Learning curves in laparoscopic right-sided colon cancer surgery: a comparison of first-generation colorectal surgeon to advance laparoscopically trained surgeon

The learning curve of laparoscopic rectal cancer surgery of millennial surgeons: Lessons for a safe implementation in low- and middle-income countries

Objective

This study aimed to analyse the learning curve (LC) in laparoscopic rectal cancer resections of 2 millennial surgeons during the implementation of the first laparoscopic rectal cancer surgery programme in low- and middle-income country (LMIC) cancer centre.

Methods

All consecutive patients operated by two millennial surgeons for primary rectal adenocarcinoma between January 2018 and March 2020 were included. The LC was analysed for operative duration and conversion to open surgery using both cumulative sum (CUSUM) and/or variable life-adjusted display (VLAD) charts.

Results

Eighty-four patients were included, 45 (53.6%) men with a mean age of 57.3 years. Abdominoperineal resection was performed in 31 (36.9%) cases and resections were extended to other organs in 20 (23.8%) patients. Thirteen patients (15.5%) had conversion to open surgery. Using CUSUM, Learning curve based on conversion was completed at 12 cases for the first surgeon versus 10 cases for the second. While using VLAD and learning curve-CUSUM (LC-CUSUM), the cases needed were 26 vs 24 respectively. The median operative duration was 314 min with a LC completed at cases (17 vs. 26), and (18 vs. 29) using, respectively, standard and LC-CUSUM.

Conclusions

This study shows a safe and short LC of millennial surgeons during the implementation of a laparoscopic rectal cancer surgery in an LMIC cancer centre, and the valuable use of modern statistical methods in the prospective assessment of LC safety during surgical training.

Training curriculum in minimally invasive emergency digestive surgery: 2022 WSES position paper

BACKGROUND

Minimally invasive surgery (MIS), including laparoscopic and robotic approaches, is widely adopted in elective digestive surgery, but selectively used for surgical emergencies. The present position paper summarizes the available evidence concerning the learning curve to achieve proficiency in emergency MIS and provides five expert opinion statements, which may form the basis for developing standardized curricula and training programs in emergency MIS.

METHODS

This position paper was conducted according to the World Society of Emergency Surgery methodology. A steering committee and an international expert panel were involved in the critical appraisal of the literature and the development of the consensus statements.

RESULTS

Thirteen studies regarding the learning curve in emergency MIS were selected. All but one study considered laparoscopic appendectomy. Only one study reported on emergency robotic surgery. In most of the studies, proficiency was achieved after an average of 30 procedures (range: 20-107) depending on the initial surgeon's experience. High heterogeneity was noted in the way the learning curve was assessed. The experts claim that further studies investigating learning curve processes in emergency MIS are needed. The emergency surgeon curriculum should include a progressive and adequate training based on simulation, supervised clinical practice (proctoring), and surgical fellowships. The results should be evaluated by adopting a credentialing system to ensure quality standards. Surgical proficiency should be maintained with a minimum caseload and constantly evaluated. Moreover, the training process should involve the entire surgical team to facilitate the surgeon's proficiency.

CONCLUSIONS

Limited evidence exists concerning the learning process in laparoscopic and robotic emergency surgery. The proposed statements should be seen as a preliminary guide for the surgical community while stressing the need for further research.

Change point analysis validation of the learning curve in laparoscopic colorectal surgery: Experience from a non-structured training setting

BACKGROUND

The introduction of minimal invasive principles in colorectal surgery was a major breakthrough, resulting in multiple clinical benefits, at the cost, though, of a notably steep learning process. The development of structured nation-wide training programs led to the easier completion of the learning curve; however, these programs are not yet universally available, thus prohibiting the wider adoption of laparoscopic colorectal surgery.

AIM

To display our experience in the learning curve status of laparoscopic colorectal surgery under a non-structured training setting.

METHODS

We analyzed all laparoscopic colorectal procedures performed in the 2012-2019 period under a non-structured training setting. Cumulative sum analysis and change-point analysis (CPA) were introduced.

RESULTS

Overall, 214 patients were included. In terms of operative time, CPA identified the 110^th case as the first turning point. A plateau was reached after the 145^th case. Subgroup analysis estimated the 58^th for colon and 52^nd case for rectum operations as the respective turning points. A learning curve pattern was confirmed for pathology outcomes, but not in the conversion to open surgery and morbidity endpoints.

CONCLUSION

The learning curves in our setting validate the comparability of the results, despite the absence of National or Surgical Society driven training programs.

Cumulative Sum Analysis of the Operator Learning Curve for Robot-Assisted Mayo Clinic Level I-IV Inferior Vena Cava Thrombectomy Associated with Renal Carcinoma: A Study of 120 Cases at a Single Center

Background

This study aimed to use cumulative sum analysis of the operator learning curve for robot-assisted Mayo Clinic level I–IV inferior vena cava (IVC) thrombectomy associated with renal carcinoma, and describes the development of an optimized operative procedure at a single center.

Material/Methods

A retrospective study included 120 patients with Mayo Clinic level I–IV IVC thrombus who underwent robotic surgery between 2013 and 2018. Points in the learning curve were identified using cumulative sum analysis, and their impact was assessed by multiple regression analysis. Perioperative indicators analyzed included operative time, estimated blood loss, early complications, and the 90-day progression rate.

Results

Cumulative sum analysis identified three phases in the learning curve of robot-assisted IVC thrombectomy. The median operative time decreased from 265 min (range, 212–401 min) to 207 min (range, 146–276 min) (p=0.003), the median estimated blood loss decreased from 775 ml (range, 413–1500 ml) to 300 ml (range, 163–813 ml) (p=0.006), and the early complication rate decreased from 52.5% to 15.0% (p<0.001). Multivariate analysis showed that for an initial 40 cases and a further 80 cases, the learning phase, the affected side, the Mayo Clinic level, and the surgical method were independent factors that affected operative time, estimated blood loss, and the rate of early complications.

Conclusions

Experience from an initial 40 cases and a further 80 cases of Mayo Clinic level I–IV IVC thrombectomy associated with renal carcinoma were found to provide acceptable surgical and clinical outcomes.

Learning curve and short-term outcomes of modularized LADG for advanced gastric cancer: A retrospective study

Laparoscopy-assisted distal gastrectomy (LADG) is a complicated procedure. To reduce the difficulty of the operation and standardize the surgical procedure, we explored a new operation mode, which we termed modularized LADG (MLADG). To further extend the new operation mode, we conducted this study to evaluate the short-term outcomes of MLADG for advanced gastric cancer, and determine the learning curve.Data from 100 consecutive patients who received LADG between October 2016 and October 2017 were retrospectively analyzed. Short-term outcomes, such as operation time and intraoperative blood loss, were evaluated, and the learning curve was calculated.For MLADG, the mean operation time was 168.2 ± 13.0 minutes, the mean intraoperative blood loss was 93.6 ± 29.1 ml, the mean number of harvested lymph nodes was 28.6 ± 4.2, and conversion to open surgery occurred in only 1 case. In addition, MLADG had an acceptable postoperative complication incidence and fast postoperative recovery. After the first 20 cases, the operation skill reached a mature and stable level.Our results indicate that MLADG is an oncologically feasible and technically safe surgical procedure. For the trainees with rich experience in open distal gastrectomy, the learning curve is considered to be completed after 20 MLADG cases.

The Learning Curve in Surgical Practice and Its Applicability to Rhinoplasty

The learning curve as a concept has been considered, discussed and debated in medical education and healthcare for over two decades. The precise usage has been recognised in surgical disciplines both broad specialties and sub-specialties. Rollin Daniel in his book stated that, rhinoplasty is the most difficult of all cosmetic operations for three reasons, (a) nasal anatomy is highly variable, (b) the procedure must correct form and function and (c) the final result must meet the patients expectations. With this in mind a study was carried on the perception of learning curve in rhinoplasty based on a surgeon questionnaire at Marien Hospital, Stuttgart, Germany under Prof. Gubisch. Aims of the study were, (1) to extract the perception of learning curve of Rhinoplasty from surgeons across a spectrum of experience, i.e. less experienced to experienced, (2) To calculate the perception of learning curve in rhinoplasty as for other surgical procedures i.e. minimum number, interquartile range, surgical time, accelerators, (3) To chart-out a road-map for a novice rhinoplasty surgeon for continued improvement in surgical skills and ability. The conclusion derived was the concept of learning curve in rhinoplasty cannot be applied to the operation of Septo-Rhinoplasty as a whole because the two factors i.e. interquartile range and minimum number to achieve proficiency have a wide range and cannot be generalized. It is thought that each type of Rhinoplasty should be dealt with separately and learning curve calculated accordingly, i.e. hump reduction, crooked nose and augmentation rhinoplasty.

Validation of the VBLaST pattern cutting task: a learning curve study

BACKGROUND

Mastery of laparoscopic skills is essential in surgical practice and requires considerable time and effort to achieve. The Virtual Basic Laparoscopic Skill Trainer (VBLaST-PC^©) is a virtual simulator that was developed as a computerized version of the pattern cutting (PC) task in the Fundamentals of Laparoscopic Surgery (FLS) system. To establish convergent validity for the VBLaST-PC^©, we assessed trainees' learning curves using the cumulative summation (CUSUM) method and compared them with those on the FLS.

METHODS

Twenty-four medical students were randomly assigned to an FLS training group, a VBLaST training group, or a control group. Fifteen training sessions, 30 min in duration per session per day, were conducted over 3 weeks. All subjects completed pretest, posttest, and retention test (2 weeks after posttest) on both the FLS and VBLaST^© simulators. Performance data, including time, error, FLS score, learning rate, learning plateau, and CUSUM score, were analyzed.

RESULTS

The learning curve for all trained subjects demonstrated increasing performance and a performance plateau. CUSUM analyses showed that five of the seven subjects reached the intermediate proficiency level but none reached the expert proficiency level after 150 practice trials. Performance was significantly improved after simulation training, but only in the assigned simulator. No significant decay of skills after 2 weeks of disuse was observed. Control subjects did not show any learning on the FLS simulator, but improved continually in the VBLaST simulator.

CONCLUSIONS

Although VBLaST^©- and FLS-trained subjects demonstrated similar learning rates and plateaus, the majority of subjects required more than 150 trials to achieve proficiency. Trained subjects demonstrated improved performance in only the assigned simulator, indicating specificity of training. The virtual simulator may provide better opportunities for learning, especially with limited training exposure.

Convergent validation and transfer of learning studies of a virtual reality-based pattern cutting simulator

INTRODUCTION

Research has clearly shown the benefits of surgical simulators to train laparoscopic motor skills required for positive patient outcomes. We have developed the Virtual Basic Laparoscopic Skill Trainer (VBLaST) that simulates tasks from the Fundamentals of Laparoscopic Surgery (FLS) curriculum. This study aims to show convergent validity of the VBLaST pattern cutting module via the CUSUM method to quantify learning curves along with motor skill transfer from simulation environments to ex vivo tissue samples.

METHODS

18 medical students at the University at Buffalo, with no prior laparoscopic surgical skills, were placed into the control, FLS training, or VBLaST training groups. Each training group performed pattern cutting trials for 12 consecutive days on their respective simulation trainers. Following a 2-week break period, the trained students performed three pattern cutting trials on each simulation platform to measure skill retention. All subjects then performed one pattern cutting task on ex vivo cadaveric peritoneal tissue. FLS and VBLaST pattern cutting scores, CUSUM scores, and transfer task completion times were reported.

RESULTS

Results indicate that the FLS and VBLaST trained groups have significantly higher task performance scores than the control group in both the VBLaST and FLS environments (p < 0.05). Learning curve results indicate that three out of seven FLS training subjects and four out of six VBLaST training subjects achieved the "senior" performance level. Furthermore, both the FLS and VBLaST trained groups had significantly lower transfer task completion times on ex vivo peritoneal tissue models (p < 0.05).

CONCLUSION

We characterized task performance scores for trained VBLaST and FLS subjects via CUSUM analysis of the learning curves and showed evidence that both groups have significant improvements in surgical motor skill. Furthermore, we showed that learned surgical skills in the FLS and VBLaST environments transfer not only to the different simulation environments, but also to ex vivo tissue models.

Lessons learned from a comparative analysis of surgical outcomes of and learning curves for laparoscopy-assisted distal gastrectomy

Purpose

Before expanding our indications for laparoscopic gastrectomy to advanced gastric cancer and adopting reduced port laparoscopic gastrectomy, we analyzed and audited the outcomes of laparoscopy-assisted distal gastrectomy (LADG) for adenocarcinoma; this was done during the adoptive period at our institution through the comparative analysis of short-term surgical outcomes and learning curves (LCs) of two surgeons with different careers.

Materials and Methods

A detailed comparative analysis of the LCs and surgical outcomes was done for the respective first 95 and 111 LADGs performed by two surgeons between July, 2006 and June, 2011. The LCs were fitted by using the non-linear ordinary least squares estimation method.

Results

The postoperative morbidity and mortality rates were 14.6% and 0.0%, respectively, and there was no significant difference in the morbidity rates (12.6% vs. 16.2%, P=0.467). More than 25 lymph nodes were retrieved by each surgeon during LADG procedures. The LCs of both surgeons were distinct. In this study, a stable plateau of the LC was not achieved by both surgeons even after performing 90 LADGs.

Conclusions

Regardless of the experience with gastrectomy or laparoscopic surgery for other organs, or the age of surgeon, the outcome was quite acceptable; the learning process differ according to the surgeon's experience and individual characteristics.

Attaining surgical competency and its implications in surgical clinical trial design: a systematic review of the learning curve in laparoscopic and robot-assisted laparoscopic colorectal cancer surgery

BACKGROUND

Laparoscopic surgery is increasingly used in the treatment of colorectal cancer and more recently robotic assistance has been advocated. However, the learning curve to achieve surgical proficiency in laparoscopic surgery is ill-defined and subject to many influences. The aim of this review was to comprehensively appraise the literature on the learning curve for laparoscopic and robotic colorectal cancer surgery, and to quantify attainment of surgical proficiency and its implications in surgical clinical trial design.

METHODS

A systematic review using a defined search strategy was performed. Included studies had to state an explicit numerical value of the learning curve evaluated by a single parameter or multiple parameters.

RESULTS

Thirty-four studies were included, 28 laparoscopic and 6 robot assisted. Of the laparoscopic studies, nine defined the learning curve on the basis of a single parameter. Nine studies used more than one parameter to define learning, and 11 used a cumulative sum (CUSUM) analysis. One study used both a multiparameter and CUSUM analysis. The definition of proficiency was subjective, and the number of operations to achieve it ranged from 5 to 310 cases for laparoscopic and 15-30 cases for robotic surgery.

CONCLUSIONS

The learning curve in laparoscopic colorectal surgery is multifaceted and often ill-defined, with poor descriptions of mentorship/supervision. Further, the quantification to attain proficiency is variable. The use of a single parameter to quantify this is simplistic. Multidimensional assessment is recommended; as part of this, the CUSUM model, which assesses trends in multiple surgical outcomes, is useful and appropriate when assessing the learning curve in a clinical setting.

Gastric tube necrosis following minimally invasive oesophagectomy is a learning curve issue

INTRODUCTION

Gastric tube necrosis following oesophagectomy is thought to have an increased association with a minimally invasive technique. Some suggest gastric ischaemic preconditioning may reduce ischaemic complications. We discuss our series of 155 consecutive minimally invasive oesophagectomies (MIOs), including a number of cases of gastric tube ischaemia, of which 4 (2.6%) developed conduit necrosis.

METHODS

Data were collected prospectively of MIOs carried out by a single surgeon between 2005 and 2011. Cases of gastric tube necrosis were identified.

RESULTS

Overall, 155 patients were identified. The inpatient mortality rate was 2.6%. Gastric tube necrosis occurred in four patients (2.6%). An ultrasonic dissector injury to the gastroepiploic arcade had occurred in two cases. In another case, the gastric tube was strangulated in the hiatus. In the remaining case, no clear mechanical cause was identified. All 4 cases occurred within the first 73 cases. The gastric tube necrosis rate of the first 50 cases versus cases 51-155 was 4% and 2% respectively (p=0.5948). The anastomotic leak rate in these two cohorts was 18% and 7% respectively (p=0.0457). There was a significant reduction in overall gastric tube complications from 22% to 10% following the learning curve of the initial 50 cases (p=0.0447).

CONCLUSIONS

In our series, gastric tube necrosis appears to be a learning curve issue. Prophylactic measures such as ischaemic preconditioning become less relevant as the operating surgeon's experience increases. Instead, meticulous attention to preserving the gastroepiploic arcade, avoidance of tension in the tube and careful positioning of the gastric conduit through an adequately sized hiatus are key factors.

Measuring the surgical 'learning curve': methods, variables and competency

OBJECTIVES

To describe how learning curves are measured and what procedural variables are used to establish a 'learning curve' (LC). To assess whether LCs are a valuable measure of competency.

PATIENTS AND METHODS

A review of the surgical literature pertaining to LCs was conducted using the Medline and OVID databases.

RESULTS

Variables should be fully defined and when possible, patient-specific variables should be used. Trainee's prior experience and level of supervision should be quantified; the case mix and complexity should ideally be constant. Logistic regression may be used to control for confounding variables. Ideally, a learning plateau should reach a predefined/expert-derived competency level, which should be fully defined. When the group splitting method is used, smaller cohorts should be used in order to narrow the range of the LC. Simulation technology and competence-based objective assessments may be used in training and assessment in LC studies.

CONCLUSIONS

Measuring the surgical LC has potential benefits for patient safety and surgical education. However, standardisation in the methods and variables used to measure LCs is required. Confounding variables, such as participant's prior experience, case mix, difficulty of procedures and level of supervision, should be controlled. Competency and expert performance should be fully defined.

Characterizing the learning curve of the VBLaST-PT(©) (Virtual Basic Laparoscopic Skill Trainer)

BACKGROUND

Mastering laparoscopic surgical skills requires considerable time and effort. The Virtual Basic Laparoscopic Skill Trainer (VBLaST-PT(©)) is being developed as a computerized version of the peg transfer task of the Fundamentals of Laparoscopic Surgery (FLS) system using virtual reality technology. We assessed the learning curve of trainees on the VBLaST-PT(©) using the cumulative summation (CUSUM) method and compared them with those on the FLS to establish convergent validity for the VBLaST-PT(©).

METHODS

Eighteen medical students from were assigned randomly to one of three groups: control, VBLaST-training, and FLS-training. The VBLaST and the FLS groups performed a total of 150 trials of the peg-transfer task over a 3-week period, 5 days a week. Their CUSUM scores were computed based on predefined performance criteria (junior, intermediate, and senior levels).

RESULTS

Of the six subjects in the VBLaST-training group, five achieved at least the "junior" level, three achieved the "intermediate" level, and one achieved the "senior" level of performance criterion by the end of the 150 trials. In comparison, for the FLS group, three students achieved the "senior" criterion and all six students achieved the "intermediate" and "junior" criteria by the 150th trials. Both the VBLaST-PT(©) and the FLS systems showed significant skill improvement and retention, albeit with system specificity as measured by transfer of learning in the retention test: The VBLaST-trained group performed better on the VBLaST-PT(©) than on FLS (p = 0.003), whereas the FLS-trained group performed better on the FLS than on VBLaST-PT(©) (p = 0.002).

CONCLUSIONS

We characterized the learning curve for a virtual peg transfer task on the VBLaST-PT(©) and compared it with the FLS using CUSUM analysis. Subjects in both training groups showed significant improvement in skill performance, but the transfer of training between systems was not significant.

Breast models: a useful tool for instruction

Background

In the late '80s the successes of the laparoscopic surgery for gallbladder disease laid the foundations on the modern use of this surgical technique in a variety of diseases. In the last 20 years, laparoscopic colorectal surgery had become a popular treatment option for colorectal cancer patients.

Discussion

Many studies emphasized on the benefits stating the significant advantages of the laparoscopic approach compared with the open surgery of reduced blood loss, early return of intestinal motility, lower overall morbidity, and shorter duration of hospital stay, leading to a general agreement on laparoscopic surgery as an alternative to conventional open surgery for colon cancer. The reduced hospital stay may also decrease the cost of the laparoscopic surgery for colorectal cancer, despite th higher operative spending compared with open surgery. The average reduction in total direct costs is difficult to define due to the increasing cost over time, making challenging the comparisons between studies conducted during a time range of more than 10 years. However, despite the theoretical advantages of laparoscopic surgery, it is still not considered the standard treatment for colorectal cancer patients due to technical limitations or the characteristics of the patients that may affect short and long term outcomes.

Conclusions

The laparoscopic approach to colectomy is slowly gaining acceptance for the management of colorectal pathology. Laparoscopic surgery for colon cancer demonstrates better short-term outcome, oncologic safety, and equivalent long-term outcome of open surgery. For rectal cancer, laparoscopic technique can be more complex depending on the tumor location. The advantages of minimally invasive surgery may translate better care quality for oncological patients and lead to increased cost saving through the introduction of active enhanced recovery programs which are likely cost-effective from the perspective of the hospital health-care providers.