Red Blood Cell Transfusion Need for Elective Primary Posterior Lumbar Fusion in A High-Volume Center for Spine Surgery

Budget Impact Analysis of Minimally Invasive versus Open Transforaminal Lumbar Interbody Fusion for Lumbar Degenerative Disease: A European Hospital Perspective

Purpose

When traditional therapies fail to provide relief from debilitating lower back pain, surgeries such as transforaminal lumbar interbody fusion (TLIF) may be required. This budget impact analysis (BIA) compared minimally-invasive (MI)-TLIF versus open (O)-TLIF for single-level fusion from an Italian hospital perspective.

Methods

The BIA compared costs of 100 MI-TLIF and 100 O-TLIF procedures from an Italian hospital perspective over a one-year time horizon. The base case included costs for length of hospital stay (LOS), blood loss, and sterilizing surgical trays. The scenario analysis also included operating room (OR) time and complication costs. Base case inputs were from the Miller et al meta-analysis; scenario analysis inputs were from the Hammad et al meta-analysis. The device costs for MI-TLIF and O-TLIF procedures were from Italian tender prices for Viper Prime™ System and Expedium™ Spine System, respectively.

Results

Base case deterministic analysis results showed cost savings of €207,370 for MI-TLIF compared with O-TLIF. MI-TLIF costs were lower for LOS (€215,277), transfusion for blood loss (€16,881), and surgical tray sterilization (€28,232), whereas device costs were lower for O-TLIF (€53,020). The probabilistic result was similar, with MI-TLIF resulting in savings of €211,026 (95% credible interval [CR]: €208,725 - €213,327). All 1000 base case probabilistic sensitivity analysis runs were cost saving. Deterministic scenario analysis results showed cost savings of €166,719 for MI-TLIF. MI-TLIF costs were lower for LOS (€190,813), transfusion for blood loss (€16,881), surgical tray sterilization (€28,232), and complications (€2076), whereas O-TLIF costs were lower for OR time (€18,263) and devices used (€53,020).

Conclusion

Despite the increase incremental cost for medical device innovation and OR time, this study demonstrates the economic savings of MI-TLIF compared to O-TLIF from a European hospital perspective. The findings will be useful to policy and hospital decision makers in assessing purchasing, funding and reimbursement decisions.

Predictive modeling of perioperative blood transfusion in lumbar posterior interbody fusion using machine learning

Background: Accurate estimation of perioperative blood transfusion risk in lumbar posterior interbody fusion is essential to reduce the number, cost, and complications associated with blood transfusions. Machine learning algorithms have the potential to outperform traditional prediction methods in predicting perioperative blood transfusion. This study aimed to construct a machine learning-based perioperative transfusion risk prediction model for lumbar posterior interbody fusion in order to improve the efficacy of surgical decision-making. Methods: We retrospectively collected clinical data on 1905 patients who underwent lumbar posterior interbody fusion surgery at the Second Hospital of Shanxi Medical University between January 2021 and March 2023. All the data was randomly divided into a training set and a validation set, and the "feature_importances" method provided by eXtreme Gradient Boosting (XGBoost) algorithm was applied to select statistically significant features on the training set to establish five machine learning prediction models. The optimal model was identified by utilizing the area under the curve (AUC) and the probability calibration curve on the validation set. Shapley additive explanations (SHAP) and local interpretable model-agnostic explanations (LIME) were employed for interpretable analysis of the optimal model. Results: In the postoperative outcomes of patients, the number of hospital days in the transfusion group was longer than that in the non-transfusion group. Additionally, the transfusion group experienced higher total hospital costs, 90-day readmission rates, and complication rates within 90 days after surgery than the non-transfusion group. A total of 9 features were selected for the models. The XGBoost model performed best with an AUC value of 0.958. The SHAP values showed that intraoperative blood loss, intraoperative fluid infusion, and number of fused segments were the top 3 most important features affecting perioperative blood transfusion in lumbar posterior interbody fusion. The LIME algorithm was used to interpret the individualized prediction. Conclusion: Surgery, ASA class, levels fused, total intraoperative blood loss, operative time, and preoperative Hb are viable predictors of perioperative blood transfusion in lumbar posterior interbody fusion. The XGBoost model has demonstrated superior predictive efficacy compared to the traditional logistic regression model, making it a more effective decision-making tool for perioperative blood transfusion.

Risk Factors for Significant Intraoperative Blood Loss during Anterior Cervical Decompression and Fusion for Degenerative Cervical Diseases

OBJECTIVES

Anterior cervical decompression and fusion (ACF) has become a widely accepted surgical treatment for degenerative cervical diseases, but occasionally, significant intraoperative blood loss (SIBL), which is defined as IBL of 500 mL or more, will occur. We aimed to investigate the independent risk factors for SIBL during ACF for degenerative cervical diseases.

METHODS

We enrolled 1150 patients who underwent ACF for degenerative cervical diseases at our hospital between 2013 and 2019. The patients were divided into two groups: the SIBL group (n = 38) and the non-SIBL group (n = 1112). Demographic, surgical and radiographic data were recorded prospectively to investigate the independent risk factors for SIBL. For counting data, the chi-square test or Fisher's exact probability test was used. Student's t-test or the Mann-Whitney rank sum test was used for comparisons between groups of measurement data. Univariate analysis and multivariate logistic regression analysis were further used to analyze the significance of potential risk factors.

RESULTS

The incidence of SIBL during ACF was 3.3% (38/1150). A multivariate analysis revealed that female sex (odds ratio [OR], 6.285; 95% confidence interval [CI], 2.707-14.595; p < 0.001), corpectomy (OR, 3.872; 95% CI, 1.616-9.275; p = 0.002), duration of operation ≥150 min (OR, 8.899; 95% CI, 4.042-19.590; p < 0.001), C3 involvement (OR, 4.116; 95% CI, 1.808-9.369; p = 0.001) and ossification of posterior longitudinal ligament (OPLL) at the surgical level (OR, 6.007; 95% CI, 2.218-16.270; p < 0.001) were independent risk factors for SIBL. Patients with SIBL had more days of first-degree/intensive nursing (p = 0.003), longer length of stay (p = 0.003) and higher hospitalization costs (p = 0.023).

CONCLUSION

Female sex, corpectomy, duration of operation, C3 involvement and OPLL at the surgical level were independent risk factors for SIBL during ACF. SIBL in ACF was associated with more days of first-degree/intensive nursing, longer length of stay and higher hospitalization costs.

Development and validation of a novel nomogram to predict the risk of the prolonged postoperative length of stay for lumbar spinal stenosis patients

BACKGROUND

Lumber spinal stenosis (LSS) is the increasingly reason for spine surgery for elder patients since China is facing the fastest-growing aging population. The aim of this research was to create a model to predict the probabilities of requiring a prolonged postoperative length of stay (PLOS) for lumbar spinal stenosis patients, minimizing the healthcare burden.

METHODS

A total of 540 LSS patients were enrolled in this project. The outcome was a prolonged PLOS after spine surgery, defined as hospitalizations ≥ 75th percentile for PLOS, including the day of discharge. The least absolute shrinkage and selection operator (LASSO) was used to identify independent risk variables related to prolonged PLOS. Multivariable logistic regression analysis was utilized to generate a prediction model utilizing the variables employed in the LASSO approach. The receiver operating characteristic (ROC) curve's area under the curve (AUC) and the calibration curve's respective curves were used to further validate the model's calibration with predictability and discriminative capabilities. By using decision curve analysis, the resulting model's clinical effectiveness was assessed.

RESULTS

Among 540 individuals, 344 had PLOS that was within the usual range of P75 (8 days), according to the interquartile range of PLOS, and 196 had PLOS that was above the normal range of P75 (prolonged PLOS). Four variables were incorporated into the predictive model, named: transfusion, operation duration, blood loss and involved spine segments. A great difference in clinical scores can be found between the two groups (P < 0.001). In the development set, the model's AUC for predicting prolonged PLOS was 0.812 (95% CI: 0.768-0.859), while in the validation set, it was 0.830 (95% CI: 0.753-0.881). The calibration plots for the probability showed coherence between the expected probability and the actual probability both in the development set and validation set respectively. When intervention was chosen at the potential threshold of 2%, analysis of the decision curve revealed that the model was more clinically effective.

CONCLUSIONS

The individualized prediction nomogram incorporating five common clinical features for LSS patients undergoing surgery can be suitably used to smooth early identification and improve screening of patients at higher risk of prolonged PLOS and minimize health care.

Surgical bleeding in patients undergoing posterior lumbar inter-body fusion surgery: a randomized clinical trial evaluating the effect of two mechanical ventilation mode types

BACKGROUND

The purpose of the study was to compare the effect of using volume-controlled ventilation (VCV) versus pressure-controlled ventilation (PCV) on blood loss in patients undergoing posterior lumbar inter-body fusion (PLIF) surgery.

METHODS

In a randomized, single-blinded, parallel design, 78 patients, candidates for PLIF surgery, were randomly allocated into two groups of 39 to be mechanically ventilated using VCV or PCV mode. All the patients were operated in prone position by one surgeon. Amount of intraoperative surgical bleeding, transfusion requirement, surgeon satisfaction, hemodynamic parameters, heart rate, and blood pressure were measured as outcomes.

RESULTS

PCV group showed slightly better outcomes than VCV group in terms of mean blood loss (431 cc vs. 465 cc), transfusion requirement (0.40 vs. 0.43 unit), and surgeon satisfaction (82.1% vs. 74.4%); however, the differences were not statistically significant. Diastolic blood pressure 90 and 105 min after induction were significantly lower in PCV group (P = 0.043-0.019, respectively); however, blood pressure at other times, hemoglobin levels, and mean heart rate were similar in two groups.

CONCLUSIONS

In patients undergoing posterior lumbar inter-body fusion surgery, mode of ventilation cannot make significant difference in terms of blood loss; however, some minor benefits in outcomes may lead to the selection of PCV rather than VCV. More studies with larger sample size, and investigating more factors may be needed.

Demographics and Medical Comorbidities as Risk Factors for Increased Episode of Care Costs Following Lumbar Fusion in Medicare Patients

The objective was to evaluate medical comorbidities and surgical variables as independent risk factors for increased health care costs in Medicare patients undergoing lumbar fusion. Care episodes limited to lumbar fusions were retrospectively reviewed on the Centers of Medicare and Medicaid Innovation (CMMI) Bundled Payment for Care Improvement (BPCI) reimbursement database at a single academic institution. Total episode of care cost was also collected. A multivariable linear regression model was developed to identify independent risk factors for increased total episode of care cost, and logistic models for surgical complications and readmission. A total of 500 Medicare patients were included. Risk factors associated with increased total episode of care cost included transforaminal interbody fusion (TLIF) and anterior lumbar interbody fusion (ALIF) (β = $5,399, P < 0.001) and ALIF+PLF (AP) fusions (β = $24,488, P < 0.001), levels fused (β = $3,989, P < 0.001), congestive heart failure (β = $6,161, P = 0.022), hypertension with end-organ damage (β = $10,138, P < 0.001), liver disease (β = $16,682, P < 0.001), inpatient complications (β = $4,548, P = 0.001), 90-day complications (β = $10,012, P = 0.001), and 90-day readmissions (β = $15,677, P < 0.001). The most common surgical complication was postoperative anemia, which was associated with significantly increased costs (β = $18,478, P < 0.001). Female sex (OR = 2.27, P = 0.001), AP fusion (OR = 2.59, P = 0.002), levels fused (OR = 1.45, P = 0.005), cerebrovascular disease (OR = 4.19, P = 0.003), cardiac arrhythmias (OR = 2.32, P = 0.002), and fluid electrolyte disorders (OR = 4.24, P = 0.002) were independent predictors of surgical complications. Body mass index (OR = 1.07, P = 0.029) and AP fusions (OR = 2.87, P = 0.049) were independent predictors of surgical readmission. Among medical comorbidities, congestive heart failure, hypertension with end-organ damage, and liver disease were independently associated with a significant increase in total episode of care cost. Interbody devices were associated with increased admission cost.

Complications, readmissions, reoperations and patient-reported outcomes in patients with multiple sclerosis undergoing elective spine surgery - a propensity matched analysis

BACKGROUND CONTEXT

Multiple sclerosis (MS) is an autoimmune, neurodegenerative disease that can lead to significant functional disability. Improving treatment regimens have extended life expectancy and led to an increase in the number of elective spine surgeries for degenerative conditions in the MS population. Recent literature has reported mixed results regarding the efficacy of elective spine surgery for patients with MS. There is also a paucity of literature comparing postoperative patient reported outcomes (PROs) and reoperation rates between patients with and without MS.

PURPOSE

To determine if patients with MS have worse PROs and higher complication, readmission and reoperation rates after elective spine surgery compared with patients without neurodegenerative conditions when adjusting for baseline covariates through propensity matching.

STUDY DESIGN/SETTING

Retrospective review of prospectively collected data from the Quality Outcomes Database (QOD), a national, longitudinal, multicenter spine outcomes registry.

PATIENT SAMPLE

For the lumbar cohort, 312 patients with MS and 46,738 patients without MS were included. The cervical myelopathy cohort included 91 patients with MS and 6,426 patients without MS. The cervical radiculopathy cohort consisted of 103 patients with MS and 13,751 patients without MS.

OUTCOME MEASURES

1) complication rates, 2) readmission rates, 3) reoperation rates, and 4) PROs at 3- and 12-months including ODI/NDI, NRS back/neck/arm/leg pain, mJOA scores and patient satisfaction ratings.

METHODS

Data from the QOD was queried for patients with surgeries occurring between 04/2013-01/2019. Three surgical groups were included: 1) Elective lumbar surgery, 2) Elective cervical surgery for myelopathy, 3) Elective cervical surgery for radiculopathy. Patients with any neurodegenerative condition other than MS were excluded. Patients without MS were propensity matched against patients with MS in a 5 to 1 ratio without replacement based on ASA grade, arthrodesis, surgical approach, number of operated levels, age, and baseline ODI/NDI, NRS leg/arm pain, NRS back/neck pain, and EQ-5D. Multivariable regressions with cluster-robust standard errors were used to estimate average effect of how the outcome would change if the MS patient didn't have the disease. The mean difference was used for continuous outcomes and the risk difference was used for binary outcomes.

RESULTS

For the lumbar cohort, no differences were found between the 2 groups at 3 or 12 months in any of the outcome measures. For the myelopathy cohort, patients with MS patients had a lower rate of reoperation at 12 months (risk difference=-0.036, p=.007) and worse 3-month mJOA scores (mean difference=-1.044, p=.004) compared with patients without MS. For the radiculopathy cohort, patients with MS had a lower rate of reoperation at 3 months (risk difference=-0.019, p=.018) and 12 months (risk difference=-0.029, p=.007) compared with those without MS.

CONCLUSIONS

Patients with MS had similar PROs compared with patients without MS when adjusting for baseline covariates through propensity matching, except for 3-month mJOA scores in the myelopathy cohort. Reoperation rates were found to be lower in patients with MS undergoing elective cervical surgery for both myelopathy and radiculopathy. These results suggest that when analyzed independently, a diagnosis of MS does not significantly impact complication, readmission and reoperation rates or PROs, and therefore should not represent a major contraindication to elective spine surgery. Surgical decisions in this patient population should be made based on careful consideration of patient factors including other comorbidities as well as baseline patient functional status.

Transfusion guidelines in adult spine surgery: a systematic review and critical summary of currently available evidence

BACKGROUND CONTEXT

Red blood cell transfusion can be associated with complications in medical and surgical patients. Acute anemia in ambulatory patients undergoing surgery can also impede wound healing and independent self-care. Current transfusion threshold guidelines are still based on evidence derived from critically-ill intensive care unit medical patients and may not apply to spine surgery candidates.

PURPOSE

We aimed to provide the reader with a synthesis of the best available evidence to recommend transfusion trigger thresholds and guidelines in adult patients undergoing spine surgery.

STUDY DESIGN/SETTING

This is a systematic review.

OUTCOME MEASURES

Physiological measure: Blood transfusion thresholds and associated posttransfusion complications (morbidity, mortality, length of stay, infections, etc) of the published articles.

PATIENT SAMPLE

Adult spine surgery patients.

METHODS

A systematic review of the literature using the PubMed, Google Scholar, and Web of Science electronic databases was made according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Focus was set on papers discussing thresholds for blood transfusion in adult surgical spine patients, as well as complications associated with transfusion after acute surgical blood loss in the operating room or postoperative period. Publications discussing pediatric cases, blood type analyses, blood loss prevention strategies and protocols, systematic reviews and letters to the editor were excluded.

RESULTS

A total of 22 articles fitting our search criteria were reviewed. Patients who received blood transfusion in these studies were older, of female gender, had more severe comorbidities except for smoking, and had prolonged surgical time. Blood transfusion was associated with multiple adverse postoperative complications, including a higher rate of superficial or deep surgical site infections, sepsis, urinary and pulmonary infections, cardiovascular complications, return to the operating room, and increased postoperative length of stay and 30 day readmission. Analysis of transfusion thresholds from these studies showed that a pre-operative hemoglobin (Hb) of > 13 g/dL, and an intraoperative and post-operative Hb nadir above 9 and 8 g/dL, respectively, were associated with better outcomes and fewer wound infections than lower thresholds (Level B Class III). Additionally, it was generally recommended to transfuse autologous blood that was < 28 days old, if possible, with a limit of 2 to 3 units to minimize patient morbidity and mortality.

CONCLUSIONS

Blood transfusion thresholds in surgical patients may be specialty-specific and different than those used for critically-ill medical patients. For adult spine surgery patients, red blood cell transfusion should be avoided if Hb numbers remain > 9 and 8 g/dL in the intraoperative and direct post-operative periods, respectively.

Spine Surgery and Preoperative Hemoglobin, Hematocrit, and Hemoglobin A1c: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVES

Synthesize previous studies evaluating clinical utility of preoperative Hb/Hct and HbA1c in patients undergoing common spinal procedures: anterior cervical discectomy and fusion (ACDF), posterior cervical fusion (PCF), posterior lumbar fusion (PLF), and lumbar decompression (LD).

METHODS

We queried PubMed, Embase, Cochrane Library, and Web of Science for literature on preoperative Hb/Hct and HbA1c and post-operative outcomes in adult patients undergoing ACDF, PCF, PLF, or LD surgeries.

RESULTS

Total of 4,307 publications were assessed. Twenty-one articles met inclusion criteria.

PCF AND ACDF

Decreased preoperative Hb/Hct were significant predictors of increased postoperative morbidity, including return to operating room, pulmonary complications, transfusions, and increased length of stay (LOS). For increased HbA1c, there was significant increase in risk of postoperative infection and cost of hospital stay.

PLF

Decreased Hb/Hct was reported to be associated with increased risk of postoperative cardiac events, blood transfusion, and increased LOS. Elevated HbA1c was associated with increased risk of infection as well as higher visual analogue scores (VAS) and Oswestry disability index (ODI) scores.

LD

LOS and total episode of care cost were increased in patients with preoperative HbA1c elevation.

CONCLUSION

In adult patients undergoing spine surgery, preoperative Hb/Hct are clinically useful predictors for postoperative complications, transfusion rates, and LOS, and HbA1c is predictive for postoperative infection and functional outcomes. Using Hct values <35-38% and HbA1c >6.5%-6.9% for identifying patients at higher risk of postoperative complications is most supported by the literature. We recommend obtaining these labs as part of routine pre-operative risk stratification.

LEVEL OF EVIDENCE

III.

Short term outcomes associated with patients requiring blood transfusion following elective laminectomy and fusion for lumbar stenosis: A propensity-matched analysis

Perioperative blood transfusion has been associated with poor outcomes but the impacts of transfusion after fusion for lumbar stenosis have not been well-described. We assessed this effect in a large cohort of patients from 2012 to 2018 in the National Surgical Quality Improvement Program (NSQIP). We evaluated baseline characteristics including demographics, comorbidities, hematocrit, and operative characteristics. We generated propensity scores using baseline characteristics and patients were matched to approximate randomization. We assessed odds of 30-day outcomes including prolonged length-of-stay (LOS), complications, discharge to facility, readmission, reoperation, and death using logistic regression. We identified 16,329 eligible patients who underwent lumbar fusion for stenosis; 1,926 (11.8%) received a transfusion. Before matching, there were multiple differences in baseline covariates including age, gender, BMI, ASA class, medical comorbidities, hematocrit, coagulation indices, platelets, operative time, fusion technique, number of levels fused, and osteotomy. However, after matching, no significant differences remained. In the matched cohorts, transfusion was associated with increased prolonged LOS (OR 1.66, 95% CI 1.45-1.91, p < 0.001), minor complication (OR 1.60, 95% CI 1.20-2.12, p = 0.001), major complication (OR 1.51, 95% CI 1.16-1.98, p = 0.003), any complication (OR 1.54, 95% CI 1.24-1.92, p < 0.001), discharge to facility (OR 1.70, 95% CI 1.48-1.95, p < 0.001), 30-day readmission (OR 1.56, 95% CI 1.23-1.99, p < 0.001), and 30-day reoperation (OR 1.85, 95% CI 1.35-2.53, p < 0.001). Although transfusion is performed based on perceived clinical need, this study contributes to growing evidence that it is important to balance the risks of perioperative blood transfusion with its benefits.

Minimizing Blood Loss in Spine Surgery

STUDY DESIGN

Broad narrative review.

OBJECTIVE

To review and summarize the current literature on guidelines, outcomes, techniques and indications surrounding multiple modalities of minimizing blood loss in spine surgery.

METHODS

A thorough review of peer-reviewed literature was performed on the guidelines, outcomes, techniques, and indications for multiple modalities of minimizing blood loss in spine surgery.

RESULTS

There is a large body of literature that provides a consensus on guidelines regarding the appropriate timing of discontinuation of anticoagulation, aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), and herbal supplements prior to surgery. Additionally, there is a more heterogenous discussion the utility of preoperative autologous blood donation facilitated by erythropoietin and iron supplementation for healthy patients slated for procedures with high anticipated blood loss and for whom allogeneic transfusion is likely. Intraoperative maneuvers available to minimize blood loss include positioning and maintaining normothermia. Tranexamic acid (TXA), bipolar sealer electrocautery, and topical hemostatic agents, and hypotensive anesthesia (mean arterial pressure (MAP) <65 mm Hg) should be strongly considered in cases with larger exposures and higher anticipated blood loss. There is strong level 1 evidence for the use of TXA in spine surgery as it reduces the overall blood loss and transfusion requirements.

CONCLUSION

As the volume and complexity of spinal procedures rise, intraoperative blood loss management has become a pivotal topic of research within the field. There are many tools for minimizing blood loss in patients undergoing spine surgery. The current literature supports combining techniques to use a cost- effective multimodal approach to minimize blood loss in the perioperative period.

Incidence and cost of perioperative red blood cell transfusion for elective spine fusion in a high-volume center for spine surgery

Background

Spine fusion is a surgical procedure characterized by a significant perioperative bleeding, which often requires red blood cell (RBC) transfusion.

Methods

The incidence and the cost of RBC transfusion were evaluated in all patients undergoing elective surgery for spine fusion in our Institution, a high-volume center for spine surgery, over a period of 3 years. The analysis specifically addressed the RBC transfusion need in all the different spine fusion procedures (atlanto-axial, cervical, dorsal, lumbar, revisions) with the different surgical approaches (anterior, posterior).

Results

During the 3 years of observation, a total of 1.882 elective spine fusions were performed. More than half of the procedures (n = 964) were posterior lumbar fusions. Overall, 5% of the patients (n = 103) required RBC transfusion. The cervical fusions were the procedures with the lowest percentage of RBC need (0–5%), while the dorsal and the lumbar ones, with the anterior approach, represented the procedures with the highest rate of transfusion (29% and 25% respectively). More than 60 % of the RBC units were employed in the instance of posterior lumbar fusion, while a variable 1–10% of the units was used in each of the other procedures. The overall transfusion cost was of 46.000 euros, with a distribution of costs that paralleled the amount of units transfused for each procedure.

Conclusions

Several surgical and patient factors may contribute to the perioperative blood loss. An accurate patient blood management, may efficiently decrease transfusion requirements and ultimately healthcare costs.