Predictors of allogeneic blood transfusion in total hip and knee arthroplasty in the United States, 2000-2009

Racial and Ethnic Disparities in Primary Total Knee Arthroplasty Outcomes: A Systematic Review and Meta-Analysis of Two Decades of Research

Racial disparities in outcomes following total knee arthroplasty (TKA) remain persistent. This systematic review and meta-analysis aims to comprehensively synthesize data between 2000-2020. An electronic search of studies was performed on PubMed, SCOPUS, and the Cochrane Library databases from January 1, 2000, and December 31, 2020. Random effects models were used to report unadjusted and adjusted estimates for a comprehensive list of care outcomes in TKA. 63 studies met PRISMA criteria. Black patients report greater odds of in-hospital mortality (odds ratio [OR]: 1.37, 95% CI: 1.00-1.59 (p = 0.049); adjusted OR [aOR]: 1.34, 95% CI: 1.09-1.64), in-hospital complications (OR: 1.31, 95% CI: 1.27-1.35), 30-day complications (aOR: 1.19, 95% CI: 1.07-1.33), infection (OR: 1.11, 95% CI: 1.07-1.16; aOR: 1.30, 95% CI: 1.16-1.46), bleeding (OR: 1.33, 95% CI: 1.03-1.71; aOR: 1.47, 95% CI: 1.23-1.75), peripheral vascular events (PVE) (aOR: 1.46, 95% CI: 1.11-1.92), length of stay (LOS) (OR: 1.20, 95% CI: 1.08-1.34), extended-LOS (aOR: 1.89, 95% CI: 1.53-2.33), discharge disposition (OR: 1.59, 95% CI: 1.29-1.96; aOR: 1.96, 95% CI: 1.70-2.25), 30-day (OR: 1.20, 95% CI: 1.13-1.27; aOR: 1.17 95% CI: 1.09-1.26) and 90-day (OR: 1.46, 95% CI: 1.17-1.82) readmission compared to White patients. Disparities in bleeding, extended-LOS, discharge disposition, PVE, and 30-day readmission were observed in Asian patients. Hispanic patients experienced disparities in extended LOS and discharge disposition, while Native-American patients had disparities in bleeding outcomes. Persistent racial disparities in TKA outcomes highlight a need for standardized outcome measures and comprehensive data collection across multiple racial groups to ensure greater healthy equity.

Development and Validation of a Machine Learning Algorithm to Predict the Risk of Blood Transfusion after Total Hip Replacement in Patients with Femoral Neck Fractures: A Multicenter Retrospective Cohort Study

OBJECTIVE

Total hip arthroplasty (THA) remains the primary treatment option for femoral neck fractures in elderly patients. This study aims to explore the risk factors associated with allogeneic blood transfusion after surgery and to develop a dynamic prediction model to predict post-operative blood transfusion requirements. This will provide more accurate guidance for perioperative humoral management and rational allocation of medical resources.

METHODS

We retrospectively analyzed data from 829 patients who underwent total hip arthroplasty for femoral neck fractures at three third-class hospitals between January 2017 and August 2023. Patient data from one hospital were used for model development, whereas data from the other two hospitals were used for external validation. Logistic regression analysis was used to screen the characteristic subsets related to blood transfusion. Various machine learning algorithms, including logistic regression, SVA (support vector machine), K-NN (k-nearest neighbors), MLP (multilayer perceptron), naive Bayes, decision tree, random forest, and gradient boosting, were used to process the data and construct prediction models. A 10-fold cross-validation algorithm facilitated the comparison of the predictive performance of the models, resulting in the selection of the best-performing model for the development of an open-source computing program.

RESULTS

BMI (body mass index), surgical duration, IBL (intraoperative blood loss), anticoagulant history, utilization rate of tranexamic acid, Pre-Hb, and Pre-ALB were included in the model as well as independent risk factors. The average area under curve (AUC) values for each model were as follows: logistic regression (0.98); SVA (0.91); k-NN (0.87) MLP, (0.96); naive Bayes (0.97); decision tree (0.87); random forest (0.96); and gradient boosting (0.97). A web calculator based on the best model is available at: (https://nomo99.shinyapps.io/dynnomapp/).

CONCLUSION

Utilizing a computer algorithm, a prediction model with a high discrimination accuracy (AUC > 0.5) was developed. The logistic regression model demonstrated superior differentiation and reliability, thereby successfully passing external validation. The model's strong generalizability and applicability have significant implications for clinicians, aiding in the identification of patients at high risk for postoperative blood transfusion.

Development of machine learning models to predict perioperative blood transfusion in hip surgery

BACKGROUND

Allogeneic Blood transfusion is common in hip surgery but is associated with increased morbidity. Accurate prediction of transfusion risk is necessary for minimizing blood product waste and preoperative decision-making. The study aimed to develop machine learning models for predicting perioperative blood transfusion in hip surgery and identify significant risk factors.

METHODS

Data of patients undergoing hip surgery between January 2013 and October 2021 in the Peking Union Medical College Hospital were collected to train and test predictive models. The primary outcome was perioperative red blood cell (RBC) transfusion within 72 h of surgery. Fourteen machine learning algorithms were established to predict blood transfusion risk incorporating patient demographic characteristics, preoperative laboratory tests, and surgical information. Discrimination, calibration, and decision curve analysis were used to evaluate machine learning models. SHapley Additive exPlanations (SHAP) was performed to interpret models.

RESULTS

In this study, 2431 hip surgeries were included. The Ridge Classifier performed the best with an AUC = 0.85 (95% CI, 0.81 to 0.88) and a Brier score = 0.21. Patient-related risk factors included lower preoperative hemoglobin, American Society of Anesthesiologists (ASA) Physical Status > 2, anemia, lower preoperative fibrinogen, and lower preoperative albumin. Surgery-related risk factors included longer operation time, total hip arthroplasty, and autotransfusion.

CONCLUSIONS

The machine learning model developed in this study achieved high predictive performance using available variables for perioperative blood transfusion in hip surgery. The predictors identified could be helpful for risk stratification, preoperative optimization, and outcomes improvement.

Explainable artificial intelligence for predicting red blood cell transfusion in geriatric patients undergoing hip arthroplasty: Machine learning analysis using national health insurance data

This study uses machine learning and population data to analyze major determinants of blood transfusion among patients with hip arthroplasty. Retrospective cohort data came from Korea National Health Insurance Service claims data for 19,110 patients aged 65 years or more with hip arthroplasty in 2019. The dependent variable was blood transfusion (yes vs no) in 2019 and its 31 predictors were included. Random forest variable importance and Shapley Additive Explanations were used for identifying major predictors and the directions of their associations with blood transfusion. The random forest registered the area under the curve of 73.6%. Based on random forest variable importance, the top-10 predictors were anemia (0.25), tranexamic acid (0.17), age (0.16), socioeconomic status (0.05), spinal anesthesia (0.05), general anesthesia (0.04), sex (female) (0.04), dementia (0.03), iron (0.02), and congestive heart failure (0.02). These predictors were followed by their top-20 counterparts including cardiovascular disease, statin, chronic obstructive pulmonary disease, diabetes mellitus, chronic kidney disease, peripheral vascular disease, liver disease, solid tumor, myocardial infarction and hypertension. In terms of max Shapley Additive Explanations values, these associations were positive, e.g., anemia (0.09), tranexamic acid (0.07), age (0.09), socioeconomic status (0.05), spinal anesthesia (0.05), general anesthesia (0.04), sex (female) (0.02), dementia (0.03), iron (0.04), and congestive heart failure (0.03). For example, the inclusion of anemia, age, tranexamic acid or spinal anesthesia into the random forest will increase the probability of blood transfusion among patients with hip arthroplasty by 9%, 7%, 9% or 5%. Machine learning is an effective prediction model for blood transfusion among patients with hip arthroplasty. The high-risk group with anemia, age and comorbid conditions need to be treated with tranexamic acid, iron and/or other appropriate interventions.

Incidence and predictors of blood transfusions in one-stage bilateral total hip arthroplasty: a single center prospective cohort study

INTRODUCTION

The safety of performing one-stage bilateral total hip arthroplasty (THA) remains controversial among the orthopedic community. The aim of the present study was to determine the incidence and predictors of blood transfusions in one-stage bilateral THA performed in a high-volume single center.

PATIENTS AND METHODS

Patients undergoing one-stage bilateral THA between 2015 and 2017 were included. The following data were collected from the hospital medical records: age, body mass index (BMI), American Society of Anaesthesiologists (ASA) score, smoking habit, comorbidities, preoperative serum creatinine, serum iron, ferritin, C-reactive protein (CRP), and hemoglobin (Hb). The Hb levels at postoperative day 1 and 3 were also collected.

RESULTS

A total of 367 patients with a mean age of 56.1 years (range, 32-79) were included. Forty-eight (13%) patients were transfused with a mean number of 1.6 blood units per patient. In non-transfused patients, the average Hb drop was 3.6 (SD ± 1) g/dL and 4.9 g/dL (SD ± 1.3) at postoperative day 1 and day 3, respectively. The average preoperative Hb level was 14.64 (SD ± 1.21) g/dL. In the univariate logistic regression, the following variables were predictive factors for transfusions: male gender (OR 0.447; P = 0.01), preoperative hemoglobin level (OR 0.622; P = 0.001), preoperative ferritin level (OR 0.995; P = 0.016), BMI (OR 0.837; P = 0.001), cardiopathy (OR 3.534; P = 0.046), preoperative anaemia (OR 10.54; P = 0.011). In the multivariate logistic regression only preoperative hemoglobin level (OR 0.666; P = 0.01), and BMI (OR 0.868; P = 0.007) were statistically significant.

CONCLUSIONS

The incidence of blood transfusions after one-stage bilateral THA is low in non-anemic patients operated on at a high-volume arthroplasty center. The main predictors of blood transfusions are preoperative Hb level and BMI.

Temporal trends, predictors of blood transfusion and in-hospital outcomes among patients with severe burn injury in the United States-A national database-based analysis

BACKGROUND

Severe burn can be accompanied by life-threatening bleeding on some occasions, thus, blood transfusion is often required in these patients during their hospitalization. Therefore, we aimed to examine temporal trends, predictors, and in-hospital outcomes of blood transfusion in these patients in the United States.

METHODS

The National Inpatient Sample was used to identify severe burn patients between January 2010 and September 2017 in the United States. Trends in the utilization of blood transfusion were analyzed using the Cochran-Armitage trend test. Moreover, propensity score matching (PSM) was employed, and then in-hospital outcomes were compared between these two groups in the matched cohort. Multivariable logistic regressions were further used to validate the results of PSM.

RESULTS

Among 27,260 severe burn patients identified during the study period, 2120 patients (7.18%) received blood transfusion. Blood transfusion rates decreased significantly from 9.52% in 2010 to 5.02% in 2017 (p for trend <.001). In the propensity-matched cohort (2120 pairs with and without transfusion), patients transfused were at increased risk of in-hospital mortality (13.3% vs 8.77%, p < .001), overall postoperative complications (88.3% vs 72.59%, p < .001), longer hospital stays (defined as > median hospital stays = 5 d) (73.8% vs 50.6%, p < .001) and increased overall cost (defined as > median overall costs = 30,746) (81.6% vs 57.3%, p < .001). This was also the case for the multivariable analysis.

CONCLUSIONS

Blood transfusion following severe burn injury may be associated with worse clinical outcomes. The utility for blood transfusion in burn patients warrants further prospective exploration.

Utilization of machine learning methods for predicting surgical outcomes after total knee arthroplasty

Background

Predictive models could help clinicians identify risk factors that cause adverse events after total knee arthroplasty (TKA), allowing for appropriate preoperative preventive interventions and allocation of resources.

Methods

The National Inpatient Sample datasets from 2010–2014 were used to build Logistic Regression (LR), Gradient Boosting Method (GBM), Random Forest (RF), and Artificial Neural Network (ANN) predictive models for three clinically relevant outcomes after TKA—disposition at discharge, any post-surgical complications, and blood transfusion. Model performance was evaluated using the Brier scores as calibration measures, and area under the ROC curve (AUC) and F1 scores as discrimination measures.

Results

GBM-based predictive models were observed to have better calibration and discrimination than the other models; thus, indicating comparatively better overall performance. The Brier scores for GBM models predicting the outcomes under investigation ranged from 0.09–0.14, AUCs ranged from 79–87%, and F1-scores ranged from 41–73%. Variable importance analysis for GBM models revealed that admission month, patient location, and patient’s income level were significant predictors for all the outcomes. Additionally, any post-surgical complications and blood transfusions were significantly predicted by deficiency anemias, and discharge disposition by length of stay and age groups. Notably, any post-surgical complications were also significantly predicted by the patient undergoing blood transfusion.

Conclusions

The predictive abilities of the ML models were successfully demonstrated using data from the National Inpatient Sample (NIS), indicating a wide range of clinical applications for obtaining accurate prognoses of complications following orthopedic surgical procedures.

Predicting postoperative transfusion in elective total HIP and knee arthroplasty: Comparison of different machine learning models of a case-control study

BACKGROUND

Total joint arthroplasty (TJA) is a very successful orthopedics procedure but associates with a significantly high transfusion rate.

OBJECTIVE

In this study, we aimed to determine predictors of postoperative blood transfusion in patients undergoing elective hip and knee TJA patients and compare the accuracy of machine learning (ML) algorithms in predicting transfusion risk.

METHODS

We utilized data from 12,642 patients undergoing primary unilateral TJA. Risk factors and demographic information were extracted, and predictive models were developed using seven ML algorithms. The area under the receiver operating characteristic curve was used to measure the predictive accuracy of each algorithm.

RESULTS

The overall transfusion rate was 18.7%. Patient-related risk factors for transfusion included age 65-85 (Odds Ratio (OR): 1.175-1.222), female (OR: 1.246), American Society of Anesthesiologists grade Ⅱ or greater (OR: 1.264-2.758). Surgical factors included operation time (OR: 1.736), drain use (OR: 2.202) as well as intraoperative blood loss (OR: 7.895). Elevated preoperative Hb (OR: 0.615), Hct (OR: 0.800), BMI (≥24 kg/m2) (OR: 0.613-0.731) and tranexamic acid use (OR: 0.375) were associated with decreased risk of postoperative transfusion. The long short-term memory networks (LSTM) and random forest (RF) models achieved the highest predictive accuracy (p < 0.001).

CONCLUSION

The risk factors identified in the current study can provide specific, personalized postoperative transfusion risk assessment for a patient considering lower limb TJA. Furthermore, the predictive accuracies of LSTM and RF algorithms were significantly higher than the others, making them potential tools for future personalized preoperative prediction of risk for postoperative transfusion.

Efficacy and cost-effectiveness of universal pre-operative iron studies in total hip and knee arthroplasty

Background

The prevalence of anaemia in patients planned for total hip and knee arthroplasty is about 20%. Optimising pre-operative haemoglobin levels by iron supplementation has been shown to decrease transfusion rates, complications and associated morbidity. The need for universal screening with iron studies of all elective arthroplasty patients is not clearly defined at present.

Methods

Retrospective review of 2 sequential cohorts of patients undergoing primary hip or knee arthroplasty by a single surgeon at a single centre between January 2013 and December 2017. The first group of patients underwent pre-operative iron studies only if found to be anaemic, with a haemoglobin below 12g/dl. From January 2015, all patients irrespective of the presence of anaemia were screened with a complete iron profile before surgery. Patients with a confirmed iron deficiency were administered with intravenous iron prior to surgery. The 2 cohorts were compared with regard to blood transfusion rate post-operatively and cost efficiency for universal screening with iron studies.

Results

There was a net decrease in the allogenic blood transfusion rate from 4.76 to 2.92% when universal iron studies were introduced but the difference was not statistically significant. Obtaining universal pre-operative iron studies is cost neutral with the price of allogenic blood transfusion in a similar cohort. We also diagnosed 5 patients with occult malignancies.

Conclusions

Universal screening with pre-operative iron studies and iron infusion in elective arthroplasty patients may reduce allogenic blood requirements and is cost neutral. An additional benefit is the potential to diagnose asymptomatic malignancies. Further studies are required to show the true benefit of universal pre-operative iron screening.

Allogeneic Red Blood Cell Transfusion Rate and Risk Factors After Hemiarthroplasty in Elderly Patients With Femoral Neck Fracture

Objective

This study aimed to determine the rate and risk factors of allogeneic red blood cell transfusions (ABT) after hemiarthroplasty (HA) in elderly patients with femoral neck fracture (FNF).

Methods

The subjects of the study were elderly patients (≥65 years old) who were admitted to the geriatric trauma orthopedics ward of Beijing Jishuitan Hospital between March 2018 and June 2019 for HA treatment due to an FNF. The perioperative data were collected retrospectively, and univariate and multivariate stepwise logistic regression analyses were performed to determine the post-operative ABT rate and its risk factors.

Results

There were 445 patients in the study, of whom 177 (39.8%) received ABT after surgery. Multivariate stepwise logistic regression analysis showed that preoperative low hemoglobin (Hb), high intraoperative blood loss (IBL), advanced age, and a low body mass index (BMI) are independent risk factors of ABT after HA in elderly FNF patients.

Conclusion

ABT after HA is a common phenomenon in elderly patients with FNF. Their post-operative ABT needs are related to preoperative low Hb, high IBL, advanced age, and low BMI. Therefore, ABT can be reduced by taking these factors into account. When the same patient had three risk factors (preoperative low hemoglobin, advanced age, and low BMI), the risk of ABT was very high (78.3%). Also, when patients have two risk factors of preoperative low hemoglobin and low BMI, the risk of ABT was also high (80.0%).

Factors for Blood Transfusions Following Hemi Hip Arthroplasty for Patients With Femoral Neck Fracture

Background:

Hemi hip arthroplasty is one treatment option for femoral neck fractures; however, there has been limited evidence on factors associated with blood transfusions following hemi hip arthroplasty. Hence, the aim of this study was to identify the predictors of blood transfusion after hemi hip arthroplasty, which could lead to the establishment of proper guidelines for management protocols.

Materials and Methods:

This study was a retrospective cohort study, conducted in a single center of 323 femoral neck fracture patients having undergone hemi hip arthroplasty. Peri-operative factors and demographic data were extracted from the electronic medical records, from 2007 to 2019. A predictive model was developed by logistic regression (LR), and adjusted by multivariate logistic regression.

Result:

One hundred and twenty-six (39%) patients received blood transfusions. On multivariate analysis, those of a female gender (odds ratio (OR) 2.00, p = 0.037), having a body mass index lower than 18.5 kg/m² (OR 2.40, p = 0.028), lower preoperative hemoglobin levels (OR 0.52, p < 0.001) and given general anesthesia (OR 2.07, p = 0.028) were shown to be significantly associated with a higher risk of requiring a blood transfusion.

Conclusion:

The authors recommend that preparation of blood components coupled with the utilization of blood conserving methods for high risk patients, as studies have stated, in addition to the consideration of spinal anesthesia; if patients have no contraindication, should be implemented.

Does the correction angle affect hidden blood loss in HTO?

Background

High tibial osteotomy (HTO) has a history of nearly 60 years and has been widely used in clinical practice. Biplanar open wedge high tibial osteotomy (BOWHTO), which evolved from HTO, is an important therapy for the knee osteoarthritis. In our previous research, we found that the decrease of hemoglobin levels after high tibial osteotomy ranges from between 17 to 41 g/L, but this is highly inconsistent with the intraoperative bleeding and postoperative drainage observed in clinical practice. The purpose of this study was to investigate the perioperative hidden blood loss (HBL) after biplanar open wedge high tibial osteotomy (BOWHTO), as well as to study the effect of the actual correction angle on blood loss.

Methods

A retrospective analysis was performed on 21 patients who underwent BOWHTO for osteoarthritis of the knee due to proximal tibia deformity. Gross equation was used to calculate the perioperative total blood loss (TBL) and HBL. The actual correction angle was measured by postoperative anteroposterior radiograph. The correlation between HBL and correction angle was determined through correlation analysis.

Results

The TBL was 823.5 ± 348.7 mL and the HBL was 601.6 ± 297.3 mL, total hemoglobin loss was 25.0 ± 10.7 g/L, and the mean HBL/patient’s blood volume (H/P) was 13.19 ± 5.56% for 21 patients. The correlation coefficient of correction angle and H/P is statistically significant (|r| = 0.678, P = 0.001).

Conclusions

The actual total blood loss after BOWHTO was significantly higher than the observed, and the HBL was objective existent after BOWHTO. The proportion of H/P is positively correlated with the correction angle.

Daily Postoperative Complete Blood Counts After Primary Total Joint Arthroplasty May Not Always Be Necessary

As the incidence of primary total hip and knee arthroplasties increases and reimbursement models shift toward a more quality-based model, orthopedic surgeons must focus on maintaining quality while containing costs. With current blood conservation strategies, serial laboratory testing after total joint arthroplasty (TJA) may not always be necessary. This study investigated the need for routine postoperative complete blood counts (CBCs) by determining preoperative and postoperative day 1 hemoglobin values that predict the need for a postoperative blood transfusion. Data were used to estimate potential cost savings. The medical records of all patients who underwent primary unilateral TJA performed by a single surgeon between October 2014 and September 2017 were reviewed. Patient demographic and procedural data were recorded, and statistical and cost analyses were performed. Of 108 TJAs, 9 (8.3%) patients received a blood transfusion during their postoperative inpatient stay. A preoperative hemoglobin value of 12.5 g/dL or less and a postoperative day 1 hemoglobin value of 10 g/dL or less were strong predictors of meeting the threshold transfusion trigger for a postoperative blood transfusion (area under the curve, 0.845 and 0.943, respectively). A 56% cost reduction ($845) could have been achieved by eliminating CBCs performed after postoperative day 1 in patients at low risk for transfusion. Patients with preoperative hemoglobin value levels greater than 12.5 g/dL and postoperative day 1 hemoglobin value levels greater than 10 g/dL may not require routine serial CBC monitoring after primary TJA. The cost savings in a high-volume joint center could be significant. [Orthopedics. 2020; 43(1): e31-e36.].

Higher Rate of Early Revision Following Primary Total Knee Arthroplasty in Patients Under Age 55: A Cautionary Tale

BACKGROUND

There has been an increased number of total knee arthroplasties (TKAs) performed in young and active patients. Although improved materials have decreased the likelihood of early catastrophic wear, concerns remain with the performance and survivorship of TKA implants in this patient population. The purpose this study is to evaluate perioperative complications, patient-reported outcomes, and implant survivorship of TKAs performed in patients under age 55.

METHODS

We retrospectively reviewed 4259 primary TKAs performed over a 4-year period. There were 741 TKAs in patients under age 55. The primary outcome of interest was rate of revision at 30 days, 1, 2, and 5-year time points. Secondary outcomes included postoperative transfusion rate, length of stay, rate of deep vein thrombosis/pulmonary embolism, need for manipulation under anesthesia, readmission and reoperation within 30 days, as well as patient-reported outcomes.

RESULTS

There were 3518 patients over 55 years and 741 patients under 55 years. Overall, 175 patients required revision (4.1%). Patients under 55 years had significantly higher cumulative revision rate at 1 (3.4% vs 1.8%, P < .001), 2 (5.0% vs 2.4%, P < .001), and 5 years (7.3% vs 3.7%, P < .001). Patients under 55 years had a higher rate of early reoperation. Patients over 55 years required more transfusions and suffered a higher rate of early deep vein thrombosis. Patients over 55 years had significantly greater improvements in Patient Reported Outcome Measurement Information System Global 10 Physical scores at 6 months postoperatively compared to patients under 55 years.

CONCLUSIONS

Despite improvements in TKA implants, young and active patients remained at higher risk of early revision compared to older patients. The data should be used to counsel young prospective TKA patients about the early risk of reoperation and non-wear-related complications.

The Effect of Prosthesis Design on Blood Loss in Simultaneous Bilateral Total Knee Arthroplasty: Closed-Box versus Open-Box Prosthesis

Background

Various pre- and perioperative risk factors have been reported in association with blood loss in knee arthroplasty. However, the effect of the uncovered cancellous surface on blood loss in simultaneous bilateral total knee arthroplasty (SBTKA) by different prosthetic designs is not well elucidated. Therefore, this study aimed to compare the blood loss and transfusion rate between different knee prostheses in SBTKA and to identify risk factors that influence blood loss and transfusion after SBTKA.

Methods

Demographic and perioperative data of patients who underwent SBTKA using either a closed-box or an open-box femoral component of posterior-stabilized fixed-bearing (PS FB) knee system were retrospectively reviewed. The calculated blood loss (CBL) and blood transfusion rate were compared by using Student t-test and confirmed with multivariate regression analysis.

Results

There was no significant difference in preoperative parameters between 54 closed-box and 56 open-box PS FB TKAs. The CBL of the closed-box TKA group was 135.23 mL less (95% confidence interval [CI], −215.30 to −55.16; p = 0.001) than that of the open-box TKA group. However, the blood transfusion rates of the closed- and open-box TKA groups were not significantly different (24.1% and 38.5%, p = 0.11). For each additional minute of total operative time, 3.75 mL (95% CI, 1.75 to 5.76; p < 0.001) of blood loss was anticipated. For each additional mg/dL of preoperative hemoglobin, 71% (p < 0.001) reduction of blood transfusion probability was predicted.

Conclusions

The use of closed- and open-box knee prostheses resulted in a significant difference in blood loss in SBTKA. Prolonged operative time also significantly increased CBL. Therefore, strategies to control the bleeding surface and shorten operative duration may be considered if blood loss is of special concern. The preoperative hemoglobin was the only factor that affects the probability of blood transfusion in SBTKA.

Preoperative Blood Management Strategy for Elective Hip and Knee Arthroplasty

To improve quality and outcomes, a preoperative anemia clinic (PAC) was established to screen, evaluate, and manage preoperative anemia. A retrospective review of primary and revision hip and knee arthroplasty patients from August 2013 to September 2017 was conducted. Patients at "high risk" for transfusion were referred to PAC for treatment with iron, erythropoietin, or both based on anemia type. Preoperative anemia clinic referred patients were compared with a 1:3 historic propensity-matched control set of patients to help determine impact of PAC. Forty PAC patients were compared with 120 control patients. Among PAC patients, 26 (63.41%) received iron only, 3 (7.32%) received erythropoietin (EPO) only, and 12 (29.27%) received both. Preoperative hemoglobin significantly increased in the treatment group (median [interquartile range] 10.9 g/dl [10.3-11.2] vs. 12.0 g/dl [11.2-12.7]; p < .001). Four PAC patients (10.00%) received red blood cell transfusions compared with 29 (24.17%) from matched controls (p = .055). In addition, the PAC cohort had higher postoperative nadir hemoglobin levels (mean [SD] 9.7 g/dl [1.31] vs. 8.7 g/dl [1.25]; p < .001). High-risk patients appropriately treated with iron and/or EPO before surgery demonstrate a significant increase in preoperative hemoglobin, trend toward decrease perioperative transfusion, and increased hemoglobin levels postoperatively compared with matched controls.

Blood loss reduction: effect of different knee prosthesis designs and use of tranexamic acid-a randomized controlled trial

PURPOSE

In regard to blood loss in total knee arthroplasty (TKA), the effect of either knee prosthesis designs or bone preparation is still unclear. While the benefit of using tranexamic acid (TXA) is well demonstrated, our study aims to determine the effect of different knee prosthesis designs uses and efficacy of blood loss reduction by different routes of TXA administration.

METHODS

The 228 patients undergone primary TKA were randomized to determine between open-box and closed-box prosthesis. Among each group, a second randomization was applied to categorize the patients into (1) no use of TXA (No-TXA), (2) intra-articular TXA use (IA-TXA) and (3) intravenous TXA use (IV-TXA). The calculated blood loss (CBL), drain volume (DV) and an average number of units of blood transfused (ANUBT) were blindly evaluated.

RESULTS

The open-box TKA had 85.60 and 63.29 ml (p = 0.02 and p < 0.01) more CBL and DV compared to closed-box TKA. The IA-TXA and IV-TXA significantly reduced CBL by 190.75 and 162.01 ml (p < 0.01 and p < 0.01) and reduced DV by 129.07 and 61.04 ml (p < 0.01 and p = 0.01), respectively, when compared to No-TXA. Patients who received IA and IV-TXA had ANUBT of 0.21 and 0.23 unit, which was significantly lower than 0.42 unit of No-TXA group (p = 0.03).

CONCLUSIONS

Use of the different prosthesis designs could significantly affect CBL and DV following TKA. However, the use of either design resulted in a comparable ANUBT. Regardless of prosthetic type, either IA- or IV-TXA could significantly reduce the CBL and ANUBT when compared to No-TXA.

Oral vs intravenous tranexamic acid in total-knee arthroplasty and total hip arthroplasty: A systematic review and meta-analysis

BACKGROUND

This study aimed to compare the efficacy and safety of oral tranexamic acid (TXA) with intravenous (IV) TXA in reducing perioperative blood loss in total-knee arthroplasty (TKA) and total-hip arthroplasty (THA).

METHODS

PubMed, Web of Science, Embase, and Cochrane Library were fully searched for relevant studies. Studies comparing the efficacy and safety of oral TXA with IV TXA in TKA and THA were included in this research. Odds ratio (OR) or risk difference (RD) was applied to compare dichotomous variables, while mean difference (MD) was used to compare continues variables.

RESULTS

A total of 7 studies (5 randomized controlled trials and 2 retrospective studies) were included into this study. As for patients undergoing TKA or THA, there were no obvious differences between oral TXA group and IV TXA group in hemoglobin (Hb) drop (MD = 0.06, 95% confidence interval [CI] = -0.01 to 0.13, P = .09), transfusion rate (OR = 0.78, 95% CI = 0.54-1.13, P = .19), total blood loss (MD = 16.31, 95% CI = -69.85 to 102.46, P = .71), total Hb loss (MD = 5.18, 95% CI = -12.65 to 23.02, P = .57), length of hospital stay (MD = -0.06, 95% CI = -0.30 to 0.18, P = .63), drain out (MD = 21.04, 95% CI = -15.81 to 57.88, P = .26), incidence of deep vein deep vein thrombosis (RD = 0.00, 95% CI = -0.01 to 0.01, P = .82) or pulmonary embolism (RD = 0.00, 95% CI = -0.01 to 0.01, P = .91). The sample size of this study was small and several included studies were with relatively low quality.

CONCLUSION

Oral TXA is equivalent to IV TXA in reducing perioperative blood loss and should be recommended in TKA and THA. More high-quality studies are needed to elucidate this issue.

Intra-Articular Tranexamic Acid Mitigates Blood Loss and Morphine Use After Total Knee Arthroplasty. A Randomized Controlled Trial

BACKGROUND

Tranexamic acid (TXA) has been widely used in total knee arthroplasty (TKA) for blood loss reduction. Given limited evidence on potential relationship between the TXA and improvement of pain control and functional outcome after TKA, this study aimed at comparing the blood loss, pain scores, morphine consumption, and knee flexion across the TXA administration routes.

METHODS

The 228 primary TKA were randomized into no TXA use (No-TXA), intra-articular TXA (15 mg/kg) use (IA-TXA), and intravenous TXA (10 mg/kg) use (IV-TXA). A multivariate regression analysis was used for comparing perioperative blood loss (PBL), drain output, average number of units of blood transfused (ANUBT), visual analogue scales (VAS) for pain, amount of morphine consumption, and knee flexion angle.

RESULTS

The IA-TXA and IV-TXA group had 193.26 (P < .01) and 160.30 mL (P < .01) less PBL than No-TXA, respectively. No-TXA significantly required higher ANUBT than IA-TXA and IV-TXA (P = .03). The IA-TXA group had lower VAS at 6 (P = .04), 12 (P = .03), and 24 hours (P = .02) postoperative when compared to No-TXA, while IV-TXA had no effect. The IA-TXA required 18.26 mg less total morphine at 48 hours than No-TXA (P = .02), whereas IV-TXA used insignificantly (5.31 mg; P = .31) less total morphine at 48 hours than No-TXA. Both TXA routes tended to improve knee flexion, but not statistically significant.

CONCLUSION

Both IA-TXA and IV-TXA could significantly reduce PBL and ANUBT. The IA-TXA could significantly mitigate VAS and morphine use after TKA. Hence, IA-TXA could minimize blood loss and may be considered as an adjunct to pain control following TKA.

Factors associated with red blood cell, platelet, and plasma transfusions among inpatient hospitalizations: a nationally representative study in the United States

BACKGROUND

Demographic and hospital-level factors associated with red blood cell (RBC), plasma, and platelet transfusions in hospitalized patients across the U.S. are not well characterized.

METHODS

We conducted a retrospective analysis of the National Inpatient Sample (2014). The unit of analysis was a hospitalization; sampling weights were applied to generate nationally-representative estimates. The primary outcome was having ≥ 1 RBC transfusion procedure; plasma and platelet transfusions were similarly assessed as secondary outcomes. For each component, factors associated with transfusion were measured using adjusted prevalence ratios (adjPR) and 95% confidence intervals (95% CI) estimated by multivariable Poisson regression.

RESULTS

The prevalence of RBC, plasma, and platelet transfusion was 5.8%, 0.9%, and 0.7%, respectively. RBC transfusions were associated with older age (≥ 65 vs. < 18 years; adjPR = 1.80; 95% CI = 1.66-1.96), female sex (adjPR = 1.13; 95% CI = 1.12-1.14), minority race/ethnic status, and hospitalizations in rural hospitals compared to urban teaching hospitals. Prevalence of RBC transfusion was lower among hospitalizations in the Midwest compared to the Northeast (adjPR = 0.73; 95% CI = 0.67-0.80). All components were more likely to be transfused in patients with a primary hematologic diagnosis, patients with a higher number of total diagnoses, patients who experienced a higher number of other procedures, and patients who eventually died in the hospital. In contrast to RBC transfusions, prevalence of platelet transfusion was greater in urban teaching hospitals (vs. rural; adjPR = 1.71; 95% CI = 1.49-1.98) and lower in blacks (vs. whites; adjPR = 0.80; 95% CI = 0.76-0.85).

CONCLUSIONS

Nationally, there is heterogeneity in factors associated with transfusion between each blood component, including by hospital type and location. This variability presents patient blood management programs with potential opportunities to reduce transfusions.

Analysis of a large data set to identify predictors of blood transfusion in primary total hip and knee arthroplasty

BACKGROUND

The aim of this study was to identify the predictors of need for allogenic blood transfusion (ALBT) in primary lower limb total joint arthroplasty (TJA).

STUDY DESIGN AND METHODS

This study utilized a large dataset of 15,187 patients undergoing primary unilateral TJA. Risk factors and demographic information were extracted from the electronic health record. A predictive model was developed by both a random forest (RF) algorithm and logistic regression (LR). The area under the receiver operating characteristic curve (AUC-ROC) was used to compare the accuracy of the two methods.

RESULTS

The rate of ALBT was 18.9% in total. Patient-related factors associated with higher risk of an ALBT included female sex, American Society of Anesthesiologists (ASA) II, ASA III, and ASA IV. Surgery-related risk factors for ALBT were operative time, drain use, and amount of intraoperative blood loss. Higher preoperative hemoglobin and tranexamic acid use were associated with decreased risk for ALBT. The RF model had a better predictive accuracy (area under the curve [AUC] 0.84) than the LR model (AUC, 0.77; p < 0.001).

CONCLUSION

The risk factors identified in the current study can provide specific, personalized perioperative ALBT risk assessment for a patient considering lower limb TJA. Furthermore, the predictive accuracy of the RF algorithm was significantly higher than that of LR, making it a potential tool for future personalized preoperative prediction of risk for perioperative ALBT.

Decline in allogeneic blood transfusion usage in total hip arthroplasty patients: National Inpatient Sample 2009 to 2013

INTRODUCTION

Although total hip arthroplasty (THA) is an effective treatment for end-stage arthritis, it is also associated with substantial blood loss that may require allogeneic blood transfusion. However, these transfusions may increase the risk of certain complications. The purpose of our study is to evaluate: (i) the incidence/trends of allogeneic blood transfusion; (ii) the associated risk factors and adverse events; and (iii) the discharge disposition, length of stay (LOS), and costs for these patients between 2009 and 2013.

METHODS

The National Inpatient Sample database was used to identify 1,542,366 primary THAs performed between 2009 and 2013. Patients were stratified based on demographics, economic data, hospital characteristics, comorbidities, and whether or not allogeneic transfusion was received. Logistic regression was performed to evaluate the risk factors for transfusion and postoperative complications.

RESULTS

From 2009 to 2013, allogeneic transfusions were used in 16.9% of primary THAs, with a declining annual incidence. Except for obesity, all comorbidities were associated with increased likelihood of receiving a transfusion. Allogeneic transfusion patients were more likely to experience surgical site infections or pulmonary complications (p<0.001 for all). These patients were more likely to be discharged to a short-term care facility (p<0.001). Additionally, they had a greater mean LOS (p<0.001) and higher median hospital costs and charges when compared to their non-transfused counterparts.

CONCLUSIONS

While the observed decline in allogeneic transfusion usage is encouraging, further efforts should focus on preoperative patient optimisation. Given the projected increase in demand for primary THAs, orthopaedic surgeons must be familiar with safe and effective blood conservation protocols.

Are Allogeneic Transfusions Decreasing in Total Knee Arthroplasty Patients? National Inpatient Sample 2009-2013

BACKGROUND

Allogeneic transfusions are commonly used for substantial blood loss in total knee arthroplasty (TKA), but have been associated with adverse effects and increased costs. The purpose of this study is to provide a detailed description of (1) trends of allogeneic blood transfusion; (2) risk factors and adverse events; and (3) discharge disposition, length-of-stay (LOS), and cost/charge analysis for primary TKA patients who received an allogeneic blood transfusion from 2009-2013.

METHODS

A cohort of 3,217,056 primary TKA patients was identified from the National Inpatient Sample database from 2009-2013. Demographic, clinical, economic, and discharge data were analyzed for patients who received allogeneic blood products, and for those who did not receive any type of blood transfusion. Other parameters analyzed include risk factors, adverse events, discharge disposition, and costs/charges.

RESULTS

There was a significant decline in use of allogeneic transfusion from 2009-2013 incidence (13.9%-7.3%; P < .001). All comorbidities examined were associated with significantly increased risk of receiving allogeneic transfusion with exception of patients with AIDS, metastatic cancer, and peptic ulcer disease. Allogeneic transfusion was associated with worse outcomes during hospitalization. Patients also had a greater likelihood of discharge to short-term care, greater LOS, and greater median costs/charges. Among TKA patients who received an allogeneic transfusion, costs varied based on hospital ownership and characteristics, primary-payer, region, and bed-size.

CONCLUSION

Given the poor outcomes and higher costs associated with allogeneic transfusions, efforts must be undertaken to minimize this risky practice. With the projected increase in demand for TKAs, orthopedists must understand effective blood management strategies.

Influence of synovectomy on blood loss and need for transfusion in standard total knee replacement

BACKGROUND

Synovial proliferation is a rather frequent intraoperative finding during the surgery of a total knee replacement. The aim of this study is to asses whether the standard procedure of a synovectomy results in changes in blood loss and in the need for transfusion in the immediate postoperative time after the total knee replacement.

METHODS

A prospective cohort study was performed with 120 patients undergoing total knee replacement (60 with synovectomy and 60 without it). Data on gender, age, and hemoglobin concentration prior to and after surgery were obtained. A bivariate and multivariate logistic regression analysis was performed.

RESULTS

The male gender as a protective factor [RR 0.25 (0.06-1.01)] and the low preoperative hemoglobin as a risk factor [RR 6.22 (2.48-15.58)] were significant in bivariate analysis. However, only the presence of low preoperative hemoglobin was shown to have an independent risk factor for the need for transfusion [RR 8.55 (2.77-26.45)].

CONCLUSION

The practice of synovectomy showed no difference either in blood loss or in the number of transfusions. The findings of this study indicate that the practice of a synovectomy in a standard total knee replacement does not generate any benefit or prejudice as to the blood factor of the total knee arthroplasty.

Risk Factors for Reaching the Post-Operative Transfusion Trigger in a Community Primary Total Knee Arthroplasty Population

BACKGROUND

Little data exist to evaluate an individual's pre-operative risk of blood transfusion following total knee arthroplasty (TKA). Our aim is to identify the risk factors associated with reaching the transfusion trigger of Hb <8 g/dL (TT8) following surgery and how perioperative tranexamic acid (TXA) affects that outcome.

METHODS

Using a retrospective cohort study design, routine, unilateral TKAs performed between 2011 and 2013 in 19 hospitals were reviewed. Patients hospitalized ≤1 day or ≥4 days were excluded. Demographic data, clinical characteristics, and potential confounders were included in statistical models. Data were abstracted from electronic clinical and utilization databases. The main outcome was the risk of reaching the TT8. The primary exposure was use of single dose intravenous TXA. Logistic regression was used to model the adjusted association between TXA usage and post-operative risk of reaching TT8.

RESULTS

A total of 10,518 TKAs met criteria; 2566 (24.3%) received TXA (+TXA). The proportion that reached the TT8 was 2.1% for + TXA and 5.3% for -TXA (P < .0001). Pre-operative Hb levels were associated with increasing odds of reaching the TT8. Increasing age was weakly associated with this outcome. The odds of reaching the TT8 were lower for patients who had received TXA, had increasing body mass index, and surgical duration in the third quartile.

CONCLUSION

Not receiving TXA within 24 hours of TKA and pre-operative Hb levels <13 g/dL were independently associated with the odds of reaching the post-operative TT8 following a primary TKA.

What Should Define Preoperative Anemia in Primary THA?

BACKGROUND

The use of tranexamic acid (TXA) in THA decreases the risk of transfusion after surgery. However, nearly 10% of patients still undergo a transfusion, which has been independently associated with an increased risk of complications. Preoperative anemia has been proven to be a strong predictor of transfusion after THA, but the ideal "cutoff" values in today's population that maximize sensitivity and specificity to predict transfusion have yet to be established.

QUESTIONS/PURPOSES

(1) Which preoperative factors are associated with postoperative transfusion in the setting of TXA use? (2) If preoperative hemoglobin (Hgb) remains associated with transfusion, what are the best-supported preoperative Hgb cutoff values associated with increased transfusion after THA?

METHODS

A retrospective chart analysis was performed from January 1, 2013, to January 1, 2015, on 558 primary THAs that met prespecified inclusion criteria. A multivariable logistic regression analysis model was used to identify independent factors associated with transfusion. Area under the receiver-operator curve (AUC) was used to determine the best-supported preoperative Hgb cut point across all participants, as well as adjusted by sex and TXA use. Overall, 60 patients with a blood transfusion were included and compared with 498 control subjects (11% risk of transfusion).

RESULTS

After controlling for potential confounding variables such as age, sex, American Society of Anesthesiologist score, intravenous TXA (IV TXA) use, and preoperative Hgb, we found that patients with lower preoperative Hgb (g/dL per 1-unit decrease, odds ratio [OR], 2.6; 95% CI, 2.0-3.5; p < 0.001), female sex (vs male, OR, 4.2; 95% CI, 1.7-10.3; p = 0.002), and those unable to receive IV TXA (topical TXA/no TXA, OR, 13.5; 95% CI, 6.3-28.6; p < 0.001) were more likely to receive a transfusion. Of these, preoperative Hgb was found to be the variable most highly associated with transfusion (AUC, 0.876). A preoperative Hgb cutoff value of 12.6 g/dL maximized the AUC (0.876) for predicting transfusion across all patients unadjusted for baseline characteristics (sensitivity = 83, specificity = 84) with values of 12.5 g/dL (sensitivity = 85, specificity = 77) and 13.5 g/dL (sensitivity = 92, specificity = 77) for women and men, respectively.

CONCLUSIONS

The 1968 WHO definitions of anemia (preoperative Hgb < 13 g/dL for men and < 12 g/dL for women) used currently may underestimate patients at risk of transfusion after THA today. Further studies are needed to see if blood conservation referral decreases the risk of transfusion with preoperative treatment of anemia.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Assessing the Accuracy of Reporting of Maternal Red Blood Cell Transfusion at Birth Reported in Routinely Collected Hospital Data

Introduction Hospital administrative data collections have been used to describe transfusion practice, particularly in relation to the maternity population. Knowledge of the accuracy of this data is important in order to interpret the results of such studies. The aim of this study was to compare the accuracy of reporting of red cell transfusion around childbirth within hospital data with data submitted by hospital blood banks. Methods Linked hospital and birth data from New South Wales, Australia, between June 2006 and December 2010 were used to identify blood transfusions occurring at delivery. This reporting was compared with the gold standard of blood pack level information submitted by hospital blood banks, and sensitivity, specificity, and positive and negative predictive values calculated. Reporting related to quantity and timing of transfusion were also considered. Results Data were available for 235,796 births, with blood bank data identifying that 2.0 % of received a blood transfusion. Overall the sensitivity of hospital data for identifying transfusion was 84.8 % (95 % CI 83.7 %, 85.8 %) with specificity 99.9 % (99.9 %, 99.9 %). Sensitivity was better for births involving a postpartum haemorrhage [Sn 90.9 % (89.9 %, 91.9 %)], and poorer for births in regional hospitals [Sn 78.8 % (76.0 %, 81.5 %)]. Almost all (96 %) transfusions of 10 or more units were identified in hospital data, and there was no difference in reporting depending on whether the transfusion was on the baby's date of birth or not. Discussion The reliability of hospital reporting of transfusion in maternity patients is high, however with some underreporting of cases.

Predicting Perioperative Transfusion in Elective Hip and Knee Arthroplasty: A Validated Predictive Model

BACKGROUND

Preoperative anemia is a significant predictor of perioperative erythrocyte transfusion in elective arthroplasty patients. However, interactions with other patient and procedure characteristics predicting transfusion requirements have not been well studied.

METHODS

Patients undergoing elective primary total hip arthroplasty or total knee arthroplasty at a tertiary hospital in Adelaide, South Australia, Australia, from January 2010 to June 2014 were used to identify preoperative predictors of perioperative transfusion. A logistic regression model was developed and externally validated with an independent data set from three other hospitals in Adelaide.

RESULTS

Altogether, 737 adult patients in the derivation group and 653 patients in the validation group were included. Binary logistic regression modeling identified preoperative hemoglobin (odds ratio, 0.51; 95% CI, 0.43 to 0.59; P < 0.001 for each 1 g/dl increase), total hip arthroplasty (odds ratio, 3.56; 95% CI, 2.39 to 5.30; P < 0.001), and females 65 yr of age and older (odds ratio, 3.37; 95% CI, 1.88 to 6.04; P = 0.01) as predictors of transfusion in the derivation cohort.

CONCLUSIONS

Using a combination of patient-specific preoperative variables, this validated model can predict transfusion in patients undergoing elective hip and knee arthroplasty. The model may also help to identify patients whose need for transfusion may be decreased through preoperative hemoglobin optimization.

Predictors of haematocrit in lumbar fusion for lumbar disc herniation: a surgical assessment

BACKGROUND

Low haematocrit (Hct) is associated with a higher rate of post-operative complications, increased mortality, and additional medical costs following cardiac surgery. Predictors of post-operative Hct in lumbar fusion are unclear and may be beneficial in avoiding adverse surgical outcomes.

METHODS

A total of 704 lumbar disc herniation patients (385 males, 319 females) who underwent primary lumbar fusion surgery were reviewed in this retrospective study.

RESULTS

In the 687 patients who met the selection criteria, the pre-operative Hct was 41.23 ± 4.57%, the post-operative Hct was 32.61 ± 4.52%, the peri-operative Hct decline was 8.62 ± 4.07%, the estimated intra-operative blood loss was 586.76 ± 346.62 mL, and the post-operative drainage was 489.33 ± 274.32 mL. Pre-operative Hct, estimated blood volume, estimated intra-operative blood loss, post-operative drainage, allogeneic blood transfusion, and age showed significant correlations with post-operative Hct, and all factors were involved in the final multiple regression model. Patients who received intensive care had lower post-operative Hct values, and the length of post-operative hospital stay was negatively correlated with post-operative Hct.

CONCLUSIONS

Dangerously low post-operative Hct is related to the length of ICU stay and post-operative hospital stay. Age, pre-operative Hct, intra-operative blood loss, post-operative drainage, and units of allogeneic blood transfusion are significant predictors of post-operative Hct and Hct decline. Hct variations during the operation make the calculation of total blood loss difficult.

Predicting Factors for Allogeneic Blood Transfusion and Excessive Postoperative Blood Loss after Single Low-Dosage Intra-Articular Tranexamic Acid Application in Total Knee Replacement

Background. Recently, intra-articular tranexamic acid (IA-TXA) application has become a popular method for perioperative blood loss (PBL) reduction in total knee replacement (TKR). Nevertheless, through our knowledge, no previous studies had shown the correlation perioperative factors and the risk of excessive PBL or need of blood transfusion (BT) after IA-TXA. Materials and Methods. A retrospective study was conducted in patients underwent 299 primary TKRs, using IA-TXA, during 2-year period (2013-2014). Patient's characteristic and perioperative data were reviewed and collected. PBL was measured as total hemoglobin loss (THL), estimated total blood loss (ETBL), and drainage volume per kg (DV/kg). Excessive PBL was defined as PBL that exceeded 90th percentile. Results. From multivariate analysis, low preoperative hemoglobin (Hb) level and body mass index (BMI) were the significant predictors of postoperative BT (p < 0.0001 and 0.003, resp.). Excessive THL significant associated with preoperative Hb (p < 0.0001). Excessive ETBL significantly associated with preoperative Hb, height, preoperative range-of-motion, and creatinine clearance (p < 0.05 all). Low BMI and large prosthesis size were the significant predictors of excessive DV/kg (p = 0.0001 and 0.002, resp.). Conclusions. Low preoperative Hb and BMI were the significant risks of postoperative transfusion after TKR with IA-TXA. Moreover, multiple perioperative factors could result in higher PBL.

Preoperative haemoglobin cut-off values for the prediction of post-operative transfusion in total knee arthroplasty

PURPOSE

The purpose of this study is to determine preoperative haemoglobin cut-off values that could accurately predict post-operative transfusion outcome in patients undergoing primary unilateral total knee arthroplasty (TKA). This will allow surgeons to provide selective preoperative type and screen to only patients at high risk of transfusion.

METHODS

A total of 1457 patients diagnosed with osteoarthritis and underwent primary unilateral TKA between January 2012 and December 2014 were retrospectively reviewed. Logistic regression analyses were applied to identify factors that could predict transfusion outcome.

RESULTS

A total of 37 patients (2.5 %) were transfused postoperatively. Univariate analysis revealed preoperative haemoglobin (p < 0.001), age (p < 0.001), preoperative haematocrit (p < 0.001), and preoperative creatinine (p < 0.001) to be significant predictors. In the multivariate analysis with patients dichotomised at 70 years of age, preoperative haemoglobin remained significant with adjusted odds ratio of 0.33. Receiver operating characteristic curve identified the preoperative haemoglobin cut-off values to be 12.4 g/dL (AUC = 0.86, sensitivity = 87.5 %, specificity = 77.2 %) and 12.1 g/dL (AUC = 0.85, sensitivity = 69.2 %, specificity = 87.1 %) for age above and below 70, respectively.

CONCLUSIONS

The authors recommend preoperative haemoglobin cut-off values of 12.4 g/dL for age above 70 and 12.1 g/dL for age below 70 to be used to predict post-operative transfusion requirements in TKA. To maximise the utilisation of blood resources, the authors recommend that only patients with haemoglobin level below the cut-off should receive routine preoperative type and screen before TKA.

LEVEL OF EVIDENCE

IV.

A protocol avoiding allogeneic transfusion in joint arthroplasties

INTRODUCTION

Arthroplasties of hip and knee are associated with blood loss, which may lead to adverse patient outcome. Performing arthroplasties in Jehovah's Witness patients who do not accept transfusion has been a matter of concern. We developed a protocol, which avoids transfusion in arthroplasties of Jehovah's Witness patients, and evaluated the feasibility and safety of the protocol.

MATERIALS AND METHODS

The target of preoperative hemoglobin was more than 10 g/dL. When preoperative hemoglobin was lower than 10 g/dL, 4000 U erythropoietin (3 times a week) and 100 mg iron supplement (every day) were administered until the hemoglobin reached 10 g/dL. When the preoperative hemoglobin was higher than 10 g/dL, 4000 U erythropoietin and 100 mg iron supplement were administered once, before operation. During the operation, cell saver was used. Postoperatively, erythropoietin and iron supplements were administered until the hemoglobin reached 10 g/dL, similar to the preoperative protocol. We evaluated the feasibility of our protocol, perioperative complications and hematologic changes.

RESULTS

From 2002 to 2014, 186 Witness patients visited our department. In 179 patients (96.2 %), 77 total knee arthroplasties, 69 bipolar hemiarthroplasties and 33 total hip arthroplasties were performed. The mean hemoglobin level was 12.3 g/dL preoperatively, 9.4 g/dL on postoperative day 3 and 10.3 g/dL on postoperative day 7. One patient died immediately after the arthroplasty and the remaining 178 patients survived.

CONCLUSIONS

Total joint arthroplasty could be done without transfusion using this protocol in most of our patients. The rates of infection and mortality were similar with known infection and mortality rates of arthroplasties. In patients who do not want allogeneic transfusions, our protocol is a safe alternative to perform joint arthroplasties.

Is there a need for routine post-operative hemoglobin level estimation in total knee arthroplasty with tranexamic acid use?

BACKGROUND

Total knee arthroplasty (TKA) can result in significant blood loss, leading to a need for blood transfusion. The major indication of transfusion is post-operative hemoglobin (Hb) levels in association with symptomatic anemia. The aim of this study was to determine the possibility of eliminating routine post-operative Hb tests in patients undergoing TKA with intra-articular tranexamic acid (TXA) use based on the predictability of pre-operative factors.

METHODS

We conducted a retrospective analysis of 487 patients who underwent TKA with intra-articular TXA use. Statistical analysis was done to predict the transfusion risk based on multiple pre-operative parameters.

RESULTS

Post-operative blood transfusions were required in 2.5% of all patients. Pre-operative-Hb was the only significant predictor of post-operative transfusion (p<0.0001). Age, sex, weight, height and body mass index (BMI) were not related to post-operative transfusion risk. Transfusions were needed in 4.2% of patients with pre-operative Hb levels <14 g/dl. No patient with a pre-operative Hb >14 g/dl required a transfusion (p<0.0001).

CONCLUSIONS

Pre-operative Hb is a strong predictor of post-operative blood transfusion risk. Patients who receive TXA in TKA, with a pre-operative Hb >14 g/dl do not require routine post-operative Hb evaluation.

LEVEL OF EVIDENCE

IV.

Perioperative blood ordering optimization process using information from an anesthesia information management system

BACKGROUND

As part of ongoing perioperative surgical home implantation process, we applied a previously published algorithm for creation of a maximum surgical blood order schedule (MSBOS) to our operating rooms. We hypothesized that using the MSBOS we could show a reduction in unnecessary preoperative blood testing and associated costs.

STUDY DESIGN AND METHODS

Data regarding all surgical cases done at UC Irvine Health's operating rooms from January 1, 2011, to January 1, 2014 were extracted from the anesthesia information management systems (AIMS). After the data were organized into surgical specialties and operative sites, blood order recommendations were generated based on five specific case characteristics of the group. Next, we assessed current ordering practices in comparison to actual blood utilization to identify potential areas of wastage and performed a cost analysis comparing the annual hospital costs from preoperative blood orders if the blood order schedule were to be followed to historical practices.

RESULTS

Of the 19,138 patients who were categorized by the MSBOS as needing no blood sample, 2694 (14.0%) had a type and screen (T/S) ordered and 1116 (5.8%) had a type and crossmatch ordered. Of the 6073 procedures where MSBOS recommended only a T/S, 2355 (38.8%) had blood crossmatched. The cost analysis demonstrated an annual reduction in actual hospital costs of $57,335 with the MSBOS compared to historical blood ordering practices.

CONCLUSION

We showed that the algorithm for development of a multispecialty blood order schedule is transferable and yielded reductions in preoperative blood product screening at our institution.

Effectiveness of preoperative autologous blood donation for protection against allogeneic blood exposure in adult spinal deformity surgeries: a propensity-matched cohort analysis

OBJECTIVE

The goal of this study was to examine the effectiveness of preoperative autologous blood donation (PABD) in adult spinal deformity (ASD) surgery.

METHODS

Patients undergoing single-stay ASD reconstructions were identified in a multicenter database. Patients were divided into groups according to PABD (either PABD or NoPABD). Propensity weighting was used to create matched cohorts of PABD and NoPABD patients. Allogeneic (ALLO) exposure, autologous (AUTO) wastage (unused AUTO), and complication rates were compared between groups.

RESULTS

Four hundred twenty-eight patients were identified as meeting eligibility criteria. Sixty patients were treated with PABD, of whom 50 were matched to 50 patients who were not treated with PABD (NoPABD). Nearly one-third of patients in the PABD group (18/60, 30%) did not receive any autologous transfusion and donated blood was wasted. In 6 of these cases (6/60, 10%), patients received ALLO blood transfusions without AUTO. In 9 cases (9/60, 15%), patients received ALLO and AUTO blood transfusions. Overall rates of transfusion of any type were similar between groups (PABD 70% [42/60], NoPABD 75% [275/368], p = 0.438). Major and minor in-hospital complications were similar between groups (Major PABD 10% [6/60], NoPABD 12% [43/368], p = 0.537; Minor PABD 30% [18/60], NoPABD 24% [87/368], p = 0.499). When controlling for potential confounders, PABD patients were more likely to receive some transfusion (OR 15.1, 95% CI 2.1-106.7). No relationship between PABD and ALLO blood exposure was observed, however, refuting the concept that PABD is protective against ALLO blood exposure. In the matched cohorts, PABD patients were more likely to sustain a major perioperative cardiac complication (PABD 8/50 [16%], NoPABD 1/50 [2%], p = 0.046). No differences in rates of infection or wound-healing complications were observed between cohorts.

CONCLUSIONS

Preoperative autologous blood donation was associated with a higher probability of perioperative transfusions of any type in patients with ASD. No protective effect of PABD against ALLO blood exposure was observed, and no risk of perioperative infectious complications was observed in patients exposed to ALLO blood only. The benefit of PABD in patients with ASD remains undefined.

Blood transfusion in primary total shoulder arthroplasty: incidence, trends, and risk factors in the United States from 2000 to 2009

BACKGROUND

Total shoulder arthroplasty (TSA) may be associated with substantial blood loss, and some patients require perioperative blood transfusion. Possible blood transfusion methods include predonated autologous blood transfusion, perioperative autologous blood transfusion, and allogeneic blood transfusion (ALBT). The purposes of the present study were to assess the incidence and recent trends over time of blood transfusion in TSA and analyze patient and hospital characteristics that affect the risk of ALBT.

METHODS

This study used national hospital discharge data from the National Inpatient Sample between 2000 and 2009. The data were used to generate the overall blood transfusion rate, and linear regression was used to assess trends in transfusion patterns over time. Logistic regression analysis was performed to analyze which patient and hospital characteristics independently influence the likelihood that a given patient undergoes ALBT.

RESULTS

The overall blood transfusion rate (ie, the proportion of patients who received at least 1 transfusion of any kind) was 6.7%. This rate increased over time, from 4.9% in 2000 to 7.1% in 2009 (P < .001). Risk factors associated with ALBT included age, gender, race, insurance status, hospital region, and hospital annual caseload.

CONCLUSIONS

The increase in overall blood transfusion rate in TSA found in the present study may be related to factors specific to TSA, such as the introduction of reverse total shoulder arthroplasty during the study period. A variety of patient and hospital characteristics contribute to the risk of undergoing ALBT.

The efficacy of combined use of intraarticular and intravenous tranexamic acid on reducing blood loss and transfusion rate in total knee arthroplasty

The purpose of this study is to investigate the effect of preoperative intravenous (IV) and intraoperative topical administration of tranexamic acid (TXA) in total knee arthroplasty (TKA). A total of 120 patients were and randomly allocated to either topical group, combined group, or control group. The mean total blood loss was lower in the combined and topical groups (705 mL and 579 mL, respectively) in comparison with control group (949 mL, P < 0.001). There was a significant difference in transfusion rate among groups (P = 0.009). The postoperative hemoglobin drop and total drain amount were significantly less in the combined group compared to other groups. In conclusion, combining preoperative IV injection and topical administration of TXA can effectively reduce blood loss and transfusion rate.