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Cumulative sum failure analysis for eight surgeons performing minimally invasive direct coronary artery bypass
David M Holzhey1, Stephan Jacobs, Thomas Walther
1Department of Cardiac Surgery, Heart Center Leipzig, Leipzig, Germany. dholzhey@web.de
Insights
Minimally invasive direct coronary artery bypass shows low mortality, but outcomes depend on surgeon experience. Cumulative sum analysis effectively tracks individual surgical performance and identifies potential issues.
Area of Science:
- Cardiovascular Surgery
- Surgical Quality Improvement
- Medical Device Technology
Background:
- Minimally invasive direct coronary artery bypass (MIDCAB) is a complex procedure.
- Effective quality control is essential for optimizing MIDCAB outcomes.
- Surgeon experience significantly impacts patient results.
Purpose of the Study:
- To analyze surgical performance in MIDCAB procedures.
- To enhance quality control through individual surgeon performance assessment.
- To evaluate the effectiveness of cumulative sum analysis in surgical quality monitoring.
Main Methods:
- Analysis of 1441 MIDCAB procedures from 1996-2006.
- Assessment of mortality and 10 major perioperative complications.
- Application of cumulative sum (CUSUM) analysis for 8 surgeons with varying experience levels.
Main Results:
- In-hospital mortality was 0.9%, lower than predicted (3.6%).
- CUSUM analysis identified surgeons reaching performance boundaries.
- Significant variations in learning curves and complication rates (3.6%-29.6%) were observed among surgeons.
Conclusions:
- MIDCAB offers low mortality and complication rates.
- Procedure outcomes are dependent on case-load and surgeon expertise.
- CUSUM analysis is a valuable tool for monitoring individual surgeon performance and identifying strengths over time.
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.
