Perioperative Risk Factors for Thirty-Day Morbidity and Mortality in the Resection of Extradural Thoracic Spine Tumors

The utilization of hypoalbuminemia as a prognostic metric in patients with spinal metastases: A scoping review

Introduction

Hypoalbuminemia is associated with poor outcomes in cancer patients, but its role in spinal metastases remains unclear.

Research question

This study aimed to identify albumin cutoff values defining hypoalbuminemia and describe the association between serum albumin and outcomes in patients with spinal metastases.

Material and methods

A narrative review of articles up to December 2022 was conducted using PubMed/Medline, EMBASE, and Web of Science databases. Variables extracted included study design, patient characteristics, serum albumin levels, treatments, and levels of evidence. Outcomes included survival/mortality, complications, ambulatory status, readmission, length of stay, discharge disposition, and blood loss.

Results

Thirty-eight studies comprising 21,401 patients were analyzed. Most studies (92%) were Level of Evidence III. Albumin was evaluated as a continuous variable in 18% of studies and as a dichotomous variable in 76%, with 3.5 g/dL being the most common threshold for hypoalbuminemia. Primary outcomes evaluated were survival/mortality (71% of studies), complications (34%), and reoperation/readmission (11%). Of studies examining the association between hypoalbuminemia and survival/mortality, 74% found a significant association. An association between albumin levels and complications was found in 54% of relevant studies.

Discussion and conclusion

The findings of this study suggest that a threshold of 3.5 g/dL seems most appropriate to define hypoalbuminemia in patients with spinal metastases. However, evidence also supports a level-dependent effect. The most consistent significant association was between low albumin and survival at both fixed and continuous time points. There is less evidence to support an association between hypoalbuminemia and other endpoints such as perioperative complications.

Malnutrition in Spine Oncology: Where Are We and What Are We Measuring?

STUDY DESIGN

Scoping review.

OBJECTIVE

To identify which markers are used as surrogates for malnutrition in metastatic spine disease and which are the most studied outcomes associated with it.

METHODS

A scoping review was performed by searching the PubMed/Medline, EMBASE, and Web of Science databases up to July 2022. We searched for articles exploring markers of malnutrition in spine oncology patients including but not limited to albumin, body weight, weight loss, and nutrition indices. A narrative synthesis was performed.

RESULTS

A total of 61 articles reporting on 31,385 patients met inclusion criteria. There were 13 different surrogate markers of nutrition, with the most common being albumin in 67% of studies (n = 41), body weight/BMI in 34% (n = 21), and muscle mass in 28% (n = 17). The most common studied outcomes were survival in 82% (n = 50), complications in 28% (n = 17), and length of stay in 10% (n = 6) of studies. Quality of life and functional outcomes were assessed in 2% (n = 1) and 3% (n = 2) of studies, respectively. Out of 61 studies, 18% (n = 11) found no association between the examined markers and outcome.

CONCLUSION

Assessment of nutritional status in patients with spinal metastases is fundamental. However, there is lack of a comprehensive and consistent way of assessing malnutrition in oncologic spine patients and therefore inconsistency in its relationship with outcomes. A consensus agreement on the assessment and definition of malnutrition in spine tumor patients is needed.

Association of preoperative hypoprotein malnutrition with spinal postoperative complications and other conditions: A systematic review and meta-analysis

BACKGROUND

Postoperative complications of spinal surgery are a common clinical problem, which impose significant economic and clinical burdens on patients and medical staff. Previous studies have suggested a close relationship between low-protein malnutrition and postoperative complications of surgery. However, the relationship between preoperative malnutrition and various orthopedic postoperative complications remains unclear.

PURPOSE

To investigate the association between protein malnutrition and postoperative complications and outcomes.

METHODS

We conducted a systematic search of the PubMed, Embase, Cochrane Library, and Web of Science databases for published research articles between the database inception and February 28th, 2023, that evaluated the association between malnutrition and the risk of postoperative complications and death in spinal surgery patients. Malnutrition was defined as low pre-albumin and albumin levels before surgery. Two evaluators independently extracted study data and assessed the risk of bias in each study. Fixed- or random-effect models were used to calculate the pooled effect estimates. Funnel plots and Egger's tests were used to detect publication bias, and the Trim-and -Fill method was conducted to evaluate the impact of publication bias on the results.

RESULTS

A total of 26 studies were included in this meta-analysis, comprising 17 retrospective cohort studies and 9 case-control studies. The study included more than 86,000 participants. Analysis of postoperative complications revealed that the overall incidence of malnutrition-related complications after surgery was 3.17 times higher (OR = 3.17, 95% CI 2.69-3.75, z = 13.57, P < 0.05). The incidence of surgical site infections was 2.08 times higher (OR = 2.08, 95% CI 1.66-2.62, z = 6.307, P < 0.05), and the incidence of postoperative urinary tract infections was 2.55 times higher (OR = 2.55, 95% CI 1.80-3.60, z = 5.30, P < 0.05). The incidence of postoperative sepsis was 3.31 times higher (OR = 3.31, 95% CI 2.31-4.75, z = 6.51, P < 0.05), and the incidence of postoperative pneumonia was 3.02 times higher (OR = 3.02, 95% CI 1.331-6.857, z = 2.64, P = 0.008 < 0.05). The incidence of postoperative cardiac complications was 4.24 times higher (OR = 4.24, 95% CI 2.45-7.35, z = 5.15, P < 0.05), and the incidence of postoperative renal complications was 4.04 times higher (OR = 4.04, 95% CI 2.06-7.93, z = 4.05, P < 0.05). The incidence of postoperative pulmonary complications was 2.38 times higher (OR = 2.38, 95% CI 1.46-3.87, z = 6.98, P < 0.05), while the incidence of postoperative thrombotic complications was 2.76 times higher (OR = 2.76, 95% CI 1.756-4.345, z = 4.40, P < 0.05). Furthermore, the incidence of transfusion during and after surgery was 1.33 times higher (OR = 1.33, 95% CI 1.13-1.56, z = 3.40, P = 0.001 < 0.05), the incidence of postoperative readmission was 1.67 times higher (OR = 1.67, 95% CI 1.24-2.27, z = 3.33, P = 0.001 < 0.05), and the risk of postoperative death was 6.01 times higher (OR = 6.01, 95% CI 4.51-8.01, z = 12.27, P < 0.05). After conducting a publication bias test and Trim-and -Fill method analysis, we found no evidence of publication bias, and the results remained stable.

CONCLUSION

Preoperative low protein malnutrition is closely related to the incidence of postoperative complications and postoperative status. More prospective multicenter studies should be conducted to validate this conclusion. Furthermore, more effective assessment and intervention of preoperative nutritional status should be carried out to prevent the occurrence of postoperative complications and mortality risk.

Predicting 30-day mortality after surgery for metastatic disease of the spine: the H2-FAILS score

PURPOSE

Scoring systems for metastatic spine disease focus on predicting long- to medium-term mortality or a combination of perioperative morbidity and mortality. However, accurate prediction of perioperative mortality alone may be the most important factor when considering surgical intervention. We aimed to develop and evaluate a new tool, the H2-FAILS score, to predict 30-day mortality after surgery for metastatic spine disease.

METHODS

Using the National Surgical Quality Improvement Program database, we identified 1195 adults who underwent surgery for metastatic spine disease from 2010 to 2018. Incidence of 30-day mortality was 8.7% (n = 104). Independent predictors of 30-day mortality were used to derive the H2-FAILS score. H2-FAILS is an acronym for: Heart failure (2 points), Functional dependence, Albumin deficiency, International normalized ratio elevation, Leukocytosis, and Smoking (1 point each). Discrimination was assessed using area under the receiver operating characteristic curve (AUC). The H2-FAILS score was compared with the American Society of Anesthesiologists Physical Status Classification (ASA Class), the 5-item modified Frailty Index (mFI-5), and the New England Spinal Metastasis Score (NESMS). Internal validation was performed using bootstrapping. Alpha = 0.05.

RESULTS

Predicted 30-day mortality was 1.8% for an H2-FAILS score of 0 and 78% for a score of 6. AUC of the H2-FAILS was 0.77 (95% confidence interval: 0.72-0.81), which was higher than the mFI-5 (AUC 0.58, p < 0.001), ASA Class (AUC 0.63, p < 0.001), and NESMS (AUC 0.70, p = 0.004). Internal validation showed an optimism-corrected AUC of 0.76.

CONCLUSIONS

The H2-FAILS score accurately predicts 30-day mortality after surgery for spinal metastasis.

LEVEL OF EVIDENCE

Prognostic level III.

Racial Disparities in Perioperative Morbidity Following Oncological Spine Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To assess the impact of race on complications following spinal tumor surgery.

METHODS

Adults with cancer who underwent spine tumor surgery were identified in the American College of Surgeons National Surgical Quality Improvement Program datasets from 2012 to 2016. Clavien-Dindo Grade I-II (minor complications) and Clavien-Dindo Grade III-V (major complications including 30-day mortality) complications were compared between non-Hispanic Whites (NHW) and Black patients. A multivariable analysis was also conducted.

RESULTS

Of 1,226 identified patients, 85.9% were NHW (n = 1,053) and 14.1% were Black (n = 173). The overall rate of Grade I-II complications was 16.2%; 15.1% for NHW patients and 23.1% for Black patients (P = .008). On multivariable analysis, Black patients had significantly higher odds of having a minor complication (OR 1.87; 95% CI, 1.16-3.01; P = .010). On the other hand, the overall rate of Grade III-V complications was 13.3%; 12.5% for NHW patients and 16.2% for Black patients (P = .187). On multivariable analysis, Black race was not independently associated with major complications (OR 1.26; 95% CI, 0.71-2.23; P = .430). Median length of stay was 8 days (IQR 5-13) for NHW patients and 10 days (IQR 6-15) for Black patients (P = .011).

CONCLUSION

Black patients who underwent metastatic spinal tumor surgery were at a significantly increased risk of perioperative morbidity compared to NHW patients independent of baseline and operative characteristics. Major complications did not differ between groups. Race should be further studied in the context of metastatic spine disease to improve our understanding of these disparities.

Increased Severity of Anemia Is Associated with Postoperative Complications following a Adult Spinal Deformity Surgery

BACKGROUND

Anemia is a modifiable risk factor for postoperative complications following surgery. This study aimed to determine the impact of preoperative anemia severity on 30-day postoperative complications following adult spinal deformity (ASD) surgery.

METHODS

Adults undergoing spinal fusion for ASD from 2012 to 2018 were identified in the National Surgical Quality Improvement Program database. Patients were substratified into 3 cohorts-non-anemia, mild anemia, and moderate-to-severe anemia-based on World Health Organization definitions. We assessed 30-day wound, cardiac, pulmonary, renal, and thromboembolic complications, as well as sepsis, mortality, postoperative transfusions, extended length of stay, and reoperation. Bivariate analyses and multivariable logistic regression were performed.

RESULTS

Of 2173 patients, 1694 (78%) had no anemia, 307 (14%) had mild anemia, and 172 (8%) had moderate or severe anemia. Following adjustments, patients with mild anemia were more likely to have postoperative blood transfusions (odds ratio [OR] 1.80, P < 0.001) and extended length of stay (OR 1.43, P < 0.001). Patients with moderate-to-severe anemia were at increased risk of organ space infection (OR 3.27, P = 0.028), death (OR 13.15, P = 0.001), postoperative blood transfusion (OR 2.81, P < 0.001), and extended length of stay (OR 3.02, P < 0.001).

CONCLUSIONS

We found a stepwise and approximately two-fold increase in the odds ratio of postoperative transfusion and length of stay with increasing severity of anemia. Moderate-to-severe anemia was associated with increased odds of death and organ space infection. Patients with moderate-to-severe anemia should be medically optimized before ASD surgery.

Effectiveness of Preoperative Embolization in Patients with Spinal Metastases: A Systematic Review and Meta-Analysis

OBJECTIVE

Debate on the effectiveness of preoperative embolization for spinal metastatic lesions, especially for nonhypervascular tumors, has persisted. The present study aimed to identify the effectiveness of preoperative embolization in patients who had undergone surgery for spinal metastasis.

METHODS

Two of us (Z.T. and Z.H.) independently searched the PubMed, Embase, and Cochrane Central Register of Controlled Trials databases to identify eligible clinical studies that had compared the outcomes of patients treated surgically for spinal metastatic disease with or without preoperative embolization. The primary outcomes included intraoperative blood loss, perioperative blood loss, and transfusion requirements. The secondary outcomes include the operative time, overall survival, and complication rates. Meta-analyses were performed for subgroups of hypervascular, nonhypervascular, and mixed tumors. A fixed effects model was applied when I² was <50%, and a random effects model was applied when I² was >50%.

RESULTS

A total of 12 studies (1 randomized controlled trial and 11 retrospective case-control studies), with 744 patients, were included. Significantly less intraoperative blood loss (mean difference [MD], -1171.49 mL; 95% confidence interval [CI], -2283.10 to -59.88; P = 0.039), fewer blood transfusions (MD, -3.13 U; 95% CI, -4.86 to -1.39; P < 0.001), and shorter operative times (MD, -33.91 minutes; 95% CI, -59.65 to -8.17; P = 0.010) were identified for the embolization group in the hypervascular subgroup. In the nonhypervascular and mixed tumor subgroups, no differences in effectiveness were identified in blood loss, transfusion requirement, or operative time when stratified by the use of embolization. The overall survival and complication rates were similar between the embolization and nonembolization groups in each subgroup.

CONCLUSIONS

The current data support the use of preoperative embolization for hypervascular metastatic tumors to the spine. However, little evidence is available to support the use of preoperative embolization for nonhypervascular metastatic tumors to the spine.

A Novel Clinical Scoring System for Perioperative Morbidity in Metastatic Spinal Tumor Surgery: The Spine Oncology Morbidity Assessment Score

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To evaluate a scoring system to predict morbidity for patients undergoing metastatic spinal tumor surgery (MSTS).

SUMMARY OF BACKGROUND DATA

Multiple scoring systems exist to predict survival for patients with spinal metastasis. The potential benefits and risks of surgery need to be evaluated for patients with disseminated cancer and limited life expectancy. Few scoring systems exist to predict perioperative morbidity after MSTS.

METHODS

We reviewed records of patients who underwent MSTS at our institution between 2013 and 2019. All perioperative complications occurring within 30 days were recorded. A clinical scoring system consisting of five variables (age ≥ 70 yr, hypoalbuminemia, poor preoperative functional status [Karnofsky ≤ 40], Frankel Grade A-C, and multilevel disease ≥2 continuous vertebral bodies) was evaluated as a predictive tool for morbidity; every parameter was assigned a value of 0 if absent or 1 if present (total possible score = 5). The effect of the scoring system on morbidity was evaluated using stepwise multiple logistic regression. Model accuracy was calculated by receiver operating characteristic analysis.

RESULTS

One hundred and five patients were identified, with a male prevalence of 58.1% and average age at surgery of 61 years. The overall 30-day complication rate was 36.2%. The perioperative morbidity was 4.6%, 30.0%, 53.9%, and 64.7% for patients with scores of 0, 1, 2, and ≥3 points, respectively (P < 0.001). On multiple logistic regression analysis controlling for covariates not present in the model, the scoring system was significantly associated with 30-day morbidity (OR 3.11; 95% CI, 1.72-5.59; P < 0.001). The model's accuracy was estimated at 0.75.

CONCLUSION

Our proposed model was found to accurately predict perioperative morbidity after MSTS. The Spine Oncology Morbidity Assessment (SOMA) score may prove useful for risk stratification and possibly decision-making, though further validation is needed.Level of Evidence: 4.

Risk Factors for 30-Day Non-Neurological Morbidity and Cerebrospinal Fluid Leak in Patients Undergoing Surgery for Vestibular Schwannoma

Introduction  We analyzed perioperative risk factors for morbidity and mortality for the patients undergoing surgical intervention for vestibular schwannoma along with rates of cerebrospinal fluid (CSF) leaks that required surgery. Materials and Methods  Patients undergoing surgery vestibular schwannoma were identified in the American College of Surgeons National Surgical Quality Improvement Program database from 2012 to 2016 using current procedural terminology (CPT) codes for posterior fossa surgical approaches and International Classification of Diseases 9th revision (ICD 9) and ICD 10 codes for peripheral nerve sheath tumor. Preoperative laboratories, comorbidities, and operative times were analyzed along with CSF leaks and unplanned returns to the operating room. Results  Nine-hundred ninety-three patients fit the inclusion criteria. Average age was 51, 41% were male, and 58% were female. Mortality within 30 days of the operation was very low at 0.4%, complications were 7% with infection being the most common at 2.3%, and unplanned reoperations happened in 7.4% of the cases. Dependent functional status (odds ratio [OR]: 5.7, 95% confidence interval [CI]: 1.9-16.6, p  = 0.001), preoperative anemia (OR: 2.4, 95% CI: 1.2-4.5, p  = 0.009), and operative time over 8 hours (OR: 1.9, 95% CI: 1.1-3.4, p  = 0.017) were the only significant predictors of perioperative complications. CSF leak postoperatively occurred in 37 patients (3.7%). Reoperation for CSF leak was necessary in 56.3% of the cases. Operative time over 8 hours was the only independent significant predictor of postoperative CSF leak (OR: 2.2, 95% CI: 1.1-4.3, p  = 0.028). Conclusion  Dependent functional status preoperatively, preoperative anemia, and duration of surgery over 8 hours are the greatest predictors of complications in the 30-day postoperative period.

A National Surgical Quality Improvement Program Analysis of Postoperative Major and Minor Complications in Patients with Spinal Metastatic Disease

BACKGROUND

Major complications after spine metastasis surgery are prioritized in the literature with little consideration of the more frequent minor events such as pneumonia or urinary tract infection. We analyzed incidence and risk factors of postsurgical complications in patients with spinal metastasis extracted from the National Surgical Quality Improvement Program (NSQIP). We also developed a useful predictive model to estimate the probability of occurrence of complications.

METHODS

A total of 1176 patients diagnosed with spinal metastasis were extracted from NSQIP. Variables screened included age, sex, tumor location, patient's functional status, comorbidities, laboratory values, and case urgency. Two multivariate logistic regression models were designed to evaluate risk factors and likelihood of event occurrence.

RESULTS

Minor events occurred twice as frequently compared with major complications (36% vs. 18% of patients). The most common major event was death (10%); the most frequent minor event was need for postoperative transfusion (29.4%). In the multivariate analysis, elderly age, emergency case, preoperative leukocytosis, and smoking status retained significance for major complications; American Society of Anesthesiologists classes 4-5, low hematocrit levels, and intradural extramedullary location of the tumor retained significance for minor complications. The predictive models designed explained 72% of the variability in major complications occurrence and 67% for minor events.

CONCLUSIONS

Smoking status and emergent surgery were found to be the strongest independent predictors of major complications, whereas higher American Society of Anesthesiologists class showed a greater association with minor events. The predictive models produced can be a useful aid for surgeons to identify those patients who are at greater risk of developing postoperative adverse events.

Anemia and perioperative mortality in non-cardiac surgery patients: a secondary analysis based on a single-center retrospective study

Background

Evidence regarding the relationship between anemia and perioperative prognosis is controversial. The study was conducted to highlight the specific relationship between anemia and perioperative mortality in non-cardiac surgery patients over 18 years of age.

Methods

This study was a retrospective analysis of the electronic medical records of 90,784 patients at the Singapore General Hospital from January 1, 2012 to October 31, 2016. Multivariate regression, propensity score analysis, doubly robust estimation, and an inverse probability-weighting model was used to ensure the robustness of our findings.

Results

We identified 85,989 patients, of whom75, 163 had none or mild anemia (Hemoglobin>90g/L) and 10,826 had moderate or severe anemia (Hemoglobin≤90g/L). 8,857 patients in each study exposure group had similar propensity scores and were included in the analyses. In the doubly robust model, postoperative 30-day mortality rate was increased by 0.51% (n = 219) in moderate or severe anemia group (Odds Ratio, 1.510; 95% Confidence Interval (CI), 1.049 to 2.174) compared with none or mild anemia group (2.47% vs.1.22%, P<0.001). Moderate or severe anemia was also associated with increased postoperative blood transfusion rates (OR, 5.608; 95% CI, 4.026 to 7.811, P < 0.001). There was no statistical difference in Intensive Care Unit (ICU) admission rate among different anemia groups within 30 days after surgery (P=0.104).

Discussion

In patients undergoing non-cardiac surgery over 18 years old, moderate or severe preoperative anemia would increase the occurrence of postoperative blood transfusion and the risk of death, rather than ICU admission within 30 days after surgery.

Rates, Risk Factors, and Complications of Red Blood Cell Transfusion in Metastatic Spinal Tumor Surgery: An Analysis of a Prospective Multicenter Surgical Database

OBJECTIVE

To identify rates, risks, and complications of red blood cell (RBC) transfusion in metastatic spinal tumor surgery.

METHODS

The multicenter prospective American College of Surgeons National Quality Improvement Program database was queried for the years 2012-2016. Adult patients with disseminated cancer who underwent metastatic spinal tumor surgery were identified. Transfusion was defined as having received at least 1 intraoperative/postoperative RBC transfusion within the first 72 hours of surgery start time. A stepwise multiple logistic regression model with backward elimination was used.

RESULTS

Of 1601 patients identified, 623 patients (38.9%) received a RBC transfusion. Independent predictors of RBC transfusion included higher American Society of Anesthesiologists class (odds ratio [OR] = 1.54), preoperative anemia (OR = 3.10), instrumentation (OR = 1.63), and longer operative time (OR = 1.52). The overall complication rate was significantly higher in patients who received a transfusion compared with patients who did not receive a transfusion (22.3% vs. 15.0%, P < 0.001). Individual complications that were more common in patients who received a transfusion were sepsis (3.5% vs. 1.9%, P = 0.050), deep vein thrombosis (6.1% vs. 3.3%, P = 0.007), and prolonged ventilation (3.9% vs. 1.3%, P = 0.001). RBC transfusion (OR = 1.65), hypoalbuminemia (OR = 1.53), and anterior/anterolateral approaches for corpectomy (OR = 2.11) were independent risk factors for developing a postoperative complication.

CONCLUSIONS

RBC transfusion after metastatic spinal tumor surgery may increase the risk of early postoperative complications. Future research into preoperative patient optimization and decreasing intraoperative blood loss is needed.