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PubMed2005

Sentinel node localization in breast cancer using intradermal dye injection: results, influencing factors and learning curve.

To evaluate the identification rate, false negative rate, concordance, negative predictive value of sentinel node localization in breast cancer using intradermal isosulfan blue injection whether this is accurate enough for surgical approach in breast cancer surgery and whether there is a significant learning curve for this technique. Factors affecting the outcomes of the procedure are also determined. From August 2002 to September 2003, 66 cases of stage 0-IIIB operable breast cancer patients underwent sentinel lymph node biopsy before standard breast cancer operation. Overall, identification rate was 80.3%, false negative rate was 10.6%, concordance was 86.8%, negative predictive value was 83.3%, sentinel node was the only node that was positive in 45.5%, and mean operative time was 55.1 minutes. Factors found to lower sentinel node identification rate are neoadjuvant chemotherapy and large tumor (T3-4) while previous excision was not found to affect the identification rate. There is significant learning curve in this technique and this should be performed at least 40-45 cases in the learning phase to accomplish a high identification rate and lower false negative rate before implicating into clinical practice.

Adolescent↗

PubMed2000

Laparoscopic hernia repair: the learning curve.

The performance of a laparoscopic inguinal hernia repair requires unique technical and cognitive skills which, until recently, were not routinely taught to general surgeons. The initial experience of three surgeons with laparoscopic hernia repair was audited prospectively to assess the learning curve for the technique. From March 1992 to June 1994, transabdominal preperitoneal (TAP) mesh repair was attempted on 172 consecutive inguinal hernias. Three procedures were converted to traditional repairs. The three independent surgeons that performed the repairs had minimal or no prior clinical experience with the technique in the role as primary surgeon. The hernia repairs were divided into two groups. Group 1 consisted of the first 90 hernia repairs in the series, 30 repairs per surgeon. This group was compared to the subsequent 82 repairs (group 2), approximately 27 repairs per surgeon. Patients were followed up for a median of 31 months. Group 1 had more patients who were hospitalized overnight (37% versus 31%), a greater rate of conversion (2.2% versus 1.2%), a higher complication rate (11.7% versus 0%), a higher recurrence rate (12.2% versus 0%), and a longer delay in the return to full activity (11 weeks versus 8 weeks). Also, overall patient satisfaction with their hernia repair was slightly greater in group 2 (score, 9.0/10 versus 8.2/10). The lack of prior experience with the TAP technique (one surgeon) was associated with a marked increase in the number of conversions (two of three total conversions), complications (four of eight total), and hernia recurrences (8 of 11 total). This study demonstrates that a surgeon's initial experience with laparoscopic herniorrhaphy is associated with an identifiable learning curve. Significant improvements in complication and recurrence rates and overall patient satisfaction can be expected after the initial learning phase. Also, a complete lack of prior experience with laparoscopic herniorrhaphy is associated with a higher rate of conversion and significant increases in complications and hernia recurrences.

Adolescent↗

PubMed2006

Bypassing the learning curve in permanent seed implants using state-of-the-art technology.

PURPOSE: The aim of this study was to demonstrate, based on clinical postplan dose distributions, that technology can be used efficiently to eliminate the learning curve associated with permanent seed implant planning and delivery. METHODS AND MATERIALS: Dose distributions evaluated 30 days after the implant of the initial 22 consecutive patients treated with permanent seed implants at two institutions were studied. Institution 1 (I1) consisted of a new team, whereas institution 2 (I2) had performed more than 740 preplanned implantations over a 9-year period before the study. Both teams had adopted similar integrated systems based on three-dimensional (3D) transrectal ultrasonography, intraoperative dosimetry, and an automated seed delivery and needle retraction system (FIRST, Nucletron). Procedure time and dose volume histogram parameters such as D90, V100, V150, V200, and others were collected in the operating room and at 30 days postplan. RESULTS: The average target coverage from the intraoperative plan (V100) was 99.4% for I1 and 99.9% for I2. D90, V150, and V200 were 191.4 Gy (196.3 Gy), 75.3% (73.0%), and 37.5% (34.1%) for I1 (I2) respectively. None of these parameters shows a significant difference between institutions. The postplan D90 was 151.2 Gy for I1 and 167.3 Gy for I2, well above the 140 Gy from the Stock et al. analysis, taking into account differences at planning, results in a p value of 0.0676. The procedure time required on average 174.4 min for I1 and 89 min for I2. The time was found to decrease with the increasing number of patients. CONCLUSION: State-of-the-art technology enables a new brachytherapy team to obtain excellent postplan dose distributions, similar to those achieved by an experienced team with proven long-term clinical results. The cost for bypassing the usual dosimetry learning curve is time, with increasing team experience resulting in shorter treatment times.

Brachytherapy↗

PubMed1999

The effect of the learning curve on the duration and peri-operative complications of laparoscopically assisted vaginal hysterectomy.

BACKGROUND: Hysterectomy is the commonest elective major gynecological operation and the laparoscopic approach is increasingly an option. We evaluated the influence of the learning curve on the duration of surgery and also the peri-operative complications. METHODS: A retrospective study of the case records of patients who had laparoscopically assisted vaginal hysterectomy with or without bilateral salpingo-oophorectomy between August 1993 and July 1997. RESULTS: Over a four year period 86 cases of laparoscopically assisted vaginal hysterectomy with or without bilateral salpingo-oophorectomy were performed; the main indication being menstrual disorders. The mean duration of surgery was 116 minutes. There was a significant difference in the mean duration of surgery between the first two years (123 minutes) and the last two years (110 minutes) (p<0.02). The difference in the mean duration of surgery performed either by consultants or senior registrars under supervision (115 versus 116 minutes) was not significant (p>0.05). The overall complication rate was 16% with a majority (85%) occurring in the first two years of the study period. Three cases (5%) were converted to conventional abdominal hysterectomy. After the initial learning phase there was a significant reduction in the complication rates. CONCLUSIONS: The impact of the learning curve on the duration of surgery is gradual. The perceived duration of surgery should not be a disincentive for senior trainees provided they are already proficient in minor laparoscopic surgery, cases are suitably selected and adequate supervision is provided.

Elective Surgical Procedures↗

PubMed2006

Learning curve for percutaneous radiofrequency ablation of pulmonary metastases from colorectal carcinoma: a prospective study of 70 consecutive cases.

BACKGROUND: Percutaneous radiofrequency ablation (RFA) for inoperable colorectal pulmonary metastases is associated with a morbidity rate of 30% to 40%. A learning curve in this treatment approach has not been documented before. METHODS: The clinical and treatment-related data regarding 70 consecutive percutaneous RFA procedures for inoperable colorectal pulmonary metastases were collected prospectively. A comparison between the initial 35 cases (group 1) and the subsequent 35 cases (group 2) was performed. Univariate and multivariate analyses were conducted to identify the significant risk factors for overall morbidity, pneumothorax, and chest drain requirement. RESULTS: There was no hospital mortality. The overall morbidity rate was 37%. The rate of pneumothorax was 27%. Twelve patients (17%) required chest drain insertion for pneumothorax. There was a significant decline in the incidence of overall morbidity, pneumothorax, and chest drain requirement in group 2 as compared with group 1. Both the number of lung metastases ablated and the RFA treatment period (group 1 vs. group 2) were independent risk factors for overall morbidity, pneumothorax, and chest drain requirement. Distribution of lung metastases (unilateral vs. bilateral) was an independent risk factor for overall morbidity and pneumothorax, but not for chest drain requirement. CONCLUSIONS: There is a learning curve for percutaneous lung RFA. With accumulated experience in this procedure, a low morbidity rate can be achieved.

Aged↗

PubMed2000

Is there a learning curve in diagnosing urolithiasis with noncontrast helical computed tomography?

OBJECTIVE: To report one department's experience with helical computed tomographic (HCT) evaluation of patients with suspected renal colic to diagnose ureteral calculi; to determine whether there is a learning curve in performing HCT in this context; and to determine whether HCT for the evaluation of renal colic exposes patients to more radiation than the standard intravenous pyelography (IVP) combined with nephrotomography. METHODS: All patients presenting to the emergency department with flank or abdominal pain were evaluated with nonreformatted noncontrast HCT. To determine changes in diagnostic accuracy, patients were divided into 2 groups: those evaluated between September 1996 and January 1997 (group 1, 67 patients), and those seen from February to June 1997 (group 2, 53 patients). A radiation exposure study was performed using phantoms, and radiation exposure for HCT, IVP and nephrotomography was measured. RESULTS: Review of HCT scans to diagnose ureteral calculi had a sensitivity of 91.7%, specificity of 82.6%, and accuracy of 87.2% in group 1, and a sensitivity of 95.5%, specificity of 86.7%, and accuracy of 91.9% in group 2. Patients undergoing IVP with nephrotomography were exposed to an effective dose equivalent of 343 mrem (dSv) (for men) and 664 mrem (for women). The effective dose equivalent for an HCT scan was 180 mrem. CONCLUSION: HCT offers excellent, rapid diagnostic accuracy without the need for intravenous contrast medium and with a lower radiation exposure level than IVP in evaluating patients with acute flank pain. There is a small but real learning curve in evaluating patients with acute flank pain with HCT.

Adolescent↗

PubMed2004

Impact of learning curve in laparoscopic radical prostatectomy on margin status: prospective study of first 100 procedures performed by one surgeon.

PURPOSE: To describe the experience of a single surgeon with his first 100 laparoscopic radical prostatectomies and determine the impact of the learning curve on the surgical margin status according to the rate of nervesparing procedures. PATIENTS AND METHODS: Between December 2000 and April 2002, 100 laparoscopic radical prostatectomies were performed by one surgeon without any selection of patients and without the help of any other surgeon. The procedures were divided in four groups of 25 consecutive cases. There was no significant difference among the groups in terms of age, clinical and pathological stage, or Gleason score. Nerve-sparing (NS) dissection was performed when the procedure was easy. Positive surgical margins (SM+) were measured and classified according to their location. RESULTS: The overall rate of SM+ was 12.8% in pT2 and 31.8% in pT3 tumors. The SM+ rate was not significantly different among the groups. In contrast, the number of NS dissections (49 patients) increased from group 1 to group 4. Both the positive margin length and the rate of multiple positive margins were significantly lower in the 50 most recent patients. CONCLUSION: Nerve-sparing surgery was performed with increasing frequency during this learning curve without compromising the surgical margins. The results suggest that experience could lead to a decrease of both the positive margin length and the rate of multiple positive margins. The impact on cancer control and potency is under evaluation.

Humans↗

PubMed1998

Institutional learning curve of surgeon-performed trauma ultrasound.

BACKGROUND: Sonography has become the primary mode for the initial evaluation of abdominal injury in many trauma centers. However, the rate at which nonradiologists become proficient in this technique remains controversial. OBJECTIVE: To assess the learning curve for this technique in a single institution. DESIGN: Retrospective review of sonographic examinations for trauma performed by senior surgical residents during a 24-month period at an American College of Surgeons-verified level I trauma center. SETTING: University-affiliated private hospital. PATIENTS AND METHODS: Before the initiation of a program of surgeon-performed trauma ultrasound, senior surgical residents (postgraduate years 4 and 5) received 11.5 hours of hands-on and didactic instruction in the focused ultrasound examination for trauma. This examination then became a standard component of the evaluation of injured patients. Subsequent groups of senior residents received 8 hours of instruction at the onset of new academic years, 6 and 18 months, respectively, after the initial course. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were then calculated for each 6-month period after the introduction of trauma sonography. RESULTS: During the 24-month study period, 902 sonographic examinations were performed. No statistically significant differences were noted in sensitivity, specificity, accuracy, positive predictive value, or negative predictive value for any 6-month period of study when compared with the other 6-month periods or with the values calculated for the entire study period. CONCLUSIONS: Senior surgical residents are capable of performing the focused ultrasound examination for trauma with a high level of skill after a concise introductory course. A learning curve was not apparent in our series. Criteria for being permitted to perform trauma sonography that include the requirement of a large number of examinations or extensive proctoring should be reassessed.

Abdominal Injuries↗

PubMed1998

An objective experimental assessment of the learning curve for laparoscopic surgery: the example of pelvic and para-aortic lymph node dissection.

OBJECTIVES: To date the number of procedures required to become competent to perform new laparoscopic surgical techniques is not known. STUDY DESIGN: The pig model was chosen for assessment of the learning curve associated with an advanced laparoscopic procedure. A unilateral laparoscopic pelvic lymphadenectomy was performed by two residents and a laparoscopic para-aortic lymphadenectomy was performed by a fellow on a series of 20 pigs. The quality of the dissection was checked by immediate laparotomy by an independent observer. RESULTS: The operative objectives were: (a) There should be less than 5% residual lymph nodes. (b) The operating time should be less than 30 min for pelvic and less than 100 min for para-aortic lymphadenectomy. (c) Avoiding conversion because of complications. This target was achieved after 7 and 9 pigs respectively for pelvic lymphadenectomy and after 14 pigs for para-aortic lymphadenectomy. CONCLUSION: It is feasible to assess the learning curve of trainee surgeons while performing laparoscopic pelvic and para-aortic lymphadenectomy on pigs. A training programme such as this should prevent complications due to inexperience and should satisfy ethical and medico-legal considerations.

Animals↗

PubMed2006

Learning curve in laparoscopic colorectal surgery: our first 100 patients.

BACKGROUND: Recent data confirming the oncologic safety of laparoscopic colectomy for cancer as well as its potential benefits will likely motivate more surgeons to perform laparoscopic colorectal surgery. OBJECTIVES: To assess factors related to the learning curve of laparoscopic colorectal surgery, such as the number of operations performed, the type of procedures, major complications, and oncologic resections. METHODS: We evaluated the data of our first 100 elective laparoscopic colorectal operations performed during a 2 year period and compared the first 50 cases with the following 50. RESULTS: The mean age of the study population was 66 years and 49% were males. Indications included cancer, polyps, diverticular disease, Crohn's disease, and others, in 50%, 23%, 13%, 7% and 7% respectively. Mean operative time was 170 minutes. One patient died (massive pulmonary embolism). Significant surgical complications occurred in 10 patients (10%). Hospital stay averaged 8 days. Comparison of the first 50 procedures with the next 50 revealed a significant decrease in major surgical complications (20% vs. 0%). Mean operative time decreased from 180 to 160 minutes and hospital stay from 8.6 to 7.2 days. There was no difference in conversion rate and mean number of harvested nodes in both groups. Residents performed 8% of the operations in the first 50 cases compared with 20% in the second 50 cases. Right colectomies had shorter operative times and fewer conversions. CONCLUSIONS: There was a significant decrease in major complications after the first 50 laparoscopic colorectal procedures. Adequate oncologic resections may be achieved early in the learning curve. Right colectomies are less difficult to perform and are recommended as initial procedures.

Adult↗

PubMedDate not supplied

Bridging the knowledge gap. Trustee mentors shorten the learning curve for new board members.

Trustee mentors can shorten the learning curve dramatically for new board members--and it's a partnership of growing necessity as health care change and complexity accelerate.

Efficiency, Organizational↗

PubMed1990

An evaluation of the chorionic villus sampling learning curve.

Prior studies have identified a correlation between the rate of fetal loss (subsequent to chorionic villus sampling) and the operator's level of experience. However, centers performing only modest numbers of procedures during the initial phase of their programs have reported loss rates similar to those of the more active diagnostic units. Our personal experience would suggest that a "learning curve" for chorionic villus sampling does exist but that fetal loss may be an insensitive end point with which to evaluate the impact of cumulative performance. In an attempt to quantify the learning curve that we have appreciated subjectively, a detailed analysis of our initial experience with chorionic villus sampling was undertaken. Between May 1988 and August 1989, a total of 185 procedures were accomplished consecutively by one operator and form the basis for this analysis. Transcervical (n = 82) and transabdominal (n = 103) techniques were used for posterior and anterior-fundal placental locations, respectively. Three pregnancy losses occurred and insufficient material for analysis was retrieved in five patients. We observed a significant reduction in the required number of placental aspirations during the study interval (p less than 0.001). When analyzed separately, consecutive performances of the transabdominal technique demonstrated a significant reduction in the mean number of placental passes (p less than 0.00001) along with more efficient sampling (increased sample weight/aspiration attempt; p less than 0.01). Although the fetal loss rate is a critical measure of safety and may directly be related to operator experience, other measures of expertise (e.g., single-pass success rate) may be more appropriate indicators of competence and may be useful to centers wishing to initiate their own chorionic villus sampling programs.

Abortion, Spontaneous↗

PubMed2005

Medical learning curves and the Kantian ideal.

A hitherto unexamined problem for the "Kantian ideal" that one should always treat patients as ends in themselves, and never only as a means to other ends, is explored in this paper. The problem consists of a prima facie conflict between this Kantian ideal and the reality of medical practice. This conflict arises because, at least presently, medical practitioners can only acquire certain skills and abilities by practising on live, human patients, and given the inevitability and ubiquity of learning curves, this learning requires some patients to be treated only as a means to this end. A number of ways of attempting to establish the compatibility of the Kantian Ideal with the reality of medical practice are considered. Each attempt is found to be unsuccessful. Accordingly, until a way is found to reconcile them, we conclude that the Kantian ideal is inconsistent with the reality of medical practice.

Education, Medical↗

PubMed2004

[Learning curve and early complications of totally implantable venous access devices: is tutoring the solution for the problem?].

During the last years operators implanting totally implantable venous access devices (TIVADs), type of access, and kind of complications are changed. Aim of this work is to evaluate the incidence of early complications during the learning curve of residents in surgery or inexperienced surgeons, besides considering the tutoring to evaluate its rule to prevent early complications. TIVADs, implanted by residents in surgery or by inexperienced surgeons in the Department of Surgical Science Organ Transplantation and Advanced Technologies of University of Catania from January 1995 to October 2003, have been considered for the present study. Age and sex of the patients, indication, type of surgical access and early complications of the TIVADs have been considered. Early complications are those complications that occur within 30 day after the implant. Ninety-five TIVADs were implanted by surgical approach in 95 patients: 58 males (61%) and 37 females (39%), with a mean age of 55 years (range 31-79). Inexperienced surgeons performed 40 implants (42%) instead resident in surgery implanted 55 TIVADs (58%). The migration out of the vein of a catheter 20 days after the operation was the only complication recorded. TIVADs implant by cut-down technique represent the way to avoid early complications. The learning curve is short and the tutoring is limited at the first phase.

Adult↗

PubMed1996

Endosonographic T-staging of esophageal carcinoma: a learning curve.

BACKGROUND: It has been suggested that 50 endosonographic examination are necessary to attain sufficient skill to become accurate in the staging of esophageal carcinoma. METHODS: Since July 1991 all esophageal endosonographies have been performed by one investigator. The database, containing all examinations since July 1991, was reviewed to investigate the presence of a learning curve in T-staging of esophageal carcinoma by comparing the endosonographic T-stage with the pathologic T-stage. RESULTS: From July 1991 until April 1993, 231 endosonographies were performed for esophageal malignancies. Eighty-nine patients had been referred for preoperative staging and underwent surgical exploration. Seventy-one tumors were resected. The patients were split in two groups. Group I consisted of 36 patients examined between July 1991 and April 1992. In this period 100 endosonographies were performed. Group II consisted of 35 patients examined between April 1992 and March 1993. In this period 131 endosonographies were performed. Overall endosonographic T-staging was correct in 70%. The accuracy in group I was 58%; In group II 83% (p < 0.05). Overstaging was equally common in groups I and II (14%). Understaging was common in group I (28%), but rare in group II (3%). CONCLUSION: This study shows a definite learning curve for endosonographic T-staging of esophageal carcinoma. Acceptable accuracy rates could only be achieved after 100 examinations.

Clinical Competence↗

PubMed2005

Total knee arthroplasty with conventional or navigated technique: comparison of the learning curves in a community hospital.

We performed a comparative study of the short-term radiological and clinical results after implantation of an unconstrained TKA with preservation of the posterior cruciate ligament with a conventional (50 cases--group A) or navigated (50 cases--group B) technique. The primary criterion was the postoperative leg coronal alignment measured on 3-month postoperative anteroposterior long-leg radiographs by the HKA angle: the expected alignment was 180 degrees +/- 3 degrees. The mean post-operative HKA angle was 180 degrees +/- 3 degrees in group A and 180 degrees +/- 1 degrees in group B (p = 0.15). Thirty-four cases in group A and all 50 cases in group B were in the desired range (p < 0.001). The navigated system used in this study allowed for a significantly better alignment accuracy than the conventional implantation technique. Acceptable routine implantation was achieved during the time of the study (first 50 cases). We can thus hypothesise that the learning curve of the navigated technique used is not any longer than the learning curve of a conventional implantation technique.

Aged↗

PubMed1997

The "learning curve" of total hip arthroplasty.

Total hip arthroplasty (THA) is one of the major breakthroughs in modern orthopedics this century. Since its introduction in the early 1960s by Sir J. Charnley, it has become the most common form of arthroplasty. The art of performing THA has developed to a large extent, yet with the inevitable "price" of a learning curve. The rates of early and late complications reported in the orthopedic literature have been decreasing gradually, along with improved short- and long-term results. We report the results of two similar series of THA performed with an interval of 15 to 20 years, which show that the improvement of the results that form the learning curve of THA at our institution is statistically significant.

Aged↗

PubMed2002

Pudendal nerve terminal motor latency testing: assessing the educational learning curve: can we teach our own?

PURPOSE: Pudendal nerve terminal motor latency testing is useful as a diagnostic tool in fecal incontinence. It has also been used as a predictive factor in sphincteroplasty repairs. The technique is seldom taught and mastered in colorectal training programs. The purpose of this study was to assess a learning curve for teaching this procedure. METHODS: The student was a formally trained colorectal surgeon with no pudendal nerve terminal motor latency experience; the instructor has performed more than 3,000 pudendal nerve terminal motor latency studies. Fifty consecutive patients had manometry and pudendal nerve terminal motor latency testing. Both the student and instructor performed pudendal nerve terminal motor latency in a sequential fashion. Variables collected included pudendal nerve terminal motor latency, completion of test, time to complete test, and accuracy of the test. Variables were analyzed with paired t-test and chi-squared analysis. RESULTS: The study group included 41 female and 9 male patients. The average age of the patients was 53 years. Bowel complaints included constipation in 16 and incontinence in 34 patients. Data were analyzed in their entirety and at ten-patient intervals. The student tended to record longer latencies (P < 0.001). This led to false-positive rates of 23 and 21 percent, respectively, for left and right pudendal nerve terminal motor latency. On average, the time to complete the procedure was three times longer for the student than for the instructor (P < 0.001). At ten-patient intervals, the pudendal nerve terminal motor latency difference between the two groups disappeared at the 41-to-50-patient mark. CONCLUSION: Given the proper learning environment, pudendal nerve terminal motor latency testing can be mastered in a relatively short period. On the basis of this study, our estimation is 40 patients are required for a student to master this technique. The novice examiner can expect false-positive results early in the learning curve, and these should be validated accordingly.

Constipation↗