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PubMed2006

Short-, intermediate-, and long-term quality of life after laparoscopic radical prostatectomy--does the learning curve of LRP have a negative impact on patients' quality of life?

OBJECTIVES: To evaluate quality of life (QoL) after laparoscopic radical prostatectomy (LRP) and investigate whether the learning curve of laparoscopic novices has a negative influence on patients' QoL. METHODS: Evaluation of QoL with the EORTC QLQ C-30 and the PR25 preoperatively (t0) as well as postoperatively after 1-3 mo (t1), 4-6 mo (t2), 7-12 mo (t3), 13-24 mo (t4), and yearly thereafter (t5-t7). Surgeons were grouped according to their prior experience in laparoscopy into experienced and novices. RESULTS: LRP was performed in 343 patients; 268 (78%) participated in the study. The mean patient age was 63.3+/-6.3 yr; mean PSA, 10.0+/-9.2 ng/ml; mean follow-up, 26 mo. Global health was impaired for t1 (p<0.001) and then returned to baseline. Emotional functioning improved (p<0.001) for t2-t7 versus baseline. Physical functioning remained impaired for t1-t2, and role and social functioning for t1-t6. Only sexual functioning did not return to baseline for t1-t7. Urinary symptoms were worse at t1 and then improved gradually (p<0.001). No significant difference in any QoL domain could be identified for experienced surgeons versus novices except for financial difficulties at t2-t3, which related to social differences. Thirty-one (9%) patients with adjuvant therapy had significantly worse global health, bowel symptoms, urinary symptoms, fatigue, and sexual functioning. CONCLUSIONS: The learning curve of laparoscopic novices does not have a negative impact on patients' QoL. For intermediate- to long-term follow-up, patients reach their baseline or score even better in all domains except for sexual functioning but are significantly impaired if adjuvant treatment is performed.

Clinical Competence↗

PubMedDate not supplied

[Learning curve and his consequences in laparoscopic antireflux surgery].

The laparoscopic fundoplication became the gold standard of the laparoscopic antireflux surgery (LARS). Our aim is to indicate the evolution of the learning curve as well as its consequences on the patient's outcome. We studied the gastro-esophageal reflux (GER) cases treated laparoscopically in Colţea University Hospital throughout 6 years. We gathered a group of 40 patients with an average age of 54, 57 years and a sex ratio F:M = 1.67. The patients had either a simple GER disease, small and medium hiatal hernias (21 cases) or giant hiatal hernias (GHH--19 cases). Two equal groups resulted: group 1 consisted of the first 20 patients operated from 1999 to 2002, group 2 consisted of the rest of the patients. Operating time, hospital time, complication rate and postoperatory endoscopy were compared. The average of the operating time was calculated. For giant hiatal hernias, a separate average was also taken into account. The total operating time for GER, small and medium hiatal hernias was 115 min in group 1 and 80 min in group 2 meanwhile for GHH it was 143 min vs. 130 min. The average operatory time was 129 min vs. 105 min. All these differences were statistically significant but there were no differences concerning complication rate and post-operatory endoscopy. Although the learning of the laparoscopic fundoplication requires practice, the learning curve does not have influence on the patients' outcome.

Adult↗

PubMed2002

The learning curve for sentinel node biopsy in malignant melanoma.

Sentinel node biopsy (SNB) has emerged as an accurate means of identifying nodal micrometastasis in cutaneous melanoma. In order to assess our learning curve, we compared our first 30 cases with our subsequent 30 cases. A total of 60 patients underwent SNB for cutaneous melanoma, using preoperative lymphoscintigraphy together with the intraoperative use of a Neoprobe and Patent Blue V dye. At least one sentinel node was identified in 93% of patients (90% in our first 30 cases; 97% in our subsequent 30 cases). Sentinel nodes contained tumour in 21% of cases. Of the sentinel nodes that contained tumour in the first 30 cases, 87% were identified by Neoprobe examination and 60% using blue dye. In the second 30 cases, the tumour-containing sentinel nodes were identified in all cases by both the Neoprobe and the blue dye. The sentinel node appeared to be the only involved node in 71% of patients. In the first 30 patients, one patient with a negative sentinel node developed nodal recurrence. These data confirm the feasibility of the sentinel-node technique in cutaneous melanoma. However, there is a learning curve, and the technique should be performed only by limited numbers of people with suitable training.

Clinical Competence↗

PubMedDate not supplied

[Laparoscopic colorectal surgery: is the "learning curve" necessary?].

AIM OF THE STUDY: To present the early experience of the Authors' division in the field of colorectal laparoscopic surgery, in order to evaluate the so-called "learning curve". MATERIALS AND METHOD: From February 2003 to May 2004, we have performed 220 surgical procedures for colorectal pathology: 63 were conducted by a laparoscopic approach with 10 patients who, converted to a laparotomic procedure in theatre, were not taken under consideration. The present work is thus based on a population of 53 patients, 27 men and 26 women, at a median age of 64.4 y.o. (range 42-81). RESULTS: We performed 1 total colectomy, 24 right hemicolectomy, 1 resection of the splenic flexure, 12 left hemicolectomy (in 1 case a left hepatic lobectomy was associated), 11 anterior resection of the rectum, 1 Hartmann' sigmoid resection and 3 abdomino-perineal resection. Mean operative time was 200.34 +/- 64.17 min, while the mean hospital stay was 6.44 +/- 2.68 days. Peri-operative mortality was 0%, 30-days mortality was 1/53 patients (9%) while morbidity was 5/53 patients (9.4%): in 2 cases reintervention was necessary. DISCUSSION: From the evaluation of the results, we found some significant data: first, the conversion rate was similar to those reported by other authors, so also the mortality and morbidity rates. CONCLUSIONS: The advantages of the laparoscopic technique, indirectly documented by shorter in-hospital stay. At least for patients submitted to right or left hemicolectomy without complications (5.5 e 5.7 days, respectively), could be seen also after only a 1 year of activity. As far as the "learning curve" is concerned, dividing our activity into 3 times, we verified a progressive shortening of the operative time and, at least for the patients submitted to a right emicolecomy, also of the morbidity rates.

Adult↗

PubMed1996

[Individual learning curves with reference to endonasal micro-endoscopic pan-sinus operation].

BACKGROUND: We examined how surgeons in training will develop into experienced surgeons in sinus surgery by analysing their individual learning curve. METHODS: In a retrospective study we evaluated complications in 818 surgical procedures (362 revisions = 44.3%) performed by four different surgeons. RESULTS: We found a dural lesion in six cases (0.75%), opening of the periosteum of the orbit in 30 cases (3.7%), and control of bleeding from the anterior ethmoidal artery in 36 cases (4.4%). No lesions of the internal carotid artery or lacrimal duct system occurred. The complications were not distributed equally. We observed a three-phase learning process which we describe using the example of a traffic light: red with a high risk of complications, yellow with a minor one, and green for the experienced surgeon. The first phase consists of the first 20 procedures, yellow from the 20th to the 100th, and green for procedures performed thereafter. CONCLUSIONS: Each inexperienced surgeon has to determine his position on the learning curve. He or she should be supervised accordingly.

Clinical Competence↗

PubMed2000

The learning curve of laparoscopic cholecystectomy and changes in indications: one institutions's experience with 2,650 cholecystectomies.

PURPOSE: In a prospective series of 2,650 consecutive patients undergoing cholecystectomy, we analyzed the learning curve since the introduction of laparoscopic cholecystectomy (LC) in terms of operating time, conversion rate, morbidity, mortality, and consequent changes in indications for either laparoscopic or open cholecystectomy (OC). PATIENTS AND METHODS: Between July 1990 and June 1997, LC was performed in 1,929 patients (73%), 203 of whom (7.5%) had to be converted to OC, while 518 patients (19.5%) had primary OC. Patients having LC were predominantly female, younger, with less comorbidity and less complicated gallstone disease than patients having OC. RESULTS: Barring a learning curve during the first 6 months of LC, operating time remained constant at an average of 71 minutes while operating on ever more complex pathologies. The conversion rate decreased from 9.4% to 6.7% during the 7-year period. A relatively constant team of surgeons with growing experience as well as constantly improving technical equipment allowed the complication rate to remain low. The total morbidity of LC was 2.5% (0.1% bile duct injury), that of conversions 5%, and that of OC 12.5%. The mortality was 0 for LC, 0.5% for conversions, and 1% for OC. CONCLUSION: The indications for primary OC decreased from 50% to 8.5% and the indications for LC could be broadened over the years.

Cholecystectomy↗

PubMed1994

Phacoemulsification--a senior surgeon's learning curve.

We sought to prospectively document and evaluate the learning curve of an experienced extracapsular surgeon making a supervised transition from extracapsular cataract extraction (ECCE) to phacoemulsification. Over a period of 2 weeks, 51 phacoemulsification procedures using an endocapsular nucleofractis technique were performed by a single senior surgeon at the Christian Medical College in Vellore, India under the supervision of a visiting US expert with more than 15 years' experience in the technique. Vitreous loss occurred in seven eyes (six prior to the stage of cortical aspiration); failure of capsulorhexis necessitated conversion to standard ECCE in four. Injury to the inferior iris during phacoemulsification was cosmetically significant in three eyes. Two eyes had mild persistent localized corneal edema, but there were no instances of permanent corneal damage. One eye had intraoperative displacement of the nucleus into the vitreous. In one eye with vitreous loss, the implanted intraocular lens dislocated into the vitreous cavity. Two patients had clinically detectable cystoid macular edema at 6 weeks. Eleven patients were lost to follow up after 3 weeks. Six weeks after surgery, 36 of the remaining 40 eyes (90%) had achieved a best-corrected visual acuity of 6/6. We conclude that phacoemulsification requires supervised learning, even for an experienced surgeon. Complications still occurred, but were restricted to the unfamiliar steps of the surgery. Factors identified in the first 2 days of surgery (10 cases) as critical in the smooth transition to phacoemulsification were careful selection of initial cases, a successful capsulorhexis, and hydrodissection with vigorous nucleus mobilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Astigmatism↗

PubMed2002

Learning curve for unilateral endoscopic totally extraperitoneal (TEP) inguinal hernioplasty.

BACKGROUND: Performance of endoscopic totally extraperitoneal inguinal hernioplasty (TEP) requires specialized anatomical knowledge and surgical dexterity. The present study was undertaken to evaluate the learning curve for a general surgeon to master the technique of TEP in the absence of an experienced supervisor. METHODS: A retrospective analysis of the first 120 consecutive unilateral TEPs was performed. Medical records were reviewed to evaluate demographic features, perioperative outcome, and follow-up results. The study population was divided into six consecutive groups of 20 patients. Clinical data were compared among the groups to evaluate the impact of operative experience on perioperative outcome. RESULTS: Operative time was the only clinical parameter that showed significant improvement with experience; it reached a plateau value of <1 h after the fourth group. Conversions to transabdominal and open approaches were required in only one patient in groups 1 and 6, respectively. Comparison of demographic features, hernia types, postoperative morbidity rates, length of hospital stay, and number of days to resume normal activities showed no significant differences among the groups. All complications were minor and resolved uneventfully. No recurrence was detected during follow-up. CONCLUSIONS: The learning curve for unilateral TEP by a general surgeon peaked after performing 80 procedures. In most cases, unilateral TEP can be accomplished safely within 1 h. Even during the learning process, TEP carries a low morbidity and conversion rate.

Adult↗

PubMed1998

Radial keratotomy learning curve using the American technique.

PURPOSE: To delineate the learning curve for a beginning refractive surgeon using the centrifugal (American) technique. SETTING: Naval Medical Center, San Diego, California, USA. METHODS: The first 100 radial keratotomy (RK) cases (51 patients) of one surgeon, divided into five sequential groups of 20, were retrospectively reviewed. All patients had RK using the American technique. Emmetropia was the goal in all patients. Groups were compared with respect to preoperative refractive status, age, sex, and outcome. Outcomes analysis included visual acuity, refractive error, complications, and enhancement rates. Data were reviewed preoperatively and 1 and 3 months postoperatively. RESULTS: All five groups were age and sex matched. There was no difference in preoperative refractive error among the five groups. Sequential improvement in early postoperative refractive error from a mean of -1.73 diopters (D) +/- 1.00 (SD) (first 20) to 0.45 +/- 0.55 D (last 20) (P < .001) and decreased enhancement rates from 50% (first 20) to 0% (last 20) (P = .002) were statistically significant. Visual acuity at 1 month was 20/40 or better in 47% of patients in Group 1 (first 20), whereas all patients in Group 5 (last 20) had an acuity better than 20/40 (P < .001). There was no significant difference in complication rates among the five groups. CONCLUSION: The results of RK using the American technique can improve significantly with surgeon experience. Enhancement rates decreased with experience, and there was no difference in complication rates during the learning period of one surgeon.

Adult↗

PubMed2000

The learning curve in prostate seed implantation.

OBJECTIVE: To describe the learning curve in prostate seed implantation, according to the experience with two groups of 100 patients. MATERIAL AND METHODS: A perineal, ultrasound-guided implantation technique with manual afterloading was used in all patients. Of a total of 255 patients treated over the period 1989 through 1998, the results of the first hundred patients were compared in relation to the last hundred patients. In the first group single seeds were used, while in the second group RAPID Strands were applied. RESULTS: Although there is a difference in the follow-up period, a significant difference is found in disease-free survival between the two groups. PSA progression was noticed in 39% of patients in the first group and in 12% in the other group. The strongest prognostic factor, however, is the initial PSA value. Toxicity is relatively low, though higher in the second group. CONCLUSIONS: The results obtained in the second hundred patients are in agreement with data from literature. Differences in outcome between the two groups are, however, not only explained by differences in technique, but also by selection and total number of implanted seeds.

Aged↗

PubMed1998

[Transesophageal echocardiography for diagnosis of traumatic injuries to the major intrathoracic vessels in 150 patients: the effect of the learning curve].

OBJECTIVES: To evaluate the role of transoesophageal echocardiography (TOE) in the management of patients with suspected traumatic lesions of the thoracic aorta (TLA) and its branches; to assess the influence of the learning curve on the diagnostic accuracy of TOE for the identification of TLA. STUDY DESIGN: Retrospective study. PATIENTS: The study included 150 patients (age: 41 +/- 17; Injury Severity Scale score: 31 +/- 17) who were admitted during a 4-year period for severe blunt chest trauma and who underwent a TOE study. METHODS: TOE were performed with either a monoplane (n = 54) or a multiplane probe (n = 96). In all cases, TLA were confirmed by angiography, computed tomography, surgery, or necropsy. Initially performed routinely, angiography was subsequently indicated when the TOE study was inconclusive or when a disruption of supraaortic arteries was suspected. Echocardiographic studies were reviewed by an experienced reader who was unaware of the medical history and initial conclusions. To evaluate the influence of the learning curve on the diagnostic accuracy of TOE, these conclusions were compared with the initial interpretations. RESULTS: A TLA was recognized in 25 patients out of 150 (17%), and evidenced using TOE in 22 of them. Three false negative and two false positive TOE results (needless thoracotomy) were recorded. After a learning period, the rate of inconclusive TOE studies decreased (18/150 vs 7/150: P < 0.05) and no false positive finding was recorded. The sensitivity and specificity of TOE for the diagnosis of TLA were 88 and 100%, and positive and negative predictive values were 100 and 97%, respectively. CONCLUSIONS: TOE is an accurate imaging technique for the diagnosis of TLA located at the aortic isthmus. However aortography becomes essential when injuries of the aorta branches are suspected. A learning period is required to improve the specificity of TOE for this indication.

Adult↗

PubMed1995

Retrograde nephrostomy: advantages, disadvantages, and the learning curve.

Establishment of a nephrostomy tract is a prerequisite for many endourologic procedures of the upper urinary tract. We reviewed our initial experience with 31 retrograde nephrostomies to determine the advantages and disadvantages and the learning curve for the procedure. All but one of the attempts were successful, and no complications were attributable to the nephrostomy puncture. The procedure time averaged 21.1 minutes in nondilated collecting systems but 32.0 minutes in hydronephrotic kidneys (P < 0.01). The mean procedure time in our first 10 successful cases was 36.2 minutes, but it decreased to 22.6 minutes in the second 10 successful cases (P < 0.02). Radiation exposure was also minimized early, with a mean fluoroscopy time of 3.5 minutes in our first 10 successful cases and 1.5 minutes in our second 10 successful cases (P < 0.02). Similarly, both procedure and fluoroscopy times decreased further in the most recent 10 successful cases. Retrograde nephrostomy is a safe procedure, is easier in a nondilated collecting system, and can be mastered with a short learning curve with minimal radiation exposure.

Adolescent↗

PubMed1992

Evaluation of the learning curve associated with uncemented primary porous-coated anatomic total hip arthroplasty.

The results of the first and second groups of 50 consecutive primary, uncemented porous-coated anatomic arthroplasties were analyzed to evaluate the learning curve associated with the procedure. Femoral fit, acetabular cup angle, femoral fracture rate, minimum two-year clinical hip ratings, and clinical symptoms were compared between the two groups. Significant improvement in achieving better femoral canal filling with the prosthesis and lower acetabular cup angle placements was documented in the second 50 cases. Although a definite learning curve in mastering the technique of uncemented total hip arthroplasty was observed, thigh pain rate and clinical ratings were not improved after two years.

Female↗

PubMed2003

[Transradial approach to coronary angiography and angioplasty: initial experience and learning curve].

INTRODUCTION: The transradial approach has emerged as an attractive alternative to the femoral approach for coronary angiography and interventions. We describe our experience with the transradial approach and analyze the influence of the learning curve. PATIENTS AND METHODS: The transradial approach was attempted in patients with a good radial pulse and normal Allen test. When feasible and clinically indicated, we attempted ad hoc intervention. We divided the study population into two groups: Group A (the first 200 cases) and B (all other patients). We compared the radial group with a matched femoral control group. RESULTS: We attempted the transradial approach in 526 patients (77.6% male; age 63.5 +/- 11.51), and obtained a success rate of 93.7%. We found differences between group A and B in the success rate (91.0 vs 95.4%, p = 0,04), duration of procedure [23 (16-29) vs. 19 (15-24) minutes; p < 0.001], and fluoroscopy time [6.4 (4.2-10) vs. 5.0 (3.0-7.7) minutes; p < 0,001]. At 24 h of follow-up, we found small hematomas in 9.4%, bleeding in 4.9%, and radial artery obstruction in 2.8%, with no cases of arteriovenous fistula, pseudoaneurysm, or need for vascular surgery. We attempted intervention in 169 patients with 258 lesions, achieving angiographic success in 96.1%. We found no differences in the characteristics of the lesions and patients, or in the angiographic success rate of the radial and femoral PTCA groups. CONCLUSIONS: The transradial approach is a safe and effective alternative to femoral catheterization. There is a significant learning curve associated with the successful performance of transradial procedures.

Angioplasty, Balloon, Coronary↗

PubMed2007

From proficiency to expert, when does the learning curve for robotic-assisted prostatectomies plateau? The Columbia University experience.

To describe our single-institution experience with our first 70 consecutive robotic-assisted laparoscopic prostatectomies (RLPs) with particular focus on effect of learning curve on operative time, length of stay and blood loss. We also report our short-term outcome data in this heterogeneous cohort of men with prostate cancer (PCa). We reviewed our institutional database for the first 70 consecutive RLPs performed by a single surgeon (DS) over a 21-month period (March 2003 to December 2004). Surgical, pathologic and postoperative outcomes were analyzed. In order to evaluate the impact of the surgeon's and institution's learning curve on outcomes, the cases were divided into quartiles and stratified accordingly to identify trends. Ninety-nine percent (69/70) of all procedures were successfully completed robotically. Mean blood loss, operative time and mean length of stay were 231 ml, 264 min and 1.9 days, respectively. At follow-up, 76% of all patients were fully continent (no pads) and 93% (62/67) had undetectable PSA. The most dramatic improvement in surgical outcomes was seen within the first quartile of cases; however a statistically significant improvement trend existed throughout the series. This included a downward trend in operative time (P < 0.00001), estimated blood loss (P < 0.00001), and length of hospital stay (P = 0.003). This trend continued when controlled for in a multivariate analysis. Our results compare favorably with other RLP series as well as conventional laparoscopic series. Proficiency is achieved within the first 20 cases; however surgical outcomes continue to improve for RLP throughout the first 70 cases and perhaps beyond.

Aged↗

PubMed1999

Sentinel node localization in primary melanoma: learning curve and results.

Ninety primary melanoma patients were studied to investigate the importance of adopting the simultaneous use of patent blue dye (PBD) and lymphoscintigraphy plus gamma detection probe to locate the sentinel node (SN). In total 135 SNs in 105 basins were visualized preoperatively under a gamma camera after lymphoscintigraphy. When a SN was identified intraoperatively, its radioactivity level and colour were verified and documented. Two of the SNs seen on lymphoscintigraphy were not found. Using PBD 78.52% of the SNs were identified; 95.5% were identified using the gamma detection probe. Using both methods together 98.5% of the SNs were detected. Twenty-two patients (24.4%) had pathologically positive SNs. The surgical learning curve was assessed for the two techniques. The learning curve associated with the methodology was important in finding the SN when using PBD associated with lymphoscintigraphy, but not when the gamma detection probe was used; we found a statistically significant reduction in the percentage of stained SNs found using PBD in the initial 14 SNs biopsied compared with the subsequent 121 nodes. This is important as not all institutions have access to a gamma probe. The time required to identify each SN was documented and analysed. The duration of the procedure was significantly shorter for stained SNs than for non-stained SNs, which support the use of both PBD and the gamma probe. In conclusion, SN biopsy should be performed by surgeons and nuclear medicine doctors in co-operation, both methods being adopted simultaneously to reduce the percentage of procedure failures.

Adolescent↗

PubMed2006

Autoshaped head poking in the mouse: a quantitative analysis of the learning curve.

In autoshaping experiments, we quantified the acquisition of anticipatory head poking in individual mice, using an algorithm that finds changes in the slope of a cumulative record. In most mice, upward changes in the amount of anticipatory poking per trial were abrupt, and tended to occur at session boundaries, suggesting that the session is as significant a unit of experience as the trial. There were large individual differences in the latency to the onset of vigorous responding. "Asymptotic" performance was unstable; large, bidirectional, and relatively enduring changes were common. Given the characteristics of the individual learning curves, it is unlikely that physiologically meaningful estimates of rate of learning can be extracted from group-average learning curves.

Animals↗

PubMed2006

Robotic cholecystectomy: learning curve, advantages, and limitations.

BACKGROUND: Robotic cholecystectomy is safe, feasible procedure. Initial studies showed significant set up time and operating time but no clear clinical advantage of the robotic involvement. We have investigated the learning curve, advantages and limitation of the procedure. MATERIAL AND METHODS: We reviewed all (n = 51) robotic cholecystectomies performed between July 2004 and December 2005. The surgery was performed using the da Vinci system. We recorded operative time, setup time of robotics instrumentation, conversion to laparoscopic or open cholecystectomy and complication of the procedure. RESULTS: Forty-eight of the 51 procedures (94%) were completed robotically. We did not experience any significant complications directly related to robotics surgery. The mean +/- SD operating time was 77 +/- 22.3 min. The mean setup time for robotics (from incision until robot was in place, including draping the robot) was 24 +/- 8.8 min. However, the setup time significantly improved as we gained more experience: from 30.6 +/- 10.7 min (first 16 cases) to 18.3 +/- 4.0 min (cases 33-48). The mean robotic time was 34 +/- 16.1 min. We observed no significant improvement in robotic procedure time. CONCLUSIONS: Robotic cholecystectomy offers significant advantages such as three-dimensional view, easier instrument manipulations and possibility of remote site surgery. We observed some shortcomings of robotic surgery such as need for larger and additional ports, and need for undocking the machine in case of cholangiography or change of patient position. Our data shows that the learning curve is between 16 to 32 procedures to significantly decrease the setup time and total operating time.

Adolescent↗