The cost-utility of intraoperative tranexamic acid in adult spinal deformity patients undergoing long posterior spinal fusion.

PURPOSE: This study aims to evaluate the cost-utility of intraoperative tranexamic acid (TXA) in adult spinal deformity (ASD) patients undergoing long posterior (≥ 5 vertebral levels) spinal fusion. METHODS: A decision-analysis model was built for a hypothetical 60-year-old adult patient with spinal deformity undergoing long posterior spinal fusion. A comprehensive review of the literature was performed to obtain event probabilities, costs and health utilities at each node. Health utilities were utilized to calculate Quality-Adjusted Life Years (QALYs). A base-case analysis was carried out to obtain the incremental cost and effectiveness of intraoperative TXA. Probabilistic sensitivity analysis was performed to evaluate uncertainty in our model and obtain mean incremental costs, effectiveness, and net monetary benefits. One-way sensitivity analyses were also performed to identify the variables with the most impact on our model. RESULTS: Use of intraoperative TXA was the favored strategy in 88% of the iterations. The mean incremental utility ratio for using intraoperative TXA demonstrated higher benefit and lower cost while being lower than the willingness-to-pay threshold set at $50,000 per quality adjusted life years. Use of intraoperative TXA was associated with a mean incremental net monetary benefit (INMB) of $3743 (95% CI 3492-3995). One-way sensitivity analysis reported cost of blood transfusions due to post-operative anemia to be a major driver of cost-utility analysis. CONCLUSION: Use of intraoperative TXAs is a cost-effective strategy to reduce overall perioperative costs related to post-operative blood transfusions. Administration of intraoperative TXA should be considered for long fusions in ASD population when not explicitly contra-indicated due to patient factors.

Adult spinal deformity surgery: the effect of surgical start time on patient outcomes and cost of care.

PURPOSE: There are reports investigating the effect of surgical start time (SST) on outcomes, length of stay (LOS) and cost in various surgical disciplines. However, this has not been studied in spine deformity surgery to date. This study compares outcomes for patients undergoing spinal deformity surgery based on SST. METHODS: Patients at a single academic institution from 2008 to 2016 undergoing elective spinal deformity surgery (defined as fusing ≥ 7 segments) were divided by SST before or after 2 PM. Co-primary outcomes were LOS and direct costs. Secondary outcomes included delayed extubation, ICU stay, complications, reoperation, non-home discharge, and readmission rates. RESULTS: There were 373 surgeries starting before 2 PM and 79 after 2 PM. The cohorts had similar demographics including age, sex, comorbidity burden, and levels fused. The late SST cohort had shorter operation durations (p = 0.0007). Multivariable linear regression showed no differences in LOS (estimate 0.4 days, CI - 1.2 to 2.0, p = 0.64) or direct cost (estimate $3652, 95% CI - $1449 to $8755, p = 0.16). Multivariable logistic regression revealed the late SST cohort was more likely to have delayed extubation (OR 2.6, 95% CI 1.4-4.9, p = 0.004) and non-home discharge (OR 2.2, 95% CI 1.1-4.2, p = 0.03). All other secondary outcomes were non-significant. CONCLUSION: Patients undergoing spinal deformity surgery before and after 2 PM have similar LOS and cost of care. However, the late SST cohort had increased likelihood of delayed extubation and non-home discharges, which increase cost in bundled payment models. These findings can be utilized in OR scheduling to optimize outcomes and minimize cost.

Inpatient versus outpatient halo-gravity traction in children with severe spinal deformity.

STUDY DESIGN: A retrospective, comparative study. OBJECTIVE: To compare the results, complications, and costs of preoperative halo-gravity traction in in- and outpatient settings. BACKGROUND DATA: Surgical management of severe spinal deformities remains complex and controversial. Preoperative halo-gravity traction results in a decreased need for aggressive surgical techniques, lower incidence of intraoperative neurologic complications, and improvement of nutritional parameters and preoperative cardiopulmonary function. METHODS: Twenty-nine patients younger than 18 years with kyphoscoliosis undergoing preoperative halo-gravity traction were divided into two groups: inpatients (n: 15) and outpatients (n: 14, home care or care at the Foundation). Traction time (weeks), traction weight (kg), radiographic curve correction, complications, and costs were compared. For statistical analysis, t test and odds ratio were calculated with a significance of p < 0.05. RESULTS: Mean traction time was 6 weeks for in- and 4 weeks for outpatients (p = 0.038). Initial traction weight was 6 kg in both groups, while final traction weight was 13 kg for in- and 15 kg for outpatients (p = 0.50). At the end of the traction period, coronal correction was 24° in in- and 28° in outpatients (p = 0.5), while sagittal correction was 27° and 29°, respectively (p = 0.80). Pin loosening was observed in 2 patients in each group, of whom 1 outpatient developed pin-site infection. In each group, one patient developed transient neurologic complications (odds ratio 1.091). Mean treatment cost per patient was 2.8-fold higher in inpatients. CONCLUSIONS: Considering complications and costs, our results show that preoperative halo-gravity traction in an outpatient setting is an option to be taken into account. LEVEL OF EVIDENCE: Grade III.

Cost-Utility Analysis of rhBMP-2 Use in Adult Spinal Deformity Surgery.

STUDY DESIGN: Economic modeling of data from a multicenter, prospective registry. OBJECTIVE: The aim of this study was to analyze the cost utility of recombinant human bone morphogenetic protein-2 (BMP) in adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND DATA: ASD surgery is expensive and presents risk of major complications. BMP is frequently used off-label to reduce the risk of pseudarthrosis. METHODS: Of 522 ASD patients with fusion of five or more spinal levels, 367 (70%) had at least 2-year follow-up. Total direct cost was calculated by adding direct costs of the index surgery and any subsequent reoperations or readmissions. Cumulative quality-adjusted life years (QALYs) gained were calculated from the change in preoperative to final follow-up SF-6D health utility score. A decision-analysis model comparing BMP versus no-BMP was developed with pseudarthrosis as the primary outcome. Costs and benefits were discounted at 3%. Probabilistic sensitivity analysis was performed using mixed first-order and second-order Monte Carlo simulations. One-way sensitivity analyses were performed by varying cost, probability, and QALY estimates (Alpha = 0.05). RESULTS: BMP was used in the index surgery for 267 patients (73%). The mean (±standard deviation) direct cost of BMP for the index surgery was $14,000 ±â€Š$6400. Forty patients (11%) underwent revision surgery for symptomatic pseudarthrosis (BMP group, 8.6%; no-BMP group, 17%; P = 0.022). The mean 2-year direct cost was significantly higher for patients with pseudarthrosis ($138,000 ±â€Š$17,000) than for patients without pseudarthrosis ($61,000 ±â€Š$25,000) (P < 0.001). Simulation analysis revealed that BMP was associated with positive incremental utility in 67% of patients and considered favorable at a willingness-to-pay threshold of $150,000/QALY in >52% of patients. CONCLUSION: BMP use was associated with reduction in revisions for symptomatic pseudarthrosis in ASD surgery. Cost-utility analysis suggests that BMP use may be favored in ASD surgery; however, this determination requires further research. LEVEL OF EVIDENCE: 2.

Metabolic Syndrome has a Negative Impact on Cost Utility Following Spine Surgery.

OBJECTIVE: Investigate the differences in spine surgery cost for metabolic syndrome patients. METHODS: Included were patients ≥18 undergoing fusion. Patients were divided into cervical, thoracic, and lumbar groups based on their upper instrumented vertebrae (UIV). Metabolic syndrome patients (MetS) included those with body mass index >30, diabetes mellitus, dyslipidemia, and hypertension. Propensity score matching for invasiveness between non-MetS and MetS used to assess cost differences. Total surgery costs for MetS and non-MetS adult spinal deformity patients were compared. Quality-adjusted life years (QALYs) and cost per QALY for UIV groups were calculated. RESULTS: A total of 312 invasiveness matched surgeries met inclusion criteria. Baseline demographics and surgical details included age 57.7 ± 14.5, 54% female, body mass index 31.1 ± 6.6, 17% anterior approach, 70% posterior approach, 13% combined approach, and 3.8 ± 4.1 levels fused. The average costs of surgery between MetS and non-Mets patients was $60,579.30 versus $52,053.23 (P < 0.05). When costs were compared between UIV groups, MetS patients had higher cervical and thoracic surgery costs ($23,203.43 vs. $19,153.43, $75,230.05 vs. $65,746.16, all P < 0.05) and lower lumbar costs ($31,775.64 vs. $42,643.37, P < 0.05). However, the average cost per QALY at 1 year was $639,069.32 for MetS patients and $425,840.30 for non-Mets patients (P < 0.05). At life expectancy, the cost per QALY was $45,456.83 versus $26,026.84 (P < 0.05). CONCLUSIONS: When matched by invasiveness, MetS patients had an average 16.4% higher surgery costs, 50% higher costs per QALY at 1 year, and 75% higher cost per QALY at life expectancy. Further research is needed on the possible utility of reducing comorbidities in preoperative patients.

Cost-Effectiveness of a Radio Frequency Hemostatic Sealer (RFHS) in Adult Spinal Deformity Surgery.

BACKGROUND: Patients undergoing posterior spinal fusion surgery can lose a substantial amount of blood. This can prolong operative time and require transfusion of allogeneic blood components, which increases the risk of infection and can be the harbinger of serious complications. Does a saline-irrigated bipolar radiofrequency hemostatic sealer (RFHS) help reduce transfusion requirements? METHODS: In an observational cohort study, we compared transfusion requirements in 30 patients undergoing surgery for adult spinal deformity using the RFHS with that of a historical control group of 30 patients in which traditional hemostasis was obtained with bipolar electrocautery and matched them for blood loss-related variables. Total expense to the hospital for the RFHS, laboratory expenses, and blood transfusions was used for cost calculations. The incremental cost-effectiveness ratio was calculated using the number of blood transfusions avoided as the effectiveness payoff. RESULTS: Using a multivariable linear regression model, we found that only estimated blood loss (EBL) was an independent significant predictor of transfusion requirement in both groups. We evaluated the variables of age, EBL, time duration of surgery, preoperative hemoglobin, hemoglobin nadir during surgery, body mass index, length of stay, and number of levels operated on. Mean EBL was greater in the control group (2201 vs. 1416 mL, P = 0.0099). The number of transfusions also was greater in the control group (14.5 vs. 6.5, P = 0.0008). In the cost-effectiveness analysis, we found that the RFHS cost $108 more (compared with not using the RFHS) to avoid 1 unit of blood transfusion. CONCLUSIONS: The cost-effectiveness analysis revealed that if we are willing to pay $108 to avoid 1 unit of blood transfusion, the use of the RFHS is a reasonable choice to use in open surgery for adult spinal deformity.

Center variation in episode-of-care costs for adult spinal deformity surgery: results from a prospective, multicenter database.

BACKGROUND CONTEXT: Adult spinal deformity (ASD) surgery is associated with significant resource utilization, costing more than $958 million in charges for Medicare patients and more than $1.7 billion in charges for managed care population in the last decade. Given the recent move toward bundled payment models, it is important to understand the various care components a patient receives over the course of a defined clinical episode, its associated cost, and the proportion of cost for each component toward the bundled payment. PURPOSE: To examine the degree and determinants of variation in inpatient episode-of-care (EOC) cost, resource utilization, and patient-reported outcomes for patients undergoing ASD surgery across four spine deformity centers in the United States. STUDY DESIGN/SETTING: Retrospective analysis of prospective, multicenter database. PATIENT SAMPLE: Consecutive patients enrolled in an ASD database from four spinal deformity centers. OUTCOME MEASURES: Total in-patient EOC costs and Short Form (SF)-6D. METHODS: The study used a multicenter database of 210 consecutively enrolled operative patients from 2008 to 2013 at four participating centers in the United States. Demographic, surgical, and direct cost data, expressed in 2013 dollars, for the entire inpatient EOC were obtained from administrative databases from the respective hospitals. Mixed models and multivariable linear regression were used to evaluate the impact of center on total costs adjusting for patient characteristics, length of stay (LOS), and surgical factors. RESULTS: A total of 126 patients with complete baseline and 2-year follow-up data were included. The percentages of patients from each center were 36.5%, 7.1%, 24.6%, and 31.7%. Overall, the mean patient age was 58.4±12.6 years, 86% were women, and 94% were Caucasian. The proportion of total cost variation explained by the center at which the patient was treated was 17%. After adjusting for patient, LOS, and surgical factors the cost variation reduced to 4%. In multivariable analysis, each additional level fused increased total cost variation by $2,500, whereas recombinant human bone morphogenetic protein-2 (BMP) use and posterior-only surgical approach lowered total EOC costs by $10,500 and $9,400, respectively. No significant difference was observed in 2-year quality-adjusted life year across centers. CONCLUSIONS: Total EOC costs for ASD surgery varied significantly by center. Levels fused, BMP use, and surgical approach were the primary drivers of cost variation across centers. Differences in resource utilization had no impact on 2-year quality-adjusted life year improvement across centers.

Cost-utility analysis of cervical deformity surgeries using 1-year outcome.

BACKGROUND CONTEXT: Cost-utility analysis, a special case of cost-effectiveness analysis, estimates the ratio between the cost of an intervention to the benefit it produces in number of quality-adjusted life years. Cervical deformity correction has not been evaluated in terms of cost-utility and in the context of value-based health care. Our objective, therefore, was to determine the cost-utility ratio of cervical deformity correction. STUDY DESIGN: This is a retrospective review of a prospective, multicenter cervical deformity database. Patients with 1-year follow-up after surgical correction for cervical deformity were included. Cervical deformity was defined as the presence of at least one of the following: kyphosis (C2-C7 Cobb angle >10°), cervical scoliosis (coronal Cobb angle >10°), positive cervical sagittal malalignment (C2-C7 sagittal vertical axis >4 cm or T1-C6 >10°), or horizontal gaze impairment (chin-brow vertical angle >25°). Quality-adjusted life years were calculated by both EuroQol 5D (EQ5D) quality of life and Neck Disability Index (NDI) mapped to short form six dimensions (SF6D) index. Costs were assigned using Medicare 1-year average reimbursement for: 9+ level posterior fusions (PF), 4-8 level PF, 4-8 level PF with anterior fusion (AF), 2-3 level PF with AF, 4-8 level AF, and 4-8 level posterior refusion. Reoperations and deaths were added to cost and subtracted from utility, respectively. Quality-adjusted life year per dollar spent was calculated using standardized methodology at 1-year time point and subsequent time points relying on maintenance of 1-year utility. RESULTS: Eighty-four patients (average age: 61.2 years, 60% female, body mass index [BMI]: 30.1) were analyzed after cervical deformity correction (average levels fused: 7.2, osteotomy used: 50%). Costs associated with index procedures were 9+ level PF ($76,617), 4-8 level PF ($40,596), 4-8 level PF with AF ($67,098), 4-8 level AF ($31,392), and 4-8 level posterior refusion ($35,371). Average 1-year reimbursement of surgery was $55,097 at 1 year with eight revisions and three deaths accounted for. Cost per quality-adjusted life year (QALY) gained to 1-year follow-up was $646,958 by EQ5D and $477,316 by NDI SF6D. If 1-year benefit is sustained, upper threshold of cost-effectiveness is reached 3-4.5 years after intervention. CONCLUSIONS: Medicare 1-year average reimbursement compared with 1-year QALYdescribed $646,958 by EQ5D and $477,316 by NDI SF6D. Cervical deformity surgeries reach accepted cost-effectiveness thresholds when benefit is sustained 3-4.5 years. Longer follow-up is needed for a more definitive cost-analysis, but these data are an important first step in justifying cost-utility ratio for cervical deformity correction.

A cost-effectiveness comparisons of adult spinal deformity surgery in the United States and Japan.

PURPOSE: Information about the cost-effectiveness of surgical procedures for adult spinal deformity (ASD) is critical for providing appropriate treatments for these patients. The purposes of this study were to compare the direct cost and cost-effectiveness of surgery for ASD in the United States (US) and Japan (JP). METHODS: Retrospective analysis of 76 US and 76 JP patients receiving surgery for ASD with ≥2-year follow-up was identified. Data analysis included preoperative and postoperative demographic, radiographic, health-related quality of life (HRQOL), and direct cost for surgery. An incremental cost-effectiveness ratio (ICER) was determined using cost/quality-adjusted life years (QALY). The cost/QALY was calculated from the 2-year cost and HRQOL data. RESULTS: JP exhibited worse baseline spinopelvic alignment than the US (pelvic incidence and lumbar lordosis: 35.4° vs 22.7°, p < 0.01). The US had more three-column osteotomies (50 vs 16%), and shorter hospital stay (7.9 vs 22.7 days) (p < 0.05). The US demonstrated worse postoperative ODI (41.3 vs. 33.9%) and greater revision surgery rate (40 vs 10%) (p < 0.05). Due to the high initial cost and revision frequency, the US had greater total cost ($92,133 vs. $49,647) and cost/QALY ($511,840 vs. $225,668) at 2-year follow-up (p < 0.05). CONCLUSION: Retrospective analysis comparing the direct costs and cost-effectiveness of ASD surgery in the US vs JP demonstrated that the total direct costs and cost/QALY were substantially higher in the US than JP. Variations in patient cohort, healthcare costs, revision frequencies, and HRQOL improvement influenced the cost/QALY differential between these countries.

Cost-Effectiveness of Primary and Revision Surgery for Adult Spinal Deformity.

STUDY DESIGN: Retrospective comparative study. OBJECTIVE: The purpose of this study is to compare functional outcomes, hospital resource utilization, and spine-related costs during 2 years in patients who had undergone primary or revision surgery for adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA: After surgery for ASD, patients may require revision for pseudarthrosis, implant complications, or deformity progression. Data evaluating cost-effectiveness of primary and, in particular, revision surgery, for ASD are sparse. METHODS: We retrospectively reviewed records for 119 consecutive patients who had undergone primary or revision surgery for ASD. Two-year total spine-related medical costs were derived from hospital charge data. Functional outcome scores were extracted from prospectively collected patient data. Cost utility ratios (cost/quality-adjusted life-year [QALY]) at 2 years were calculated and assessed against a threshold of $154,458/QALY gained (three times the 2015 US per-capita gross domestic product). RESULTS: The primary surgery cohort (n = 56) and revision cohort (n = 63) showed significant improvements in health-related quality-of-life scores at 2 years. Median surgical and spine-related 2-year follow-up costs were $137,990 (interquartile range [IQR], $84,186) for primary surgery and $115,509 (IQR, $63,753) for revision surgery and were not significantly different between the two groups (P = 0.12). We report 2-year QALY gains of 0.36 in the primary surgery cohort and 0.40 in the revision group (P = 0.71). Primary instrumented fusion was associated with a median 2-year cost per QALY of $197,809 (IQR, $187,350) versus $129,950 (IQR, $209,928) for revision surgery (P = 0.31). CONCLUSION: Revision surgery had lower total 2-year costs and higher QALY gains than primary surgery for ASD, although the differences were not significant. Although revision surgery for ASD is known to be technically challenging and to have a higher rate of major complications than primary surgery, revision surgery was cost-effective at 2 years. The cost/QALY ratio for primary surgery for ASD exceeded the threshold for cost effectiveness at 2 years. LEVEL OF EVIDENCE: 3.

Impact of cost valuation on cost-effectiveness in adult spine deformity surgery.

BACKGROUND CONTEXT: Over the past decade, the number of adult spinal deformity (ASD) surgeries has more than doubled in the United States. The complex surgeries needed to manage ASD are associated with significant resource utilization and high cost, making them a primary target for increased scrutiny. Accordingly, it is important to not only demonstrate value in ASD surgery as clinical effectiveness but also to translate outcome assessment to cost-effectiveness. PURPOSE: To compare the difference between Medicare allowable rates and the actual, direct hospital costs for ASD surgeries. STUDY DESIGN: Longitudinal cohort. PATIENT SAMPLE: Consecutive patients enrolled in an ASD database from a single institution. OUTCOME MEASURES: Short Form (SF)-6D. METHODS: Consecutive patients enrolled in an ASD database from a single institution from 2008 to 2013 were identified. Direct hospital costs were collected from hospital administrative records for the entire inpatient episode of surgical care. Medicare allowable rates were calculated for the same inpatient stays using the year-appropriate Center for Medicare-Medicaid Services Inpatient Pricer Payment System Tool. The SF-6D, a utility index derived from the SF-36v1, was used to determine quality-adjusted life years (QALY). Costs and QALYs were discounted at 3.5% annually. RESULTS: Of 580 surgical ASD patients eligible for 2-year follow up, 346 (60%) had complete baseline and 2-year data, and 60 were Medicare beneficiaries comprising the cohort for the present study. Mean SF-6D gained is 0.10 during year 1 after surgery and 0.02 at year 2, resulting in a cumulative SF-6D gain of 0.12 over 2 years. Mean Medicare allowable rate over the 2 years is $82,050 (range $42,383 to $220,749) and mean direct cost is $99,114 (range $28,447 to $217,717). Mean cost per QALY over 2 years is $683,750 using Medicare allowable rates and $825,950 using direct costs. This difference of $17,181 between the 2 cost calculation represents a 17% difference, which was statistically significant (p<.001). CONCLUSIONS: There is a significant difference in direct hospital costs versus Medicare allowable rates in ASD surgery and in turn, there is a similar difference in the cost per QALY calculation. Utilizing Medicare allowable rates not only underestimates (17%) the cost of ASD surgery, but it also creates inaccurate and unrealistic expectations for researchers and policymakers.