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

Defining the cardiac surgical learning curve: a longitudinal cumulative analysis of a surgeon's experience and performance monitoring in the first decade of practice

BACKGROUND

Individual surgeons' learning curves are a crucial factor impacting patient outcomes. While many studies investigate procedure-specific learning curves, very few carried out a longitudinal analysis of individual cardiac surgeons over the course of their career. Given the evolving landscape of cardiac surgery with the introduction of transcatheter and robotic procedures, a contemporary evaluation of the cardiac surgical learning curve is justified and a method of personal performance monitoring is proposed in this study.

METHODS

A retrospective study of 1578 consecutive patients of a cardiac surgeon over ten years was undertaken. Risk adjustment was based on Euroscore. Cumulative risk adjusted morbidity (CRAM) charts of operative mortality, return to theatre and length of stay were constructed. Secondary endpoints included postoperative stroke and deep sternal wound infection. Change-point detection was applied to investigate temporal trends and identify when a significant change in outcome occurred. Multivariate analysis was performed to assess the influence of patient and system factors on operative mortality.

RESULTS

Patient average risk profile was highest in the later years of practice. Cardiopulmonary bypass time remained stable from 86.5 to 92 min across the decade. The frequency of redo operations increased from 4.07% in the first two years of practice to 9.29% in the last two years. The proportion of aortic surgery increased from 6.98 to 10.58% of total cases. There was a significantly reduced operative mortality signalled at case 1220 with the change point identified around case 970.

CONCLUSION

This prompts training colleges to consider application of sequential performance monitoring in surgical training programs, to confirm the progress of trainees and identify early evolving patterns that suggest support is required or milestones are being achieved.

Learning Curve of Arch-First Technique Analyzed by Cumulative Sum

This study was undertaken to verify efficacy of the arch-first technique in the light of its learning curve. From April 2002 to September 2005, 10 consecutive elective cases of total arch replacement were retrospectively examined. The learning curve of the arch-first technique was constructed using cumulative sum analysis. There were no operative deaths. The mean deep hypothermic circulatory arrest time was 28.4 ± 13.7 min, the lower body ischemic time was 91.3 ± 35.1 min, aortic cross clamp time was 133.2 ± 18.1 min, cardiopulmonary bypass time was 198.8 ± 21.5 min, and operation time was 383 ± 24 min. The durations of deep hypothermic circulatory arrest, bypass, and operation were under the 90% lower alarm line in all 10 cases. The lower body ischemic time and cardiac arrest time were between the 80% upper and lower alert lines. Cumulative sum analysis of total arch replacement using the arch-first technique showed satisfactory rates of improvement in reconstruction of the 3 arch vessels, cardiopulmonary bypass time, and overall mortality.

Surgical learning curves and operative efficiency: a cross-specialty observational study

OBJECTIVES

To evaluate the learning curves of three high-volume procedures, from distinct surgical specialties.

SETTING

Tertiary care academic hospital.

PARTICIPANTS

A prospectively collected database comprising all medical records of patients undergoing isolated coronary artery bypass grafting (CABG), total knee replacement (TKR) and bilateral reduction mammoplasty (BRM) at the Brigham and Women's Hospital, USA, 1996-2010. Multivariate generalised estimating equation (GEE) regression models were used to adjust for patient risk and clustering of procedures by surgeon.

PRIMARY OUTCOME MEASURE

Operative efficiency.

RESULTS

A total of 1052 BRMs, 3254 CABGs and 3325 TKRs performed by 30 surgeons were analysed. Median number of procedures per surgeon was 61 (range 11-502), 290 (52-973) and 99 (10-1871) for BRM, CABG and TKR, respectively. Mean operative times were 134.4 (SD 34.5), 180.9 (62.3) and 101.9 (30.3) minutes, respectively. For each procedure, attending surgeon experience was associated with significant reductions in operative time (p<0.05). After 15 years of experience, BRM operative time decreased by 69.8 min (38.3%), CABG operative time decreased by 17.5 min (7.8%) and TKR operative time decreased by 94.4 min (48.4%).

CONCLUSIONS

Common trends in surgical learning exist. Dependent on the procedure, experience can serve as a powerful driver of improvement or have clinically insignificant impacts on operative time.

Association of Robotic Totally Endoscopic Coronary Artery Bypass Graft Surgery Associated With a Preliminary Cardiac Enhanced Recovery After Surgery Program: A Retrospective Analysis

OBJECTIVES

The robotic totally endoscopic coronary artery bypass graft (TECAB) surgery reduces patients' recovery time. The present trial investigated the feasibility and safety of an initial enhanced recovery after surgery (ERAS) path for patients undergoing robotic beating-heart TECAB and compared it with both conventional surgery and traditional perioperative care. It was hypothesized that the preliminary ERAS pathway associated with a beating-heart TECAB procedure could have a synergistic effect on postoperative patient care.

DESIGN

Observational retrospective study.

SETTING

University hospital.

PARTICIPANTS

Patients scheduled for coronary artery bypass graft and undergoing robotic beating-heart TECAB (n = 38) were compared with those undergoing standard surgery and perioperative care (n = 33). The outcomes were the possibility of tracheal extubation at the end of the surgery and the incidence of postoperative complications.

MEASUREMENTS AND MAIN RESULTS

The main comorbidities were similar between the 2 groups. Extubation on the operating table in the TECAB group was possible in all cases without requiring prompt endotracheal tube reinsertion. The proportion of patients transfused was significantly lower in the TECAB group (p = 0.009). In addition, the duration of intensive care unit and hospital stay were reduced significantly by 24 hours and by 4 days, respectively, in the TECAB group compared with the standard group (p< 0.05).

CONCLUSIONS

The present results suggested that a program coupling a beating-heart TECAB with a preliminary ERAS path for patients requiring a single coronary revascularization is feasible and safe. This approach could reduce postoperative mechanical ventilation time, transfusion rate, and both intensive care unit and hospital stay.

Learning curves for cardiothoracic and vascular surgical procedures--a systematic review

OBJECTIVES

The aim of this systematic review is to evaluate the learning curve (LC) literature and identify the LC of cardiothoracic and vascular surgical procedures.

SUMMARY AND BACKGROUND

The LC describes an observation that a learner's performance improves over time during acquisition of new motor skills. Measuring the LC of surgical procedures has important implications for surgical innovation, education, and patient safety. Numerous studies have investigated LCs of isolated operations in cardiothoracic and vascular surgeries, but a lack of uniformity in the methods and variables used to measure LCs has led to a lack of systematic reviews.

METHODS

The MEDLINE®, EMBASE™, and PsycINFO® databases were systematically searched until July 2013. Articles describing LCs for cardiothoracic and vascular procedures were included. The type of procedure, statistical analysis, number of participants, procedure setting, level of participants, outcomes, and LCs were reviewed.

RESULTS

A total of 48 studies investigated LCs in cardiothoracic and vascular surgeries. Based on operating time, the LC for coronary artery bypass surgery ranged between 15 and 100 cases; for endoscopic vessel harvesting and other cardiac vessel surgery between 7 and 35 cases; for valvular surgery, which included repair and replacement, between 20 and 135 cases; for video-assisted thoracoscopic surgery, between 15 and 35 cases; for vascular neurosurgical procedures between 100 and 500 cases, based on complications; for endovascular vessel repairs between 5 and 40 cases; and for ablation procedures between 25 and 60 cases. However there was a distinct lack of standardization in the variables/outcome measures used, case selection, prior experience, and supervision of participating surgeons and a range of statistical analyses to compute LCs was noted.

CONCLUSION

LCs in cardiothoracic and vascular procedures are hugely variable depending on the procedure type, outcome measures, level of prior experience, and methods/statistics used. Uniformity in methods, variables, and statistical analysis is needed to derive meaningful comparisons of LCs. Acknowledgment and application of learning processes other than those reliant on volume-outcomes relationship will benefit LC research and training of surgeons.

Five hundred cases of robotic totally endoscopic coronary artery bypass grafting: predictors of success and safety

BACKGROUND

Robotic technology has enabled totally endoscopic coronary artery bypass (TECAB) grafting. Little information is available on factors associated with successful and safe performance of TECAB. We report a 10-year multicenter experience with 500 cases, elucidating on predictors of success and safety in TECAB procedures.

METHODS

Between 2001 and 2011, 500 patients (364 [73%] men; 136 [27%] women; median age [minimum-maximum] 60 years [31-90 years], median EuroSCORE 2 [0-13]), underwent TECAB. Single, double, triple, and quadruple TECAB was performed in 334, 150, 15, and 1 patient, respectively. Univariate analysis and binary regression models were used to identify predictors of success and safety. Success was defined as freedom from any adverse event and conversion procedure, safety was defined as freedom from major adverse cardiac and cerebral events, major vascular injury, and long-term ventilation.

RESULTS

Success and safety rates were 80% (400 cases) and 95% (474 cases), respectively. Intraoperative conversions to larger thoracic incisions were required in 49 (10%) patients. The median operative time was 305 minutes (112-1,050 minutes), and the mean lengths of stay in the intensive unit (ICU) and in hospital were 23 hours (11-1,048 hours) and 6 days (2-4 days), respectively. Independent predictors of success were single-vessel TECAB (p = 0.004), arrested-heart (AH)-TECAB (p = 0.027), non-learning curve case (p = 0.049), and transthoracic assistance (p = 0.035). The only independent predictor of safety was EuroSCORE (p = 0.002).

CONCLUSIONS

Single-vessel and multivessel TECAB procedures can be safely performed with good reproducible results. Predictors of success include procedure simplicity and non-learning curve cases, whereas predictors of safety are mainly associated with patient selection.

A Learning Curve in Bentall and De Bono Procedure with the Use of the Risk-Adjusted Cumulative Sum Analysis Based on the Japan SCORE

<p><b>Objective:</b> The risk-adjusted cumulative sum analysis of an individual surgical learning curve for the Bentall and De Bono procedure on aortic root pathologies was used to monitor and enhance quality control.</p><p><b>Methods:</b> From April 2004 to March 2009, 20 consecutive patients were operated upon by a single surgeon for aortic root pathologies by means of the Bentall and De Bono procedure. Operative variables, mortality, and major morbidities were analyzed. The learning curve was calculated using descriptive statistics and cumulative sum failure observed minus expected failure rate derived from the Japan SCORE calculator.</p><p><b>Results:</b> In this series, the Japan SCORE calculator expected 3.91% � 5.14% of 30-day operative mortality rate and 16.74 � 13.47% of 30-day operative mortality and morbidity. In reality, there was no operative and in-hospital death. Major postoperative morbidity rate was 15.0% (3 patients). The risk-adjusted cumulative sum analysis revealed that the learning curve of mortality was downward below the lower 95% confidence interval throughout all the patients and that of morbidity was upward till the seventh case and remained downward thereafter. The polynomial approximation coefficient analysis revealed a significant negative correlation between aortic cross-clamp time, cardiopulmonary time, and operation time and case load.</p><p><b>Conclusions:</b> The Bentall and De Bono procedure for aortic root pathologies was performed at the professionally permissive level from the beginning, even in a low-volume environment. It showed one good example of a learning curve. The risk-adjusted cumulative sum analysis based on the Japan SCORE was a very useful tool for monitoring the performance.</p>

Safe launching of a newly appointed cardiac surgery unit at a low-volume hospital with the use of cumulative sum analysis

BACKGROUND

Few studies have used the cumulative sum method to examine the initial performance of a newly appointed cardiac surgery team at a low-volume hospital.

METHODS AND RESULTS

In the 4 years from April 2002 to December 2006, 274 cases of open-heart surgery were performed and the overall mortality and morbidity rates were 4.01% and 5.84%, respectively. The respective rates for coronary, valvular and aortic surgery were 2.05% and 2.74%, 3.61% and 7.23%, and 11.1% and 13.3%. The overall cumulative sum curve was below the 80% upper alarm line since the 58(th) case and below the 80% lower alarm line since the 139th case. The respective values for the cumulative sum curves of valvular and coronary surgery were the 1st and 41st cases, the 22nd and the 76th cases, but for aortic surgery the cumulative sum curve remained below the 80% upper alarm line since the 1st case but did not reach below the 80% lower alarm line

CONCLUSIONS

An open-heart surgery unit at a low-volume hospital could compete with a high-volume hospital if it has a safe launching and low mortality and morbidity rates. The predictor of a safe launching is not the annual volume, but the cumulative experience of the surgical team.

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.