Learning curve in videothoracoscopic thymectomy: how many operations and in which situations?

Ergonomic Assessment of Robotic versus Thoracoscopic Thymectomy

Introduction: Robotic and thoracoscopic surgery are being increasingly adopted as minimally invasive alternatives to open sternotomy for complete thymectomy. The superior maneuverability range and three-dimensional magnified vision are potential ergonomical advantages of robotic surgery. To compare the ergonomic characteristics of robotic versus thoracoscopic thymectomy, a previously developed scoring system based on impartial findings was employed. The relationship between ergonomic scores and perioperative endpoints was also analyzed. Methods: Perioperative data of patients undergoing robotic or thoracoscopic complete thymectomy between January 2014 and December 2022 at three institutions were retrospectively retrieved. Surgical procedures were divided into four standardized surgical steps: lower-horns, upper-horns, thymic veins and peri-thymic fat dissection. Three ergonomic domains including maneuverability, exposure and instrumentation were scored as excellent(score-3), satisfactory(score-2) and unsatisfactory(score-1) by three independent reviewers. Propensity score matching (2:1) was performed, including anterior mediastinal tumors only. The primary endpoint was the total maneuverability score. Secondary endpoints included the other ergonomic domain scores, intraoperative adverse events, conversion to sternotomy, operative time, post-operative complications and residual disease. Results: A total of 68 robotic and 34 thoracoscopic thymectomies were included after propensity score matching. The robotic group had a higher total maneuverability score (p = 0.039), particularly in the peri-thymic fat dissection (p = 0.003) and peri-thymic fat exposure score (p = 0.027). Moreover, the robotic group had lower intraoperative adverse events (p = 0.02). No differences were found in residual disease. Conclusions: Robotic thymectomy has shown better ergonomic maneuverability compared to thoracoscopy, leading to fewer intraoperative adverse events and comparable early oncological results.

Factors predicting perioperative outcomes in patients with myasthenia gravis or thymic neoplasms undergoing thymectomy by video-assisted thoracoscopic approach

Background:

The purpose of this study was to identify the factors which predict the perioperative outcomes after video-assisted thoracoscopic surgery (VATS) thymectomy in patients with myasthenia gravis (MG) or thymic neoplasms

Patients and Methods:

Data of consecutive patients who had undergone VATS thymectomy in our institution from August 2016 to April 2018 were collected retrospectively from a prospectively maintained database followed by prospective recruitment of patients who underwent VATS thymectomy from April 2018 to February 2020.

Results:

A total of 31 patients were included. Females were more common (51.6%), and 29 patients (93.5%) had MG. The most common indication for thymectomy was the presence of both MG and thymoma (51.6%). Most MG patients had moderate disease (55.2%) or severe (24.1%) disease preoperatively. Mean operative time and blood loss were 196.9 ± 63.5 min and 122.5 ± 115.3 ml, respectively. Mean hospital stay was 7.9 ± 6.7 days. The rate of major and minor complications was 16.18% and 35.4%, respectively. Multivariate linear regression analysis established that MG symptoms >12 months, prolonged invasive ventilation (intubation ≥24 h), and complications were associated significantly with a prolonged hospital stay. Adjusting for outliers, pre-operative disease severity (MG Foundation of America class), and intubation ≥24 h were the only factors that had a significant impact on perioperative outcomes.

Conclusion:

Pre-operative disease severity and post-operative invasive ventilation are strong determinants of perioperative outcomes. Pre-operative optimisation and early extubation protocols can further reduce morbidity in patients undergoing thymectomy by the VATS approach.

An interdisciplinary team-training protocol for robotic gynecologic surgery improves operating time and costs: analysis of a 4-year experience in a university hospital setting

Main aim of this study is to assess the effect of a structured, interdisciplinary, surgical, team-training protocol in robotic gynecologic surgery, with the gradual integration of an advanced nurse practitioner. Data from all robotic surgical procedures were prospectively acquired. The surgical team consisted of one experienced surgeon and two surgical fellows and the scrub nurse team from three advance nurse practitioners, specialized in robotic surgery. The training was performed in a four-phase manner over 4 years and included theoretical training, hands-on training and team-communication skills enhancement. Scrub nurses increasingly adopted an active role during surgery. For a period of 4 years, 175 patients could be included in the analysis. All of them underwent a robotic gynecologic procedure. Mean docking time decreased from 45.3 to 27.3 min (p < 0.001), mean operating time from 235 to 179 min (p = 0.0071) and costs per case from 17,891 to 14,731 Swiss Francs (p = 0.035). There were no statistically significant changes in perioperative complications and conversions to laparotomy. An interdisciplinary long-term training protocol for high specialized robotic surgery within a “fixed” team with the gradually addition of an advanced study nurse improves the efficacy of the procedure in terms of time and costs. Although the surgery is performed quicker, the same performance and quality of surgical care could be reached.

Early outcomes in 147 consecutive cases of subxiphoid single-port thymectomy and evaluation of learning curves

OBJECTIVES

The aim of the present study was to examine some initial results and learning curves concerning subxiphoid single-port thymectomy (SSPT), thereby clarifying the safety of this surgical approach and describing the precautions for adopting it.

METHODS

From March 2011 to August 2019, a total of 203 patients underwent thymectomy for either anterior mediastinal tumours or myasthenia gravis at Fujita Health University Hospital. Of these 203 patients, 147 patients who had undergone SSPT were selected as participants for the present study.

RESULTS

Of the 147 cases, transition to a different approach was required in three (2.0%) cases: two (1.3%) cases transitioned to median sternotomy, whereas one (0.7%) case transitioned to the side chest trans-intercostal approach. The two cases that transitioned to median sternotomy were the second cases for different operators after they began performing this technique. There were six (4.0%) cases with complications and no deaths. The operation time cumulative summation learning curve analysis revealed that the curves descended from the 38th case. In the 83 cases handled by one surgeon, the learning curves descended from the 31st case.

CONCLUSIONS

SSPT is a safe modality with few complications and no associated cases of mortality reported. Operators are required to experience 31-38 cases until the operation time for SSPT was stabilized. Special care should be exercised to prevent vascular damage in the vicinity of the innominate veins during the early stages after SSPT introduction.

Robotic-Extended Rethymectomy for Refractory Myasthenia Gravis: A Case Series

To assess the safety and efficacy of robotic-extended rethymectomy in selected refractory myasthenia gravis (MG) patients with suspected residual thymic tissue. Robotic-extended rethymectomy was performed in 6 MG patients with seropositive acetylcholine receptors (AChR) antibody who had undergone a previous thymectomy (1 cervicotomy, 2 video-assisted thoracoscopic surgeries, and 3 sternotomies). The median observation time before robotic rethymectomy was 108 (24-171) months. The main outcomes were perioperative morbidity, mortality, conversion to open surgery, and clinical outcomes according to the Myasthenia Gravis Foundation of America Post-Intervention Status (MGFA-PIS). Before rethymectomy, all patients required immunosuppressants and 5 patients (83.3%) required intravenous immune globulin and/or plasma exchange to control the symptoms. The median specimen weight was 24.5 (14-144) g after rethymectomy, and residual thymic tissue was found in 5 patients (83.3%). No conversion to open surgery or perioperative morbidity and mortality was observed. With a median follow-up time of 46.5 (13-155) months, 3 patients (50%) achieved "improved" and 3 (50%) were "unchanged" according to the MGFA-PIS. Compared with preoperative use, the median daily dose of corticosteroids statistically decreased (25 [7.5-60] vs 0 [0-5] mg, P = 0.002) without significant change in azathioprine use (100 [0-200] vs 50 [0-150] mg, P = 0.360). AChR antibody positive MG patients with a treatment refractory long-term course after thymectomy might have remaining thymic tissue with the 2 commonly associated thymus pathologies, thymoma, and follicular hyperplasia. Robotic-extended rethymectomy might be considered as a safe and beneficial treatment option in these patients.

Successful Sleeve Resection as a Marker for Proficiency for Robotic Pulmonary Resection

BACKGROUND

 Robot technology is a revolutionary technique to overcome limitations of minimal invasive surgery. The proficiency level varies from study to study. We considered the first sleeve lobectomy as a benchmark procedure to evaluate the proficiency level.

METHODS

 We retrospectively analyzed 197 patients who underwent robot-assisted thoracoscopic surgery (RATS) for primary lung cancer between December 2011 and May 2018. Patients were divided into two groups based on undergoing surgery earlier period (EP) or later period (LP) than the first sleeve lobectomy by RATS (May 25, 2015). The preoperative, operative, and short- and long-term postoperative outcomes were compared. Seven-year survival was also compared between two periods for T1N0 and T2N0 diseases.

RESULTS

 Preoperative features were similar. The mean operative time was 166.8 ± 55.1 and 142.4 ± 43.9 minutes in EP and LP, respectively (p = 0.005). The mean number of dissected lymph nodes in LP was also significantly higher than that in EP (24.4 ± 9.4 vs. 20.8 ± 10.4, p = 0.035). The complication rate was significantly lower in LP (29/86 vs. 25/111, p = 0.048). The extended resection (ER) rate was significantly higher in LP (p = 0.023). The 7-year survival was comparable in EP and LP in both patients with T1N0 and T2N0 (p = 0.28 and p = 0.11, respectively).

CONCLUSION

 Perioperative outcomes, such as duration of surgery, number of dissected lymph nodes, complications, and ERs are favorable in patients who underwent surgeries after the first sleeve resection. The first sleeve lobectomy may be considered as the benchmark procedure for the proficiency level in RATS.

The resident's point of view in the learning curve of thymic MIS: why should I learn it?

Minimally invasive surgery (MIS) in thoracic surgery became quite popular during the last years. The aim of introducing and performing more MIS is to reduce surgical trauma, pain and complications in patients. Training in MIS increases operative time and thus cost in theatre but thus improves with experience. For a resident, the cases should be well selected with experienced supervision in a suitable setting with supporting staff and optimal instruments. Understanding the anatomy of the lung, using simulators, and attending workshops makes the learning curve shorter.

Thoracoscopic Thymectomy Using a Subxiphoid Approach for Anterior Mediastinal Tumors

PURPOSE

Video-assisted thoracic surgery (VATS) techniques have been widely used for resection of mediastinal tumors. This study investigated the usefulness of the subxiphoid approach in thoracoscopic thymectomy.

METHODS

In all, 36 patients with anterior mediastinal tumor underwent thymectomy using the subxiphoid approach in two Japanese institutions. These patients were retrospectively reviewed and analyzed.

RESULTS

There were 16 females and 20 males with a mean age of 57 years. Five patients underwent partial thymectomy (PT), 27 underwent total or subtotal thymectomy, and 4 underwent thymectomy with combined resection (CR) of the surrounding organs or tissues. The mean maximum tumor diameter, amount of resected tissue, and blood loss were 4.1 cm, 72.5 g, and 20.6 g, respectively. More than half of tumors were diagnosed as thymoma (n = 19). The operation time was prolonged with a greater volume of thymectomy. The duration of chest tube drainage and postoperative stay were 1.7 ± 1.0 days and 5.9 ± 7.6 days, respectively. Four patients suffered intraoperative and postoperative complications, as follows: bleeding of the innominate vein, bleeding of the internal thoracic vein, crisis of myasthenia gravis (MG), pericarditis, and phrenic nerve paralysis. There were no mortalities after surgery.

CONCLUSION

Subxiphoid thoracoscopic thymectomy might be a safe and useful approach for mediastinal tumors.

What happens while learning robotic lobectomy for lung cancer?

A surgeon needs to perform a sufficient number of procedures to achieve a level of proficiency. Learning curves demonstrate ongoing improvement in efficiency over the course of a surgeon's carrier. When the surgeon learns the procedure, this means that he has the ability to perform that procedure safely and effectively. The instruction of the da Vinci Surgical System (Initiative Surgical, Sunnyvale, CA, USA) provoked the need for preparing surgeons for complex robotic skills. As low as 5 repetitions are enough to achieve proficiency on basic robotic skills. Robotic-assisted thoracic surgery (RATS) has a steep learning curve compared to video-assisted thoracic surgery (VATS), and it was proposed that 15 to 20 operations are required to establish a learning curve for RATS anatomical pulmonary resections. Based on several studies, one can conclude that after learning, there is a tendency to toward shorter operative times, a decrease in conversion, morbidity and mortality rates, as well as an increase in the number of resected lymph nodes. Our clinical experience on 129 patients undergoing RATS anatomic pulmonary resections over a period of 5-year demonstrated that the learning curve could be established after 14^th operation, and the acquired surgical skills and developing experience let surgeon to obtain shorter operative times, operate larger tumors with more advanced stages, have an increased the number of the dissected lymph nodes.

Cusum analysis for learning curve of videothoracoscopic lobectomy

Background

Video assisted thoracoscopic (VATS) lobectomy has a demanding learning curve due to its technical complexity and risk of uncontrollable bleeding. We investigated the case number required for gaining technical proficiency by applying cumulative sum analysis on initial VATS lobectomy operations of a single surgeon.

Methods

CALGB definition was used for the definition of VATS lobectomy. The data of the initial cases evaluated and cumulative sum (CUSUM) analysis was applied to duration of the operations and length of hospital stay.

Results

Fifty-eight patients underwent VATS lobectomy. Of those 51 were malignant and 7 were benign. Fifty-five of the procedures were lobectomy, 2 were inferior bi-lobectomy and 1 was left upper lobectomy with chest wall resection. CUSUM analysis reached to proficiency at 27 cases for duration of the operations.

Conclusions

The length of learning curve depends on previous experience of the surgeon on open lobectomy and simpler VATS operations, potential number of VATS lobectomy cases and VATS capability of the surgeon. Depending on these factors, it is possible to obtain technical proficiency with an inferior number of procedures compared with existing literature (50-200).

Video-assisted thoracoscopic lobectomy: which is the learning curve of an experienced consultant?

BACKGROUND

This study evaluates the number of video-assisted thoracic surgery-lobectomies (VATS-lobectomies) required for an experienced consultant thoracic surgeon to obtain competence and to perform standard quality surgery.

METHODS

We have analysed the initial VATS-experience (January 2012 to September 2014) of a confirmed senior consultant who has performed 145 consecutive anatomic resections by thoracoscopy. After excluding bilobectomies, segmentectomies, and lobectomies for infectious disease, we have focused into 119 consecutive lobectomies, classified into 4 chronologic groups of 30 each. We have considered: demographics; pathology; postoperative outcomes; conversion rate; morbidity. We compared the 4 groups in a Bayesian inference model (very strong probability of a difference if Pr>95% or <5%; strong probability if 95%>Pr>80% or 5%<Pr<20%).

RESULTS

There was a very strong probability of difference of group 1 (first 30 lobectomies) compared to the 3 other groups: less incomplete fissures (Pr_1<2=0.019, Pr_1<3=0.037, Pr_1<4=0.046), more node samplings (Pr_1>2=0.977, Pr_1>3=0.96, Pr_1>4=0.997) and, conversely, less radical dissections (Pr_1<2=0.022, Pr_1<3=0.039, Pr_1<4=0.003), less harvested nodes (Pr_1<2≤0.001, Pr_1<3≤0.001, Pr_1<4≤0.001), less pleural adhesions (Pr_1<2=0.077, Pr_1<3=0.044). Instead, there was a very strong probability of difference of group 4 compared to the first three groups (first 90 lobectomies): lower conversion rate (Pr_1>4=0.992, Pr_3>4=0.996, Pr_2>4=0.995), lower duration of the operation (Pr_1>4=0.946, Pr_2>4=0.901, Pr_3>4=0.932), less air leak (Pr_1>4=0.936, Pr_2>4=0.97) and shorter chest tube drainage (Pr_1>4=0.94, Pr_2>4=0.94, Pr_3>4=0.937), as well as shorter hospital stay (Pr_2>4=0.94, Pr_3>4=0.937).

CONCLUSIONS

The learning curve was bimodal. After the initial 30 lobectomies, oncologic quality of the procedure improved and stabilized. The surgeon became less selective and accepted to proceed with more complex cases (incomplete fissures, pleural adhesions). Efficiency was obtained after 90 lobectomies (shorter operative time and lower conversion rate).

Thoracoscopic Vertebrectomy for Thoracolumbar Junction Fractures and Tumors: Surgical Technique and Evaluation of the Learning Curve

STUDY DESIGN

Retrospective study.

OBJECTIVE

The authors evaluated the surgical technique and learning curve for video-assisted thoracoscopic surgery (VATS) for treating thoracolumbar junction burst fractures and bony tumors by examining surgical data and outcome for the first 30 VATS procedures performed by a single surgeon at a training institution.

SUMMARY OF BACKGROUND DATA

VATS is commonly used in the treatment of early-stage lung cancer. Widespread use of this technique among neurosurgeons is limited by the lack of cases and the steep learning curve.

METHODS

This study was a retrospective case series of the first 30 T12 and L1 thoracoscopic vertebrectomies from 2003 to 2008. The sample was limited to 1 surgeon and 1 region of the spine to minimize the potential variation so that a learning curve could be assessed. Surgical data and outcomes were analyzed. Estimated blood loss and operation time were analyzed using a linear generalized estimating equation model with a first-order autoregression correlation structure.

RESULTS

The average operative time for thoracoscopic corpectomy was 270±65 minutes (range, 160-416 min). Operating room time decreased significantly after the first 3 operations. The authors observed a stable linear decrease in operating time over the course of the study. The average blood loss during the thoracoscopic procedure was 433±330 mL (range, 100-1500 mL) and did not change as the series progressed. Complications and conversions to open procedures occurred in 2 patients and were evenly distributed throughout the series.

CONCLUSIONS

Thoracoscopic vertebrectomy at the thoracolumbar junction has a relatively long learning curve. In this series, operating room time improved dramatically after the first 3 cases but continued to improve subsequently. The learning curve can be accomplished without an increase in blood loss, complications, rate of conversion to open procedures, or frequency of misplaced instrumentation.

Catastrophes during video-assisted thoracoscopic thymus surgery for myasthenia gravis

OBJECTIVES

Several series have demonstrated that video-assisted thoracoscopic (VAT) thymectomy is feasible and safe. However, VAT thymectomy is an operation that could invite catastrophes, such as major vascular injuries. We aimed to analyse the events and define the management and outcomes of these serious complications.

METHODS

All patients who underwent VAT thymectomy/thymothymectomy recorded in our clinical database were evaluated. A catastrophic complication was defined as any situation that resulted in an additional unplanned major surgical procedure other than the planned closed thymic surgery. Operations were performed by two surgeons: one experienced and one junior. The order of catastrophes in each surgeon's experience was recorded.

RESULTS

A total of 441 VAT thymectomy/thymothymectomy operations were performed. Catastrophic complications were identified in 7 (1.5%) patients. These cases included 3 major innominate vein injuries, 1 superior vena cava injury, 1 aortic injury, 1 sudden cardiac arrest and 1 diaphragmatic injury. The first catastrophe for the experienced surgeon was his 96th case. The mean age was 37.1 ± 11.5 (minimum: 21, maximum: 53). There were 5 (71.4%) male and 2 (28.6%) female patients. Two (28.6%) of the patients had thymoma and the mean body mass index was 23.9 ± 2.8. A mean of 1.7 ± 1.4 (minimum: 0, maximum: 3) units of blood were transfused; a postoperative intensive care unit stay of 20.6 ± 25.7 h and a hospital stay of 8.4 ± 7.9 days were recorded. There were no deaths.

CONCLUSIONS

Catastrophic intraoperative complications of VAT thymectomy are very rare. They may not only occur in the learning curve period but also after a large experience. Experience in converting to open surgery within seconds is important to reduce morbidity and mortality.

Attaining proficiency with endobronchial ultrasound-guided transbronchial needle aspiration

OBJECTIVES

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is becoming the preferred method of mediastinal staging for lung cancer. We investigated the learning curve for EBUS-TBNA using risk-adjusted cumulative sum (Cusum).

METHODS

A retrospective study of EBUS-TBNA was performed at a single academic institution for patients with mediastinal or hilar lymphadenopathy in the setting of proven or suspected lung cancer. A sampling pass was defined as a full retraction and repositioning of the aspiration needle. Rapid on-site evaluation was not available. To track proficiency, risk-adjusted Cusum analysis was performed using acceptable and unacceptable failure rates of 10% and 20%, respectively. Failure was defined as false negative or nondiagnostic results.

RESULTS

During the study period, 231 patients underwent EBUS-TBNA. Prevalence of mediastinal or hilar malignancy was 66.7% (154 out of 231). Sensitivity was 92.2% (142 out of 154), and negative predictive value was 87.9% (58 out of 66). Node size was identified as a significant predictor of EBUS-TBNA success by multiple regression. Risk-adjusted Cusum analysis demonstrated that the first and only unacceptable decision interval was crossed at 22 cases. Individual practitioner learning curves were highly variable, and the operator with the highest volume was the most consistently proficient.

CONCLUSIONS

In our experience, attainment of an acceptable failure rate for EBUS-TBNA required 22 cases. Node size is a predictor of EBUS-TBNA success. Risk-adjusted Cusum proved a powerful evaluative tool to monitor the training process of this new procedure.

Application of video-assisted thoracic surgery in the standard operation for thoracic tumors

OBJECTIVE

To evaluate the short-term outcomes of video-assisted thoracic surgery (VATS) for thoracic tumors.

METHODS

The data of 1,790 consecutive patients were retrospectively reviewed. These patients underwent VATS pulmonary resections, VATS esophagectomies, and VATS resections of mediastinal tumors or biopsies at the Cancer Institute & Hospital, Chinese Academy of Medical Sciences between January 2009 and January 2012.

RESULTS

There were 33 patients converted to open thoracotomy (OT, 1.84%). The overall morbidity and mortality rate was 2.79% (50/1790) and 0.28% (5/1790), respectively. The overall hospitalization and chest tube duration were shorter in the VATS lobectomy group (n=949) than in the open thoracotomy (OT) lobectomy group (n=753). There were no significant differences in morbidity rate, mortality rate and operation time between the two groups. In the esophageal cancer patients, no significant difference was found in the number of nodal dissection, chest tube duration, morbidity rate, mortality rate, and hospital length of stay between the VATS esophagectomy group (n=81) and open esophagectomy group (n=81). However, the operation time was longer in the VATS esophagectomy group. In the thymoma patients, there was no significant difference in the chest tube duration, morbidity rate, mortality rate, and hospital length of stay between the VATS thymectomy group (n=41) and open thymectomy group (n=41). However, the operation time was longer in the VATS group. The median tumor size in the VATS thymectomy group was comparable with that in the OT group.

CONCLUSIONS

In early-stage (I/II) non-small cell lung cancer patients who underwent lobectomies, VATS is comparable with the OT approach with similar short-term outcomes. In patients with resectable esophageal cancer, VATS esophagectomy is comparable with OT esophagectomy with similar morbidity and mortality. VATS thymectomy for Masaoka stage I and II thymoma is feasible and safe, and tumor size is not contraindicated. Longer follow-ups are needed to determine the oncologic equivalency of VATS lobectomy, esophagectomy, and thymectomy for thymoma vs. OT.

Unilateral extended thoracoscopic thymectomy for nontumoral myasthenia gravis--a new standard

Myasthenia gravis (MG) is a heterogeneous disorder with a fluctuating, clinical, pathologic, and immunobiological picture. Today, it is believed that effective treatment of MG must include both immunosuppression and surgery. Thymectomy is recommended by neurologists for patients with nontumoral MG as an option to increase the probability of remission or improvement. Currently, thoracoscopic thymectomy is considered a good alternative to the standard open approach because of its higher rate of acceptance, low morbidity, and high efficacy, as measured by complete stable remission rates. We present a review of the experience of unilateral extended thoracoscopic thymectomy for nontumoral MG, a technique that could became a new standard in the complex management of MG treatment.

Surgeons' volume-outcome relationship for lobectomies and wedge resections for cancer using video-assisted thoracoscopic techniques

This study examined the effect of surgeons' volume on outcomes in lung surgery: lobectomies and wedge resections. Additionally, the effect of video-assisted thoracoscopic surgery (VATS) on cost, utilization, and adverse events was analyzed. The Premier Hospital Database was the data source for this analysis. Eligible patients were those of any age undergoing lobectomy or wedge resection using VATS for cancer treatment. Volume was represented by the aggregate experience level of the surgeon in a six-month window before each surgery. A positive volume-outcome relationship was found with some notable features. The relationship is stronger for cost and utilization outcomes than for adverse events; for thoracic surgeons as opposed to other surgeons; for VATS lobectomies rather than VATS wedge resections. While there was a reduction in cost and resource utilization with greater experience in VATS, these outcomes were not associated with greater experience in open procedures.

Experience with Robotic Lobectomy for Lung Cancer

Objective

In this study, we analyze our experience so far with robotic pulmonary lobectomy, compare it with published data, and suggest a learning curve for the operation.

Methods

Ninety-one patients with suspected or proven clinical stage I–III lung cancer underwent robotic lobectomy. Selection criteria included lesion ≤5 cm and normal respiratory function. One surgeon performed the operations using the da Vinci system with three ports and a 3-cm utility thoracotomy.

Results

Median duration of operation was 239 (range 85–411) minutes, 260 minutes in the first 18 patients and 221 minutes in the remaining 73 cases (P = 0.01). Median hospitalization declined from 6 days in the first 18 cases to 5 days in the remaining cases (P = 0.002). Conversion rate and number of complications reduced nonsignificantly from the initial to later series. Major complications occurred in 11% of the first 18 cases and 4% of the later cases. The number of lymph nodes removed did not change over the two series. There was no 30-day postoperative mortality. After a median follow-up of 24 months, 80 of 91 patients were alive with no sign of disease.

Conclusions

Our data suggest that about 20 operations are required to achieve surgical competence. Robotic lobectomy appears safe, oncologically radical, and associated with shorter postoperative hospitalization than open surgery.

Learning curve for Doppler measurement of fetal modified myocardial performance index

OBJECTIVE

To assess the learning curve for measurement of the fetal modified myocardial performance index (MPI).

METHODS

Three trainees with the theoretical knowledge of but without prior experience in performing MPI measurement were selected. Each trainee and one experienced examiner measured MPI in a cohort of 90 consecutive fetuses. The average difference between the three trainees and the expert in the MPI measurements was calculated; a difference below 10% was considered to indicate an accurate measurement. Individual and averaged learning curves were delineated using cumulative sum analysis (CUSUM).

RESULTS

The gestational age at evaluation ranged from 20 + 4 to 41 + 4 (mean, 33 + 3) weeks. The CUSUM plots demonstrated that, on average, competence in performing fetal MPI measurement was achieved by 65 cases. The average number of attempts to achieve competence were 42, 77 and 83 for the ejection time, isovolumetric contraction time and isovolumetric relaxation time, respectively.

CONCLUSIONS

Evaluation of fetal MPI by an inexperienced trainee requires on average 65 measurements to achieve competence.

Does a relationship exist between the number of thoracoscopic thymectomies performed and the learning curve for thoracoscopic resection of thymoma in patients with myasthenia gravis?

This study aimed to analyze surgeons' learning curve for thymoma resection with video-assisted thoracoscopic surgery (VATS). Two hundred and eleven myasthenia gravis patients had VATS thymic resections, including 25 patients with a thymoma. Three groups of surgeries, according to the order of operations, were analyzed: Group A comprised the first 70 thymectomies, Group B comprised the second 70 thymectomies, and Group C comprised the final 71 thymectomies. We compared the groups on a set of preoperative (age, gender, body mass index, and Osserman stage), operative (number in each group, size, and Masaoka stage), and postoperative (complications and length of stay) variables. A significant difference was observed in the number of thymoma operations (Group A: four patients, Group B: seven patients, and Group C: 14 patients; P: 0.031) and the duration of operation (Group A: 66 min, Group B: 52 min, and Group C: 48 min; P: 0.024). A strong correlation was found between the duration of operation and order of patients (Pearson r: -0.554, P: 0.000). We recommend the start of a program for the resection of thymoma with VATS after surgical staff have performed 70 VATS thymectomy operations.

Learning curve for lung area to head circumference ratio measurement in fetuses with congenital diaphragmatic hernia

OBJECTIVE

To assess the learning curve for the fetal lung area to head circumference ratio (LHR) calculation in fetuses with congenital diaphragmatic hernia (CDH).

METHODS

Three trainees with the theoretical knowledge, but without prior experience in the LHR measurement, were selected. Each trainee and one experienced examiner measured the observed to expected (O/E)-LHR in the lung contralateral to the side of the hernia by two methods-manual tracing of lung borders and multiplication of the longest diameters-in a cohort of 95 consecutive CDH fetuses. The average difference between the three trainees and the expert in the O/E-LHR measurement was calculated. A difference below 10% was considered to indicate an accurate measurement. The average learning curve was delineated using cumulative sum analysis (CUSUM).

RESULTS

The CUSUM plots demonstrate that the learning curve was achieved by 77 and 72 tests performed for the area obtained by the manual-tracing and multiplication-of-the-longest-diameter methods, respectively.

CONCLUSION

The minimum number of scans required for an inexperienced trainee to become competent in examining the LHR is on average 70.