Comparison of Staged vs Same-Day Circumferential Spinal Fusions for Adult Spinal Deformity

Abstract

Background: Patients often undergo circumferential (anterior and posterior) spinal fusions to maximize adult spinal deformity (ASD) correction and achieve adequate fusion. Currently, such procedures are performed in staged (ST) or same-day (SD) procedures with limited evidence to support either strategy. This study aims to compare perioperative outcomes and costs of ST vs SD circumferential ASD corrective surgeries.

Methods: This is a retrospective review of patients undergoing circumferential ASD surgeries between 2013 and 2018 in a single institution. Patient characteristics, preoperative comorbidities, surgical details, perioperative complications, readmissions, total hospital admission costs, and 90-day postoperative care costs were identified. All variables were tested for differences between ST and SD groups unadjusted and after applying inverse probability weighting (IPW), and the results before and after IPW were compared.

Results: The entire cohort included a total of 211 (ST = 50, SD = 161) patients, 100 of whom (ST = 44, SD = 56) underwent more than 4 levels fused posteriorly and anterior lumbar interbody fusion (ALIF). Although patient characteristics and comorbidities were not dissimilar between the ST and SD groups, both the number of levels fused in ALIF and posterior spinal fusion (PSF) were significantly different. Thus, using IPW, we were able to minimize the cohort incongruities in the number of levels fused in ALIF and PSF while maintaining comparable patient characteristics. In both the whole cohort and the long segment fusions, postoperative pulmonary embolism was more common in ST procedures. After adjustment utilizing IPW, both groups were not significantly different in disposition, 30-day readmissions, and reoperations. However, within the whole cohort and the long segment fusion cohort, the ST group continued to show significantly increased rates of pulmonary embolism, longer length of stay, and higher hospital admission costs compared with the SD group.

Conclusions: Adjusted comparisons between ST and SD groups showed staging associated with significantly increased length of stay, risk of pulmonary embolism, and admission costs.

Keywords: adult spinal deformity; circumferential fusion; deformity; spinal fusion; staged surgery; staging.

Figure 1

Postoperative complications. In the whole cohort, the staged (ST) group had more complications compared with the same-day (SD) group in the univariate analysis (OR 2.97, P = 0.001) and significantly higher incidence of postoperative pulmonary embolism (PE), altered mental status or delirium, cardiac arrhythmia, and surgical site infections. There were 63 patients (63%) with a postoperative complication within the long segment cohort with no difference between ST and SD groups on unadjusted analysis. Abbreviations: AMS, altered mental status; DVT, deep venous thrombosis; IPW, inverse probability weighting; LE, lower extremity; LS, long segment; PE, pulmonary embolism; SNF, skilled nursing facility; TIA, transient ischemic attack.

Figure 2

Postoperative PE. Using IPW, the rate of PE was significantly higher in staged (ST) vs same-day (SD) groups in the whole cohort (12% vs 1.2%, P = 0.045). In the long segment cohort, there was a significant difference in the rate of postoperative PE in the ST vs SD group (OR = 13.0, P = 0.24). Abbreviations: DVT, deep venous thrombosis; IPW, inverse probability weighting; LS, long segment; PE, pulmonary embolism.

Figure 3

Length of Stay: In both unadjusted and IPW analyses, the length of stay for the staged (ST) group was longer than the same-day (SD) group (10.8 vs 64.8 days), and the ST group was expected to have length of stay 2.2 times longer than the SD group (P < 0.0001) in the whole cohort. In the long segment cohort, on both unadjusted and IPW analyses, we observed a longer length of stay for the ST group than the SD group (10.5 vs 6.2 days), and the ST group was expected to have length of stay 1.7 times longer than the SD group (P < 0.0001). Abbreviations: IPW, inverse probability weighting; LS, long segment.

Figure 4

Hospital costs. Within the whole cohort, the mean cost for same-day (SD) patients was $71,193 compared with $145,907 for staged (ST) patients. For the unadjusted analysis, the average cost was 1.9 times greater in the ST group vs SD group (95% CI 1.6008, 2.2698, P < 0.0001). On IPW, the average cost was 1.6 times greater in the ST group (95% CI 1.0733, 2.2887, P = 0.0203). The mean cost for SD patients with more than 4 levels fused was $93,267.67 compared with $153,481.20 for staged patients. The average cost for the ST group was 1.5 times greater than in the SD group (95% CI 1.2169, 1.8182, P = 0.0002). This significance was again seen using IPW with the average cost being 1.5 times greater in the ST group (95% CI 1.1730, 1.8728, P = 0.0013). Abbreviations: IPW, inverse probability weighting; LS, long segment.