Analysis of the learning curve in telerobotic, beating heart coronary artery bypass grafting: a 90 patient experience

The first year is the hardest: a comparison of early versus late experience after the introduction of robotic hiatal hernia repair

While the majority of the literature written concerning minimally invasive hiatal hernia repair involves laparoscopy, little has been written concerning the transition to a robotic technique. We present our experience, with a transparent analysis of data, with regard to the introduction of robotic paraesophageal hernia (PEH) repair by an experienced laparoscopic surgeon. We reviewed our first 30 consecutive patients who underwent robotic PEH over a 2-year period after the introduction of robotic surgery at our institution. Patients were divided into two groups: the early experience group (procedures performed within the first year of introduction of robotic technique, n = 13) and a late experience group (procedures performed in the second year, n = 17). All procedures were performed by a single experienced foregut surgeon. The mean operative time for the early group was significantly greater than for the late group, 184 min versus 142 min, respectively (p < 0.01). Four patients in the early group required conversion to open, while zero patients in the late group required conversion (p = 0.03). Patient demographics and complications did not differ significantly between the two patient populations. The early robotic hiatal hernia repair experience can be more difficult than expected, even in the hands of an experienced laparoscopic team. We identify several areas of improvement including patient positioning, operating room team training, and technical experience. This data can help other surgeons prepare for the transition to robotic foregut surgery.

Robotic-assisted coronary artery bypass surgery: an 18-year single-centre experience

BACKGROUND

Minimally invasive robot-assisted direct coronary artery bypass (RADCAB) has emerged as a feasible minimally invasive surgical technique for revascularization that might offer several potential advantages over conventional approaches. We present our 18-year experience in RADCAB.

METHODS

Between February 1998 and February 2016, 605 patients underwent RADCAB. Patients underwent post-procedural selective graft patency assessment using cardiac catheterization.

RESULTS

The mortality rate was 0.3%. The rate of conversion to sternotomy for any cause was reduced from 16.0% of the first 200 cases to 6.9% of the last 405 patients. The patency rate of the LITA-to-LAD anastomosis was 97.4%. Surgical re-exploration for bleeding occurred in 1.8% of patients, and the transfusion rate was 9.2%. Average ICU stay was 1.2 ± 1.4 days, and average hospital stay was 4.8 ± 2.9 days.

CONCLUSIONS

Robot-assisted coronary artery bypass grafting is safe, feasible and it seems to represent an effective alternative to traditional coronary artery bypass grafting in selected patients.

A systematic review on robotic coronary artery bypass graft surgery

BACKGROUND

Robotic-assisted coronary artery bypass graft surgery (CABG) has been performed over the past decade. Despite encouraging results from selected centres, there is a paucity of robust clinical data to establish its clinical safety and efficacy. The present systematic review aimed to identify all relevant clinical data on robotic CABG. The primary endpoint was perioperative mortality, and secondary endpoints included perioperative morbidities, anastomotic complications, and long-term survival.

METHODS

Electronic searches were performed using three online databases from their dates of inception to 2016. Relevant studies fulfilling the predefined search criteria were categorized according to surgical techniques as (I) totally endoscopic coronary artery bypass without cardiopulmonary bypass (TECAB off-pump); (II) TECAB on-pump; and robotic-assisted mammary artery harvesting followed by minimally invasive direct coronary artery bypass (robotic MIDCAB).

RESULTS

The present systematic review identified 44 studies that fulfilled the study selection criteria, including nine studies in the TECAB off-pump group and 16 studies in the robotic MIDCAB group. Statistical analysis reported a pooled mortality of 1.7% for the TECAB off-pump group and 1.0% for the robotic MIDCAB group. Intraoperative details such as the number and location of grafts performed, operative times and conversion rates, as well as postoperative secondary endpoints such as morbidities, anastomotic complications and long-term outcomes were also summarized for both techniques.

CONCLUSIONS

A number of technical, logistic and cost-related issues continue to hinder the popularization of the robotic CABG procedure. Current clinical evidence is limited by a lack of randomized controlled trials, heterogeneous definition of techniques and complications, as well as a lack of robust clinical follow-up with routine angiography. Nonetheless, the present systematic review reported acceptable perioperative mortality rates for selected patients at specialized centres. These results should be considered as a useful benchmark for future studies, until further data is reported in the form of randomized trials.

Enhancing quality control and performance monitoring in thoracic aortic surgery: a 10-year single institutional experience

OBJECTIVES

The aim of the present study was to monitor performance and learning effects for thoracic aortic surgery. In addition, we evaluated the volume-outcome relationship of patients undergoing surgery of the thoracic aorta, comparing the results of two higher-volume surgeons (HVSs) with six lower volume surgeons.

METHODS

A total of 867 thoracic aortic procedures (elective cases n = 753 and Type A acute dissection n = 114) were performed from 2003 to 2013 by eight surgeons (range 28-238 procedures) at our institution. Departmental and individual performance was monitored using control charts, with a predetermined acceptable failure rate of 10%. Perioperative death or one or more of four adverse events constituted failure. Moreover, results of two higher-volume operators (n = 460; 53%) were compared with those of six lower-volume operators (n = 407; 47%).

RESULTS

The incidence rate of in-hospital mortality for elective cases was 2% and for Type A dissection repair 9.6%. Institutional control charts revealed that the surgical process was under control for all the study periods apart from small periods of worse than expected performance which were congruent with new surgeons joining the programme. The predominant surgical failure was reoperation for bleeding. There were differences between surgeons with regard to the learning curves and performance. No significant differences were observed between high- and low-volume surgeons in terms of mortality and morbidity for elective cases. However, high-volume surgeons presented a trend suggesting a higher mortality rate in Type A aortic dissection repair (17.1 vs 6.3%; P = 0.09).

CONCLUSIONS

Thoracic aortic surgery can be performed with similar results by high- and low-volume surgeon. Control charts can facilitate learning effects and performance monitoring. Implementation of continuous departmental and individual performance monitoring is practicable.

Defining the Learning Curve for Robotic-Assisted Endoscopic Harvesting of the Left Internal Mammary Artery

Objective

Robotic-assisted techniques are continuing to cement their role in coronary surgery, particularly in facilitating the endoscopic harvesting of the left internal mammary artery (LIMA), regardless of how the subsequent bypass grafting is performed. As more surgeons attempt to become trained in robotic-assisted procedures, we sought to better define the learning curve associated with robotic-assisted endoscopic LIMA harvest.

Methods

Between January 2011 and July 2012, a total of 77 patients underwent robotic-assisted minimally invasive direct coronary artery bypass surgery at our institution. The LIMA was harvested endoscopically in all patients, using standard robotic instruments, followed by direct grafting to anterior wall myocardial vessels via a small thoracotomy. Intraoperative times for various components of the procedure were collated and analyzed.

Results

The mean ± SD time taken to insert and position the ports for the robotic instruments was 3.9 ± 1.4 minutes. The mean ± SD LIMA harvest time was 31.8 ± 10.1 minutes, and the mean ± SD total robotic time was 44.2 ± 12.9 minutes. All time variables consistently continued to decrease as the experience of the operating surgeon increased, with the greatest magnitude of improvement being evident within the first 20 cases. The logarithmic learning curves for LIMA harvest time and total robot time during our entire experience were both calculated as 90%, correlating to an expected 10% improvement in performance for each doubling of cases completed.

Conclusions

Coronary surgeons can rapidly become proficient in robotic-assisted endoscopic LIMA harvest, with significant improvement in operative times evident within the first 20 cases completed. These data may be useful in designing appropriate training programs for newer surgeons seeking to gain experience in robotic-assisted coronary surgery.

IDEAL framework for surgical innovation 2: observational studies in the exploration and assessment stages

The IDEAL framework describes the stages of evaluation for surgical innovations. This paper considers the role of observational studies in the exploration and assessment stages. At the exploration stage, the surgical intervention is usually more widely used, and observational studies should collect prospective data from multiple surgeons, deal with factors such as case mix and learning, and prepare for a definitive evaluation at the next stage of assessment. Although a randomised controlled trial is preferable, a high quality observational study would be acceptable if a randomised trial is not feasible or, on rare occasions, deemed unnecessary.

The multiphasic learning curve for robot-assisted rectal surgery

BACKGROUND

Robotic rectal surgery is gaining in popularity. We aimed to define the learning curve of an experienced laparoscopic colorectal surgeon in performing robot-assisted rectal surgery. We hypothesized that there are multiple phases in this learning process.

METHODS

We performed a retrospective analysis. Consecutive patients who underwent robot-assisted rectal surgery between July 2007 and August 2011 were identified. Operating times were analyzed using the CUSUM (cumulative sum) technique. CUSUMs were model fitted as a fourth-order polynomial. χ(2), Fisher's exact, two independent samples t test, one-way ANOVA, Kruskal-Wallis, and Mann-Whitney tests were used. A p value of <0.05 was considered statistically significant.

RESULTS

We identified 197 patients. The median (range) total operative, robot, console, and docking times (min) were 265 (145-515), 140 (59-367), 135 (50-360), and 5 (3-40), respectively. CUSUM analysis of docking time showed a learning curve of 35 cases. CUSUM analysis of total operative, robot, and console times demonstrated three phases. The first phase (35 patients) represented the initial learning curve. The second phase (93 patients) involved more challenging cases with increased operative time. The third phase (69 patients) represented the concluding phase in the learning curve. There was increased complexity of cases in the latter two phases. Of phase 1 patients, 45.7% had tumors ≤7 cm from the anal verge compared to 64.2% in phases 2 and 3 (p = 0.042). Of phase 1 patients, 2.9% had neoadjuvant chemoradiotherapy compared to 32.7% of patients in phases 2 and 3 (p < 0.001). Splenic flexure was mobilized in 8.6% of phase 1 patients compared to 56.8% of patients in phases 2 and 3 (p < 0.001). Median blood loss was <50 ml in all three phases. The patients in phases 2 and 3 had a longer hospital stay compared to those in phase 1 (9 vs. 8 days, p = 0.002). There were no conversions.

CONCLUSION

At least three phases in the learning curve for robot-assisted rectal surgery are defined in our study.

One hundred sixty-four consecutive beating heart totally endoscopic coronary artery bypass cases without intraoperative conversion

BACKGROUND

Totally endoscopic coronary artery bypass graft (TECABG) surgery has been found to be feasible, but numerous reports associate the procedure with high conversion rates. This report aims to discuss 164 consecutive beating heart TECABG cases without intraoperative conversion to open CABG as well as potential steps to minimize conversion.

METHODS

Since July 2008, 164 consecutive beating heart TECABG cases were completed without intraoperative conversion. There were 128 male and 36 female patients, with mean age of 62.73 ± 10.51 years (range, 29 to 85). The da Vinci S robotic system with EndoWrist stabilizer was used for the entire procedure through four to five port incisions. Anastomoses were constructed using U-Clips (n = 182) or Flex-A device (n = 54). Two hundred fourteen grafts (88%) were studied in 146 patients (89%) before discharge. Twenty-nine patients (18%) who underwent hybrid coronary revascularization had conventional angiography of bypass grafts whereas 117 patients (71%) had computed tomography angiography to assess gross graft patency.

RESULTS

All patients underwent planned surgical and hybrid revascularization. Single, double, triple, and quadruple vessel beating heart TECABGs were performed in 93, 64, 6, 1 patients, respectively (average 1.48 ± 0.6 grafts per patient). There was no intraoperative conversion to CPB or open CABG technique. There was 1 in-hospital mortality. Two hundred thirteen grafts (99.5%) were found to be patent. Intracoronary shunt was used for 29 anastomoses.

CONCLUSIONS

Beating heart TECABG conversion rates decline with experience and thorough preoperative planning as well as with implementation of specific steps to minimize conversion.

Outlier analysis in orthopaedics: use of CUSUM: the Scottish Arthroplasty Project: shouldering the burden of improvement

National joint registries have become well established across the world. Most registries track implant survival so that poorly performing implants can be removed from the market. The Scottish Arthroplasty Project was established in 1999 with the aim of encouraging continual improvement in the quality of care provided to joint replacement patients in Scotland. This aim has been achieved by using statistics to engage surgeons in the process of audit. We monitor easily identifiable end points of public concern and inform surgeons if they breach our statistical limits and become "outliers." Outlier status is often associated with poor implants, and our methods are therefore applicable for indirect implant surveillance. The present report describes the evolution of our statistical methodology, the processes that we use to promote positive changes in practice, and the improvements in patient outcomes that we have achieved. Failure need not be fatal, but failure to change almost always is. We describe the journey of both the Scottish Arthroplasty Project and the orthopaedic surgeons of Scotland to this realization.

Objective measures for longitudinal assessment of robotic surgery training

OBJECTIVES

Current robotic training approaches lack the criteria for automatically assessing and tracking (over time) technical skills separately from clinical proficiency. We describe the development and validation of a novel automated and objective framework for the assessment of training.

METHODS

We are able to record all system variables (stereo instrument video, hand and instrument motion, buttons and pedal events) from the da Vinci surgical systems using a portable archival system integrated with the robotic surgical system. Data can be collected unsupervised, and the archival system does not change system operations in any way. Our open-ended multicenter protocol is collecting surgical skill benchmarking data from 24 trainees to surgical proficiency, subject only to their continued availability. Two independent experts performed structured (objective structured assessment of technical skills) assessments on longitudinal data from 8 novice and 4 expert surgeons to generate baseline data for training and to validate our computerized statistical analysis methods in identifying the ranges of operational and clinical skill measures.

RESULTS

Objective differences in operational and technical skill between known experts and other subjects were quantified. The longitudinal learning curves and statistical analysis for trainee performance measures are reported. Graphic representations of the skills developed for feedback to the trainees are also included.

CONCLUSIONS

We describe an open-ended longitudinal study and automated motion recognition system capable of objectively differentiating between clinical and technical operational skills in robotic surgery. Our results have demonstrated a convergence of trainee skill parameters toward those derived from expert robotic surgeons during the course of our training protocol.

The golden age of minimally invasive cardiothoracic surgery: current and future perspectives

Over the past decade, minimally invasive cardiothoracic surgery (MICS) has grown in popularity. This growth has been driven, in part, by a desire to translate many of the observed benefits of minimal access surgery, such as decreased pain and reduced surgical trauma, to the cardiac surgical arena. Initial enthusiasm for MICS was tempered by concerns over reduced surgical exposure in highly complex operations and the potential for prolonged operative times and patient safety. With innovations in perfusion techniques, refinement of transthoracic echocardiography and the development of specialized surgical instruments and robotic technology, cardiac surgery was provided with the necessary tools to progress to less invasive approaches. However, much of the early literature on MICS focused on technical reports or small case series. The safety and feasibility of MICS have been demonstrated, yet questions remain regarding the relative efficacy of MICS over traditional sternotomy approaches. Recently, there has been a growth in the body of published literature on MICS long-term outcomes, with most reports suggesting that major cardiac operations that have traditionally been performed through a median sternotomy can be performed through a variety of minimally invasive approaches with equivalent safety and durability. In this article, we examine the technological advancements that have made MICS possible and provide an update on the major areas of cardiac surgery where MICS has demonstrated the most growth, with consideration of current and future directions.

Off-Pump Positioning of a Conventional Aortic Valve Prosthesis through the Left Ventricular Apex with the Universal Cardiac Introducer under Sole Ultrasound Guidance, in the Pig

Objective

To test an alternative to catheter and open-heart techniques, by documenting the feasibility of implanting an unmodified mechanical aortic valve (AoV) in the off pump, beating heart using the universal cardiac introducer (UCI) attached to the left ventricular (LV) apex.

Methods

In six pigs, the LV apex was exposed by a median sternotomy. The UCI was attached to the apex. A 12-mm punching tool (punch), introduced through the UCI, was used to create a cylindrical opening through the apex. Then, the AoV, secured to a holder, was introduced into the LV, using transesophageal echocardiographic, guided through the apical LV opening, navigated into the LV outflow tract, and positioned within the aortic annulus. Trans-esophageal echocardiographic guidance was useful for navigation and positioning by superimposing the aortic annulus and prosthetic ring while Doppler imaging verified preserved prosthetic function and absence of perivalvular leaks. The valve function and hemodynamics were observed before termination for macroscopic evaluation.

Results

The punch produced a clean opening without fragmentation or myocardial embolization. During advancement of the mechanical AoV, there were no arrhythmias, mitral valve dysfunctions, evidence of myocardial ischemia, or hemodynamic instability. The AoVs were well seated over the annulus, without obstructing the coronaries or contact with the conduction system. The ring of AoVs was well circumscribed by the aortic annulus.

Conclusions

This study documented the feasibility of positioning a mechanical AoV on the closed, beating heart. These results should encourage the development of adjunct technologies to deliver current tissue or mechanical AoV with minimal side effects.

Cumulative sum failure analysis for eight surgeons performing minimally invasive direct coronary artery bypass

OBJECTIVE

Analysis of average and individual surgical performance for minimally invasive direct coronary artery bypass was used to enhance quality control for that operation.

METHODS

A total of 1441 standard minimally invasive direct coronary artery bypass procedures performed from August 1996 to January 2006 were analyzed for mortality and 10 other major perioperative complications. Learning curves and assessment of perioperative outcome were calculated using descriptive statistics and cumulative sum observed minus expected failure analysis for 8 involved surgeons with a personal experience ranging from 27 to 443 procedures.

RESULTS

The incidence of in-hospital mortality was 0.9% and compared favorably with the predicted mortality calculated by the logistic EuroSCORE (3.6%, P < .01). Cumulative sum analysis revealed that 2 surgeons crossed the 95% reassurance boundary after 50 operations and that 2 surgeons crossed the 95% reassurance boundary after 100 operations. There were significant differences between surgeons with regard to the learning curves and perioperative complications (3.6%-29.6%, P < .01). Two surgeons crossed the 95% alarm-line indicating unacceptably high failure rates.

CONCLUSIONS

Minimally invasive direct coronary artery bypass has become a procedure with low mortality and low complication rates, but results are case-load and surgeon dependent. Cumulative sum analysis is a valuable method allowing for a breakdown of complication rates over time displaying individual surgeons' strengths.

Quality control of surgical and interventional procedures: a review of the CUSUM

BACKGROUND

The report of the CUSUM across surgical and interventional procedures has spawned a fair confusion in the literature.

AIM

To assess the use of the CUSUM and to clarify its utilisation in the perspective of future studies. Nature of the study: Retrospective review.

METHODS

A systematic literature search of Medline was carried out. From each article, data regarding the design of the study, the specialty, the performance criterion, the unit under control, the methodology and the model of the CUSUM used, the use of a graph, the use of a test and the type of test applied were retrieved.

RESULTS

31 studies were found relevant. The design was mainly retrospective for the analysis of the learning curve. The main performance criteria under control were morbidity, mortality and success of the procedure. A graph was plotted in all studies as a CUSUM plot or as cumulative sums of non-negative values. A test was used in 17 studies. Mislabelling of the plot and the test, and misuse of control limits were the most commonly reported mistakes.

CONCLUSION

The CUSUM tool is not yet properly reported in the surgical literature. Therefore, reporting of the CUSUM should be clarified and standardised before its use widens.

Direct comparison of risk-adjusted and non–risk-adjusted CUSUM analyses of coronary artery bypass surgery outcomes

OBJECTIVE

We previously applied non-risk-adjusted cumulative sum methods to analyze coronary bypass outcomes. The objective of this study was to assess the incremental advantage of risk-adjusted cumulative sum methods in this setting.

METHODS

Prospective data were collected in 793 consecutive patients who underwent coronary bypass grafting performed by a single surgeon during a period of 5 years. The composite occurrence of an "adverse outcome" included mortality or any of 10 major complications. An institutional logistic regression model for adverse outcome was developed by using 2608 contemporaneous patients undergoing coronary bypass. The predicted risk of adverse outcome in each of the surgeon's 793 patients was then calculated. A risk-adjusted cumulative sum curve was then generated after specifying control limits and odds ratio. This risk-adjusted curve was compared with the non-risk-adjusted cumulative sum curve, and the clinical significance of this difference was assessed.

RESULTS

The surgeon's adverse outcome rate was 96 of 793 (12.1%) versus 270 of 1815 (14.9%) for all the other institution's surgeons combined (P = .06). The non-risk-adjusted curve reached below the lower control limit, signifying excellent outcomes between cases 164 and 313, 323 and 407, and 667 and 793, but transgressed the upper limit between cases 461 and 478. The risk-adjusted cumulative sum curve never transgressed the upper control limit, signifying that cases preceding and including 461 to 478 were at an increased predicted risk. Furthermore, if the risk-adjusted cumulative sum curve was reset to zero whenever a control limit was reached, it still signaled a decrease in adverse outcome at 166, 653, and 782 cases.

CONCLUSIONS

Risk-adjusted cumulative sum techniques provide incremental advantages over non-risk-adjusted methods by not signaling a decrement in performance when preoperative patient risk is high.

Image-guidance for surgical procedures

Contemporary imaging modalities can now provide the surgeon with high quality three- and four-dimensional images depicting not only normal anatomy and pathology, but also vascularity and function. A key component of image-guided surgery (IGS) is the ability to register multi-modal pre-operative images to each other and to the patient. The other important component of IGS is the ability to track instruments in real time during the procedure and to display them as part of a realistic model of the operative volume. Stereoscopic, virtual- and augmented-reality techniques have been implemented to enhance the visualization and guidance process. For the most part, IGS relies on the assumption that the pre-operatively acquired images used to guide the surgery accurately represent the morphology of the tissue during the procedure. This assumption may not necessarily be valid, and so intra-operative real-time imaging using interventional MRI, ultrasound, video and electrophysiological recordings are often employed to ameliorate this situation. Although IGS is now in extensive routine clinical use in neurosurgery and is gaining ground in other surgical disciplines, there remain many drawbacks that must be overcome before it can be employed in more general minimally-invasive procedures. This review overviews the roots of IGS in neurosurgery, provides examples of its use outside the brain, discusses the infrastructure required for successful implementation of IGS approaches and outlines the challenges that must be overcome for IGS to advance further.

Transplant center quality assessment using a continuously updatable, risk-adjusted technique (CUSUM)

Access to timely, risk-adjusted measures of transplant center outcomes is crucial for program quality improvement. The cumulative summation technique (CUSUM) has been proposed as a sensitive tool to detect persistent, clinically relevant changes in transplant center performance over time. Scientific Registry of Transplant Recipients data for adult kidney and liver transplants (1/97 to 12/01) were examined using logistic regression models to predict risk of graft failure (kidney) and death (liver) at 1 year. Risk-adjusted CUSUM charts were constructed for each center and compared with results from the semi-annual method of the Organ Procurement and Transplantation Network (OPTN). Transplant centers (N = 258) performed 59 650 kidney transplants, with a 9.2% 1-year graft failure rate. The CUSUM method identified centers with a period of significantly improving (N = 92) or declining (N = 52) performance. Transplant centers (N = 114) performed 18 277 liver transplants, with a 13.9% 1-year mortality rate. The CUSUM method demonstrated improving performance at 48 centers and declining performance at 24 centers. The CUSUM technique also identified the majority of centers flagged by the current OPTN method (20/22 kidney and 8/11 liver). CUSUM monitoring may be a useful technique for quality improvement, allowing center directors to identify clinically important, risk-adjusted changes in transplant center outcome.

Skills training in telerobotic surgery

Surgical robots have the potential to expand the repertoire of minimally invasive surgery resulting in more patients benefiting from lower operative morbidity and shorter hospital stays. However, in a similar manner to all new surgical interventions it necessary to explore the learning curves of practitioners as they adopt this new technology to enable optimisation of future training programs. Only when the standard of practice is firmly established, should the proliferation of robotic practitioners be encouraged thus ensuring patient safety is not compromised.

Learning curve of coronary surgery by a cardiac surgeon in Japan with the use of cumulative sum analysis

OBJECTIVE

Case-volume has been believed to be of paramount importance in becoming a good cardiac surgeon. However, for a training cardiac surgeon there is no evidence regarding the specific number of necessary cases to attain the medico-legally acceptable level. We attempted to observe the learning curve in performing coronary surgery with the use of the cumulative sum (CUSUM) method to provide some evidence.

METHODS

From April 2000 to March 2004, a cardiac surgeon, being board-certified but not being on the attending staff, performed 50 coronary artery bypass grafting (CABG) under supervision of three different chief attending surgeons at three different hospitals. His learning curve was analyzed with the use of CUSUM. Mortality and morbidity and the average time of crossclamp and operation at each hospital were examined. Also, the learning curve of 100 left internal mammary artery (LIMA) harvestings were analyzed via CUSUM in terms of harvesting time and injury rate.

RESULTS

The CUSUM curve tended to come closer to the alert line (0.80 confidence) until the 23rd case, but never reached the alert line thereafter until the 50th case. The CUSUM curve never transgressed the alarm line (0.95 confidence) throughout 50 cases. The CUSUM curve of LIMA harvesting approached the alert line in the 38th case and the 59th case, but thereafter never reached the alert line and remained below the reassurance line from the 73rd case.

CONCLUSION

Tentatively, it is inferred that approximately 23 cases of CABG may be sufficient to allow for independent practice and that 73 cases of LIMA harvesting are sufficient to allow independent practice.

Robotics in reproductive medicine

OBJECTIVE

To review the history, development, current applications, and future of robotic technology.

DESIGN

The MEDLINE database was reviewed for all publications on robotic technology in medicine, surgery, reproductive endocrinology, its role in surgical education, and telepresence surgery.

SETTING

University medical center.

CONCLUSION(S)

Robotic-assisted surgery is an emerging technology, which provides an alternative to traditional surgical techniques in reproductive medicine and may have a role in surgical education and telepresence surgery.

A cumulative analysis of an individual surgeon's early experience with elective open abdominal aortic aneurysm repair

BACKGROUND

Several studies have reviewed the role of hospital and surgeon case volumes in determining early mortality after elective open abdominal aortic aneurysm (AAA) repair. Few, however, have analyzed this relationship at the individual surgeon level. The purpose of this study was to display the usefulness of a unique statistical tool as a form of an ongoing practice audit.

METHODS

All patients who underwent an elective open AAA repair by an individual surgeon at a university-affiliated medical center over a 5-year period were analyzed. The cumulative sum failure method was used to analyze the results over time. Failure was defined as the presence of early mortality, myocardial infarction, or a complication resulting in another surgical procedure or prolonged hospitalization. A target failure rate of 10% was chosen, and 80% alert and 95% alarm boundary lines were established.

RESULTS

One hundred thirty-eight patients underwent elective AAA repair by this surgeon over a 5-year period (1998-2003). There were 5 early mortalities (3.6%), 15 myocardial infarctions (10.9%), and 3 major morbidities (2.2%). These results were plotted on a cumulative sum curve as an example of an ongoing practice audit.

CONCLUSIONS

The cumulative sum failure method provides a tool whereby a surgeon can prospectively audit his practice and recognize trends in performance before their recognition by standard statistical tools.

Results of a phase one study on robotically assisted myocardial revascularization on the beating heart

BACKGROUND

The objective of this study was to evaluate the feasibility of computer assisted myocardial revascularization on the beating heart.

METHODS

Ten patients underwent at least one robotically assisted internal mammary artery (IMA) anastomosis utilizing the da Vinci surgical system (Intuitive Surgical, Inc, Mountain View, CA) performed through an open incision as part of standard multivessel off pump revascularization. Following chest closure a selective IMA angiogram was performed to assess patency. Three month follow-up included a stress echocardiogram.

RESULTS

There were 12 anastomoses performed in 10 patients. The average age was 61 years with a mean ejection fraction of 56%. No patient required inotropic support. Eight of 10 patients were found to have fully patent IMA anastomoses by angiogram. One patient was noted to have an occluded left anterior descending coronary artery distal to the anastomosis and one had occlusion at the anastomosis. Both patients had immediate manual revision of the anastomosis. One patient who required anastomotic revision experienced postoperative myocardial infarction and sternal wound infection requiring pectoralis flaps.

CONCLUSIONS

Because robotic instrumentation is meant for closed chest procedures, there were major issues with positioning of the robotic arms in this study since the chest was open. Although two patients required anastomotic revision, there were no complications or technical failures related to the robotic system. Thus, based upon this study robotically assisted beating heart revascularization appears to be feasible, safe, and effective. Further evaluation will be necessary to determine the role of robotically assisted totally endoscopic coronary artery bypass on the beating heart in the United States.