Are allogeneic blood transfusions associated with decreased survival after surgical treatment for spinal metastases?

Surgical Outcomes After Preoperative Embolization in Hypervascular Spinal Metastases: A Propensity Scored Study of 191 Patients

STUDY DESIGN

Retrospective propensity-score matched, case-control study at 2 academic tertiary care centers.

OBJECTIVE

To assess the effect of preoperative embolization (PE) on (1) intraoperative blood loss, defined as conventional estimates of blood loss (EBL) and hemoglobin mass loss; and (2) secondary outcomes in patients with spinal metastases from hypervascular histologies.

BACKGROUND CONTEXT

PE intends to reduce blood loss during surgery for spinal metastases of hypervascular tumors such as renal cell carcinoma. However, studies investigating the effect of PE in hypervascular tumors often consist of small cohorts, do not correct for confounding factors, and have conflicting results.

MATERIALS AND METHODS

After propensity score matching, 46 PE patients were matched to 46 non-PE patients without baseline differences. The constraints of propensity score matching did not allow analysis of patients with tumor volumes >9 cm 3 . Multiple linear regression models were fitted for EBL and hemoglobin mass loss. Poisson regression models were fitted for both intraoperative and postoperative transfusions.

RESULTS

There was no difference in EBL [948 mL (IQR: 500-1750) vs. 1100 mL (IQR: 388-1925), P =0.68] and hemoglobin mass loss [201 g (IQR: 119-307) vs. 232 g (IQR: 173-373), P =0.18] between PE and non-PE patients. Other than higher 1-year survival rates (65% vs. 43%, P =0.05) in PE patients, there were no differences in secondary outcomes. In multiple regression analyses, PE was not associated with decreased intraoperative blood loss, hemoglobin mass loss, or perioperative blood transfusions.

CONCLUSIONS

Our study demonstrated that, for tumors <9 cm 3 , PE did not reduce EBL, hemoglobin mass loss, or perioperative blood transfusions in patients undergoing spine surgery for metastases from hypervascular histologies. These findings suggest that urgent spine surgeries indicated for hypervascular histologies should not be delayed based on the availability of PE and accurate detection of preoperative hypervascularity, beyond histology, will likely be an important determination of future PE utilization for spinal metastases.

LEVEL OF EVIDENCE

Level III-treatment benefits.

Does Patient Blood Management Affect Outcomes in Metastatic Spine Tumour Surgery? A Review of Current Concepts

STUDY DESIGN

Narrative review.

OBJECTIVE

The spine is the most common site of metastases, associated with decreased quality of life. Increase in metastatic spine tumour surgery (MSTS) has caused us to focus on the management of blood, as blood loss is a significant morbidity in these patients. However, blood transfusion is also not without its own risks, and hence this led to blood conservation strategies and implementation of a concept of patient blood management (PBM) in clinical practise focusing on these patients.

METHODS

A narrative review was conducted and all studies that were related to blood management in metastatic spine disease as well as PBM surrounding this condition were included.

RESULTS

A total of 64 studies were included in this review. We discussed a new concept of patient blood management in patients undergoing MSTS, with stratification to pre-operative and intra-operative factors, as well as anaesthesia and surgical considerations. The studies show that PBM and reduction in blood transfusion allows for reduced readmission rates, lower risks associated with blood transfusion, and lower morbidity for patients undergoing MSTS.

CONCLUSION

Through this review, we highlight various pre-operative and intra-operative methods in the surgical and anaesthesia domains that can help with PBM. It is an important concept with the significant amount of blood loss expected from MSTS.

LEVEL OF EVIDENCE

Not applicable.

Impact of Obesity on Perioperative Complications on Treatment of Spinal Metastases: A Multicenter Surveillance Study from the German Spine Registry (DWG-Register)

Background  The spine is a common location for the development of primary and metastatic tumors, spinal metastases being the most common tumor in the spine. Spinal surgery in obesity is challenging due to difficulties with anesthesia, intravenous access, positioning, and physical access during surgery. The objective was to investigate the effect of obesity on perioperative complications by discharge in patients undergoing surgery for spinal metastases.

Methods  Retrospective analysis of data from the DWG-register on patients undergoing surgery for metastatic disease in the spine from January 2012 to December 2016. Preoperative variables included obesity (≥ 30 kg/m ² ), age, gender, and smoking status. In addition, the influence of pre-existing medical comorbidity was determined, using the American Society of Anesthesiologists (ASA) score.

Results  In total, 528 decompressions with and without instrumentation undergoing tumor debulking, release of the neural structures, or tumor extirpation in metastatic disease of the spine were identified; 143 patients were obese (body mass index [BMI] ≥ 30 kg/m ² ), and 385 patients had a BMI less than 30 kg/m ² . The mean age in the group with BMI 30 kg/m ² or higher (group 1) was 67 years (56.6%). In the group with BMI less than 30 kg/m ² (group 2), the mean age was 64 years. Most of the patients had preoperatively an ASA score of 3 and 4 (patients with severe general disease). The likelihood of being obese in the logistic regression model seems to be protective by 47.5-fold for blood loss 500 mL or higher. Transfusions occurred in 321/528 (60.7%) patients (group 1, n  = 122 and group 2, n  = 299; p  = 0.04). A total of 19 vertebroplasties with percutaneous stabilization (minimally invasive spine [MIS]), 6 vertebroplasties, and 31 MIS alone were identified. The variables between these groups, with exception of preoperative status (ASA-score; p  = 0.02), remained nonsignificant.

Conclusion  Obese patients were predisposed to have blood loss more than 500 mL more often than nonobese patients undergoing surgery for spinal metastases but with perioperative blood transfusions, invasiveness, nor prolonged hospitalization. Early postoperative mobilization and a low threshold for perioperative venous thromboembolism (VTE) are important in obese patients to appropriately diagnose, treat complications, and minimize morbidity.

Preoperative embolization in surgical treatment of spinal metastases originating from non-hypervascular primary tumors: a propensity score matched study using 495 patients

BACKGROUND CONTEXT

Preoperative embolization (PE) reduces intraoperative blood loss during surgery for spinal metastases of hypervascular primary tumors such as thyroid and renal cell tumors. However, most spinal metastases originate from primary breast, prostate, and lung tumors and it remains unclear whether these and other spinal metastases benefit from PE.

PURPOSE

To assess the (1) efficacy of PE on the amount of intraoperative blood loss and safety in patients with spinal metastases originating from non-hypervascular primary tumors, and (2) secondary outcomes including perioperative allogeneic blood transfusion, anesthesia time, hospitalization, postoperative complication within 30 days, reoperation, 90-day mortality, and 1-year mortality.

STUDY DESIGN

Retrospective propensity-score matched, case-control study at 2 academic tertiary medical centers.

PATIENT SAMPLE

Patients 18 years of age or older undergoing surgery for spinal metastases originating from primary non-thyroid, non-renal cell, and non-hepatocellular tumors between January 1, 2002 and December 31, 2016 were included.

OUTCOME MEASURES

The primary outcomes were estimated amount of intraoperative blood loss and complications attributable to PE, such as neurologic injury, wound infection, thrombosis, or dissection. The secondary outcomes included perioperative allogeneic blood transfusion, anesthesia time, hospitalization, postoperative complication within 30 days, reoperation, 90-day mortality, and 1-year mortality.

METHODS

In total, 495 patients were identified, of which 54 (11%) underwent PE. After propensity score matching on 21 variables, including primary tumor, number of spinal levels, and surgical treatment, 53 non-PE patients were matched to 53 PE patients. Matching was adequate measured by comparing the matched variables, testing the standardized mean differences (<0.25), and inspecting Kernel density plots. The degree of embolization was noted to be complete, until stasis, or successful in 43 (80%) patients.

RESULTS

Intraoperative blood loss did not differ between both groups with a median blood loss in liters of 0.6 (IQR, 0.4-1.2) for non-PE patients and 0.9 (IQR, 0.6-1.2) for PE patients (p=.32). No complications occurred during embolization or the time between embolization and surgery. No differences were found in terms of the secondary outcomes.

CONCLUSIONS

Our data suggest that, although no complications occurred and the embolization procedure can be considered safe, patients with non-hypervascular spinal metastases might not benefit from PE. A larger, prospective study could confirm or refute these study findings and aid in elucidating a subset of spinal metastases that might benefit from PE.

Body composition predictors of mortality on computed tomography in patients with spinal metastases undergoing surgical treatment

BACKGROUND CONTEXT

Although survival of patients with spinal metastases has improved over the last decades due to advances in multi-modal therapy, there are currently no reliable predictors of mortality. Body composition measurements obtained using computed tomography (CT) have been recently proposed as biomarkers for survival in patients with and without cancer. Patients with cancer routinely undergo CT for staging or surveillance of therapy. Body composition assessed using opportunistic CTs might be used to determine survival in patients with spinal metastases.

PURPOSE

The purpose of this study was to determine the value of body composition measures obtained on opportunistic abdomen CTs to predict 90-day and 1-year mortality in patients with spinal metastases undergoing surgery. We hypothesized that low muscle and abdominal fat mass were positive predictors of mortality.

STUDY DESIGN

Retrospective study at a single tertiary care center in the United States.

PATIENT SAMPLE

This retrospective study included 196 patients between 2001 and 2016 that were 18 years of age or older, underwent surgical treatment for spinal metastases, and had a preoperative CT of the abdomen within three months prior to surgery.

OUTCOME MEASURES

Ninety-day and 1-year mortality by any cause.

METHODS

Quantification of cross-sectional areas (CSA) and CT attenuation of abdominal subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), and paraspinous and abdominal skeletal muscle were performed on CT images at the level of L4 using an in-house automated algorithm. Sarcopenia was determined by total muscle CSA (cm²) divided by height squared (m²) with cutoff values of <52.4 cm²/m² for men and <38.5 cm²/m² for women. Bivariate and multivariate Cox proportional-hazard analyses were used to determine the associations between body compositions and 90-day and 1-year mortality.

RESULTS

The median age was 62 years (interquartile range=53-70). The mortality rate for 90-day was 24% and 1-year 54%. The presence of sarcopenia was associated with an increased 1-year mortality rate of 66% compared with a 1-year mortality rate of 41% in patients without sarcopenia (hazard ratio, 1.68; 95% confidence interval, 1.08-2.61; p=.02) after adjusting for various clinical factors including primary tumor type, ECOG performance status, additional metastases, neurology status, and systemic therapy. Additional analysis showed an association between sarcopenia and increased 1-year mortality when controlling for the prognostic modified Bauer score (HR, 1.58; 95%CI, 1.04-2.40; p=.03). Abdominal fat CSAs or muscle attenuation were not independently associated with mortality.

CONCLUSIONS

The presence of sarcopenia is associated with an increased risk of 1-year mortality for patients surgically treated for spinal metastases. Sarcopenia retained an independent association with mortality when controlling for the prognostic modified Bauer score. This implies that body composition measurements such as sarcopenia could serve as novel biomarkers for prediction of mortality and may supplement other existing prognostic tools to improve shared decision making for patients with spinal metastases that are contemplating surgical treatment.

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.

Updated external validation of the SORG machine learning algorithms for prediction of ninety-day and one-year mortality after surgery for spinal metastasis

BACKGROUND CONTEXT

Surgical decompression and stabilization in the setting of spinal metastasis is performed to relieve pain and preserve functional status. These potential benefits must be weighed against the risks of perioperative morbidity and mortality. Accurate prediction of a patient's postoperative survival is a crucial component of patient counseling.

PURPOSE

To externally validate the SORG machine learning algorithms for prediction of 90-day and 1-year mortality after surgery for spinal metastasis.

STUDY DESIGN/SETTING

Retrospective, cohort study PATIENT SAMPLE: Patients 18 years or older at a tertiary care medical center treated surgically for spinal metastasis OUTCOME MEASURES: Mortality within 90 days of surgery, mortality within 1 year of surgery METHODS: This is a retrospective cohort study of 298 adult patients at a tertiary care medical center treated surgically for spinal metastasis between 2004 and 2020. Baseline characteristics of the validation cohort were compared to the derivation cohort for the SORG algorithms. The following metrics were used to assess the performance of the algorithms: discrimination, calibration, overall model performance, and decision curve analysis.

RESULTS

Sixty-one patients died within 90 days of surgery and 133 died within 1 year of surgery. The validation cohort differed significantly from the derivation cohort. The SORG algorithms for 90-day mortality and 1-year mortality performed excellently with respect to discrimination; the algorithm for 1-year mortality was well-calibrated. At both postoperative time points, the SORG algorithms showed greater net benefit than the default strategies of changing management for no patients or for all patients.

CONCLUSIONS

With an independent, contemporary, and geographically distinct population, we report successful external validation of SORG algorithms for preoperative risk prediction of 90-day and 1-year mortality after surgery for spinal metastasis. By providing accurate prediction of intermediate and long-term mortality risk, these externally validated algorithms may inform shared decision-making with patients in determining management of spinal metastatic disease.

Adverse Effects of Perioperative Blood Transfusion in Spine Surgery

BACKGROUND

Perioperative blood transfusion is often necessary during spine surgery because of blood loss from the surgical field during and after surgery. However, blood transfusions are associated with a small but significant risk of causing several adverse events including hemolytic transfusion reactions and transfusion-associated circulatory overload. Moreover, many prior publications have noted increased rates of perioperative morbidity and worsened outcomes in spine surgery patients who received blood transfusions. We performed a systematic review of the literature to better characterize the effects of blood transfusion on spine surgery outcomes.

METHODS

The PubMed/MEDLINE database was queried using the composite key word "transfus∗ AND 'spine surgery.'" A title and abstract review were performed to identify articles for final inclusion.

RESULTS

A title and abstract review of the resulting 372 English-language articles yielded 13 relevant publications, which were subsequently incorporated into this systematic review. All included studies were retrospective, nonrandomized analyses.

CONCLUSIONS

Overall, prior literature indicates a relationship between perioperative blood transfusion and worsened outcomes after spine surgery. However, the available data represent level IV evidence at best. In the future, prospective, randomized, controlled studies may help define the effects of perioperative blood transfusion on spine surgery outcomes.

Delayed presentation to a spine surgeon is the strongest predictor of poor postoperative outcome in patients surgically treated for symptomatic spinal metastases

BACKGROUND CONTEXT

Symptoms associated with spinal metastases are often nonspecific and resemble noncancer-related symptoms. Therefore, patients with spinal metastases are at risk for delayed referral and treatment. Delayed presentation of symptomatic spinal metastases may lead to the development of neurological deficits, often followed by emergency surgery.

PURPOSE

The aim of this cohort study was to analyze the effect of delayed referral and treatment of spinal metastases on clinical outcome.

METHODS

We included all patients surgically treated for spinal metastases at our tertiary care center. Based on the (in)ability to undergo elective surgery, patients were identified as timely treated or delayed. Patient- and tumor-characteristics, surgical variables, and postoperative variables such as complication rate, the ability to return home and length of hospital stay were recorded and compared between the two groups.

RESULTS

Based on the urgency of treatment at admission, 206 patients were identified as timely treated and 98 as delayed. At baseline, the two groups did not differ significantly except for the extent of neurological symptoms. Timely treated patients underwent less invasive procedures (52.9% vs 13.3% percutaneous pedicle screw fixations), had less median blood loss (200cc vs 450cc), shorter median admission time (7 vs 13 days), lower complication rate (26.2% vs 48.0%) and higher chances of being discharged home immediately (82.6% vs 41.1%) compared with delayed patients. Using multivariate regression models these correlations remained present independent of tumor prognosis, preoperative mobility, and American Society of Anesthesiologists-score.

CONCLUSIONS

The delayed presentation of patients with spinal metastases to a spinal surgeon is strongly and independently associated with worse surgical and postoperative outcome parameters. Improvements in referral patterns could potentially lead to more scheduled care, negating the detrimental effects of delay.

Clinical Outcomes Associated With Allogeneic Red Blood Cell Transfusions in Spinal Surgery: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVES

The objectives of this systematic review were to report the available clinical evidence on patient outcomes associated with perioperative allogeneic red blood cell (RBC) transfusions in adult patients undergoing spinal surgery and to determine whether there is any evidence to support an association between transfusion timing and clinical outcomes.

METHODS

A systematic review of the PubMed, EMBASE, and Cochrane Library databases was performed to identify all articles examining outcomes of adult spinal surgery patients who received perioperative allogeneic RBC transfusions. The level of evidence for each study was assessed using the "Oxford Levels of Evidence 2" classification system. Meta-analysis was not performed due to the heterogeneity of reports.

RESULTS

A total of 2759 unique citations were identified and 76 studies underwent full-text review. Thirty-four studies were selected for analysis. All the studies, except one, were retrospective. Eleven studies investigated intraoperative or postoperative transfusions. Only one article compared outcomes related to intraoperative versus postoperative transfusions.

CONCLUSIONS

Perioperative transfusion is associated with increased rates of postoperative complications, especially infectious complications, and prolonged length of stay. Some evidence suggests that a dose-response relationship may exist between morbid events and the number of RBC units administered, but these findings are inconsistent. Because of the heterogeneity of reports and inconsistent findings, the incidence of specific complications remains unclear. Limited research activity has focused on intraoperative versus postoperative transfusions, or the effect of transfusion on functional outcomes of spine surgery patients. Further research is warranted to address these clinical issues.

Impact of Obesity on Surgical Outcomes Following Laminectomy for Spinal Metastases

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To determine the effect of obesity (body mass index >30 kg/m²) on perioperative morbidity and mortality after surgical decompression of spinal metastases.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database is a large multicenter clinical registry that collects preoperative risk factors, intraoperative variables, and 30-day postoperative morbidity and mortality outcomes from hospitals nationwide. Current Procedural Terminology codes were used to query the database for adults who underwent decompression with laminectomy for treatment of metastatic spinal lesions between 2010 and 2014. Patients were separated into 2 cohorts based on the presence of absence of obesity. Univariate analysis and multivariate logistic regression analysis were used to analyze the effect of obesity on perioperative morbidity and mortality.

RESULTS

There was a significantly higher rate of venous thromboembolism (VTE; obese 6.6% vs nonobese 4.2%; P = .01) and pulmonary complications (obese 2.6% vs nonobese 2.2%; P = .046) in the obese group compared with the nonobese group. The nonobese group had prolonged hospitalization (obese 62.0% vs nonobese 69.0%; P = .001) and a higher incidence of blood transfusions (obese 26.8% vs nonobese 34.2%; P < .001). On multivariate analysis, obesity was found to be an independent risk factor for VTE (odds ratio = 1.75, confidence interval = 1.17-2.63, P = .007).

CONCLUSIONS

Obese patients were predisposed to an elevated risk of VTE following laminectomy for spinal metastases. Early postoperative mobilization and a low threshold to evaluate for perioperative VTE are important in these patients in order to appropriately diagnose and treat these complications and minimize morbidity.

High-Risk Subgroup Membership Is a Predictor of 30-Day Morbidity Following Anterior Lumbar Fusion

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine if membership in a high-risk subgroup is predictive of morbidity and mortality following anterior lumbar fusion (ALF).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was utilized to identify patients undergoing ALF between 2010 and 2014. Multivariate analysis was utilized to identify high-risk subgroup membership as an independent predictor of postoperative complications.

RESULTS

Members of the elderly (≥65 years) (OR = 1.3, P = .02) and non-Caucasian (black, Hispanic, other) (OR = 1.7, P < .0001) subgroups were at greater risk for a LOS ≥5 days. Obese patients (≥30 kg/m² ) were at greater risk for an operative time ≥4 hours (OR = 1.3, P = .005), and wound complications (OR = 1.8, P = .024) compared with nonobese patients. Emergent procedures had a significantly increased risk for LOS ≥5 days (OR = 4.9, P = .021), sepsis (OR = 14.8, P = .018), and reoperation (OR = 13.4, P < .0001) compared with nonemergent procedures. Disseminated cancer was an independent risk factor for operative time ≥4 hours (OR = 8.4, P < .0001), LOS ≥5 days (OR = 15.2, P < .0001), pulmonary complications (OR = 7.4, P = .019), and postoperative blood transfusion (OR = 3.1, P = .040).

CONCLUSIONS

High-risk subgroup membership is an independent risk factor for morbidity following ALF. These groups should be targets for aggressive preoperative optimization, and quality improvement initiatives.

Red blood cell transfusion in surgical cancer patients: Targets, risks, mechanistic understanding and further therapeutic opportunities

Anemia is present in more than half of cancer patients and appears to be an independent prognostic factor of short- and long-term adverse outcomes. It increases in the advanced period of cancer and perioperatively, in patients with solid tumors who undergo surgery. As a result, allogeneic red blood cell (RBC) transfusion is an indispensable treatment in cancer. However, its safety remains controversial, based on several laboratory and clinical data reporting a linkage with increased risk for cancer recurrence, infection and cancer-related mortality. Immunological, inflammatory and thrombotic reactions mediated by the residual leukocytes and platelets, the stored RBCs per se, the biological response modifiers and the plasticizer of the unit may underlie infection and tumor-promoting effects. Although the causality between transfusion and infection has been established, the effects of transfusion on cancer recurrence remain confusing; this is mainly due to the extreme biological heterogeneity that characterizes RBC donations and cancer context. In fact, the functional interplay between donation-associated factors and recipient characteristics, including tumor biology per se, inflammation, infection, coagulation and immune activation state and competence may synergistically and individually define the clinical impact of each transfusion in any given cancer patient. Our understanding of how the potential risk is mediated is important to make RBC transfusion safer and to pave the way for novel, promising and highly personalized strategies for the treatment of anemia in surgical cancer patients.

Massive blood loss in elective spinal and orthopedic surgery: Retrospective review of intraoperative transfusion strategy

OBJECTIVE

To evaluate the perioperative dynamics of hematologic changes and transfusion ratio in patients undergoing a major spinal surgery accompanied with massive bleeding defined as blood loss >5 liters.

DESIGN

Retrospective cohort study.

SETTING

Operating room of a university-affiliated hospital.

PATIENTS

Adult patients who underwent elective neurosurgical, orthopedic, or combined spinal surgical procedure between 2008 and 2012.

METHODS

Patients who underwent a major spinal or orthopedic surgery and who experienced major bleeding (>5 L) during surgery were identified and selected for final analysis. The following information was analyzed: demographics, clinical diagnoses, hematologic parameters, estimated intraoperative blood loss, blood product transfusions, and survival 1 year after surgery.

RESULTS

During the study period, 25 patients, who underwent 28 spinal procedures, experienced intraoperative blood loss >5 L. Mean patient age was 50.5 years and 56.4% were males. The majority of patients underwent procedures to manage spinal metastases. Median estimated intraoperative blood loss was 11.25 L (IQR 6.35-22 L) and median number of units (U) transfused was 24.5 U (IQR 14.0-32.5 U) of packed red blood cells (RBCs), 24.5 U (IQR 14.0-34.0 U) of fresh frozen plasma (FFP), and 4.5 U (IQR 3.0-11.5 U) of platelets (PLTs). The blood product transfusion ratio was 1 and 4 for RBC:FFP, and RBC:PLT, respectively. Hematocrit, hemoglobin, PLTs, partial thromboplastin, prothrombin time, INR, and, fibrinogen varied significantly throughout the procedures. However, acid-base status did not change significantly during surgery. Patients' survival at 1 year was 79.17%.

CONCLUSION

Our results indicate that a 1:1 RBC:FFP and 4:1 RBC:PLT transfusion ratio was associated with significant intraoperative variations in coagulation variables but stable intraoperative acid-base parameters. This transfusion ratio helped clinicians to achieve postoperative coagulation parameters not significantly different to those at baseline. Future studies should assess if more liberal transfusion strategies or point of care monitoring might be warranted in patients undergoing spinal surgery at risk of major blood loss.

Perioperative blood transfusion: does it influence survival and cancer progression in metastatic spine tumor surgery?

BACKGROUND

Despite advances in surgical techniques for spinal metastases, there is often substantial blood loss, resulting in patients requiring blood transfusion during the perioperative period. Allogeneic blood transfusion (ABT) has been the main replenishment method for lost blood. However, the impact of ABT on cancer-related outcomes has been controversial in various studies. We aimed to evaluate the influence of perioperative ABT on disease progression and survival in patients undergoing metastatic spinal tumor surgery (MSTS).

STUDY DESIGN AND METHODS

We conducted a retrospective study that included 247 patients who underwent MSTS at a single tertiary institution between 2005 and 2014. The impact of using perioperative ABT (either exposure to or quantities of transfusion) on disease progression and survival was assessed using Cox regression analyses while adjusting for potential confounding variables.

RESULTS

Of 247 patients, 133 (54%) received ABT. The overall median number of blood units transfused was 2 (range, 0-10 units). Neither blood transfusion exposure nor quantities of transfusion were associated with overall survival (hazard ratio [HR], 1.15 [p = 0.35] and 1.10 [p = 0.11], respectively) and progression-free survival (HR, 0.87 [p = 0.18] and 0.98 [p = 0.11], respectively). The factors that influenced overall survival were primary tumor type and preoperative Eastern Cooperative Oncology Group performance status, whereas primary tumor type was the only factor that had an impact on progression-free survival.

CONCLUSIONS

This is the first study providing evidence that disease progression and survival in patients who undergo MSTS are less likely to be influenced by perioperative ABT. The worst oncologic outcomes are more likely to be caused by the clinical circumstances necessitating blood transfusion, but not transfusion itself. However, because ABT can have a propensity toward developing postoperative infections, including surgical site infection, the use of patient blood management interventions would be worthwhile rather than relying solely on ABTs for these patients, if and whenever possible.