According to a study published ahead of print in the Journal of Neurosurgery: Spine, by Jennifer McDonald (Department of Radiology, Mayo Clinic, Rochester, USA) and others, the influx of new residents and fellows in teaching hospitals at the start of the academic year has a minimal effect on periprocedural outcomes following spinal surgery
McDonald et al reported that the intake of new residents and fellows during July (the start of the academic year) at teaching hospitals is sometimes associated with worse patient outcomes—known as the “July effect”. However, they wrote that the evidence for a July effect is varied, with some studies showing that outcomes are worse during July at teaching hospitals while others have shown no difference in outcomes compared with other months. They added: “Additional studies are therefore needed to determine whether patients are at an increased, significant risk of poor outcome in teaching hospitals during these transition months.” Furthermore, McDonald et al noted, a recent study showed higher rates of in-hospital mortality and intraoperative complications at teaching hospitals in July for patients with spinal metastatic disease, but it is not known whether this is the case for all patients undergoing spinal surgery.
The investigators used the US National Inpatient Sample (NIS) hospital discharge database to examine the rate of complications following spinal surgery and to “determine whether admission month and hospital teaching status affected these rates.” Of 57,663,486 hospital admissions between 2001 and 2008, 968,086 were related to spinal surgery and 55% (528,057) of these spinal procedures were at teaching hospitals.
McDonald et al commented that, after adjustment, patients admitted to a teaching hospital in July had similar rates of in-hospital mortality, reaction to implanted device/instrumentation, and postoperative wound dehiscence as patients admitted to teaching hospitals in other months. However, these patients did have a significantly higher likelihood of discharge to long-term care (p=0.0467) and postoperative infection (p=0.0341) than patients admitted to a teaching hospital in other months. Furthermore, in an analysis of differences in outcome between June and July, the authors found a slightly higher likelihood of postoperative wound dehiscence among those admitted in July (p=0.0301). They did not find any differences between patients admitted to a non-teaching hospital in July and patients admitted to a non-teaching hospital in other months.
In a subset of “higher-risk” patients (173, 268), patients admitted to a teaching hospital in July had a similar likelihood of all outcomes as patients admitted in other months but patients admitted to a non-teaching hospital had a significantly higher likelihood of in-hospital mortality (p=0.0392) and postoperative infection (0.0011) than patients admitted in other months (at a non-teaching hospital).
McDonald et al wrote the finding that a “minimal” July effect was observed in the overall cohort but not in a higher risk subset was surprising because higher risk patients are more likely to be susceptible to errors made by new fellows or residents than other patients. The authors stated a possible reason why a “July effect” in the higher risk subset was not observed is that new fellows/residents may be less involved in the care of higher risk patients. However, they added: “evidence for a July effect was also not observed in the subset of patients who were electively admitted, representing less urgent cases that may have been more likely to be monitored residents and fellows.”
McDonald told Spinal News International: “Our study provides additional evidence that patients who undergo spinal surgery at teaching hospitals in July are not at substantially increased risk of poor outcomes as compared to patients who undergo surgery during other months. Our findings therefore argue against the presence of a July effect in this patient population.”