Who Is Still Receiving Blood Transfusions After Primary and Revision Total Joint Arthroplasty?

Over the Past Decade, Preoperative Anemia Has Become a Greater Predictor of Transfusions After Total Knee Arthroplasty

BACKGROUND

With advancements in perioperative blood management and the use of tranexamic acid, the rate of transfusions after total knee arthroplasty (TKA) has substantially decreased. As these principles are refined, other modifiable risk factors, such as preoperative anemia, may play an increasingly important role in transfusion risk for patients undergoing TKA.

METHODS

A multicenter, national database was utilized to identify patients undergoing TKA from 2010 to 2021. Anemia was defined by World Health Organization definitions as < 12 g/dL for women and < 13 g/dL for men. A predictive model was created using backwards elimination logistic regression to predict transfusion risk, controlling for demographic and medical covariates. The coefficient of anemia was then analyzed for each year. The trend over time was fitted with a best-fit linear regression equation.

RESULTS

There were 509,117 patients who underwent TKA, and had a mean age of 67 years (range, 18 to 89). There were 57,716 (11%) patients who were anemic preoperatively, and 15,426 (3%) of patients required a transfusion. Rate of transfusion decreased from 10.6% in 2010 to 0.6% in 2021. The odds ratio associated with anemia as a predictor of transfusion increased from 3.1 (95% confidence interval: 2.1 to 4.6) in 2010 to 14.0 (95% confidence interval: 8.9 to 24) in 2021.

CONCLUSIONS

The results of this study demonstrate that the importance of preoperative anemia as a predictor of transfusion has increased over the past decade as rates of transfusion have decreased. As perioperative blood management protocols improve, preoperative anemia should be considered an important focus of intervention to reduce the risk of transfusion prior to TKA.

LEVEL OF EVIDENCE

III.

An observational study of an adjusted patient blood management protocol intended to lower rates of transfusion following total knee arthroplasty in patients with preoperative anemia

BACKGROUND

Patients with preoperative anemia have a higher risk of requiring blood transfusion after major orthopedic surgery due to increased blood loss and closer transfusion thresholds. Various patient blood management (PBM) policies aim to reduce transfusion rates. This observational study aimed to investigate blood loss and evaluate the effectiveness of an adjusted surgical PBM protocol in patients with anemic chronic disease (ACD) undergoing elective total knee arthroplasty (TKA).

METHODS

A consecutive cohort of patients underwent elective unilateral TKA with an adjusted PBM protocol. The protocol consisted of epoetin (EPO) alfa therapy prescribed by the surgeon, routine administration of tranexamic acid (TXA), and standardized postoperative pharmacologic prophylaxis for thromboembolism. The performance of this PBM protocol was analyzed in patients with a baseline hemoglobin level of less than 12 g/dl. Hemoglobin levels were controlled at admission, on postoperative day (POD) 1, and on POD 7 ± 1. A bleeding index (BI-7) was used as an estimate of blood loss up until POD 7. Multiple linear regression was used to assess whether there were any differences in BI-7 between ACD- and ACD + patients.

RESULTS

A total of 751 patients with complete hemoglobin monitoring were included in the study. Of these patients, 68 (9.1%) had a baseline hemoglobin concentration of less than 12 g/dl (ACD group). In this group, 28 patients (41.2%) received preoperative EPO therapy. The mean adjusted BI-7 for the study population was 3.0 (95% CI, 2.9 to 3.0) g/dl in the ACD- group and 2.3 (95% CI, 2.0-2.6) g/dl in the ACD + group. The difference in BI-7 was statistically significant (difference, 0.6 [95% CI: 0.3 to 0.9] g/dl, p < 0.001). No major complications occurred in the ACD + group, whereas there were three complications in the ACD- group (p = 1.00).

CONCLUSIONS

ACD patients undergoing TKA did not have an increased risk of bleeding or bleeding complications with the use of the adjusted PBM protocol. None of ACD patients required transfusion. ACD patients undergoing TKA experienced significantly less blood loss than patients with no preoperative anemia with the use of the adjusted PBM. We now consider the use of EPO in ACD patients with no nutritional deficiencies undergoing TKA at a baseline hemoglobin level of 11 g/dl. However, this should be validated in larger cohorts with a higher prevalence of ACD patients.

Risk of blood transfusion following total hip arthroplasty: A national database study from 367,894 patients

Purpose

A growing elderly population in the United States coupled with improvement in surgical techniques have resulted in more elderly individuals undergoing total hip arthroplasty (THA). As such, risk factors associated with increased risk of blood transfusion following THA, which has been linked to various detrimental outcomes, must be better understood. This study aims to identify co-morbidities associated with blood transfusion following THA.

Methods

Using the Nationwide Inpatient Sample (NIS) database, we selected patients that received a THA from 2016 to 2019 using ICD-10CMP codes. Patients were classified into a "blood transfusion" or "no transfusion" groups and data pertaining to demographics, co-morbidities, and events during hospital stays were compared between the groups.

Results

Our study dataset included 367,894 patients from the NIS database that underwent a THA from 2016 to 2019. 12,900 (3.5 %) patients received a blood transfusion after their THA and were classified as "blood transfusion group." The remaining 354,994 patients were classified as the "no transfusion group." Elective admission was found to decrease the odds of a blood transfusion following a THA (compared to nonelective THA: odd's ratio 0.283; p value < 0.001). Multivariate analysis demonstrated sickle cell disease, liver cirrhosis, and dialysis exhibited the greatest increase in odds of blood transfusion after a THA by 4.81- (p < 0.001), 3.02- (p < 0.001), and 2.22-fold (p < 0.001), respectively. Looking at patient demographics, male sex increased odds of postoperative transfusion by 1.99 (p < 0.001) while Caucasian ethnicity decreased odds of postoperative transfusion by 0.65 (p < 0.001).

Conclusion

Blood transfusion has a low occurrence in the early post-operative period following THA (3.6 % of patients). Sickle cell disease, liver cirrhosis, dialysis, SLE, and heart pathologies were the comorbidities found to be most significantly associated with an increased risk of blood transfusion after a THA. Additionally, both mortality and non-elective admissions were significantly more prevalent in the "blood transfusion" group.

Validation of Machine Learning Model Performance in Predicting Blood Transfusion After Primary and Revision Total Hip Arthroplasty

BACKGROUND

The rates of blood transfusion following primary and revision total hip arthroplasty (THA) remain as high as 9% and 18%, respectively, contributing to patient morbidity and healthcare costs. Existing predictive tools are limited to specific populations, thereby diminishing their clinical applicability. This study aimed to externally validate our previous institutionally developed machine learning (ML) algorithms to predict the risk of postoperative blood transfusion following primary and revision THA using national inpatient data.

METHODS

Five ML algorithms were trained and validated using data from 101,266 primary THA and 8,594 revision THA patients from a large national database to predict postoperative transfusion risk after primary and revision THA. Models were assessed and compared based on discrimination, calibration, and decision curve analysis.

RESULTS

The most important predictors of transfusion following primary and revision THA were preoperative hematocrit (<39.4%) and operation time (>157 minutes), respectively. All ML models demonstrated excellent discrimination (area under the curve (AUC) >0.8) in primary and revision THA patients, with artificial neural network (AUC = 0.84, slope = 1.11, intercept = -0.04, Brier score = 0.04), and elastic-net-penalized logistic regression (AUC = 0.85, slope = 1.08, intercept = -0.01, and Brier score = 0.12) performing best, respectively. On decision curve analysis, all 5 models demonstrated a higher net benefit than the conventional strategy of intervening for all or no patients in both patient cohorts.

CONCLUSIONS

This study successfully validated our previous institutionally developed ML algorithms for the prediction of blood transfusion following primary and revision THA. Our findings highlight the potential generalizability of predictive ML tools developed using nationally representative data in THA patients.

No Blood Loss Increase in Cementless vs. Cemented Fixation Following Bilateral Total Knee Arthroplasty: A Propensity Score Matching Study

Background and Objectives: Recent advancements in three-dimensional printing technology have enhanced the biologic fixation of cementless total knee arthroplasty (TKA), therefore increasing the utilization of newer-generation cementless implants. However, the lack of sealing and tamponade effect of cement on the resected bone surface after cementless TKA raises concerns regarding the potential for greater blood loss compared to cemented TKA. The aim of this study was to (1) compare blood loss and transfusion rates between cementless and cemented TKAs and (2) identify the risk factor for higher blood loss in patients who underwent 1-week-interval staggered bilateral (SB) TKA. Materials and Methods: This retrospective, propensity-matched study included 54 cementless and 53 cemented SB TKAs performed by a single surgeon from 2019 to 2023 with a single implant that has similar design features in both cementless and cemented implants. All patients underwent 1-week-interval SB TKA and received the same patient blood management (PBM) and rehabilitation protocol. The estimated total blood loss (TBL), transfusion rate, and total hemoglobin drop were assessed. Patients were categorized according to TBL into average TBL and higher TBL groups. Univariate and multiple logistic regression analyses were performed to identify risk factors for higher blood loss. Results: There was no difference in TBL between cementless and cemented TKA groups (1233 ± 299 and 1282 ± 309 mL, respectively; p > 0.05). In addition, no between-group differences in the transfusion rate and mean total hemoglobin drop were observed. The logistic regression analyses revealed that whether TKA was cementless or cemented was not associated with higher blood loss; rather, the only identified risk factor was the pre-TKA patient blood volume (odd ratio 1.001, 95% confidence interval 1.000-1002, p = 0.026). Conclusions: Contemporary cementless fixation does not increase blood loss or transfusion rates compared to cemented fixation in patients undergoing 1-week-interval staggered bilateral TKA.

Efficacy and safety of single- and double-dose intravenous tranexamic acid in hip and knee arthroplasty: a systematic review and meta-analysis

OBJECTIVE

With the increasing prevalence of osteoarthritis of the hip and knee, total joint replacement, the end-stage treatment, provides pain relief and restoration of function, but is often associated with massive blood loss. Tranexamic acid (TXA) has been reported to reduce perioperative blood loss in hip or knee arthroplasty. However, the optimal dose of TXA administration remains controversial. Therefore, we performed a meta-analysis combining data from 5 trials comparing the efficacy and safety of one fixed dose of 1 g intravenously administered TXA with two doses of 1 g each administered intravenously for hip or knee arthroplasty.

METHODS

PubMed, Medline, Embase, Web of Science, and The Cochrane Library were searched from January 2000 to February 2023. Our meta-analysis included randomized controlled trials and cohort studies comparing the efficacy and safety of different doses of intravenous TXA (IV-TXA) for THA or TKA. The observation endpoints included total blood loss, postoperative hemoglobin drop, blood transfusion rate, length of hospital stay, incidence of deep venous thrombosis (DVT), and incidence of pulmonary embolism (PE). Meta-analysis was performed according to Cochrane's guidelines and PRISMA statement. The Danish RevMan5.3 software was used for data merging.

RESULTS

Five cohort studies involving 5542 patients met the inclusion criteria. Our meta-analysis showed that the two groups were significantly higher in total blood loss (mean difference (MD) = - 65.60, 95% confidence interval (CI) [- 131.46, 0.26], P = 0.05); blood transfusion rate (risk difference (RD) = 0.00, 95% CI [- 0.01, 0.02], P = 0.55); postoperative hemoglobin (MD = 0.02, 95% CI [- 0.09, 0.13], P = 0.31); postoperative hospital stay days (MD = - 0.13), 95% CI [- 0.35, 0.09], P = 0.25); DVT (RD = 0.00, 95% CI [- 0.00, 0.01], P = 0.67); PE (RD = 0.00, 95% CI [- 0.01, 0.00], P = 0.79). There was some inherent heterogeneity due to variance in sample size across each major study.

CONCLUSION

1 dose of 1 g and 2 doses of 1 g IV-TXA each time have similar effects on reducing blood loss, blood transfusion rate, postoperative hemoglobin level, and postoperative hospital stay after TKA or THA, without increasing the risk of postoperative complications risk. For patients at high risk of thromboembolic events, one dose of 1 g TXA throughout surgery may be preferred. However, higher-quality RCT is needed to explore the optimal protocol dose to recommend the widespread use of TXA in total joint arthroplasty. Trial registration We conducted literature selection, eligibility criteria evaluation, data extraction and analysis on the research program registered in Prospero (CRD42023405387) on March 16, 2023.

A mapping review on preoperative prognostic factors and outcome measures of revision total knee arthroplasty

To map literature on prognostic factors related to outcomes of revision total knee arthroplasty (rTKA), to identify extensively studied factors and to guide future research into what domains need further exploration. We performed a systematic literature search in MEDLINE, Embase, and Web of Science. The search string included multiple synonyms of the following keywords: "revision TKA", "outcome" and "prognostic factor". We searched for studies assessing the association between at least one prognostic factor and at least one outcome measure after rTKA surgery. Data on sample size, study design, prognostic factors, outcomes, and the direction of the association was extracted and included in an evidence map. After screening of 5,660 articles, we included 166 studies reporting prognostic factors for outcomes after rTKA, with a median sample size of 319 patients (30 to 303,867). Overall, 50% of the studies reported prospectively collected data, and 61% of the studies were performed in a single centre. In some studies, multiple associations were reported; 180 different prognostic factors were reported in these studies. The three most frequently studied prognostic factors were reason for revision (213 times), sex (125 times), and BMI (117 times). Studies focusing on functional scores and patient-reported outcome measures as prognostic factor for the outcome after surgery were limited (n = 42). The studies reported 154 different outcomes. The most commonly reported outcomes after rTKA were: re-revision (155 times), readmission (88 times), and reinfection (85 times). Only five studies included costs as outcome. Outcomes and prognostic factors that are routinely registered as part of clinical practice (e.g. BMI, sex, complications) or in (inter)national registries are studied frequently. Studies on prognostic factors, such as functional and sociodemographic status, and outcomes as healthcare costs, cognitive and mental function, and psychosocial impact are scarce, while they have been shown to be important for patients with osteoarthritis.

Spinal versus General Anesthesia in Contemporary Revision Total Hip Arthroplasties

INTRODUCTION

Spinal anesthesia is increasingly used in complex patient populations including revision total hip arthroplasties (THAs). This study aimed to investigate the pain control, length of stay (LOS), and complications associated with spinal versus general anesthesia in a large institutional series of revision THAs.

METHODS

We retrospectively identified 4,767 revision THAs (4,533 patients) from 2001 to 2016 using our institutional total joint registry. Of these cases, 86% had general and 14% had spinal anesthesia. Demographics between groups were similar with mean age of 66 years, 52% women, and mean BMI of 29. Complications including all-cause re-revisions and reoperations were studied. Data were analyzed using an inverse probability of treatment weighted model based on propensity score that accounted for patient and surgical factors. The mean follow-up was 7 years.

RESULTS

Patients treated with spinal anesthesia required fewer postoperative oral morphine equivalents (OMEs) (P<0.001) and had lower numeric pain rating scale scores (P<0.001). Spinal anesthesia had a decreased LOS (4.2 vs. 4.8 days; P=0.007), fewer cases of altered mental status (AMS; Odds Ratio (OR) 3.1, P=0.001), fewer blood transfusions (OR 2.3, P<0.001), fewer intensive care unit (ICU) admissions (OR 2.3, P<0.001), fewer re-revisions (OR 1.6, P=0.04), and fewer reoperations (OR 1.5, P=0.02).

DISCUSSION

Spinal anesthesia was associated with lower OME use and reduced LOS in this large cohort of revision THAs. Furthermore, spinal anesthesia was associated with fewer cases of AMS, transfusion, ICU admission, re-revision, and reoperation after accounting for numerous patient and operative factors.

Predisposing factors for allogeneic blood transfusion in patients with ankylosing spondylitis undergoing primary unilateral total hip arthroplasty: a retrospective study

BACKGROUND

The transfusion rate is relatively high in patients with ankylosing spondylitis (AS) undergoing total hip arthroplasty (THA). However, relevant studies focusing on the predisposing factors for transfusion with a large sample size are lacking. This study aimed to investigate the incidence of and risk factors for allogeneic blood transfusion in patients with AS undergoing primary unilateral THA.

METHODS

This retrospective study included 331 patients with AS who underwent primary unilateral THA between 2011 and 2021. Relevant parameters were collected through a chart review. Multivariate logistic regression analysis was conducted to identify possible factors associated with perioperative allogeneic blood transfusion.

RESULTS

A total of 113 (34.1%) patients received perioperative allogeneic blood transfusions. Factors related to receiving an allogeneic blood transfusion included prolonged operative duration (odds ratio [OR] per 10 min = 1.139, P = 0.047), increased estimated intraoperative blood loss (OR per 100 mL = 1.348, P < 0.001), and increased postoperative drainage volume (OR per 100 mL = 1.235, P = 0.024). A higher body mass index (BMI) (OR = 0.914, P = 0.012), perioperative tranexamic acid (TXA) use (OR = 0.166, P < 0.001), and a higher preoperative hemoglobin level (OR per 1 g/dL = 0.744, P = 0.004) decreased the risk of transfusion.

CONCLUSIONS

In patients with AS undergoing THA, prolonged operative duration, increased estimated intraoperative blood loss, and increased postoperative drainage volume were found to be risk factors for transfusion, whereas a higher BMI, perioperative TXA use, and a higher preoperative hemoglobin level were protective factors. These results may aid in developing a better perioperative management strategy, ultimately reducing the need for transfusion.

Routine Type and Screens Are Unnecessary in Primary Total Joint Arthroplasty: Follow-up After a Change in Practice

Background

Routine type and screens (T&S) prior to total hip (THA) and total knee arthroplasty (TKA) are common despite low transfusion rates. Our institution implemented a practice change after previously demonstrating a transfusion rate of 1.06%. The purpose of this study is to present the follow-up data 1 year after the practice change of discontinuing routine T&S orders in primary total joint arthroplasty.

Methods

A practice change was implemented discontinuing routine T&S orders prior to elective primary total joint arthroplasties. We retrospectively reviewed prospectively collected data on preoperative T&S, hemoglobin values, transfusion rates, bleeding disorders, and anticoagulation status.

Results

A total of 663 patients were included in the study (273 THAs and 390 TKAs). The cumulative transfusion rate was 0.75. No patients received an intraoperative transfusion. Three patients (1.1%) received a postoperative transfusion after THA, and 3 patients (0.5%) received a transfusion after TKA. The mean preoperative hemoglobin in the transfused patients was 12.1 g/dL. Thirteen patients underwent a preoperative T&S (2.0%), and only 2 required transfusion (15.4%). Only 1 patient who required transfusion was on preoperative anticoagulation, and no patients with bleeding disorders required transfusions. Discontinuing routine T&S resulted in an estimated cost savings of $124,325.50.

Conclusions

Discontinuation of routine T&S did not result in any adverse consequences. If required, T&S can safely be performed intraoperatively or postoperatively. Surgeons may consider obtaining a T&S if their preoperative hemoglobin is less than 11-12 g/dL or if significant blood loss is expected in a complex primary total joint arthroplasty.

Are Morbidly Obese Patients Equally Benefitting From Care Improvements in Total Hip Arthroplasty?

BACKGROUND

Morbidly obese patients have increased rates of complications following primary total hip arthroplasty (THA) and it is not clear whether improvements in THA care pathways are equally benefitting these patients. The purpose of this study is to assess if reductions in complications have similarly improved for both morbidly obese and non-morbidly obese patients after THA.

METHODS

Patients undergoing primary THA between 2011 and 2019 were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Patients were stratified by body mass index (BMI) <40 and ≥40 kg/m². Thirty-day rates of infectious complications, readmissions, reoperation, and any complication were assessed. Trends in complications were compared utilizing odds ratios and multivariate analyses.

RESULTS

In total, 234,334 patients underwent THA and 16,979 (7.8%) had BMI ≥40 kg/m². Patients with BMI ≥40 kg/m² were at significantly higher odds for readmission, reoperation, and infectious complications. Odds for any complication were lower for morbidly obese patients in 2011, not different from 2012 to 2014, and higher from 2015 to 2019 compared to lower BMI patients. Odds for any non-transfusion complication were higher for morbidly obese patients and there was no improvement for either group over the study period. There were improvements in rates of readmission and reoperation for patients with BMI <40 kg/m² and readmission for BMI >40 kg/m².

CONCLUSION

Odds for readmission and reoperation for non-morbidly obese patients and readmission for morbidly obese patients improved from 2011 to 2019. Reductions in transfusions are largely responsible for improvements in overall complication rates. Although morbidly obese patients remain at higher risk for complications, there does not appear to be a growing disparity in outcomes between morbidly obese and non-morbidly obese patients.