Introduction: LLF is a commonly performed spine procedure used to treat degenerative spine disorders and deformities by decompressing and stabilizing the lumbar spine. American Society of Anesthesiologists (ASA) physical status classification system was developed to estimate preoperative health, and is indicative of a patient’s medical complexity. Spinal fusion accounts for the highest hospital costs of any surgical procedure performed in the US, and ASA status has been shown to be a risk factor for cost and length of stay in the orthopedic literature. There is a paucity of literature that directly addresses the influence of ASA status on cost and length of stay following lumbar laminectomy and fusion.

Methods: An institutional database was utilized to identify patients undergoing lumbar laminectomy and fusion between 2006 and 2016. Univariate comparisons between groups were made using chi-squared tests for categorical variables and t-tests for continuous variables. Multivariate linear regression was utilized to estimate regression coefficients, and to determine whether ASA status is an independent risk factor for cost and length of stay following LLF.

Results: 1,849 patients met inclusion criteria. For every one-point increase in ASA score, ICU length of stay increased by 0.518 days (CI: 0.391-0.646, P<0.001), and hospital length of stay increased by 1.93 days (CI: 1.56-2.29, P<0.001). For every one-point increase in ASA score, direct cost increased by $7,474.62 (CI: 5,861.31-9,087.92, P<0.001) (Table 1).

Conclusions: ASA status was a predictor of hospital length of stay, ICU length of stay, and direct cost. Consideration of the ways in which ASA status contributes to increased cost and prolonged length of stay can allow for more accurate reimbursement adjustment as well as more precise targeting of efficiency and cost effectiveness initiatives in the future.

Patient Care: Consideration of the ways in which ASA status contributes to increased cost and prolonged length of stay can allow for more accurate reimbursement adjustment as well as more precise targeting of efficiency and cost effectiveness initiatives in the future.

Learning Objectives: By the end of this session, participants should be able to understand the costs associated with ASA class, and to determine the extent to which ASA status is a predictor of increased cost and length of stay following lumbar laminectomy and fusion (LLF).

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