Introduction: There is increasing literature supporting the importance in triaging patients to teaching hospitals for complex surgical procedures. This study analyzes the effect of teaching hospital status on outcome of endovascular coiling and microsurgical clipping of ruptured and unruptured intracranial aneurysms using the Nationwide Inpatient Sample (NIS) database.
Methods: We analyzed patients with cerebral aneurysms using NIS 2001 to 2010. Patients with ruptured aneurysms were identified by ICD-9 codes for diagnoses of subarachnoid hemorrhage or intracerebral hemorrhage and at least one procedural code for aneurysm repair. Patients with unruptured cerebral aneurysms were identified by diagnosis code 437.3 and at least one procedural code. Multivariate linear models were used to analyze the association of in-hospital death, non-routine discharge, and length of stay with teaching hospital status, adjusting for patient age, sex, race, comorbidities, household income, time to aneurysm repair procedure, aneurysm procedure volume, hospital region and location.
Results: There were 34,843 hospitalizations for treatments of unruptured (14,763 in teaching and 1794 in non-teaching hospitals) and ruptured (15,628 in teaching and 2658 in non-teaching hospitals) aneurysms. In patients with ruptured aneurysms, the odds ratio of in-hospital death and non-routine discharges were 0.69 (95% CI 0.54-0.88) and 0.77 (95% CI 0.60-0.99) in teaching hospitals, respectively, independent of hospital aneurysm procedure volume. Moreover, the disparity in mortality rate in teaching versus non-teaching hospitals seemed even more pronounced for those treated with clipping (OR 0.62, 95% CI 0.46-0.84). These differences in outcome parameters were not observed in the unruptured population, in which mortality, non-routine discharges and length of stay were not different between those treated at teaching and non teaching hospitals.
Conclusions: Our results suggest that the teaching status of a hospital is an independent factor for favorable outcome in the treatment of ruptured aneurysms. The difference in in-hospital death is accentuated in patients who underwent microsurgical clipping.
Patient Care: While controversies continue to exist on the effect of hospital teaching status on patient outcome, our findings suggest that academic institutions are associated with reduced mortality and non-routine discharges in patients treated for ruptured cerebral aneurysm. Due to the complexity of managing complications associated with treating ruptured aneurysms, it is critical to direct patients with ruptured aneurysms to hospitals with best outcomes.
Learning Objectives: By the conclusion of this session, participants should be able to:
1) Describe the effect of teaching hospital status on the outcome of patients with ruptured cerebral aneurysm
2) Discuss the use and limitations of the Nationwide Inpatient Sample database
References: Dimick JB, Cowan JA, Jr., Colletti LM, Upchurch GR, Jr.: Hospital teaching status and outcomes of complex surgical procedures in the United States. Archives of surgery 139:137-141, 2004.
McDonald RJ, Cloft HJ, Kallmes DF: Impact of admission month and hospital teaching status on outcomes in subarachnoid hemorrhage: evidence against the July effect. Journal of neurosurgery 116:157-163, 2012.
Meguid RA, Brooke BS, Perler BA, Freischlag JA: Impact of hospital teaching status on survival from ruptured abdominal aortic aneurysm repair. Journal of vascular surgery : official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter 50:243-250, 2009.
Phillips DP, Barker GE: A July spike in fatal medication errors: a possible effect of new medical residents. Journal of general internal medicine 25:774-779, 2010.