzed as three consecutive equal groups: A, B, and C. Pearson's chi-square test and one-way analysis of variance (ANOVA) were used to compare differences in demographics and perioperative parameters. Operative times were analyzed to document the learning curve for the procedure. RESULTS: There were no significant differences between the three groups in terms of age, sex, operative procedure, or comorbidity. Groups B and C showed significantly shorter operative times, significantly earlier recoveries of gastrointestinal function, less blood loss, and shorter hospital stays than group A. The incidence of operative complications was not significantly different among the three groups (35% vs 5% vs 15%; p = 0.07). CONCLUSIONS: Approximately 21 to 25 cases were needed to achieve proficiency in this series.

Adult↗
PubMed2000

Learning curve of microvascular venous anastomosis: a never ending struggle?

In this study, a simple protocol based on the rat femoral venous anastomosis was established to provide a quantitative representation of the progress. The learning curve is based on the patency rate in each consecutive group of five anastomoses. Two groups of surgeons were observed. The inexperienced group encountered a tough time in the first 25 anastomoses. However, the progress was fast and is represented by the steep slope of the curve. A plateau was reached whereby the avearge patency rate matches that of the experienced group. As expected, there was no learning curve for the experienced group. Despite every effort to attempt to maintain a perfect 100% patency on this model, the best achievable patency was only 88%. The results and its implication are discussed.

Anastomosis, Surgical↗
PubMed1997

Impact of the learning curve on term delivery rates following laparoscopic salpingostomy for infertility associated with distal tubal occlusive disease.

The objective of this study was to determine the impact of the learning curve of one surgeon on the term delivery rate following laparoscopic salpingostomy for tubal infertility. This was a retrospective audit of ongoing clinical practice, undertaken in two tertiary level infertility programmes. Subjects in this study were women undergoing surgery for total occlusion of the distal Fallopian tube. The main outcome measure was cumulative term delivery rates. On stepwise life-table analysis the length of infertility, primary and secondary infertility, tubal diameter and whether surgery was performed in the first or second half of the series were significantly associated with outcome. These data suggest that there is a learning curve in obtaining skills to perform laparoscopic salpingostomy, that patient selection may improve with experience, and that selection criteria should be emphasized during didactic teaching and the preceptorship process.

Adult↗
PubMed2001

The learning curve associated with pediatric laparoscopic splenectomy.

BACKGROUND: Laparoscopic splenectomy (LS) is technically difficult compared with open splenectomy. This report examines our experience with LS to define the learning curve. METHODS: The first 49 consecutive laparoscopic splenectomies were reviewed. Indications, complications, operative time, and costs were recorded. RESULTS: Indications included hereditary spherocytosis, immune thrombocytopenia purpura, beta-thalassemia, lymphoma, splenic cysts, and abscesses. Surgical time averaged 196 minutes for the first 10 patients, decreasing to 105 minutes for the last 10. Blood loss for the first 10 patients averaged 50 cc and less than 5 cc for the last 10. There were 3 complications and 1 conversion to open operation. Operative and hospital charges averaged $6,670 and $13,402, respectively, for the first 10 cases compared with $5,278 and $10,863 for the last 10. CONCLUSIONS: LS can be performed safely with few complications. LS has a steep learning curve in the first 20 patients after which operative times decrease along with overall costs.

Child↗
PubMed2003

Laparoscopic adjustable gastric banding: is there a learning curve?

BACKGROUND: To be certified for laparoscopic placement of adjustable gastric banding, surgeons must have advanced laparoscopic experience. Despite previous exposure to other kinds of laparoscopy, there may a learning curve specific to Lap-Band placement. METHODS: Sixty consecutive patients were prospectively separated into two groups: the first 30 patients operated on (group 1) and the second 30 patients operated on (group 2). RESULTS: Both groups were similar statistically in regard to gender, age, and body mass index. Operative time for group 1 was 79 +/- 31.1 min. There were 11 (37%) complications in 10 patients. Operative time for group 2 was 59 +/- 19.9 min. There were two complications (7%). All operations were completed laparoscopically. Operative time was significantly lower in group 2 ( t-test; p = 004). Complications were also significantly lower (chi-square; p = 0.005). The number of reoperations was also reduced and approached statistical significance (chi-square; p = 0.054). Readmissions, although reduced, were not statistically significant. There were no deaths in either group. CONCLUSIONS: Despite a surgeon's history of advanced laparoscopic experience, there is a definite learning curve associated with the laparoscopically placed adjustable gastric band.

Adult↗
PubMed2004

Qualitative and quantitative analysis of the learning curve of a simulated surgical task on the da Vinci system.

BACKGROUND: Robotic telemanipulation systems provide solutions to the problems of less dexterity and visual constraints of minimally invasive surgery (MIS). However, their influence over surgeons' dexterity and learning curve needs to be assessed. We present motion analysis as an objective method to measure performance and learning progress.METHODS. Thirteen surgeons completed five synthetic small bowel anastomoses using the da Vinci system. Objective Structured Assessment of Technical Skills (OSATS) allowed qualitative analysis. Quantitative analysis used API software of the system to retrieve real-time robotic signal data of time, path length, and number of movements. Wilcoxon signed ranks test was used for statistical analysis. A p value <0.05 was considered significant.RESULTS. OSATS global scores were 18.6 points for the first attempt and 26 for the fifth attempt ( p < 0.02, Cronbach's alpha = 0.894). Paired data of motion analysis for attempts 1 vs 5 showed significant change: time taken 3507 sec and 2287 sec ( p < 0.008), total number of movements 2411 and 1387 ( p = 0.01), total path length 21,630 cm and 13,941 cm ( p = 0.01).CONCLUSIONS. A rapid learning curve to a competent level using the da Vinci system is possible aided by the system's intuitive motion. Motion analysis is a useful tool to measure performance in the da Vinci system compared to OSATS and time alone.

Anastomosis, Surgical↗
PubMed1994

The learning curve for laparoscopic cholecystectomy.

The introduction of laparoscopic cholecystectomy (LC) in 1987 has resulted in its wide acceptance by surgeons in the United States. Questions about proper training and learning curve for surgeons wishing to perform laparoscopic procedures have been raised during this period. We retrospectively evaluated 416 consecutive cholecystectomy cases that were performed by eight surgeons in a community teaching hospital. In this report, 374 patients had LC and 42 patients (10%) had an attempted LC, which had to be converted to an open cholecystectomy (CONV). Surgeons A and B performed 40% and 18% of all LC cases, respectively, and were classified as the surgeons with the highest volume of cases. Parameters, including conversion rate, operative time, and complications, were evaluated to define the learning curve. Surgeons A and B experienced 17% and 14% initial conversion rates for the first 35 cases, respectively. These rates dramatically dropped to an acceptable level (4% and 3%) with increased experience. The operative time for surgeon A for the first and last 35 cases improved from 97 +/- 25 min to 74 +/- 32 min (p = 0.01). Although the procedure time for surgeon B improved by 4 min, this difference was not statistically significant. The operative time for all cases was 81 +/- 31 min and 87 +/- 27 min, respectively, for surgeons A and B, which was significantly less than that for other surgeons (p = 0.01). A total of 12 patients experienced complications related to LC. Most of the complications (75%) occurred in the first 30 cases for all surgeons.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗