Predictors of transfusion for spinal surgery in Maryland, 1997 to 2000

Prevalence, Risk Factors, and Postoperative Infection Rates of Blood Transfusion in Lumbar Spinal Fusion Surgery: A Nationwide Population-Based Study

Study Design: Retrospective cohort study. Objectives: Effects of blood loss that requires blood transfusion after lumbar spinal fusion remain an important issue. Blood transfusions are used commonly in cases of significant blood loss in lumbar spinal fusion but are associated with adverse effects. The objective was to assess the rate of blood transfusion and the associated risk after lumbar spinal fusion from 2013 to 2018. Methods: In this nationwide population-based cohort study, the Korean Health Insurance Review and Assessment Service database was reviewed retrospectively from 2013 to 2018. Data were extracted from patients who underwent lumbar spinal fusion without history of lumbar spinal surgery in the preceding year. The primary outcome was the rate of blood transfusion within 1 week of surgery. In addition, the risk factors for blood transfusion and the rate of postoperative infection were evaluated. Results: A total of 188,581 patients underwent lumbar spinal fusion between 2013 and 2018. A significant decline in blood transfusions was observed during the study period (56.38-47.51%). The presence of comorbidities was associated with an increased risk of blood transfusion. Patients who underwent the posterior approach were more likely to receive blood transfusion than patients who underwent the anterior or anterior and posterior approach. Receiving blood transfusion was associated with postoperative infection. Conclusions: In the present study, the prevalence, risk factors, and postoperative infection rates associated with blood transfusion in lumbar spinal fusion were identified. Spine surgeons should consider these risk factors in patients at high risk of blood transfusion.

Effect of oral tranexamic acid on postoperative bleeding in spinal surgery: a randomized controlled trial

Background and objective

This study aimed to investigate the effect of oral administration of tranexamic acid (TXA) on reducing intraoperative bleeding during spinal surgeries.

Method

The study was a single-center, double-blind, randomized, placebo-controlled clinical trial. Participants were individuals over 20 years old who underwent spinal surgery. Patients received 1.5 g of TXA orally, 2 h before surgery. Intraoperative bleeding volume, blood volume in the drain after surgery, length of hospital stays after surgery, incidence of nausea or vomiting, decrease in hemoglobin (Hb) level, and postoperative coagulation test results were evaluated in each group.

Results

In this study, patients were assigned to each study group based on inclusion and exclusion criteria. The mean age of patients was 69.6±6.47 years, and 65% were male. There was no significant difference in age, sex, pre and postoperative Hb levels, prothrombin time (PT), or international normalized ratio (INR) between the study groups. Intraoperative bleeding volume and blood volume in the drain after surgery were significantly lower in the TXA group. Additionally, the length of hospital stay after surgery was significantly shorter in the TXA group. The incidence of nausea or vomiting was significantly higher in the TXA group. Furthermore, postoperative partial thromboplastin time (PTT) was significantly higher in the TXA group compared to the placebo group.

Conclusion

Oral administration of TXA before spinal surgery leads to a significant reduction in intraoperative and postoperative bleeding without significant adverse effects and also reduces the length of hospital stay.

Predictors of Blood Transfusion in Patients Undergoing Lumbar Spinal Fusion

OBJECTIVE

To determine risk factors for perioperative blood transfusion after lumbar fusion surgery.

METHODS

After institutional review board approval, a retrospective cohort study of adult patients who underwent lumbar fusion at a single, urban tertiary academic center was retrospectively retrieved. Our primary outcome, blood transfusion, was collected via chart query. A receiver operating characteristic curve was used to evaluate the regression model. A P-value < 0.05 was considered statistically significant.

RESULTS

Of the 3,842 patients, 282 (7.3%) required a blood transfusion. For patients undergoing posterolateral decompression and fusion, predictors of transfusion included age (P < 0.001) and more levels fused (P < 0.001). A higher preoperative hemoglobin level (P < 0.001) and revision surgery (P = 0.005) were protective of blood transfusion. For patients undergoing transforaminal lumbar interbody fusion, greater Elixhauser comorbidity index (P < 0.001), longer operative time (P = 0.040), and more levels fused (P = 0.030) were independent predictors of the need for blood transfusion. Patients with a higher body mass index (P = 0.012) and preoperative hemoglobin level (P < 0.001) had a reduced likelihood of receiving a transfusion. For circumferential fusion, greater age (P = 0.006) and longer operative times (P = 0.015) were independent predictors of blood transfusion, while a higher preoperative hemoglobin level (P < 0.001) and male sex (P = 0.002) were protective.

CONCLUSIONS

Our analysis identified older age, lower body mass index, greater Elixhauser comorbidity index, longer operative duration, more levels fused, and lower preoperative hemoglobin levels as independent predictors of requiring a blood transfusion following lumbar spinal fusion. Different surgical approaches were not found to be associated with transfusion.

Risk Factors for 30-day Unplanned Readmission following Surgery for Lumbar Degenerative Diseases: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVES

Surgical procedures for lumbar degenerative diseases (LDD), which have emerged in the 21-century, are commonly practiced worldwide. Regarding financial burdens and health costs, readmissions within 30days following surgery are inconvenient. We performed a systematic review to integrate real-world evidence and report the current risk factors associated with 30-day readmission following surgery for LDD.

METHODS

The Cochrane Library, Embase, and Medline electronic databases were searched from inception to April 2022 to identify relevant studies reporting risk factors for 30-day readmission following surgery for LDD.

RESULTS

Thirty-six studies were included in the review. Potential risk factors were identified in the included studies that reported multivariate analysis results, including age, race, obesity, higher American Society of Anesthesiologists score, anemia, bleeding disorder, chronic pulmonary disease, heart failure, dependent status, depression, diabetes, frailty, malnutrition, chronic steroid use, surgeries with anterior approach, multilevel spinal surgeries, perioperative transfusion, presence of postoperative complications, prolonged operative time, and prolonged length of stay.

CONCLUSIONS

There are several potential perioperative risk factors associated with unplanned readmission following surgery for LDD. Preoperatively identifying patients that are at increased risk of readmission is critical for achieving the best possible outcomes.

Perioperative transcutaneous electrical acupoint stimulation (pTEAS) in pain management in major spinal surgery patients

Background

Lumbar disc herniation is seen in 5–15% of patients with lumbar back pain and is the most common spine disorder demanding surgical correction. Spinal surgery is one of the most effective management for these patients. However, current surgical techniques still present complications such as chronic pain in 10–40% of all patients who underwent lumbar surgery, which has a significant impact on patients’ quality of life. Research studies have shown that transcutaneous electrical acupoint stimulation (TEAS) may reduce the cumulative dosage of intraoperative anesthetics as well as postoperative pain medications in these patients.

Objective

To investigate the effect of pTEAS on pain management and clinical outcome in major spinal surgery patients.

Methods

We conducted a prospective, randomized, double-blind study to verify the effect of pTEAS in improving pain management and clinical outcome after major spinal surgery. Patients (n = 90) who underwent posterior lumbar fusion surgery were randomized into two groups: pTEAS, (n = 45) and Control (n = 45). The pTEAS group received stimulation on acupoints Zusanli (ST.36), Sanyinjiao (SP.6), Taichong (LR.3), and Neiguan (PC.6). The Control group received the same electrode placement but with no electrical output. Postoperative pain scores, intraoperative outcome, perioperative hemodynamics, postoperative nausea and vomiting (PONV), and dizziness were recorded.

Results

Intraoperative outcomes of pTEAS group compared with Control: consumption of remifentanil was significantly lower (P < 0.05); heart rate was significantly lower at the end of the operation and after tracheal extubation (P < 0.05); and there was lesser blood loss (P < 0.05). Postoperative outcomes: lower pain visual analogue scale (VAS) score during the first two days after surgery (P < 0.05); and a significantly lower rate of PONV (on postoperative Day-5) and dizziness (on postoperative Day-1 and Day-5) (P < 0.05).

Conclusion

pTEAS could manage pain effectively and improve clinical outcomes. It could be used as a complementary technique for short-term pain management, especially in patients undergoing major surgeries.

Trial registration

ChiCTR1800014634, retrospectively registered on 25/01/2018. http://medresman.org/uc/projectsh/projectedit.aspx?proj=183

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01875-3

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.

Allogeneic blood transfusions and infection risk in lumbar spine surgery: An American College of Surgeons National Surgery Quality Improvement Program Study

BACKGROUND

Allogenic blood transfusions can lead to immunomodulation. Our purpose was to investigate whether perioperative transfusions were associated with postoperative infections and any other adverse events (AEs), after adjusting for potential confounding factors, following common elective lumbar spinal surgery procedures.

STUDY DESIGN AND METHODS

We performed a multivariate, propensity-score matched, regression-adjusted retrospective analysis of the American College of Surgeons National Surgical Quality Improvement Program database between 2012 and 2016. All lumbar spinal surgery procedures were identified (n = 174,891). A transfusion group (perioperative transfusion within 72 h before, during, or after principal surgery; n = 1992) and a control group (no transfusion; n = 1992) were formed. Following adjustment for between-group baseline features, adjusted odds ratios (aOR) and 95% confidence intervals (95% CI) were calculated using a multivariate logistic regression model for any surgical site infection (SSI), superficial SSI, deep SSI, wound dehiscence, pneumonia, urinary tract infection, sepsis, any infection, mortality, and any AEs.

RESULTS

Transfusion was associated with an increased risk of each specific infection, mortality, and any AEs. Statistically significant between-group differences were demonstrated with respect to any SSI (aOR: 1.48; 95% CI: 1.01-2.16), deep SSI (aOR: 1.66; 95% CI: 0.98-2.85), sepsis (aOR: 2.69; 95% CI: 1.43-5.03), wound dehiscence (aOR: 2.27; 95% CI: 0.86-6.01), any infection (aOR: 1.46; 95% CI: 1.13-1.88), any AEs (aOR: 1.80; 95% CI: 1.48-2.18), and mortality (aOR: 2.17; 95% CI: 0.77-6.36).

CONCLUSION

We showed an association between transfusion and infection in lumbar spine surgery after adjustment for various applicable covariates. Sepsis had the highest association with transfusion. Our results reinforce a growing trend toward minimizing perioperative transfusions, which may lead to reduced infections following lumbar spine surgery.

Hemostats in Spine Surgery: Literature Review and Expert Panel Recommendations

Bleeding in spine surgery is a common occurrence but when bleeding is uncontrolled the consequences can be severe due to the potential for spinal cord compression and damage to the central nervous system. There are many factors that influence bleeding during spine surgery including patient factors and those related to the type of surgery and the surgical approach to bleeding. There are a range of methods that can be employed to both reduce the risk of bleeding and achieve hemostasis, one of which is the adjunct use of hemostatic agents. Hemostatic agents are available in a variety of forms and materials and with considerable variation in cost, but specific evidence to support their use in spine surgery is sparse. A literature review was conducted to identify the pre-, peri-, and postsurgical considerations around bleeding in spine surgery. The review generated a set of recommendations that were discussed and ratified by a wider expert group of spine surgeons. The results are intended to provide a practical guide to the selection of hemostats for specific bleeding situations that may be encountered in spine surgery.

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.

Complications After Adult Spinal Deformity Surgeries: All Are Not Created Equal

BACKGROUND

Data on timing of complications are important for accurate quality assessments. We sought to better define pre- and postdischarge complications occurring within 90 days of adult spinal deformity (ASD) surgery and quantify the effect of multiple complications on recovery.

METHODS

We performed a review of 1040 patients who underwent ASD surgery (age: 46 ± 23; body mass index: 25 ± 7, American Society of Anesthesiologists [ASA] score: 2.5 ± 0.6, levels: 10 ± 4, revision: 9%, 3-column osteotomy: 13%). We assessed pre- and postdischarge complications and risk factors for isolated versus multiple complications, as well as the impact of multiple complications.

RESULTS

The 90-day complication rate was 17.7%. 85 patients (8.2%) developed a predischarge complication, most commonly ileus (12%), and pulmonary embolism (PE; 7.1%). The most common causes of predischarge unplanned reoperation were neurologic injury (12.9%) and surgical site drainage (8.2%). Predictors of a predischarge complication included smoking (odds ratio [OR]: 2.2, P = .02), higher ASA (OR: 1.8, P = .008), hypertension (HTN; OR: 2.0, P = .004), and iliac fixation (OR: 4.3, P < .001). Ninety-nine patients (9.5%) developed a postdischarge complication, most commonly infection (34%), instrumentation failure (13.4%), and proximal junctional failure (10.4%). Predictors of postdischarge complications included chronic obstructive pulmonary disease (OR: 3.6, P < .0001), congestive heart failure (OR: 4.4, P = .016), HTN (OR: 2.3, P < .0001), and multiple rod construct (OR: 1.8, P = .02). Patients who developed multiple complications (9.3%) had a longer length of stay, and increased risk for readmission and unplanned reoperation.

CONCLUSIONS

Knowledge regarding timing of postoperative complications in relation to discharge may better inform quality improvement measures. PE and implant-related complications play a prominent role in perioperative complications and need for readmission, with several modifiable risk factors identified.

LEVEL OF EVIDENCE

Level 3.

CLINICAL RELEVANCE

Advances in surgical techniques and instrumentation have improved postoperative radiographic and clinical outcomes after ASD surgery. The rate of complications after complex ASD surgery remains high, both at early postoperative and long term follow-up. This study reviews complications within 90 days of surgery, with an assessment of patient and surgical risk factors. We found that modifiable risk factors for early complications after ASD surgery include COPD, and current smoking. The data presented in this study also provide surgeons with knowledge of the most common complications encountered after ASD surgery, to aid in preoperative patient discussion.

Impact of Preoperative Platelet Count on Bleeding Risk and Allogeneic Transfusion in Multilevel Spine Surgery

STUDY DESIGN

This was an observational cohort study of patients receiving multilevel thoracic and lumbar spine surgery.

OBJECTIVE

The aim of this study was to identify which patients are at high risk for allogeneic transfusion which may allow for better preoperative planning and employment of specific blood management strategies.

SUMMARY OF BACKGROUND DATA

Multilevel posterior spine surgery is associated with a significant risk for major blood loss, and allogeneic blood transfusion is common in spine surgery.

METHODS

A univariate logistic regression model was used to identify variables that were significantly associated with intraoperative allogeneic transfusion. A multivariate forward stepwise logistic regression model was then used to measure the adjusted association of these variables with intraoperative transfusion.

RESULTS

Multilevel thoracic and lumbar spine surgery was performed in 921 patients. When stratifying patients by preoperative platelet count, patients with pre-operative thrombocytopenia and severe thrombocytopenia had a significantly higher rate of transfusion than those who were not thrombocytopenic. Furthermore, those with severe thrombocytopenia had a higher rate of red blood cells, fresh frozen plasma, and platelet transfusion than those with higher platelet counts. Multivariate logistic regression found that preoperative platelet count was the most significant contributor to transfusion, with a platelet count ≤100 having an adjusted odds ratio (OR) of transfusion of 4.88 (95% confidence interval [CI] 1.58-15.02, P = 0.006). Similarly, a platelet count between 101and 150 also doubled the risk of transfusion with an adjusted OR of 2.02 (95% CI 1.01-4.04, P = 0.047). The American Society of Anesthesiologists classification score increased the OR of transfusion by 2.5 times (OR = 2.52, 95% CI 1.54-4.13), whereas preoperative prothrombin time and age minimally increased the risk.

CONCLUSION

Preoperative thrombocytopenia significantly contributes to intraoperative transfusion in multilevel thoracic lumbar spine surgery. Identifying factors that may increase the risk for transfusion could be of great benefit in better preoperative counseling of patients and in reducing overall cost and postoperative complications by implementing strategies and techniques to reduce blood loss and blood transfusions.

LEVEL OF EVIDENCE

2.

Risk Factors for Wound-Related Complications After Surgery for Primary and Metastatic Spine Tumors: A Systematic Review and Meta-Analysis

OBJECTIVE

We systematically reviewed the literature to compare risk factors for postoperative complications at the surgical wound site in primary and metastatic tumor operations.

METHODS

We screened English-language publications on the outcomes of primary and metastatic spinal tumor operations. Pooled analyses and meta-analyses with random-effects modeling were performed comparing patients with and without wound complications, which were defined as surgical site infection or sterile wound dehiscence.

RESULTS

Our search identified 5471 unique citations, from which we included 23 studies describing 5104 patients. A total of 1936 patients underwent surgery for primary tumors, with a wound complication rate of 8.1%. Subgroup analysis of benign and malignant primary tumors yielded significantly different wound complication rates of 7.8% and 26.9%, respectively. The metastatic tumor cohort included 168 patients and a complication rate of 6.6%. In a pooled analysis of primary tumors, higher wound complication rates were associated with sacral operations and the use of instrumentation. In the metastatic tumor cohort, higher complication rates were associated with female sex, smoking history, preoperative chemotherapy, preoperative radiotherapy, corticosteroid use, and previous spine surgery. Instrumentation remained a statistically significant risk factor for primary tumors with the addition of random-effects meta-analysis.

CONCLUSIONS

Risk factors for wound complications after primary tumor operations were related to tumor histology and the spinal location of the operation. Risk factors for metastatic tumors may be related to several systemic preoperative treatments and baseline comorbidities. Random-effects meta-analysis showed the limited generalizability of these findings because of the small heterogenous primary literature.

Decision Tree-based Modelling for Identification of Predictors of Blood Loss and Transfusion Requirement After Adult Spinal Deformity Surgery

Background

Multilevel fusions and complex osteotomies to restore global alignment in adult spinal deformity (ASD) surgery can lead to increased operative time and blood loss. In this regard, we assessed factors predictive of perioperative blood product transfusion in patients undergoing long posterior spinal fusion for ASD.

Methods

A single-institution retrospective review was conducted on 909 patients with ASD, age > 18 years, who underwent surgery for ASD with greater than 4 levels fused. Using conditional inference tree analysis, a machine learning methodology, we sought to predict the combination of variables that best predicted increased risk for intraoperative percent blood volume lost and perioperative blood product transfusion.

Results

Among the 909 patients included in the study, 377 (41.5%) received red blood cell (RBC) transfusion. The conditional inference tree analysis identified greater than 13 levels fused, American Society of Anesthesiologists (ASA) score > 1, a history of hypertension, 3-column osteotomy, pelvic fixation, and operative time > 8 hours, as significant risk factors for perioperative RBC transfusion. The best predictors for the subgroup with the highest risk for intraoperative percent blood volume lost (subgroup mean: 53.1% ± 42.9%) were greater than 13 levels fused, ASA score > 1, preoperative hemoglobin < 13.6 g/dL, 3-column osteotomy, posterior column osteotomy, and pelvic fixation. Patients who underwent major blood transfusion intraoperatively had significantly longer length of stay (8.5 days) versus those who did not (6.1 days) (P < .0001). The overall 90-day complication rate in patients who underwent major blood transfusion intraoperatively was 49%, compared with 19% in those who did not (P < .0001). By multivariate regression analysis, patients with a preoperative hemoglobin > 13.0 were less likely to require major blood transfusion (odds ratio: 0.52, P = .046).

Conclusions

Using a supervised learning technique, this study demonstrates that greater than 13 levels fused, ASA score > 1, 3-column osteotomy, and pelvic fixation are consistent risk factors for increased intraoperative percent blood volume lost and perioperative RBC transfusion. The addition of having a preoperative hemoglobin < 13.6 g/dL or undergoing a posterior column osteotomy conferred the highest risk for intraoperative blood loss. This information can assist spinal deformity surgeons in identifying at-risk individuals and allocating healthcare resources.

Level of Evidence

3.

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.

Is blood transfusion associated with an increased risk of infection among spine surgery patients?: A meta-analysis

BACKGROUND

Blood transfusions are associated with many adverse outcomes among spine surgery patients, but it remains unclear whether perioperative blood transfusion during spine surgery and postoperative infection are related. Recently, many related cohort studies have been published on this topic.

METHODS

This study was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The PubMed, Embase, and Cochrane Library databases were searched for eligible published studies. The Newcastle-Ottawa Scale (NOS) was used to assess the methodological quality of the studies, and a random-effects model was used to calculate the odds ratios (ORs) with 95% CIs. Sensitivity analyses were conducted to explore the source of heterogeneity.

RESULTS

The final analysis included 8 cohort studies with a total of 34,185 spine surgery patients. These studies were considered to be of high or moderate quality based on their NOS scores, which ranged from 5 to 9. Pooled estimates indicated that blood transfusion increased the infection rate (OR, 2.99; 95% CI, 1.95 to 4.59; I = 86%), which was consistent with the sensitivity analyses.

CONCLUSIONS

Our results suggest that perioperative blood transfusion is a risk factor for postoperative infection among spine surgery patients. Further study is necessary to identify other influencing factors and to establish the mechanism underlying this relationship. Additional measures may be needed to reduce unnecessary blood transfusions during spine surgery.

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.

Hypoalbuminemia as an Independent Risk Factor for Perioperative Complications Following Surgical Decompression of Spinal Metastases

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Malnutrition has been shown to be a risk factor for poor perioperative outcomes in multiple surgical subspecialties, but few studies have specifically investigated the effect of hypoalbuminemia in patients undergoing operative treatment of metastatic spinal tumors. The aim of this study was to assess the role of hypoalbuminemia as an independent risk factor for 30-day perioperative mortality and morbidity after surgical decompression of metastatic spinal tumors using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2011 to 2014.

METHODS

We identified 1498 adult patients in the ACS-NSQIP database who underwent laminectomy and excision of metastatic extradural spinal tumors. Patients were categorized into normoalbuminemic and hypoalbuminemic (ie, albumin level <3.5 g/dL) groups. Univariate and multivariate regression analyses were performed to examine the association between preoperative hypoalbuminemia and 30-day perioperative mortality and morbidity. Subgroup analysis was performed in the hypoalbuminemic group to assess the dose-dependent effect of albumin depletion.

RESULTS

Hypoalbuminemia was associated with increased risk of perioperative mortality, any complication, sepsis, intra- or postoperative transfusion, prolonged hospitalization, and non-home discharge. However, albumin depletion was also associated with decreased risk of readmission. There was an albumin level-dependent effect of increasing mortality and complication rates with worsening albumin depletion.

CONCLUSIONS

Hypoalbuminemia is an independent risk factor for perioperative mortality and morbidity following surgical decompression of metastatic spinal tumors with a dose-dependent effect on mortality and complication rates. Therefore, it is important to address malnutrition and optimize nutritional status prior to surgery.

Clinical Efficacy of Intra-Operative Cell Salvage System in Major Spinal Deformity Surgery

Objective

The purpose of this study was to determine the efficacy of intra-operative cell salvage system (ICS) to decrease the need for allogeneic transfusions in patients undergoing major spinal deformity surgeries.

Methods

A total of 113 consecutive patients undergoing long level posterior spinal segmental instrumented fusion (≥5 levels) for spinal deformity correction were enrolled. Data including the osteotomy status, the number of fused segments, estimated blood loss, intra-operative transfusion amount by ICS (Cell Saver^®, Haemonetics^©, Baltimore, MA, USA) or allogeneic blood, postoperative transfusion amount, and operative time were collected and analyzed.

Results

The number of patients was 81 in ICS group and 32 in non-ICS group. There were no significant differences in demographic data and comorbidities between the groups. Autotransfusion by ICS system was performed in 53 patients out of 81 in the ICS group (65.4%) and the amount of transfused blood by ICS was 226.7 mL in ICS group. The mean intra-operative allogeneic blood transfusion requirement was significantly lower in the ICS group than non-ICS group (2.0 vs. 2.9 units, p=0.033). The regression coefficient of ICS use was -1.036.

Conclusion

ICS use could decrease the need for intra-operative allogeneic blood transfusion. Specifically, the use of ICS may reduce about one unit amount of allogeneic transfusion in major spinal deformity surgery.

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.

Transfusion of Red Blood Cells Stored More Than 28 Days is Associated With Increased Morbidity Following Spine Surgery

STUDY DESIGN

A retrospective study.

OBJECTIVE

The aim of this study was to describe the association between storage duration of packed red blood cells (PRBCs) and perioperative adverse events in patients undergoing spine surgery at a tertiary care center.

SUMMARY OF BACKGROUND DATA

Despite retrospective studies that have shown that longer PRBC storage duration worsens patient outcomes, randomized clinical trials have found no difference in outcomes. However, no studies have examined the impact of giving the oldest blood (28 days old or more) on morbidity within spine surgery.

METHODS

The surgical administrative database at our institution was queried for patients transfused with PRBCs who underwent spine surgery between December 4, 2008, and June 26, 2015. Patients undergoing spinal fusion, tumor-related surgeries, and other identified spine surgeries were included. Patients were divided into two groups on the basis of storage duration of blood transfused: exclusively ≤28 days' storage or exclusively >28 days' storage. The primary outcome was composite in-hospital morbidity, which included (1) infection, (2) thrombotic event, (3) renal injury, (4) respiratory event, and/or (5) ischemic event.

RESULTS

In total, 1141 patients who received a transfusion were included for analysis in this retrospective study; 710 were transfused exclusively with PRBCs ≤28 days' storage and 431 exclusively with PRBCs >28 days' storage. Perioperative complications occurred in 119 patients (10.4%). Patients who received blood stored for >28 days had higher odds of developing any one complication [odds ratio (OR) = 1.82; 95% confidence interval (95% CI), 1.20-2.74; P = 0.005] even after adjusting for competing perioperative risk factors.

CONCLUSION

Blood stored for >28 days is independently associated with higher odds of developing perioperative complications in patients transfused during spinal surgery. Our results suggest that blood storage duration may be an appropriate parameter to consider when developing institutional transfusion guidelines that seek to optimize patient outcomes.

LEVEL OF EVIDENCE

3.

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

(1) Background: This study evaluated the perioperative red blood cell (RBC) transfusion need and determined predictors for transfusion in patients undergoing elective primary lumbar posterior spine fusion in a high-volume center for spine surgery. (2) Methods: Data from all patients undergoing spine surgery between 1 January 2014 and 31 December 2016 were reviewed. Patients’ demographics and comorbidities, perioperative laboratory results, and operative time were analyzed in relation to RBC transfusion. Multivariate logistic regression analysis was performed to identify the predictors of transfusion. (3) Results: A total of 874 elective surgeries for primary spine fusion were performed over the three years. Only 54 cases (6%) required RBC transfusion. Compared to the non-transfused patients, transfused patients were mainly female (p = 0.0008), significantly older, with a higher ASA grade (p = 0.0002), and with lower pre-surgery hemoglobin (HB) level and hematocrit (p < 0.0001). In the multivariate logistic regression, a lower pre-surgery HB (OR (95% CI) 2.84 (2.11–3.82)), a higher ASA class (1.77 (1.03–3.05)) and a longer operative time (1.02 (1.01–1.02)) were independently associated with RBC transfusion. (4) Conclusions: In the instance of elective surgery for primary posterior lumbar fusion in a high-volume center for spine surgery, the need for RBC transfusion is low. Factors anticipating transfusion should be taken into consideration in the patient’s pre-surgery preparation.

Effect of liberal blood transfusion on clinical outcomes and cost in spine surgery patients

BACKGROUND CONTEXT

Blood transfusions in spine surgery are shown to be associated with increased patient morbidity. The association between transfusion performed using a liberal hemoglobin (Hb) trigger-defined as an intraoperative Hb level of ≥10 g/dL, a postoperative level of ≥8 g/dL, or a whole hospital nadir between 8 and 10 g/dL-and perioperative morbidity and cost in spine surgery patients is unknown and thus was investigated in this study.

PURPOSE

This study aimed to describe the perioperative outcomes and economic cost associated with liberal Hb trigger transfusion among spine surgery patients.

STUDY DESIGN/SETTING

This is a retrospective study.

PATIENT SAMPLE

The surgical billing database at our institution was queried for inpatients discharged between 2008 and 2015 after the following procedures: atlantoaxial fusion, anterior cervical fusion, posterior cervical fusion, anterior lumbar fusion, posterior lumbar fusion, lateral lumbar fusion, other procedures, and tumor-related surgeries. In total, 6,931 patients were included for analysis.

OUTCOME MEASURES

The primary outcome was composite morbidity, which was composed of (1) infection (sepsis, surgical-site infection, Clostridium difficile infection, or drug-resistant infection); (2) thrombotic event (pulmonary embolus, deep venous thrombosis, or disseminated intravascular coagulation); (3) kidney injury; (4) respiratory event; and (5) ischemic event (transient ischemic attack, myocardial infarction, or cerebrovascular accident).

MATERIALS AND METHODS

Data on intraoperative transfusion were obtained from an automated, prospectively collected anesthesia data management system. Data on postoperative hospital transfusion were obtained through a Web-based intelligence portal. Based on previous research, we analyzed the data using three definitions of a liberal transfusion trigger in patients who underwent red blood cell transfusion: a liberal intraoperative Hb trigger as a nadir Hb level of 10 g/dL or greater, a liberal postoperative Hb trigger as a nadir Hb level of 8 g/dL or greater, or a whole hospital nadir Hb level of 8-10 g/dL. Variables analyzed included in-hospital morbidity, mortality, length of stay, and total costs associated with a liberal transfusion strategy.

RESULTS

Among patients with a whole hospital stay nadir Hb between 8 and 10 g/dL, transfused patients demonstrated a longer in-hospital stay (median [interquartile range], 6 [5-9] vs. 4 [3-6] days; p<.0001) and a higher perioperative morbidity (n=145 [11.5%] vs. n=74 [6.1%], p<.0001) than those not transfused. Even after adjusting for age, gender, race, American Society of Anesthesiologists class, Charlson Comorbidity Index score, estimated blood loss, baseline Hb value, and surgery type, logistic regression analysis revealed that patients with a nadir Hb of 8-10 g/dL who were transfused had an independently higher risk of perioperative morbidity (odds ratio=2.11, 95% confidence interval, 1.44-3.09; p<.0001). Estimated additional costs associated with liberal trigger use, defined as a transfusion occurring in patients with a whole hospital stay nadir Hb of 8-10 g/dL, ranged from $202,675 to $700,151 annually.

CONCLUSIONS

Transfusion using a liberal trigger is associated with increased morbidity, even after controlling for possible confounders. Our results suggest that modification of transfusion practice may be a potential area for improving patient outcomes and reducing costs.

Association Between Allogeneic Blood Transfusion and Postoperative Infection in Major Spine Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The objective of this study is to compare the incidence of infection in patients who do and do not receive blood transfusions in major deformity surgery (>8 levels).

SUMMARY OF BACKGROUND DATA

Postoperative infections increase morbidity and mortality rates in spine surgery and generate additional costs for the health care system. It has been proposed that blood transfusions increase the risk of wound infection, urinary tract infection, pneumonia, and sepsis.

METHODS

A total of 56 patients met the study criteria, receiving spine surgery involving the fusion of 8 levels or more. Patient-specific characteristics, starting and ending hematocrits, number of units transfused and infections including urinary tract infection, wound infection, pneumonia, and sepsis were documented. Differences in infection risk between those who did and did not undergo a transfusion and their 95% confidence intervals were calculated.

RESULTS

Groups were similar with respect to baseline and surgical characteristics except for smoking status, operative time, estimated blood loss, and ending hematocrit. The overall infection rate was greater in patients who underwent transfusion than those who did not (36% vs. 10%; P=0.03). Wound infections (n=5) were only observed in those who underwent a transfusion. Smokers were more likely to receive a transfusion and more likely to experience infection. A stratified analysis demonstrated an increased risk of infection associated with transfusion; however, the risk was greater in smokers, suggesting the effect of transfusion on infection could be modified by smoking. Patients undergoing transfusion experienced a significantly longer hospital stay (P=0.01).

CONCLUSIONS

Allogeneic red blood cell transfusion in major spine surgery could be a risk factor for postoperative infection. This increased risk seems to be magnified in those who smoke. Further studies are warranted, and risks of blood loss and transfusion-related complications in smokers also potentially merit exploration.

LEVEL OF EVIDENCE

Level 3.

Incidence, Predictors, and Postoperative Complications of Blood Transfusion in Thoracic and Lumbar Fusion Surgery: An Analysis of 13,695 Patients from the American College of Surgeons National Surgical Quality Improvement Program Database

Study Design Retrospective cohort study. Objective To identify predictive factors for blood transfusion and associated complications in lumbar and thoracic fusion surgeries. Methods The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was used to identify patients who underwent lumbar or thoracic fusion from 2010 to 2013. Multivariate analysis was used to determine predictive factors and postoperative complications associated with transfusion. Results Out of 13,695 patients, 13,170 had lumbar fusion and 525 had thoracic fusion. The prevalence of transfusion was 31.8% for thoracic and 17.0% for lumbar fusion. The multivariate analysis showed that age between 50 and 60, age between 61 and 70, age > 70, dyspnea, American Society of Anesthesiologists class 3, bleeding disease, multilevel surgery, extended surgical time, return to operation room, and higher preoperative blood urea nitrogen (BUN) were predictors of blood transfusion for lumbar fusion. Multilevel surgery, preoperative BUN, and extended surgical time were predictors of transfusion for thoracic fusion. Patients receiving transfusions who underwent lumbar fusion were more likely to develop wound infection, venous thromboembolism, pulmonary embolism, and myocardial infarction and had longer hospital stay. Patients receiving transfusions who underwent thoracic fusion were more likely to have extended hospital stay. Conclusion This study characterizes incidence, predictors, and postoperative complications associated with blood transfusion in thoracic and lumbar fusion. Pre- and postoperative planning for patients deemed to be at high risk of requiring blood transfusion might reduce postoperative complications in this population.

Pre-Operative Autologous Blood Donation Does Not Affect Pre-Incision Hematocrit in Adolescent Idiopathic Scoliosis Patients. A Retrospective Cohort of a Prospective Randomized Trial

BACKGROUND

Pre-donation of autologous blood prior to spine fusion for adolescent idiopathic scoliosis (AIS) has been used in deformity surgery. The effect of pre-donation on pre-operative hematocrit (Hct) remains debated. Multiple factors may influence pre-operative Hct including intravascular volume status, patient factors, and timing of pre-operative blood donation. The purpose of this study was to determine if pre-donation significantly lowers pre-incision Hct in AIS patients.

METHODS

A retrospective cohort study of a Level-1 prospective randomized trial was conducted. 125 patients from the homogeneous population were included. AIS patients undergoing a posterior only spinal fusion for AIS were separated into two groups based on their pre-operative blood donation history. Demographic variables, pre-incision Hct, and transfusion rates were compared between the two groups using the Student's T-test.

RESULTS

Pre-donation and non pre-donation groups had 28 and 97 patients, respectively. Pre-donation group was 75% female (21F, 7M) and non pre-donation group was 78% female (76F, 21M). There was no difference between pre-donation and non pre-donation groups in mean age (15.6 ± 2.2 vs 14.8 ± 2.2, p = 0.081), BMI (23.1 ± 4.2 vs 21.7 ± 5.3, p = 0.219), and pre-incision Hct (32.8 ± 3.4 vs 33.8 ± 3.1, p = 0.628). The overall transfusion rates were equivalent (32.1± 48.0% vs 25.8 ± 44.0%, p = 0.509), however, the rate of allogenic transfusion for the pre-donation group was significantly lower (3.6 ± 18.9% vs 25.8 ± 44.0%, p = 0.011).

CONCLUSIONS

This study supports the use of pre-donation for AIS, without a significant drop in pre-incision Hct. Patients that donate are also much less likely to be exposed to allogenic blood. There may be a surgeon bias to recommend pre-donation in patients with a larger BMI and older age. Future studies are needed from a larger population of patients including those with non-AIS pathology.

LEVEL OF EVIDENCE

Level III.

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

BACKGROUND CONTEXT

Perioperative allogeneic blood transfusions have been associated with decreased survival after surgical resection of primary and metastatic cancer. Studies investigating this association for patients undergoing resection of bone metastases are scarce and controversial.

PURPOSE

We assessed (1) whether exposure to perioperative allogeneic blood transfusions was associated with decreased survival after surgery for spinal metastases and (2) if there was a dose-response relationship per unit of blood transfused. Additionally, we explored the risk factors associated with survival after surgery for spinal metastases.

STUDY DESIGN/SETTING

This is a retrospective cohort study from two university medical centers.

PATIENT SAMPLE

There were 649 patients who had operative treatment for metastatic disease of the spine between 2002 and 2014. Patients with lymphoma or multiple myeloma were also included. We excluded patients with a revision procedure, kyphoplasty, vertebroplasty, and radiosurgery alone.

OUTCOME MEASURES

The outcome measure was survival after surgery. The date of death was obtained from the Social Security Death Index and medical charts.

METHODS

Blood transfusions within 7 days before and 7 days after surgery were considered perioperative. A multivariate Cox proportional hazard model was used to assess the relationship between allogeneic blood transfusion as exposure versus non-exposure, and subsequently as continuous value; we accounted for clinical, laboratory, and treatment factors.

RESULTS

Four hundred fifty-three (70%) patients received perioperative blood transfusions, and the median number of units transfused was 3 (interquartile range: 2-6). Exposure to perioperative blood transfusion was not associated with decreased survival after accounting for all explanatory variables (hazard ratio [HR]: 1.03; 95% confidence interval [CI]: 0.80-1.31; p=.841). Neither did we find a dose-response relationship (HR: 1.01; 95% CI: 0.98-1.04; p=.420). Other factors associated with worse survival were older age, more severe comorbidity status, lower preoperativehemoglobin level, higher white blood cell count, higher calcium level, primary tumor type, previous systemic therapy, poor performance status, presence of lung, liver, or brain metastasis, and surgical approach.

CONCLUSIONS

Perioperative allogeneic blood transfusions were not associated with decreased survival after surgery for spinal metastases. More liberal transfusion policies might be warranted for patients undergoing surgery for spinal metastasis, although careful consideration is needed as other complications may occur.

Risk of infectious complications associated with blood transfusion in elective spinal surgery-a propensity score matched analysis

BACKGROUND CONTEXT

Although the negative aspects of blood transfusion are increasingly recognized, less is known about transfusion-related risks in spinal surgery.

PURPOSE

This study was designed to determine whether perioperative allogeneic blood transfusion is associated with increased risk of infectious complications after elective spinal surgery.

STUDY DESIGN

A retrospective cohort study with propensity score matched analysis was carried out.

PATIENT SAMPLE

Data of patients with spinal canal stenosis and spondylolisthesis who underwent elective lumbar surgeries (decompression or fusion) were obtained from the Diagnosis Procedure Combination database, a nationwide administrative inpatient database in Japan.

OUTCOME MEASURES

Clinical outcomes included in-hospital death and the occurrence of infectious complications (surgical site infection [SSI], respiratory tract infection, urinary tract infection, and sepsis).

METHODS

Patients' clinical information, including sex, age, type of hospital, preoperative comorbidities, duration of anesthesia, cell saver use, and volume of allogeneic blood transfused, were investigated. Patients transfused with >840 mL (6 units) were excluded. Propensity scores for receiving transfusion were calculated, with one-to-one matching based on estimated propensity scores to adjust for patients' baseline characteristics. The proportions of complications were compared in patients with and without transfusions. This study was funded by grants from the Ministry of Health, Labour and Welfare, Japan.

RESULTS

Of the 84,650 patients identified, 5,289 patients (6.1%) received transfusions, with 4,436 (5.2%) receiving up to 840 mL. One-to-one propensity score matching resulted in 4,275 pairs with and without transfusion. Patients transfused were at increased risk of SSI (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.4-2.5; p<.001) and urinary tract infection (OR, 2.5; 95% CI, 1.5-4.2; p<.001) than those not transfused.

CONCLUSIONS

Allogeneic blood transfusion after elective lumbar surgery was associated with increased risks of SSI and urinary tract infection.

Allogeneic blood transfusions and postoperative infections after lumbar spine surgery

BACKGROUND CONTEXT

Allogeneic blood transfusions have an immunomodulating effect, and the previous studies in other fields of medicine demonstrated an increased risk of infections after administration of allogeneic blood transfusions.

PURPOSE

Our primary null hypothesis is that exposure to allogeneic blood transfusion in patients undergoing lumbar spine surgery is not associated with postoperative infections after controlling for patient and treatment characteristics. Second, we assessed if there was a dose-response relationship per unit of blood transfused.

STUDY DESIGN/SETTING

This is a retrospective cohort study from a tertiary care spine referral center.

PATIENT SAMPLE

A total of 3,721 patients underwent laminectomy and/or arthrodesis of the lumbar spine.

OUTCOMES MEASURES

Postoperative infections, pneumonia, endocarditis, meningitis, urinary tract infection, central venous line infection, surgical site infection, and sepsis, within 90 days after lumbar spine surgery were included.

METHODS

Multivariable logistic regression analyses were used to assess the relationship of perioperative allogeneic blood transfusion with specific and overall postoperative infections accounting for age, duration of surgery, duration of hospital stay, comorbidity status, preoperative hemoglobin, sex, type of operation, multilevel treatment, operative approach, and year of surgery.

RESULTS

The adjusted odds ratio for exposure to allogeneic blood transfusion from multivariable logistic regression analysis was 2.6 for any postoperative infection (95% confidence interval [CI]: 1.7-3.9, p<.001); 2.2 for urinary tract infections (95% CI: 1.3-3.9, p=.004); 2.3 for pneumonia (95% CI: 0.96-5.3, p=.062); and 2.6 for surgical site infection requiring incision and drainage (95% CI: 1.3-5.3, p=.007). Secondary analyses demonstrated no dose-response relationship between the number of blood units transfused and any of the postoperative infections. Because of the low number of endocarditis (1 case, 0.031%), meningitis (1 case, 0.031%), central venous line infection (1 case, 0.031%), and sepsis (14 cases, 0.43%), we abstained from multivariable analysis.

CONCLUSIONS

Conscious of the limitations of this retrospective study, our data suggest an increased risk of surgical site infection, urinary tract infection, and overall postoperative infections, but not pneumonia, after exposure to allogeneic blood transfusion in patients undergoing lumbar spine surgery. These findings should be taken into account when considering blood transfusion and developing transfusion policies for patients undergoing lumbar spine procedures.

Patient-, procedure-, and hospital-related risk factors of allogeneic and autologous blood transfusion in pediatric spinal fusion surgery in the United States

STUDY DESIGN

Cross-sectional study using data from the Health Care Cost and Utilization Project Kids' Inpatient Database.

OBJECTIVE

Blood loss during spinal fusion surgery may lead to the need for transfusion. Preoperative identification of patient-related, procedure-related, or hospital-related risk factors for blood transfusion would allow for implementation of interventions designed to control excessive bleeding.

SUMMARY OF BACKGROUND DATA

Several studies have analyzed predictors associated with transfusion in spinal fusion. Identified predictors include age, female sex, anemia, comorbidities, number of fusion levels, osteotomy, and greater hospital volume. There have been few studies examining these predictors in children undergoing spinal fusion.

METHODS

Using Kids' Inpatient Database data, univariate and multivariate logistic regression was used to calculate unadjusted and adjusted odds ratios (aOR). P values of less than 0.05 were considered statistically significant.

RESULTS

We identified 9538 pediatric hospitalizations (patients <21 yr) with spinal fusion in 2009. Overall, 25.1% were associated with blood transfusion. The following factors were associated with transfusions: female sex (aOR 1.14, P = 0.023), black race (aOR 1.35, P = 0.005), length of hospital stay (aOR 1.03, P < 0.001), anterior approach/lumbar segment (aOR 2.11, P = 0.011) and posterior approach/lumbar segment (aOR 2.75, P < 0.001) compared with anterior approach/cervical segment, midlength fusion (aOR 1.71, P < 0.001), and long length fusion (aOR 2.85, P < 0.001) compared with short length. Higher transfusion rates were observed in patients with complications of fever and hematoma but not wound infection.

CONCLUSION

This study showed significant patient-, procedure-, and hospital-related predictors of allogeneic and autologous blood transfusion in spinal fusion in the pediatric age group. Higher health care resource utilization of length of stay and additional procedures are directed toward care of this transfused subgroup. Therapies to reduce blood loss and transfusion requirement are necessary for this pediatric population.

LEVEL OF EVIDENCE

4.

Does mechanical filtration of intraoperative cell salvage effectively remove titanium debris generated during instrumented spinal surgery? An in vitro analysis

BACKGROUND CONTEXT

Instrumented fusion of the spine is a surgery commonly performed to stabilize vertebrae causing pain and to correct anatomic deformities. Such surgery can create substantial blood loss. Autotransfusion is a means to limit homologous blood transfusion in this setting. However, a dilemma is created when the high-speed drill used for bone removal comes in contact with implanted titanium spinal hardware. A clinician at this point is forced to decide between two options: to discontinue autotransfusion to avoid the potential transfusion of titanium fragments while risking blood loss and the need for homologous transfusion or to continue autotransfusion while risking transfusion of titanium fragments back into circulation.

PURPOSE

To conclusively identify whether titanium fragments created by a high-speed drill are able to pass through standard autotransfusion microaggregate blood filters.

STUDY DESIGN

A positive and negatively controlled experiment with blinded sample analysis.

OUTCOMES MEASURES

The presence or absence of titanium alloy on a filter with detection by energy-dispersive X-ray spectroscopy (EDX).

METHODS

A mock autotransfusion setup was devised for in vitro filtering. Six investigational and two control experiments were conducted. Titanium fragments generated by a high-speed drill were aspirated with saline and filtered with standard autotransfusion reservoirs and microaggregate blood filters. A final filter with a 1-μm pore size was placed distal to the blood filters. After filtration was complete, this final filter was analyzed using EDX.

RESULTS

The presence of titanium was confirmed by EDX on five of six investigational filters. The positive and negative control filters were analyzed by EDX and tested positive and negative, respectively, for titanium.

CONCLUSIONS

Standard 40 μm reservoir and blood microaggregate filters do not eliminate the smallest fragments of titanium generated by contact between a high-speed drill and a titanium hardware. The mass of titanium able to elude filtration is very small. The impact of transfusing blood contaminated with such a small mass of titanium is not known.

Predictors of allogeneic blood transfusion in spinal fusion for pediatric patients with idiopathic scoliosis in the United States, 2004-2009

STUDY DESIGN

Analysis of population-based National Hospital Discharge Survey data collected for the Nationwide Inpatient Sample.

OBJECTIVE

To examine the predictors of allogeneic blood transfusion (ALBT) in spinal fusion for pediatric patients with idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA

Spinal fusion for pediatric patients with idiopathic scoliosis is associated with major blood loss and often necessitates ALBT.

METHODS

The Nationwide Inpatient Sample was used to identify pediatric patients with idiopathic scoliosis who underwent spinal fusion from 2004 to 2009, using the International Classification of Diseases, Ninth Revision, Clinical Modification codes. Then, patients who received ALBT were identified using the appropriate International Classification of Diseases, Ninth Revision, Clinical Modification code. Patient demographics, surgical variables, and hospital characteristics were retrieved. Multivariate logistic regression analysis was performed to identify the predictors of ALBT in spinal fusion for pediatric patients with idiopathic scoliosis.

RESULTS

The odds ratio (OR) increased with increasing Elixhauser Comorbidity Score (score 1: OR, 1.55; 95% confidence interval [95% CI], 1.23-1.97; score 2: OR, 2.23; 95% CI, 1.69-2.93; score 3: OR, 2.73; 95% CI, 1.6-4.66; score≥4: OR, 4.18; 95% CI, 1.93-9.06). Patients who underwent posterior approach or anterior and posterior approach surgical procedures were more likely to receive ALBT compared with those who underwent anterior approach surgery (posterior: OR, 2.24; 95% CI, 1.22-4.08; anterior and posterior: OR, 3.35; 95% CI, 1.69-6.63). Patients with a spinal fusion of 9 or more levels were more likely to receive ALBT compared with those with a spinal fusion of 4 to 8 levels (OR, 1.39; 95% CI, 1.05-1.85). There was no difference between patients with or without autologous-related blood transfusion (OR, 0.92; 95% CI, 0.59-1.43).

CONCLUSION

This study identified significant predictors of ALBT in spinal fusion for pediatric patients with idiopathic scoliosis. These factors need to be taken into consideration for patient blood management before surgery. In this study, autologous-related blood transfusion could not avoid ALBT.

Predictors of allogeneic blood transfusion in spinal fusion in the United States, 2004-2009

STUDY DESIGN

Retrospective study.

OBJECTIVE

To examine the predictors of allogeneic blood transfusion (ALBT) in spinal fusion.

SUMMARY OF THE BACKGROUND DATA

Spinal fusion is among the most common surgical procedures that necessitate blood transfusion.

METHODS

Using the appropriate International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) codes, patients who underwent spinal fusion from 2004 to 2009 were identified in the Nationwide Inpatient Sample database. These patients were then divided into groups of those who received ALBT and those who did not, using the appropriate ICD-9-CM code. Patient demographics, surgical variables, and hospital characteristics were also retrieved. Multivariate logistic regression analysis was performed to identify the predictors of ALBT in spinal fusion.

RESULTS

Significant predictors of ALBT in spinal fusion included age, female sex, race status, weight loss, anemia, Elixhauser Comorbidity Score, autologous-related blood transfusion, surgical level, surgical approach, revision surgery, number of fused vertebrae, and insurance status. Pediatric and elderly patients were more likely to receive ALBT than middle-aged patients. African American and Hispanic patients were more likely to receive ALBT than Caucasian patients. As the Elixhauser Comorbidity Score increased, the odds ratio increased (score ≥4; odds ratio, 3.07). Thoracolumbar fusion was the strongest predictor among surgery-related variables (odds ratio, 8.56). Private insurance patients were less likely to receive ALBT than Medicare patients.

CONCLUSION

This study identified significant predictors of ALBT in spinal fusion. These factors need to be taken into consideration when developing a patient blood management strategy before surgery. In this study, autologous-related blood transfusion could not avoid ALBT; on the contrary, it was a significant predictor.

LEVEL OF EVIDENCE

3.

RBC transfusion practices among critically ill patients: has evidence changed practice?

OBJECTIVE

Increasing evidence, including publication of the Transfusion Requirements in Critical Care trial in 1999, supports a lower hemoglobin threshold for RBC transfusion in ICU patients. However, little is known regarding the influence of this evidence on clinical practice over time in a large population-based cohort.

DESIGN

Retrospective population-based cohort study.

SETTING

Thirty-five Maryland hospitals.

PATIENTS

Seventy-three thousand three hundred eighty-five nonsurgical adults with an ICU stay greater than 1 day between 1994 and 2007.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The unadjusted odds of patients receiving an RBC transfusion increased from 7.9% during the pre-Transfusion Requirements in Critical Care baseline period (1994-1998) to 14.7% during the post-Transfusion Requirements in Critical Care period (1999-2007). A logistic regression model, including 40 relevant patient and hospital characteristics, compared the annual trend in the adjusted odds of RBC transfusion during the pre- versus post-Transfusion Requirements in Critical Care periods. During the pre-Transfusion Requirements in Critical Care period, the trend in the adjusted odds of RBC transfusion did not differ between hospitals averaging>200 annual ICU discharges and hospitals averaging≤200 annual ICU discharges (odds ratio, 1.07 [95% CI, 1.01-1.13] annually and 1.03 [95% CI, 0.99-1.07] annually, respectively; p=0.401). However, during the post-Transfusion Requirements in Critical Care period, the adjusted odds of RBC transfusion decreased over time in higher ICU volume hospitals (odds ratio, 0.96 [95% CI, 0.93-0.98] annually) but continued to increase in lower ICU volume hospitals (odds ratio, 1.10 [95% CI, 1.08-1.13] annually), p<0.001.

CONCLUSIONS

In this population-based cohort of ICU patients, the unadjusted odds of RBC transfusion increased in both higher and lower ICU volume hospitals both before and after Transfusion Requirements in Critical Care publication. After adjusting for relevant characteristics, the odds continued to increase in lower ICU volume hospitals in the post-Transfusion Requirements in Critical Care period, but it decreased in higher ICU volume hospitals. This suggests that evidence supporting restrictive RBC transfusion thresholds may not be uniformly translated into practice in different hospital settings.

Predictors of blood transfusion in patients undergoing elective surgery for degenerative conditions of the spine

BACKGROUND

The requirement of blood in the surgery of degenerative conditions of lumbar spine is around 10 %. Preoperative autologous blood donation is an effective method that is used in surgeries with an important blood loss. This is an expensive method because of the great number of predonated blood units not used in the postoperative period (around 70 % in our practice).

OBJECTIVE

To know the risk factors associated with transfusion in the postoperative period in patients who undergo surgeries of degenerative conditions of the lumbar spine.

METHODS

We designed a retrospective study of 142 cases of patients operated for degenerative conditions of the lumbar spine (not including simple disk hernia or adult degenerative scoliosis).

RESULTS

Female sex, age >60 years, preoperative ASA score 3 and preoperative hemoglobin ≤136 g/L are the risk factors related to the need of blood transfusion in the postoperative period. After application of a statistical study, female sex and preoperative ASA score 3 were the most important variables to explain transfusional risk. A woman with ASA score 3 has a 61 % foretold probability to be transfused in the postoperative period, while a man with ASA < 3, only 1.1 %. For this reason, application of this method to patients with these risk factors is more cost-effective.

CONCLUSIONS

Females, ASA 3, preoperative hemoglobin ≤136 g/L and age older than 60 years increase the risk to be transfused in the postoperative period for degenerative conditions of the spine.

Drivers of transfusion decision making and quality of the evidence in orthopedic surgery: a systematic review of the literature

Reasons for variation in transfusion practice in orthopedic surgery are not well understood. This systematic review identified and appraised the quality of the literature in this area to assess the impact of factors associated with the use of allogeneic red blood cell (RBC) transfusion in orthopedic procedures. MEDLINE and EMBASE databases were searched for relevant English language publications. Articles containing a range of MeSH and text terms regarding "blood transfusion," "predictors," and "multiple logistic regression" were retrieved. Articles that focused on patients undergoing orthopedic procedures and that met prespecified inclusion criteria were appraised in terms of potential bias and the appropriateness of statistical approach. A total of 3641 citations were retrieved, and 29 met the inclusion criteria for the review. Articles reported on a range of orthopedic procedures including total hip arthroplasty; total knee arthroplasty, total shoulder arthroplasty, and spinal surgery. Most studies were conducted in the United States (n = 12) or Canada (n = 5). Study quality was moderate; 50% or more of the quality criteria were assessed in 15 articles. Particular areas of concern were the lack of prospective studies, lack of clarity in defining the time interval between risk factor assessment and transfusion outcome, and lack of model validation. A narrative synthesis found that 2 factors consistently influenced the use of RBC transfusion-decreased hemoglobin (n = 25) and increased patient age (n = 18). Increased surgical complexity (n = 12), low body weight (n = 9), presence of additional comorbidities (n = 9), and female sex (n = 7) were also important factors. The general quality of the studies in the field is weak. However, low hemoglobin and increasing age were consistently identified as independent risk factors for RBC transfusion in orthopedic practice. Additional or alternative analytical approaches are required to obtain a more comprehensive, holistic understanding of the decision to transfuse RBCs to patients undergoing orthopedic surgery.

Outcomes after spine surgery among racial/ethnic minorities: a meta-analysis of the literature

BACKGROUND CONTEXT

Prior research has identified disparities in access to care, resource utilization, and outcomes in members of racial and ethnic minorities. However, the role that race/ethnicity may play in influencing outcomes after spine surgery has not been previously studied.

PURPOSE

To characterize the effect of race and ethnicity on outcome after spine surgery.

STUDY DESIGN

Systematic literature review and meta-analysis.

PATIENT SAMPLE

Of 11 investigations selected in the initial analysis, four reported results in a fashion that enabled their inclusion in the meta-analysis. These four studies included a total of 128,635 patients.

OUTCOME MEASURES

"Favorable" or "unfavorable" postsurgical outcomes were determined based on parameters described in each included investigation.

METHODS

A systematic literature review was performed to identify all studies documenting outcomes, complications, or mortality after spine surgical procedures. Eligible studies had to include raw data that enabled separate analysis of white and nonwhite patients. Outcome was categorized as "favorable" or "unfavorable" based on scales included in each investigation. The Q-statistic was used to determine heterogeneity, and a meta-analysis was performed to assess the relative risk for unfavorable outcome among nonwhite patients after spine surgery.

RESULTS

Eleven studies met initial selection criteria but only four were eligible for inclusion in the meta-analysis. The meta-analysis included 128,635 patients among whom 12,194 (9.5%) had unfavorable outcomes. Among white patients, 9.4% sustained an unfavorable outcome as compared with 10.4% of nonwhites.

CONCLUSIONS

In light of the small number of studies able to be included in the meta-analysis, no firm conclusions can be drawn regarding the effect of race/ethnicity on outcome after spinal surgery. There is a pressing need for more robust research regarding spine surgical outcomes among different racial and ethnic minority groups.

Association of allogeneic red-blood cell transfusion with surgeon case-volume

BACKGROUND

Surgeon case-volume predicts a variety of patient outcomes. We hypothesize that surgeon case-volume predicts RBC transfusion across different surgical procedures.

METHODS

We performed a cohort study of 372,670 in-patient surgical cases in the 52 non-federal hospitals in Maryland between 2004 and 2005. The main outcome measure was relative risk of receiving a transfusion.

RESULTS

Overall, 13.9% of patients received a transfusion. Patients seen by the highest case-volume surgeons (>161 cases/y) were more likely to receive a transfusion (16% versus 11%, P < 0.01) compared with middle case-volume surgeons (89-161 cases/y). After adjusting for confounders, the highest case-volume patients were still at increased risk of transfusion [relative risk (RR) 1.10, 1.07-1.14]. This result was true across many surgery types.

CONCLUSIONS

Surgeon case-volume is independently associated with the likelihood of RBC transfusion across a broad range of surgical procedures. Future efforts should be directed towards studying and standardization of transfusion practices.

Allogeneic transfusion after predonation of blood for elective spine surgery

The literature suggests preoperative autologous blood donation in total joint arthroplasty is associated with increased overall transfusion rates compared with nondonation and is not cost-effective for all patients. We asked whether the amount of intraoperative blood loss and blood replacement differs between autologous donors and nondonors in elective spine surgery and whether the rates of allogeneic blood transfusions differ between the two groups; we then determined the cost of wasted predonated units. We retrospectively reviewed 676 patients who underwent elective lumbar spine surgery and compared relevant data to that in a matched cohort of 51 patients who predonated blood and 51 patients who received only cell-saver blood and underwent instrumented spinal fusion. Patients who predonated blood had similar blood loss as patients who did not predonate, but they had more blood replacement (1391 cc compared with 410 cc). Patients who predonated blood also had a lower preoperative hemoglobin level and wasted a half unit of blood on average. There was no major difference in allogeneic blood transfusion rates between the two groups. Our data suggest for short, instrumented lumbar fusion surgeries in patients with a normal coagulation profile, preoperative blood donation is not beneficial.

LEVEL OF EVIDENCE

Level II, therapeutic study.

Change in use of allogeneic red blood cell transfusions among surgical patients

BACKGROUND

Although RBC transfusions can be lifesaving, recent evidence suggests that their use is associated with added morbidity and mortality and that a lower transfusion threshold is safe. It is unclear if this new evidence has translated into decreased RBC use among surgical patients. The purpose of this study is to measure the change in use of RBCs during the last decade.

STUDY DESIGN

We performed a cross-sectional cohort study of all patients who underwent inpatient operations in the 52 hospitals in Maryland in 1997 to 1998 and 2004 to 2005. The primary outcomes variable was whether or not the patient received an allogeneic RBC transfusion. We controlled for confounders related to RBC transfusion, including age, gender, race, type of admission, comorbid conditions, and surgeon patient-volume.

RESULTS

Patients receiving RBCs were older (63 versus 52 years), were more likely to be admitted through the emergency department (37% versus 24%) or as a readmission (12% versus 6.9%), had more Romano-Charlson index comorbidities, and had a higher unadjusted mortality (6.5% versus 1.1%). Comparing 1997 to 1998 to 2004 to 2005, RBC use in surgical patients increased (8.9% versus 14%), although unadjusted mortality decreased (2.0% versus 1.5%). Factors associated with higher adjusted relative risk (RR) of transfusion include age older than 65 years (RR = 2.45), unscheduled admissions (emergency department RR = 1.32, readmission RR = 1.62), Romano-Charlson comorbidities (RR = 1.04 to 2.71), third quartile of surgeon volume (RR = 1.10), death (RR = 1.24), and having operations in 2004 to 2005 (RR = 1.42).

CONCLUSIONS

Despite evidence supporting more restrictive use of RBC transfusions, RBC use among surgical patients has increased during the last decade.

Diabetes and perioperative outcomes following cervical fusion in patients with myelopathy

STUDY DESIGN

Database study using the Nationwide Inpatient Sample administrative data from 1988 through 2004.

OBJECTIVE

To examine perioperative morbidity and mortality for patients diagnosed with myelopathy, with and without diabetes mellitus (DM) (and subclassifications) following cervical spinal fusion.

SUMMARY OF BACKGROUND DATA

DM has been associated with worse outcomes in a variety of orthopedic procedures including spinal surgery. Evidence that patients with DM have more complications following cervical fusion, specifically those treated for myelopathy, has been suggested within the literature but has been poorly explored.

METHODS

Data from 37,732 patients within Nationwide Inpatient Sample database (1988-2004) with diagnostic codes specifying the presence of myelopathy and who underwent cervical fusion were included in the analysis. Patients were compared on the basis of the presence of DM, type of DM, and whether DM was controlled or uncontrolled. Bivariate statistical analyses compared postoperative complication rates while multivariate statistics were used to determine likelihood of complications with DM.

RESULTS

Multivariate regression modeling outlined higher likelihoods of complications and hospital discharge variables with DM, particularly if it was diagnosed as uncontrolled disease. Fewer significant discrepancies in complications were noted in comparison of Type I versus Type II DM.

CONCLUSION

This nationally representative study of inpatients in the United States provides evidence that patients with DM who received cervical fusion secondary to myelopathy are associated with greater perioperative complications, nonroutine discharge, and increased total charges. Subanalyses suggest that uncontrolled DM is a significant associative factor in outcome.

Diabetes and early postoperative outcomes following lumbar fusion

STUDY DESIGN

Retrospective cohort study using data from the Nationwide Inpatient Sample administrative data from 1988 through 2003.

OBJECTIVE

To examine perioperative morbidity and mortality for patients with and without diabetes mellitus following lumbar spinal fusion.

SUMMARY OF BACKGROUND DATA

Diabetes has been associated with worse outcomes in a variety of orthopedic procedures including spinal surgery. There is limited evidence that diabetic patients have more complications following lumbar fusion with little published data to support this conclusion.

METHODS

Data from 197,461 patients who underwent lumbar fusion were included. Over 11,000 patients (5.6%) with a postoperative diagnosis of diabetes mellitus were identified. Selected variables were used for comparison of patients with and without diabetes. Bivariate statistical analyses compared postoperative complication rates while multivariate statistics were used to determine likelihood of complications with diabetes.

RESULTS

Bivariate analysis demonstrated that diabetes was significantly associated with postoperative infection, need for transfusion, pneumonia, in-hospital mortality, and nonroutine discharge (P <or= 0.001). Adjusted multivariate regression analyses, however, suggested no difference in mortality although infection, transfusion, and nonroutine discharge continued to be highly significant (P <or= 0.002). Significantly higher inflation adjusted total charges were also present with patients with diabetes as well as increased lengths of stay (P < 0.001).

CONCLUSION

This nationally representative study of inpatients in the United States provides evidence that diabetes is associated with increased risk for postoperative complications, nonroutine discharge, increased total hospital charges, and length of stay following lumbar fusion. Prospective studies to determine causality as well as the potential impact of diabetes control on these variables have not yet been done.

Red blood cell transfusion practices amongst Canadian anesthesiologists: a survey

PURPOSE

To assess red blood cell transfusion practices among Canadian anesthesiologists.

METHODS

A survey depicting three realistic clinical scenarios of elective surgical procedures with different risks of bleeding was administered to all Canadian practicing members (n = 2,100) of the Canadian Anesthesiologists' Society. Respondents were requested to choose hemoglobin thresholds for which they would transfuse red blood cells under various conditions within each scenario.

RESULTS

We obtained a response rate of 47% (719/1,512). Transfusion thresholds differed significantly between baseline scenarios. A threshold above 70 g x L(-1) was chosen by 48% of respondents in the general surgery scenario compared to 56% in the orthopedic surgery scenario and 79% in the vascular surgery scenario (P < 0.001). A history of coronary artery disease was associated with a transfusion threshold >or= 100 g x L(-1) in a significant proportion of respondents ranging from 20% in the orthopedic surgery scenario to 31% in the general surgery scenario and to 49% in the vascular surgery scenario (P < 0.001). Conversely, changing the patient's age from 60 to 20 yr resulted in the adoption of a transfusion threshold <or= 60 g x L(-1) by > 30% of respondents in two scenarios (P < 0.001). The year of respondent graduation was strongly associated with these findings.

CONCLUSION

There was significant variation in transfusion practices among Canadian anesthesiologists. The type of surgical procedure, patient's age and a history of coronary artery disease influenced reported transfusion threshold. Practice variation in specific subgroups would support the need for further research to identify optimal transfusion thresholds.

Cost and utilization of blood transfusion associated with spinal surgeries in the United States

The purpose of this study was to examine factors associated with the utilization and cost of blood transfusion during and post-spinal fusion surgery. A retrospective, observational study of 42,029 inpatients undergoing spinal fusion surgery in United States hospitals participating in the Perspective( Comparative Database for inpatient use was conducted. Descriptive analysis, logistic regression, and ordinary least squares (OLS) regression were used to describe the factors associated with the use and cost of allogeneic blood transfusion (ABT). Hospitalization costs were $18,690 (SD=14,159) per patient, erythropoietin costs were $85.25 (SD=3,691.66) per patient, and topical sealant costs were $414.34 (SD=1,020.06) per patient. Sub-analysis of ABT restricted to users revealed ABT costs ranged from $312.24 (SD=543.35) per patient with whole blood to $2,520 (SD=3,033.49) per patient with fresh frozen plasma. Patients that received hypotensive anesthesia (OR,1.61; 95% CI, 1.47-1.77), a volume expander (OR,1.95; 95% CI, 1.75-2.18), autologous blood (OR, 2.04; 95% CI, 1.71-2.42), or an erythropoietic agent (OR=1.64; 95% CI, 1.27-2.12) had a higher risk of ABT. Patients that received cell salvage had a lower risk of transfusion (OR=0.40; 95% CI, 0.32-0.50). Most blood avoidance techniques have low utilization or do not reduce the burden of transfusion associated with spinal fusion.

Dysphagia after anterior cervical decompression and fusion: prevalence and risk factors from a longitudinal cohort study

STUDY DESIGN

Retrospective analysis of the incidence and prevalence of dysphagia after anterior cervical decompression and fusion (ACDF).

OBJECTIVES

To examine the incidence and prevalence of dysphagia after ACDF, determine possible associated patient and procedural characteristics, and examine dysphagia's impact on long-term health status and function.

SUMMARY OF BACKGROUND DATA

Dysphagia is a common early complaint after ACDF, but the risk factors associated with its development are not understood.

METHODS

Telephone surveys (Cervical Spine Outcomes Questionnaire) and clinical assessments (Oswestry Neck Disability Scale and SF-36) were used to evaluate 454 patients who had undergone ACDF at one of 23 nationwide sites for individual and procedure characteristics that might contribute to dysphagia.

RESULTS

Of the 454 patients, 30% reported dysphagia at the 3-month assessment (incident cases). The incidence of new complaints of dysphagia at each follow-up point was 29.8%, 6.9%, and 6.6% at 3, 6, and 24 months, respectively. Dysphagia persisted at 6 and 24 months in 21.5% and 21.3% of patients, respectively. The risk of dysphagia increased with number of surgical vertebral levels at 3 months: 1 level, 42 of 212 (19.8%); 2 levels, 50 of 150 (33.3%); 3+ levels, 36 of 92 (39.1%). Patients reporting dysphagia at 3 months had a significantly higher self-reported disability and lower physical health status at subsequent assessments.

CONCLUSION

Duration of preexisting pain and the number of vertebral levels involved in the surgical procedure appear to influence the likelihood of dysphagia after ACDF.

What is the evidence for using hemostatic agents in surgery?

The pharmacological methods used to achieve systemic hemostasis have generated much discussion due to concerns of serious adverse effects (e.g., thromboembolic complications) and costs of therapy in addition to efficacy considerations. There are a limited number of well-controlled trials involving pharmacological hemostasis for spine surgery. In the largest double-blinded randomized controlled trial to date involving spine surgery, there was a trend toward reduced homologous transfusion in patients receiving aprotinin, but the only statistically significant result ( p<0.001) was a reduction in autologous red cell donations. The findings of this trial are important, since the investigators used a number of restrictive transfusion strategies (e.g., autologous donation, low hematocrit trigger for transfusion, blood-salvaging procedures with the exception of no cell saver) that were not always employed in earlier trials involving hemostatic agents. Smaller studies involving antifibrinolytic agents other than aprotinin have demonstrated reductions in blood loss and transfusion requirements in patients undergoing spine surgery, although the results were not always statistically significant. A very large randomized trial would be required to address comparative medication- and transfusion-related adverse events; such a trial involving patients undergoing cardiac surgery is currently being performed. Additionally, cost-effectiveness analyses are needed to help define the role of these agents based on the data that is available.

Predeposit autologous donation in spinal surgery: a multicentre study

BACKGROUND

Allogeneic blood transfusions (ABT) are often necessary in elective spine surgery because of perioperative blood loss. Preoperative autologous blood donation (PABD) has emerged as the principal means to avoid or reduce the need for ABT. Consequently, a multicentre study was conducted to determine the yield and efficacy of PABD in spine surgery and the possible role of recombinant human erythropoietin (EPO) in facilitating PABD.

METHODS

We retrospectively reviewed the hospital charts and blood bank records from all consecutive spine surgery patients who were referred for PABD. Data were obtained from two A-category hospital blood banks and one general hospital. Although we collected data from 1994, the analytic study period was from the last quarter of 1995 to December 2003. Fifty-four (7%) out of 763 patients referred for PABD were rejected, and medical records were available for 680 patients who were grouped into spinal fusion (556; 82%) and scoliosis surgery (124;18%). EPO was administered to 120 patients (17.6%). From 1999 to 2003, PABD steadily increased from 60 to 209 patients per year.

RESULTS

Overall, 92% of the patients were able to complete PABD, 71% were transfused, and almost 80% avoided ABT. PABD was more effective in fusions (86%) than in scoliosis (47%). Blood wastage was 38%, ranging from 18% for scoliosis to 42% for fusions. EPO allowed the results in the anaemic patients to be improved.

CONCLUSIONS

Therefore, despite the limitations of this retrospective study, we feel that PABD is an excellent alternative to ABT in spine surgery. However, the effectiveness of PABD may be enhanced if associated with other blood-saving techniques.