Defining a learning curve for laparoscopic colorectal resections

PURPOSE: The purpose of this review was to define the learning curve for laparoscopic colorectal resections. METHODS: A prospectively accumulated, computerized database of all laparoscopic colorectal resections performed by three surgeons between April 1991 and March 1999 was reviewed. RESULTS: A total of 461 consecutive resections were evenly distributed among three surgeons (141, 155, and 165). Median operating time was 180 minutes for Cases 1 to 30 in each surgeon's experience and declined to a steady state (150–167.5 minutes) for Cases 31 and higher. Subsequently, Cases 1 to 30 were considered early experience, whereas Cases 31 and higher were combined as late experience for statistical analysis. There were no significant differences between patients undergoing resections in the early experience and those undergoing resections in the late experience with respect to age, weight, or proportion of patients with malignancy, diverticulitis, or inflammatory bowel disease. There were greater proportions of males (42vs. 54 percent,P=0.046) and rectal resections performed (14vs. 32 percent,P=0.002) in the late experience. Trends toward declining rates of intraoperative complications (9vs. 7 percent,P=0.70) and conversion to open surgery (13.5vs. 9.7 percent,P=0.39) were observed with experience. Median operating time (180vs. 160 minutes,P<0.001) and overall length of postoperative hospital stay (6.5vs. 5 days,P<0.001) declined significantly with experience. There was no difference in the rate of postoperative complications between early and late experience (30vs. 32 percent,P=0.827). CONCLUSIONS: The learning curve for performing colorectal resections was approximately 30 procedures in this study, based on a decline in operating time, intraoperative complications, and conversion rate. Learning was also extended to clinical care because it was appreciated that patients could be discharged to their homes more quickly.Presented at the meeting of the Canadian Association of General Surgeons, Montreal, Canada, September 24 to 26, 1999.     

Minimally invasive colorectal surgery learning curve

The learning curve in minimally invasive colorectal surgery is a constant subject of discussion in the literature. Discordant data likely reflects the varying degrees of each surgeon’s experience in colorectal, laparoscopic or robotic surgery. Several factors are necessary for a successful minimally invasive colorectal surgery training program, including: Compliance with oncological outcomes; dissection along the embryological planes; constant presence of an expert tutor; periodic discussion of the morbidity and mortality rate; and creation of a dedicated, expert team.     

Review of single incision laparoscopic surgery in colorectal surgery

As surgical techniques continue to move towards less invasive techniques,single incision laparoscopic surgery(SILS),a hybrid between traditional multiport laparoscopy and natural orifice transluminal endoscopic surgery,was introduced to further the enhanced outcomes of multiport laparoscopy. The safety and feasibility of SILS for both benign and malignant colorectal disease has been proven. SILS provides the potential for improved cosmesis,postoperative pain,recovery time,and quality of life at the drawback of higher technical skill required. In this article,we review the history,describe the available technology and techniques,and evaluate the benefits and limitations of SILS for colorectal surgery in the published literature.     

Core value of laparoscopic colorectal surgery

Since laparoscopy was first used in cholecystectomy in 1987, it has developed quickly and has been used in most fields of traditional surgery. People have now accepted its advantages like small incision, quick recovery, light pain, beauty and short hospital stays. In early times, there are still controversies about the application of laparoscopy in malignant tumor treatments, especially about the problems of oncology efficacy, incision implantation and operation security. However, these concerns have been fully eliminated by evidences on the basis of evidence-basis medicine. In recent years, new minimally invasive technologies are appearing continually, but they still have challenges and may increase the difficulties of radical dissection and the risks of potential complications, so they are confined to benign or early malignant tumors. The core value of the laparoscopic technique is to ensure the high quality of tumor’s radical resection and less complications. On the basis of this, it is allowed to pursue more minimally invasive techniques. Since the development of laparoscopic colorectal surgery is rapid and unceasing, we have reasons to believe that laparoscopic surgery will become gold standard for colorectal surgery in the near future.     

A comparative clinical study of short-term results of laparoscopic surgery for rectal cancer during the learning curve

Objectives The aim of this study was to assess the results of laparoscopic surgery for rectal carcinoma (LSRC) during the learning curve throughout the introduction of this technique at our medical center.Materials and methods From January 2003 to April 2004, 40 patients undergoing surgery were assigned to laparoscopic surgery group (LSG) (n=20) or conventional surgery group (CSG) (n=20). Data were prospectively collected to statistically analyze clinical, anatomopathological, and economic variables.Results Groups were comparable in age, sex, body mass index, American Society of Anesthesiologists score, surgical technique performed, tumor size and distance, Dukes’ stage, and proportion of patients with previous abdominal surgery and radiotherapy. There was no difference in operative time. LSG blood loss was lower (p<.0001). LSG peristalsis and oral intake began earlier (p<.0001). LSG hospital stay was shorter (p<.0001). Intraoperative complications (10% LSG vs 15% CSG) and overall morbidity (35% LSG vs 45% CSG) were no different. LSG did not record any anastomotic leakages. Two patients (10%) were converted to open surgery. Regarding oncologic adequacy of resection, specimen length and number of nodes harvested were no different. LSG distal and radial resection margins were greater (p<.0001; p=.03). LSG operative costs were greater (p<.0001). However, CSG hospitalization costs were higher (p<.001). There was no overall difference (p=0.1).Conclusions LSRC has been a reliable and efficient technique during the learning curve at our hospital.     

Review of 500 single incision laparoscopic colorectal surgery cases- Lessons learned

Single incision laparoscopic surgery(SILS) is a minimally invasive platform with specific benefits over traditional multiport laparoscopic surgery. The safety and feasibility of SILS has been proven, and the applications continue to grow with experience. After 500 cases at a high-volume, single-institution, we were able to standardize instrumentation and operative steps, as well as develop adaptations in technique to help overcome technical and ergonomic challenges. These technical adaptations have allowed the successful application of SILS to technically difficult patient populations, such as pelvic cases, inflammatory bowel disease cases, and high body mass index patients. This review is a frame of reference for the application and wider integration of the single incision laparoscopic platform in colorectal surgery.     

Simultaneous laparoscopic multi-organ resection combined with colorectal cancer: comparison with non-combined surgery

AIM: To access the short-term outcomes of simultaneous laparoscopic surgery combined with resection for synchronous lesions in patients with colorectal cancer.METHODS: Between March 1996 and April 2010 prospectively collected data were reviewed from 93 consecutive patients who had colorectal cancer and underwent simultaneous multiple organ resection (combined group) and 1090 patients who underwent conventional laparoscopic right hemicolectomy or laparoscopic low/anterior resection for colorectal cancer (non-combined group). In the combined group, there were nine gastric resections, three nephrectomies, nine adrenalectomies, 56 cholecystectomies, and 21 gynecologic resections. In addition, five patients underwent simultaneous laparoscopic resection for three organs. The patient demographics, intra-operative outcomes, surgical morbidity, and short-term outcomes were compared between the two groups (the combined and non-combined groups).RESULTS: There were no significant differences in the clinicopathological variables between the two groups. The operating time was significantly longer in the combined group than in the non-combined group, regardless of tumor location (laparoscopic right hemicolectomy and laparoscopic low/anterior resection groups; P = 0.048 and P < 0.001, respectively). The other intra-operative outcomes, such as the complications and open conversion rate, were similar in both groups. The rate of post-operative morbidity in the combined group was similar to the non-combined group (combined vs non-combined, 15.1% vs 13.5%, P = 0.667). Oncological safety for the colon and synchronous lesions were obtained in the combined group.CONCLUSION: Simultaneous laparoscopic multiple organ resection combined with colorectal cancer is a safe and feasible option in selected patients.     

Three-dimensional computed tomography in laparoscopic surgery for colorectal carcinoma

AIM: To evaluate the usefulness of three-dimensional computed tomography (3DCT) in laparoscopic surgery for colorectal carcinoma. METHODS: Seventy-two patients with colorectal cancer who underwent curative operation at our hospital were enrolled in this study. They were classified into two groups by operative procedures. Sixteen patients underwent laparoscopic surgery, laparoscopic group (LG), while 56 patients underwent conventional open surgery, open group (OG). At our institution, contrast-enhanced CT is routinely performed as part of intra-abdominal screening and the 3D images of the major regional vessels are described. We have previously described about the preoperative visualization of the inferior mesenteric artery (IMA) by 3DCT. This time we newly acquired 3D images of the superior mesenteric artery (SMA)/superior mesenteric vein (SMV), ileocecal artery (ICA), middle colic artery (MCA), and inferior mesenteric vein (IMV). We have compared our two study groups with regard to five items, including clinical anastomotic leakage. We have discussed here the role of 3DCT in laparoscopic surgery for colorectal carcinoma. RESULTS: The mean length of the incision in LG was 4.625+/-0.89 cm, which was significantly shorter than that in OG (P<0.001). The association between ICA and SMV and SMA was described in the right-sided colectomy. The preoperative imaging of IMA and IMV was created in the rectosigmoidectomy. There was no significant difference in anastomotic leakage between the two groups, but no patients in LG experienced anastomotic leakage. CONCLUSION: Most of the patients are satisfied with the shorter incisional length following laparoscopic surgery. Preoperative visualization of the major regional vessels may be helpful for the secure treatment of the anastomosis in laparoscopic surgery for colorectal carcinoma.     

Controversy of hand-assisted laparoscopic colorectal surgery

Laparoscopically assisted colorectal procedures are time-consuming and technically demanding and hence have a long steep learning curve. In the technical demand, surgeons need to handle a long mobile organ, the colon, and have to operate on multiple abdominal quadrants, most of the time with the need to secure multiple mesenteric vessels. Therefore, a new surgical innovation called hand-assisted laparoscopic surgery (HALS) was introduced in the mid 1990s as a useful alternative to totally laparoscopic procedures. This hybrid operation allows the surgeon to introduce the non-dominant hand into the abdominal cavity through a special hand port while maintaining the pneumoperitoneum. A hand in the abdomen can restore the tactile sensation which is usually lacking in laparoscopic procedures. It also improves the eye-to-hand coordination, allows the hand to be used for blunt dissection or retraction and also permits rapid control of unexpected bleeding. All of those factors can contribute tremendously to reducing the operative time. Moreover, this procedure is also considered as a hybrid procedure that combines the advantages of both minimally invasive and conventional open surgery. Nevertheless, the exact role of HALS in colorectal surgery has not been well defined during the advanced totally laparoscopic procedures. This article reviews the current status of hand-assisted laparoscopic colorectal surgery as a minimally invasive procedure in the era of laparoscopic surgery.     

Importance of conversion for results obtained with laparoscopic colorectal surgery

PURPOSE: The need for a conversion is a problem inherent in laparoscopic surgery. The present study points up the significance of conversion for the results obtained with laparoscopic colorectal surgery and identifies the risk factors that establish the need for conversion. METHOD: The study took the form of a multicentric, prospective, observational study within the Laparoscopic Colorectal Surgery Study Group. A total of 33 institutions in Germany, Austria, and Switzerland participated. The study period was 3.5 years. Cases were documented with the aid of a standardized questionnaire. RESULTS: Within the framework of the Laparoscopic Colorectal Surgery Study Group, a total of 1,658 patients were recruited to a multicenter study over a period of three and one-half years (from August 1, 1995 to February 1, 1999). The observed conversion rate was 5.2 percent (n=86). The patients requiring a conversion were significantly heavier (body mass index, 26.5vs. 24.9) than those undergoing pure laparoscopy. Resections of the rectum were associated with a higher risk for conversion (20.9vs. 13 percent). Intraoperative complications occurred significantly more frequently in the conversion group (27.9vs. 3.8 percent). The duration of the operation was significantly increased after conversion in a considerable proportion of the procedures performed. Postoperative morbidity (47.7vs. 26.1 percent), mortality (3.5vs. 1.5 percent), recovery time, and postoperative hospital stay were all negatively influenced by conversion, in part significantly. Institutions with experience of more than 100 laparoscopic colorectal procedures proved to have a significantly lower conversion rate than those with experience of fewer than 100 such interventions (4.3vs. 6.9 percent). CONCLUSION: Although, of itself, conversion is not considered to be a complication of laparoscopic surgery, it is true that the postoperative course after conversion is associated with appreciably poorer results in terms of morbidity, mortality, convalescence, blood transfusion requirement, and postoperative hospital stay. The importance of experience in laparoscopic surgery can be demonstrated on the basis of the conversion rates. Careful patient selection oriented to the experience of the surgeon is required if we are to keep the conversion, morbidity, and mortality rates of laparoscopic colorectal procedures as low as possible.Supported by Ethicon Endosurgery, Norderstedt, Germany, and Takeda Pharma, Aachen, Germany.     

The learning curve for colorectal stent insertion for the treatment of malignant colorectal obstruction

Background/Aims

We aimed to assess the effectiveness of self-expanding metal stent (SEMS) insertion by evaluating the learning curve in relation to the experience of an endoscopist.

Methods

We retrospectively analyzed the outcomes of 120 SEMS insertion procedures performed by one endoscopist in patients with malignant colorectal obstruction. We compared the technical and clinical success rates, complication rates, and duration of the procedures by quartiles.

Results

The mean age of the patients (76 men and 44 women) was 64.6 years. The overall technical success rate was 95.0% (114/120), and the clinical success rate was 90.0% (108/120). The median procedure duration was 16.2 minutes (range, 3.4 to 96.5 minutes). From the first to the last quartile, the technical success rates were 90.0%, 96.7%, 96.7%, and 96.7% (p=0.263), and the clinical success rates were 90.0%, 90.0%, 96.7%, and 83.3% (p=0.588), respectively. Procedure-related complications were observed in 28 patients (23.3%). The complication rates for SEMS insertion when patients were divided by quartiles were 26.7%, 23.3%, 10.0%, and 33.3% (p=0.184), respectively. Moreover, the number of stents per procedure was 1.13, 1.03, 1.00, and 1.00 (p=0.029), respectively. The median duration of SEMS insertion decreased significantly, 20.9 to 14.8 minutes after the first 30 procedures (p=0.005).

Conclusions

An experienced endoscopist was able to perform the SEMS insertion procedure easily and effectively after performing 30 SEMS insertions.     

Predictive factors for anastomotic leakage after laparoscopic colorectal surgery

Every colorectal surgeon during his or her career is faced with anastomotic leakage(AL); one of the most dreaded complications following any type of gastrointestinal anastomosis due to increased risk of morbidity, mortality, overall impact on functional and oncologic outcome and drainage on hospital resources. In order to understand and give an overview of the AL risk factors in laparoscopic colorectal surgery, we carried out a careful review of the existing literature on this topic and found several different definitions of AL which leads us to believe that the lack of a consensual, standard definition can partly explain the considerable variations in reported rates of AL in clinical studies. Colorectal leak rates have been found to vary depending on the anatomic location of the anastomosis with reported incidence rates ranging from 0 to 20%, while the laparoscopic approach to colorectal resections has not yet been associated with a significant reduction in AL incidence. As well, numerous risk factors, though identified, lack unanimous recognition amongst researchers. For example, the majority of papers describe the risk factors for left-sided anastomosis, the principal risk being male sex and lower anastomosis, while little data exists defining AL risk factors in a right colectomy. Also, gut microbioma is gaining an emerging role as potential risk factor for leakage.     

Three-dimensional computed tomography in laparoscopic surgery for coiorectal carcinoma

AIM: To evaluate the usefulness of three-dimensional computed tomography (3DCT) in laparoscopic surgery for colorectal carcinoma. METHODS: Seventy-two patients with colorectal cancer who underwent curative operation at our hospital were enrolled in this study. They were classified into two groups by operative procedures. Sixteen patients underwent laparoscopic surgery, laparoscopic group (LG), while 56 patients underwent conventional open surgery, open group (OG). At our institution, contrast-enhanced CT is routinely performed as part of intra-abdominal screening and the 3D images of the major regional vessels are described. We have previously described about the preoperative visualization of the inferior mesenteric artery (IMA) by 3DCT. This time we newly acquired 3D images of the superior mesenteric artery (SMA)/superior mesenteric vein (SMV), ileocecal artery (ICA), middle colic artery (MCA), and inferior mesenteric vein (IMV). We have compared our two study groups with regard to five items, including clinical anastomotic leakage. We have discussed here the role of 3DCT in laparoscopic surgery for colorectal carcinoma. RESULTS: The mean length of the incision in LG was 4.625±0.89 cm, which was significantly shorter than that in OG (P<0.001). The association between ICA and SMV and SMA was described in the right-sided colectomy. The preoperative imaging of IMA and IMV was created in the rectosigmoidectomy. There was no significant difference in anastomotic leakage between the two groups, but no patients in LG experienced anastomotic leakage. CONCLUSION: Most of the patients are satisfied with the shorter incisional length following laparoscopic surgery. Preoperative visualization of the major regional vessels may be helpful for the secure treatment of the anastomosis in laparoscopic surgery for colorectal carcinoma.     

Single-incision laparoscopic colorectal surgery for cancer: State of art

A number of clinical trials have demonstrated that the laparoscopic approach for colorectal cancer resection provides the same oncologic results as open surgery along with all clinical benefits of minimally invasive surgery. During the last years, a great effort has been made to research for minimizing parietal trauma, yet for cosmetic reasons and in order to further reduce surgery-related pain and morbidity. New techniques, such as natural orifice transluminal endoscopic surgery (NOTES) and single-incision laparoscopy (SIL) have been developed in order to reach the goal of “scarless” surgery. Although NOTES may seem not fully suitable or safe for advanced procedures, such as colectomies, SIL is currently regarded as the next major advance in the progress of minimally invasive surgical approaches to colorectal disease that is more feasible in generalized use. The small incision through the umbilicus allows surgeons to use familiar standard laparoscopic instruments and thus, perform even complex procedures which require extraction of large surgical specimens or intestinal anastomosis. The cosmetic result from SIL is also better because the only incision is made through the umbilicus which can hide the wound effectively after operation. However, SIL raises a number of specific new challenges compared with the laparoscopic conventional approach. A reduced capacity for triangulation, the repeated conflicts between the shafts of the instruments and the difficulties to achieve a correct exposure of the operative field are the most claimed issues. The use therefore of this new approach for complex colorectal procedures might understandingly be viewed as difficult to implement, especially for oncologic cases.     

机器人结直肠癌根治术的学习曲线

目的评估机器人结直肠癌根治术不同阶段的手术效果,探讨机器人结直肠癌根治术学习曲线问题。 方法分析2014年12月至2015年8月由同一组医师完成的75例腹腔镜结直肠癌根治术,按手术先后次序分3组（A、B、C）,每组25例,比较各组机器人安装时间、手术时间、出血量、肛门排气时间、术后住院天数、术后并发症和3站淋巴结清扫数目及其总数的差异。 结果A组机器人安装时间（38±5）min,显著长于B组（22±4）min和C组（21±2）min（P均<0.05）;A组手术时间（201±39）min,显著长于B组（160±42）min和C组（156±43）min（P均<0.05）;A组出血量（142±35）ml,显著多于B组（105±28）ml和C组（102±28）ml（P均<0.05）。3组肛门排气时间、术后住院天数、术后并发症和3站淋巴结清扫数目及其总数无显著性差异（P>0.05）。A组手术25例在4个月内完成,平均每月6.3台手术,B组和C组均在2个月内完成,平均每月12.5台手术。 结论有丰富腹腔镜结直肠癌手术经验的外科医师行机器人结直肠癌根治术的学习曲线大约为25例,手术频度为平均每月6.3例。     

Systematic review of emergent laparoscopic colorectal surgery for benign and malignant disease

Laparoscopic surgery has become well established in the management of both and malignant colorectal disease.The last decade has seen increasing numbers of surgeons trained to a high standard in minimallyinvasive surgery.However there has not been the same enthusiasm for the use of laparoscopy in emergency colorectal surgery.There is a perception that emergent surgery is technically more difficult and may lead to worse outcomes.The present review aims to provide a comprehensive and critical appraisal of the available literature on the use of laparoscopic colorectal surgery(LCS)in the emergency setting.The literature is broadly divided by the underlying pathology;that is,inflammatory bowel disease,diverticulitis and malignant obstruction.There were no randomized trials and the majority of the studies were case-matched series or comparative studies.The overall trend was that LCS is associated with shorter hospital stay,par or fewer complications but an increased operating time.Emergency LCS can be safely undertaken for both benign and malignant disease providing there is appropriate patient selection,the surgeon is adequately experienced and there are sufficient resources to allow for a potentially more complex operation.     

Total mesorectal excision for mid and low rectal cancer: laparoscopic vs robotic surgery

AIM: To compare the short- and long-term outcomes of laparoscopic and robotic surgery for middle and low rectal cancer.METHODS: This is a retrospective study on a prospectively collected database containing 111 patients who underwent minimally invasive rectal resection with total mesorectal excision(TME) with curative intent between January 2008 and December 2014(robot, n = 53; laparoscopy, n = 58). The patients all had a diagnosis of middle and low rectal adenocarcinoma with stage?Ⅰ-Ⅲ disease. The median follow-up period was 37.4 mo. Perioperative results, morbidity a pathological data were evaluated and compared. The 3-year overall survival and disease-free survival rates were calculated and compared.RESULTS: Patients were comparable in terms of preoperative and demographic parameters. The median surgery time was 192 min for laparoscopic TME(L-TME) and 342 min for robotic TME(R-TME)(P 0.001). There were no differences found in the rates of conversion to open surgery and morbidity. Thepatients who underwent laparoscopic surgery stayed in the hospital two days longer than the robotic group patients(8 d for L-TME and 6 d for R-TME, P 0.001). The pathologic evaluation showed a higher number of harvested lymph nodes in the robotic group(18 for R-TME, 11 for L-TME, P 0.001) and a shorter distal resection margin for laparoscopic patients(1.5 cm for L-TME, 2.5 cm for R-TME, P 0.001). The three-year overall survival and disease-free survival rates were similar between groups.CONCLUSION: Both L-TME and R-TME achieved acceptable clinical and oncologic outcomes. The robotic technique showed some advantages in rectal surgery that should be validated by further studies.     

Implementation of mentor-assisted colorectal endoscopic submucosal dissection in Sweden; learning curve and clinical outcomes

Objective: It’s still challenging to introduce colorectal (CR) ESD in Western countries. We assessed the feasibility of introducing and implementing CR-ESD in Sweden with hiring Japanese expert as a supervisor.

Methods: We analyzed 71 consecutive CR-ESD cases performed by two endoscopists who had no (endoscopist A (E-A)) or 20 cases (endoscopist B (E-B)) of experience in ESD. E-A performed rectal lesions while E-B performed lesions in any locations. Factors associated with failure in en bloc resection and in self-accomplishment were analyzed.

Results: Overall en bloc and R0 resection rates were 80.3% and 70.4%. Adverse event occurred in 7.0% including two perforations, two post-operative hemorrhage and one delayed perforation. Only case with delayed perforation underwent surgical treatment. Total self-accomplishment rate was 50% (10/20) for E-A, and 37.3% (19/51) for E-B. Dividing each performer’s cases into three learning phases, self-accomplishment rates increased from 42.9% to 83.3% for E-A, and from 29.4% to 70.6% for E-B, as well as en bloc resection rates from 71.4% to 100% for E-A, and from 52.9% to 94.1% for E-B. Multivariate analysis revealed that location upper than rectum, lesions with formerly taken biopsy and lesions larger than 30mm were significantly associated with en bloc resection failure.

Conclusions: Implementation of CR-ESD with hiring Japanese supervisor for certain period was safe for patients and effective for good learning curve.     

70岁以上老年人腹腔镜结直肠癌手术的安全性

目的探讨腹腔镜手术治疗70岁以上老年人结直肠肿瘤的安全性。方法回顾性总结113例腹腔镜辅助和开腹结直肠手术治疗70岁以上老年人结直肠肿瘤的经验,比较腹腔镜手术组(腹腔镜组)35例、传统开腹手术组(开腹组)78例和65岁以下腹腔镜手术组(对照组)35例的手术安全性、并发症及随访结果等情况。结果腹腔镜组、对照组无手术相关死亡患者,开腹组有2例因术后肺部感染而死亡。腹腔镜组有7例(20.0%)发生术后并发症,显著少于开腹组的33例(42.3%)(P<0.05).而与对照组的3例(8.6%)比较,差异无统计学意义。腹腔镜组术中出血、排气时间与进食半流质时间分别为(92±50)ml、(2±1)d 和(5±2)d,与开腹组(156±119)ml、(3±3)d和(6±1)d 比较,差异有统计学意义(P<0.05)。腹腔镜组与对照组手术时间、术中出血及主要并发症差异无统计学意义(P>0.05)。腹腔镜组与开腹组短期内(30个月)肿瘤局部复发、远处转移率类似,累计生存率(仅肿瘤相关死亡)分别为80.4%与82.1%,差异无统计学意义。结论腹腔镜手术治疗70岁以上老年人结直肠癌安全、有效,是治疗老年人结直肠肿瘤较好的选择方法。     

Multidimensional Analysis of Learning Curves in Laparoscopic Sigmoid Resection

PURPOSE: The number of operations to reach a plateau phase in colorectal laparoscopic surgery is still under debate. There are few publications reporting on multidimensional assessment of the learning curve, including operation time and complication and conversion rates. The purpose of this study was to define a multidimensional learning curve for sigmoid resection performed by two surgeons with experience in laparoscopic surgery. METHODS: Between 1993 and 2001 from a total of 715 laparoscopic colorectal procedures, two surgeons performed self-educated 338 sigmoid resections. Demographic data, indications for surgery, procedure performed, operation time, frequency and kind of complications, conversion rate, and days to discharge were recorded. The moving average method was used to demonstrate the change of the operation time. The cumulative sum technique was used to chart the changes in the conversion and complication rates. RESULTS: Surgeon A performed 199 and Surgeon B 139 sigmoid resections. The operation time decreased from 225 minutes to 169 minutes after approximately 90 operations for Surgeon A and from 270 minutes to 223 minutes after 110 operations for Surgeon B. Based on a decline in intraoperative complications and conversion rate, the steady state was reached after approximately 70 to 80 interventions for both surgeons. CONCLUSIONS: The assessment of a learning curve should not be limited to measurement of a decrease in operation time but should also include the conversion and complication rates. The cumulative sum technique and moving average method as proposed in this study seem appropriate to evaluate the learning curve in this clinical domain. Our findings might be especially useful for those planning training programs in laparoscopic surgery.