‘July Effect’ Does Not Impact Cardiac Surgery

The “July effect,” in which the notion that an increased risk from a cardiac surgery done by new trainees leads to a spike in adverse outcomes, did not apply to cardiac surgery.

A new analysis in the Annals of Thoracic Surgery looked at data on various cardiac surgery procedures from the national inpatient sample, isolating all coronary artery bypass graft (CABG; n=301,105), surgical aortic valve replacement (AVR; n=111,260), mitral valve repair or replacement (MV; n=54,985), and isolated thoracic aortic aneurysm (TAA; n=2,655) replacement procedures between 2012 and 2014. The authors then compared overall trends in in-hospital mortality and hospital complications by academic year quartile and procedure by month. They also looked at outcomes between teaching and nonteaching hospitals.

According to the results, in-hospital mortality for each cardiac surgery procedure “did not vary by procedure month or academic year quartile, even after risk adjustment.” The authors also reported that teaching status had no effect on risk-adjusted mortality for CABG or isolated TAA replacement (P<0.05 for both). Teaching hospitals had significantly lower adjusted mortality than nonteaching hospitals for AVR and MV surgery (P<0.05 for both).

“Cardiac surgery patients are managed in a multidisciplinary fashion; therefore, the well-being of patients is not solely dependent on one individual, but rather on the entire caregiving team and so may be more resistant to changes in hospital staff,” said lead author Rohan M. Shah, MD, MPH, of Brigham and Women’s Hospital in Boston, in a press release. “What this means for patients is that they should not be fearful or concerned about having surgery in July when new residents are starting.”

The results should go a long way towards debunking this commonly held notion that cardiac surgery is more risky during certain months, according to another study author.

“While the perception of the ‘July effect’ persists culturally among health care providers, we hope that this study reinforces the fact that hospital systems have in place processes that help provide the highest level of care and ensure patient safety,” said coauthor Sameer A. Hirji, MD, also of Brigham and Women’s Hospital. “Our findings are encouraging.”