Prospective assessment of intraoperative precursor events during cardiac surgery.

Objective: Increasing attention has been afforded to the ubiquity of medical error and associated adverse events in medicine. There remains little data on the frequency and nature of precursor events in cardiac surgery, and we sought to characterize this.
Methods: Detailed, anonymous information regarding intraoperative precursor events (which may result in adverse events) was collected prospectively from six key members of the operating team during 464 major adult cardiac surgical cases at three hospitals and were analyzed with univariable statistical methods.
Results: During 464 cardiac surgical procedures, 1627 reports of problematic precursor events were collected for an average of 3.5 and maximum of 26 per procedure. 73.3% of cases had at least one recorded event. One-third (33.3%) of events occurred prior to the first incision, and 31.2% of events occurred while on bypass. While 68.0% of events were regarded as minor in severity (e.g., delays and missing equipment), a substantial proportion (32.0%) was considered major and included anastomotic problems, pump failure, and drug errors. Most problems (90.4%) were reported as being compensated for, although many (30.9%) were never discussed among the team. Major events were more likely to be discussed (p<0.0001) and less likely to have been previously encountered (p=0.0005). Perceptions of the severity and compensation of events varied across the team, as did temporal patterns of reporting (p<0.0001).
Conclusions: A wide range of problematic precursor events occurs during the majority of cardiac surgery procedures. Attention to causes and ways of preventing these precursor events could have an impact on the rate of significant errors and improve the safety of cardiac surgery.