323 - Rates of Mortality in Lumbar Spine Procedures: A Study of 803,945 Pati...

#323 Rates of Mortality in Lumbar Spine Procedures: A Study of 803,945 Patients on the Nationwide Inpatient Sample

Value and Outcomes in Spine Surgery

Poster Presented by: G. Poorman

Author(s):

G. Poorman (1)
J. Moon (1)
C. Jalai (1)
S. Horn (1)
B. Beaubrun (1)
O. Bono (1)
V. Lafage (2)
P. Passias (1)

(1) NYU Hospital for Joint Diseases, Orthopaedic Surgery, New York, NY, United States
(2) Hospital for Special Surgery, New York, NY, United States

Abstract

Introduction: The most important risk, found in all surgical procedures, is of death. However, defining rates and causes of mortality can be difficult due to its rarity. In addition, causes for mortality are well understood, but risk factors for event occurrence may be difficult to estimate given study limits. This study aims to use a large patient cohort available on a national database in order to study the rare, but important, prevalence of death associated with lumbar spinal surgery.

Methods: This study was a retrospective review of the Nationwide Inpatient Sample (NIS) years 2003-12. 803,945 patients were identified by ICD-9-CM codes undergoing spinal fusion or decompression for disc degeneration, stenosis, spondylosis, myelopathy, postlaminectomy syndrome, scoliosis, or low back pain in the lumbar region. Trauma, fracture, and patients with cancer were excluded from analysis. Incidence of mortality was assessed by chi-squared tests across different patient demographics and comorbidities, procedures performed, and concurrent in-hospital complications. Binary logistic regression identified significant increases or decreases in risk of death while controlling for comorbidities, BMI, race, sex, and Mirza invasiveness. Significance was defined as p< 0.05 difference relative to overall cohort.

Results: Analysis captured 304,970 simple fusions (single approach and < 3 levels), 104,784 complex fusions (combined approach or ≥3 levels), and 364,494 decompression-only surgeries. Mortality in the entire 803,949 patient cohort was 0.13%. Simple fusions sustained 0.105% mortality, complex fusions 0.321%, and decompression-only 0.081%. Demographically, increased mortality was observed in male patients (p< 0.001), black-race patients (p=0.021), and patients in 65-74 and 75+ age cohort (p< 0.001). The greatest increased mortality was observed in patients with any liver disease, and congestive heart failure patients. Complications most associated with death were shock, pulmonary embolism, and adult respiratory distress syndrome.

Discussion and Conclusion: Based on an analysis of 803,949 patients undergoing corrective spine surgery, the overall in-hospital mortality rate is 0.13%. This rate increases with more invasive procedures and higher-risk patients. These findings may aid in counseling patients and improving the safety of care.