Examining the myth of the "July Phenomenon" in surgical patients

Background: The objective of this study is to evaluate morbidity and mortality rates in surgical patients at the beginning of the academic year.

Methods: The National Surgical Quality Improvement Program database was utilized to gather data on the 10 most common inpatient operative procedures from 2005-2007. Study end points included mortality, serious adverse events (SAE), and all morbidities. Statistical analysis of outcomes was conducted examining the total population, and then stratified by operation to assess for significant differences in end points (P < .05).

Results: A total of 89,473 patients were identified. During the first academic quarter, the mortality rate was no different in the study group than the control group (2.0% vs 2.2%, P = .793). Overall SAE and morbidity rates were similar between populations (11.5% vs 11.4%, P = .697 and 18.3% vs 17.8%, P = .076, respectively). When stratified by operation, "artery bypass graft" (3.7% vs 2.9%, P = .039) and "repair bowel opening" (1.1% vs 0.6%, P = .033) subsets had increases in mortality rate. Multivariate analysis confirmed the deleterious effect of first quarter admission in only the "artery bypass graft" subset (OR = 1.35, CI 1 = .023-1.774).

Conclusion: By in large, these data refute the "July Phenomenon." Multivariate analysis revealed patient disease to have a greater impact than timing of operation in the "repair bowel opening" subset. The "artery bypass graft" population was affected by timing of operation and the very small effect on mortality (<1%) may reflect new surgery residents being unfamiliar with the management of complex cardiovascular disease.