The impact of short breaks from cardiac surgery on mortality and stay length in California

The well-known "learning by doing" may operate in reverse as "forgetting after not doing." If so, patient outcomes such as length of stay (LOS) or mortality may be affected after a surgeon returns from a month-long vacation or break from surgery. In a small, exploratory and hypothesis-screening study, we examined all 56,956 patients undergoing isolated coronary artery bypass grafts (CABGs) in California in 2003-2005. We compared the outcomes of patients operated on by surgeons who had or had not performed any isolated CABG procedures in the calendar month prior to the month of their own surgery. Sensitivity analyses considered surgeons who had performed less than their own typical monthly workload, rather than none at all. We used multivariate regressions and controlled for patient risk factors and long-run surgeon average monthly volume. Patients operated on by surgeons who had not performed isolated CABG in the prior calendar month stayed in hospital 0.5 day longer (p = .037). This LOS difference was not robust to corrections for skewed data and in models correcting for clustering of patients within the practices of surgeons. There were no significant differences in hospital or 30-day mortality. These preliminary findings from a small, exploratory study suggest that short breaks by cardiac surgeons do not affect key patient outcomes. However, the patient safety ramifications of the underlying question deserve more research and more granular data to more convincingly rule out "forgetting" effects among physicians taking short breaks from practice.