Spinal versus General Anesthesia in Contemporary Revision Total Hip Arthroplasties.

INTRODUCTION: Spinal anesthesia is increasingly used in complex patient populations including revision total hip arthroplasties (THAs). This study aimed to investigate the pain control, length of stay (LOS), and complications associated with spinal versus general anesthesia in a large institutional series of revision THAs.

METHODS: We retrospectively identified 4,767 revision THAs (4,533 patients) from 2001 to 2016 using our institutional total joint registry. Of these cases, 86% had general and 14% had spinal anesthesia. Demographics between groups were similar with mean age of 66 years, 52% women, and mean BMI of 29. Complications including all-cause re-revisions and reoperations were studied. Data were analyzed using an inverse probability of treatment weighted model based on propensity score that accounted for patient and surgical factors. The mean follow-up was 7 years.

RESULTS: Patients treated with spinal anesthesia required fewer postoperative oral morphine equivalents (OMEs) (P<0.001) and had lower numeric pain rating scale scores (P<0.001). Spinal anesthesia had a decreased LOS (4.2 vs. 4.8 days; P=0.007), fewer cases of altered mental status (AMS; Odds Ratio (OR) 3.1, P=0.001), fewer blood transfusions (OR 2.3, P<0.001), fewer intensive care unit (ICU) admissions (OR 2.3, P<0.001), fewer re-revisions (OR 1.6, P=0.04), and fewer reoperations (OR 1.5, P=0.02).

DISCUSSION: Spinal anesthesia was associated with lower OME use and reduced LOS in this large cohort of revision THAs. Furthermore, spinal anesthesia was associated with fewer cases of AMS, transfusion, ICU admission, re-revision, and reoperation after accounting for numerous patient and operative factors.