Blood transfusion in primary total hip and knee arthroplasty. Incidence, risk factors, and thirty-day complication rates

Prediction of transfusion risk after total knee arthroplasty: use of a machine learning algorithm

INTRODUCTION

Total knee arthroplasty (TKA) carries a significant hemorrhagic risk, with a non-negligible rate of postoperative transfusions. The blood-sparing strategy has evolved to reduce blood loss after TKA by identifying the patient's risk factors preoperatively. In practice, a blood count is often performed postoperatively but rarely altering the patient's subsequent management. This study aimed to identify the preoperative variables associated with hemorrhagic risk, enabling the creation of a machine-learning model predictive of transfusion risk after total knee arthroplasty and the need for a complete blood count.

HYPOTHESIS

Based on preoperative data, a powerful machine learning predictive model can be constructed to estimate the risk of transfusion after total knee arthroplasty.

MATERIAL AND METHODS

This retrospective single-centre study included 774 total knee arthroplasties (TKA) operated between January 2020 and March 2023. Twenty-five preoperative variables were integrated into the machine learning model and filtered by a recursive feature elimination algorithm. The most predictive variables were selected and used to construct a gradient-boosting machine algorithm to define the overall postoperative transfusion risk model. Two groups were formed of patients transfused and not transfused after TKA. Odds ratios were determined, and the area under the curve evaluated the model's performance.

RESULTS

Of the 774 TKA surgery patients, 100 were transfused postoperatively (12.9%). The machine learning predictive model included five variables: age, body mass index, tranexamic acid administration, preoperative hemoglobin level, and platelet count. The overall performance was good with an area under the curve of 0.97 [95% CI 0.921 - 1], sensitivity of 94.4% [95% CI 91.2 - 97.6], and specificity of 85.4% [95% CI 80.6 - 90.2]. The tool developed to assess the risk of blood transfusion after TKA is available at https://arthrorisk.com.

CONCLUSION

The risk of postoperative transfusion after total knee arthroplasty can be predicted by a model that identifies patients at low, moderate, or high risk based on five preoperative variables. This machine learning tool is available on a web platform that is accessible to all, easy to use, and has a high prediction performance. The model aims to limit the need for routine check-ups, depending on the risk presented by the patient.

LEVEL OF EVIDENCE

II; diagnostic study.

J-shaped association of operation duration and blood transfusion risk in patients undergoing primary total knee arthroplasty

PURPOSE

Blood transfusion is a common perioperative complication of primary total knee arthroplasty (TKA) that can lead to adverse outcomes, prolonged hospital stays, and increased medical costs. The purpose of our study was to explore the risk factors for blood transfusion and to establish whether operation duration is independently related to blood transfusion risk in patients undergoing primary TKA after adjusting for other covariates.

METHODS

This was a secondary analysis of data from a retrospective cohort study involving patients who underwent primary TKA in Singapore. The patients' baseline data, comorbidity, and surgical characteristics were collected. The independent variable was operation duration and the dependent variable was blood transfusion events. Patients were divided into three groups according to operation durations (90 and 120 min). Univariate logistic regression was used to explore the risk factors associated with blood transfusion after primary TKA. Multivariate analysis was used to assess the independent effect of operation duration on blood transfusion risk after adjusting for other covariates. Additionally, we performed subgroup analyses to identify specific groups, test the robustness of the relationships, and explore whether there were interactions between the different variables. Furthermore, restricted cubic splines (RCS) were used to identify the relationship between the two variables.

RESULTS

A total of 2,562 patients were included in the study, of whom 136 (5.61%) had a transfusion event. Operation durations were 95.55 ± 36.93 and 83.86 ± 26.29 min for blood transfused and non-transfused patients, respectively. Univariate logistic regression analysis showed that age, BMI, ASA status, Hb level, OSA, CHF, creatinine level > 2 mg/dL, and anaesthesia type were risk factors for blood transfusion. After adjusting for all covariates, multivariate logistic regression models showed that operation duration was positively associated with blood transfusion risk (odds ratio [OR] = 1.87, 95% CI = 1.174-2.933, P = 0.007). Compared to patients with an operation duration of less than 90 min, those with an operation duration of more than 120 min had a 2.141-fold increased risk of blood transfusion (OR = 2.141, 95% CI = 1.035-4.265, P = 0.035). Stratified analysis results showed that the association persisted in patients aged > 50 years, Chinese, BMI > 30 kg/m 2, Hb level > 11 g/dL, ASA status levels 2 and 3, general anaesthesia, and unilateral primary TKA. A non-linear (P-non-linear = 0.30) and J-shaped relationship was identified. The risk of transfusion increased as the operation duration decreased or exceeded the inflection point (73.2 min).

CONCLUSION

Our study demonstrated a non-linear and J-shaped relationship between operation duration and blood transfusion events in patients undergoing primary TKA. Blood transfusion risk was the lowest when the operation duration was 73.2 min. A shorter operation duration implies irregular surgical procedures and incomplete intraoperative haemostasis, leading to increased perioperative blood loss and blood transfusion. These results will be useful for clinical decision-making.

Incidence and risk factors of blood transfusion after total knee arthroplasty: A retrospective nationwide inpatient sample database study

Introduction

Common postoperative complications of total knee arthroplasty (TKA) include blood transfusion. Although risk factors and incidence of blood transfusion have been studied through national databases, the relative impact of each risk factor needs to be synthesized over a longer time period into a new model need to be revised.

Material and methods

Patient data were extracted from the National Inpatient Sample (NIS), which is the largest hospital care database in the US, and analyse patient data retrospectively from 2010 through 2019. The final data included the patients undergoing TKA. The final analysis assessed the demographics of patients, type of insurance, type of hospital, length of stay (LOS), preoperative comorbidities, total charge, inpatient mortality, medical-surgical postoperative complications.

Results

After extracting data from the NIS database, a total of 1,250,533 patients with TKA were included in the analysis, and the rate of transfusion was 6.60 %. TKA patients who receive blood transfusion had longer LOS (from 2-3 days to 3-4 days), more preoperative comorbidities, higher inpatient mortality rate, and increased total charge (P < 0.001). Moreover, postoperative complications associated with inpatients included sepsis, acute myocardial infarction and shock. Elective admission and private insurance were also regarded as protective factors.

Conclusion

Blood transfusion could bring postoperative complications to patients, which were also linked to health costs and risks. It was also a common preoperative comorbidities for older patients who underwent TKA. Through better blood management strategies, we could reduce patient transfusion rates and improve clinical outcomes.Level of Evidence: Diagnostic Level Ⅲ.

Worsening of anemia increases the risks of complications and prolonged length of stay following revision total shoulder arthroplasty

Background

There are no studies currently in the literature that assesses complications following revision total shoulder arthroplasty (TSA) in patients with varying severity of anemia. The purpose of this study was to determine the impact of preoperative anemia severity on postoperative complications following revision TSA.

Methods

Patients undergoing revision TSA from 2013 to 2019 were queried in a national database. Based on previous studies' definitions of anemia, three subgroups were stratified: patients without anemia (hematocrit >36% for women, hematocrit >39% for men), patients with mild anemia (hematocrit 33% to 36% for women, hematocrit 33% to 39% for men) and patients with moderate to severe anemia (hematocrit <33% for both women and men). In this analysis, patient demographics, comorbidities, and postoperative complications were compared between the three groups.

Results

Of 1559 total patients undergoing revision TSA, 1178 patients (75.6%) did not have anemia, 255 (16.3%) had mild anemia, and 126 (8.1%) had moderate/severe anemia. Following adjustment on multivariate analysis, patients with mild anemia were more likely to have postoperative transfusion and extended length of stay compared to non-anemic patients. Patients with moderate/severe anemia were at increased risk of postoperative transfusion, sepsis, extended length of stay, and reoperation compared to non-anemic patients.

Discussion

From mild anemia to moderate/severe anemia, there was a stepwise increase in the risk of postoperative complications. Our study showed that there is clinical value in the preoperative correction of anemia for these patients as it relates to complications and hospital stay.

Level of Evidence

III.

Blood Transfusion in the Age of Tranexamic Acid: Who Needs a Type and Screen Before Total Hip Arthroplasty?

BACKGROUND

Modern surgical protocols, particularly the use of tranexamic acid (TXA), have reduced, but not eliminated, blood transfusions surrounding total hip arthroplasty (THA). Identifying patients at risk for transfusion remains important for risk reduction and to determine type and screen testing.

METHODS

We reviewed 6,405 patients who underwent primary, unilateral THA between January 2014 and January 2023 at a single academic institution, received TXA, and had preoperative hemoglobin (Hgb) values. We compared demographics, baseline Hgb levels, and surgical details between patients who were and were not transfused. Data were analyzed utilizing multivariate regression and receiver operating characteristic curve analysis.

RESULTS

The overall perioperative and intraoperative transfusion rates were 3.4 and 1.0%, respectively. Patients who were older, women, and American Society of Anesthesiologists class >II demonstrated an increased risk of transfusion. Risk of transfusion demonstrated an inverse correlation with preoperative Hgb levels, a bimodal association with body mass index, and a direct correlation with age, surgical time, and estimated blood loss on multivariate analysis. The receiver operating characteristic analysis demonstrated a preoperative Hgb cutoff of 12 g/dL for predicting any transfusion. Above the threshold of 12 g/dL, total and intraoperative transfusions were rare, with rates of 1.7 and 0.3%, respectively. Total and intraoperative transfusion rates with Hgb between 11 and 12 g/dL were 14.3 and 4.6%, respectively. Below 11 g/dL, total and intraoperative transfusion rates were 27.5 and 10.1%, respectively.

CONCLUSIONS

In the age of TXA, blood transfusion is rare in THA when preoperative Hgb is >12 g/dL, challenging the need for universal type and screening. Conversely, patients who have Hgb < 11.0 g/dL, remain at substantial risk for transfusion. Between Hgb 11 and 12 g/dL, patient age, sex, body mass index, American Society of Anesthesiologists classification, anticipated estimated blood loss, and surgical time may help predict transfusion risk and the need for a perioperative type and screen.

LEVEL OF EVIDENCE

III.

Risk factor analysis and establishment of a nomogram model to predict blood loss during total knee arthroplasty

PURPOSE

The risk factors for excessive blood loss and transfusion during total knee arthroplasty (TKA) remain unclear. The present study aimed to determine the risk factors for excessive blood loss and establish a predictive model for postoperative blood transfusion.

METHODS

This retrospective study included 329 patients received TKA, who were randomly assigned to a training set (n = 229) or a test set (n = 100). Univariate and multivariate linear regression analyses were used to determine risk factors for excessive blood loss. Univariate and multivariate logistic regression analyses were used to determine risk factors for blood transfusion. R software was used to establish the prediction model. The accuracy and stability of the models were evaluated using calibration curves, consistency indices, and receiver operating characteristic (ROC) curve analysis.

RESULTS

Risk factors for excessive blood loss included timing of using a tourniquet, the use of drainage, preoperative ESR, fibrinogen, HCT, ALB, and free fatty acid levels. Predictors in the nomogram included timing of using a tourniquet, the use of drainage, the use of TXA, preoperative ESR, HCT, and albumin levels. The area under the ROC curve was 0.855 (95% CI, 0.800 to 0.910) for the training set and 0.824 (95% CI, 0.740 to 0.909) for the test set. The consistency index values for the training and test sets were 0.855 and 0.824, respectively.

CONCLUSIONS

Risk factors for excessive blood loss during and after TKA were determined, and a satisfactory and reliable nomogram model was designed to predict the risk for postoperative blood transfusion.

Evaluation of efficacy and safety of perioperative tranexamic acid during Primary Total Knee Arthroplasty: A randomized, Clinical trial

Background

Primary total knee arthroplasty (TKA) is the gold standard treatment for degenerative joint disease, but it carries a significant risk of blood loss that may require transfusion. Various techniques are implemented to reduce the possibility of the need for allogeneic blood transfusion (ABT). To this end, this study aims to assess the effectiveness of tranexamic acid (TXA) in decreasing blood loss following primary TKA.

Materials and methods

This study is a randomized controlled study of 100 cases of primary total knee arthroplasty conducted in Damascus from July 2021 to September 2022, followed up with every patient for six months. The patients were randomized into two groups. We compared intraoperative, postoperative, total, and hidden blood loss and perioperative complications.

Results

We observed a statistically significant difference between the two groups in total calculated, hidden, and postoperative blood loss. However, this difference does not seem clinically significant, as we didn't find a significant difference in allogeneic blood transfusion between the groups. Regarding complications, the TXA group had five cases of superficial wound infection and six cases of deep venous thrombosis. In contrast, the control group had eight cases of superficial wound infection and five cases of deep venous thrombosis.

Conclusion

Our study suggests that the role of TXA in primary unilateral total knee arthroplasty in the hands of an experienced surgeon might be overrated. The reduced blood loss did not seem to have clinical importance and didn't affect the transfusion rates.

Increasing severity of preoperative anemia is associated with higher postoperative medical and surgical complications after primary shoulder arthroplasty

BACKGROUND

Anemia is a major cause of morbidity worldwide and compounds numerous medical conditions. Studies have found associations between anemia and both medical and surgical complications after shoulder arthroplasty (SA); however, most of these studies have used commercially available national databases with limited information on outcomes and typically short-term follow-up. Our study sought to evaluate the midterm outcomes of primary SA at a single institution when stratified by the degree of preoperative anemia.

METHODS

Between 2000 and 2020, 5231 primary SA (477 hemiarthroplasties, 2091 anatomic total SA, and 2335 reverse SA) with preoperative hematocrit values available and a minimum follow-up of 2 years were collected from a single-institution joint registry database. The severity of anemia was subclassified as no anemia (hematocrit >39% for males, >36% for females; n = 4194 [80.2%]), mild anemia (hematocrit 33%-39% for males, 33%-36% for females; n = 742 [14.2%]), and moderate-to-severe anemia (hematocrit <33% for both males and females; n = 295 [5.6%]). The mean follow-up time for the entire cohort was 5.9 years (range, 2-22 years). Medical and surgical complications, reoperations, revisions, and implant survivorship were assessed.

RESULTS

SA with moderate-to-severe anemia had the highest rate of nonfatal and nontransfusion medical complications (5.1%) relative to the nonanemic (1.2%; P < .001) and mild anemic groups (1.5%; P < .001). Similarly, SA with moderate-to-severe anemia had the highest rate of surgical complications (19.3%) compared with mild anemia (14.3%; P = .044) and no anemia (11.6%; P < .001). Postoperative transfusion was most frequent in the moderate-to-severe anemia cohort (40.3%) compared with the mild anemia (14.2%; P < .001) and nonanemic groups (2.5%; P < .001). Furthermore, SA who received postoperative transfusions had a higher risk of nonfatal medical complications (8.2% vs. 1.0%; P < .001), 90-day mortality (1.5% vs. 0.03%; P = .001), and surgical complications (19.5% vs. 12.0%; P < .001) when compared with those without transfusion.

CONCLUSIONS

Moderate-to-severe anemia (hematocrit <33% for both males and females) was identified in approximately 5.6% of patients who underwent SA at a single institution and was associated with increased medical and surgical complications. Patients who received postoperative transfusions presented elevated rates of medical complications, 90-day mortality, and surgical complications. Health care teams should be aware of these risks in order to provide more individualized medical optimization and postoperative monitoring.

Association between perioperative red blood cell transfusions and postoperative venous thromboembolism: A systematic review and meta-analysis

BACKGROUND

Whether perioperative red blood cell transfusions increases the risk of postoperative venous thromboembolism is controversial and uncertain.We aims to explore the relationship between perioperative red blood cell transfusions and the risk of postoperative venous thromboembolism by conducting a meta-analysis.

OBJECTIVE

To conduct a meta-analysis to systematically evaluate the relationship between perioperative red blood cell transfusions and the risk of postoperative venous thromboembolism.

METHODS

PubMed, Embase, Cochrane, and Web of Science databases were searched to identify studies examining the relationship between perioperative red blood cell transfusions and the risk of postoperative venous thromboembolism. The databases were searched from establishment to August 2023.Two researchers independently screened literature and extracted data according to inclusion and exclusion criteria. Newcastle-ottawa Scale was used for quality assessment. Meta-analysis of data was performed using RevMan 5.4 software.

RESULTS

A total of 15 studies involving 1,880,990 patients were included in this study.Meta-analysis showed that perioperative red blood cell transfusions increased the risk of postoperative venous thromboembolism [OR = 1.61, 95%CI (1.37, 1.89), P < 0.001]. Subgroup analyses showed that the transfusion dose,transfusion timing,study population and follow-up time were closely related to the risk of postoperative venous thromboembolism.

CONCLUSIONS

In summary, this meta-analysis demonstrated a significant positive association between perioperative red blood cell transfusions and postoperative venous thromboembolism.Healthcare professionals should pay attention to the influence of blood transfusions on postoperative venous thromboembolism, strengthen management and prevention.

Outcomes of different perioperative management strategies of patients on chronic anticoagulation in elective total hip and knee arthroplasty: a systematic review

INTRODUCTION

There are currently different management guidelines for patients undergoing elective total hip arthroplasty (THA) or total knee arthroplasty (TKA) that are on long-term anticoagulation. The timing of discontinuation and restarting the anticoagulation is challenging during the postoperative care, which often involves general practitioners and physiotherapists.

METHODS

The systematic review followed the PRISMA guidelines and included 3 databases: PubMed/MEDLINE, EMBASE, and Web of Science Core Collection. It was registered in the International Prospective Register for Systematic Reviews and Meta-analysis (PROSPERO) under the registration number: CRD42023408906. The risk of bias assessment was performed using the Methodological index for non-randomized studies (MINORS) criteria.

RESULTS

Six retrospective studies involving 727 patients with therapeutic anticoagulation (1,540 controls) for elective THA, TKA and revision arthroplasty have been included. The follow-up ranged from 30 days to 1 year postoperatively. All studies evaluated outcomes of warfarin therapeutic anticoagulation versus prophylactic dosages of one or more of the following: warfarin, aspirin, low-molecular-weight heparin (LMWH) and unfractionated low-dose heparin (UFH). One study did not discontinue therapeutic anticoagulation. Two studies reported no significant differences in complications between groups, whilst 3 studies had significantly higher rates of superficial wound infections, revision surgeries, postoperative haematomas, and prosthetic joint infections (PJI).

CONCLUSION

Different anticoagulation-related perioperative management strategies achieve different outcomes following elective arthroplasty in patients with therapeutic chronic anticoagulation. There is contradictory evidence regarding the need for the discontinuation of therapeutic warfarin. Retrospective data showed that individual risk stratification with multi-modal prophylaxis resulted in minimal complications.

LEVEL OF EVIDENCE

Systematic Review of Level III studies.

Routine pretransfusion testing before primary total hip or knee arthroplasty are an expensive and wasteful routine. Systematic review and meta-analysis

BACKGROUND

The excessive routine ordering of pretransfusion tests (blood typing, screening, and cross-matching) for surgical cases incurs significant unnecessary costs and places an undue burden on transfusion services. This study aims to systematically review the literature regarding the necessity of routine pretransfusion tests before total hip arthroplasty (THA) or total knee arthroplasty (TKA) and summarize their outcomes.

STUDY METHODS

A systematic review and meta-analysis were performed. The study's characteristics, the prevalence of over-ordering pretransfusion tests, transfusion rates, and potential cost savings to the healthcare system were analyzed.

RESULTS

The study included 17,667 patients. Pooled results revealed a 96.3% over-ordering pretransfusion test rate (95% CI: 0.92-1.00; p < 0.001) among patients undergoing primary THA or TKA. The pooled prevalence of hospital transfusion rate was 3.6%. Notably, there were statistically significant differences in preoperative hemoglobin (Hb) levels between patients not requiring transfusion (Hb = 13.9 g/dl; 95% CI 12.59-15.20; p < 0.001) and those needing transfusion (Hb = 11.9 g/dl; 95% CI 10.69-13.01; p < 0.001) (p = 0.03). The per-patient total cost savings ranged from 28.63 to 191.27 dollars.

DISCUSSION

Our study suggests that routine pre-transfusion testing for all patients undergoing primary THA or TKA may be unnecessary. We propose limiting pretransfusion test orders to patients with preoperative hemoglobin levels below 12 g/dl in unilateral primary TKA or THA. This targeted approach can result in significant cost savings for healthcare systems and transfusion services by reducing the over-ordering of pretransfusion tests in these surgical procedures.

Analysis of the incidence and risk factors of blood transfusion in total knee revision: a retrospective nationwide inpatient sample database study

OBJECTIVE

This study sought to determine the incidence and risk factors of blood transfusion among patients undergoing total knee revision (TKR) using a nationwide database.

METHODS

A retrospective data analysis was conducted based on the Nationwide Inpatient Sample (NIS), enrolling patients who underwent TKR from 2010 to 2019 with complete information. The patients were divided into two groups based on whether they received blood transfusion or not. The demographic characteristics (race, sex, and age), length of stay (LOS), total charge of hospitalization, hospital characteristics (admission type, insurance type, bed size, teaching status, location, and region of hospital), hospital mortality, comorbidities, and perioperative complications were analyzed. Finally, we conducted univariate and multivariate logistic regression to identify factors that were associated with TKR patients to require blood transfusion.

RESULTS

The NIS database included 115,072 patients who underwent TKR. Among them, 14,899 patients received blood transfusion, and the incidence of blood transfusion was 13.0%. There was a dramatic decrease in the incidence over the years from 2010 to 2019, dropping from 20.4 to 6.5%. TKR patients requiring transfusions had experienced longer LOS, incurred higher total medical expenses, utilized Medicare more frequently, and had increased in-hospital mortality rates (all P < 0.001). Independent predictors for blood transfusion included advanced age, female gender, iron-deficiency anemia, rheumatoid disease, chronic blood loss anemia, congestive heart failure, coagulopathy, uncomplicated diabetes, lymphoma, fluid and electrolyte disorders, metastatic carcinoma, other neurological diseases, paralysis, peripheral vascular disorders, pulmonary circulation disorders, renal failure, valvular disease, and weight loss. In addition, risk factors for transfusion in TKR surgery included sepsis, acute myocardial infarction, deep vein thrombosis, pulmonary embolism, gastrointestinal bleeding, heart failure, renal insufficiency, pneumonia, wound infection, lower limb nerve injury, hemorrhage/seroma/hematoma, wound rupture/non healing, urinary tract infection, acute renal failure, and postoperative delirium.

CONCLUSIONS

Our findings highlight the importance of recognizing the risk factors of blood transfusion in TKR to reduce the occurrence of adverse events.

The Efficacy and Safety of Tranexamic Acid in Total Hip and Knee Arthroplasty: A Literature Review

Historically, total hip arthroplasty (THA) and total knee arthroplasty (TKA) have been associated with significant perioperative blood loss and a relatively high rate of allogeneic blood transfusions. However, in recent years, tranexamic acid (TXA), a competitive inhibitor of tissue plasminogen activator, inhibiting fibrinolysis of existing thrombi, has substantially decreased the need for blood transfusion in THA and TKA. Various administration strategies have been studied, but there remains a lack of consensus on an optimal route and dosing regimen, with intravenous and topical regimens being widely used. A growing body of literature has demonstrated the safety and efficacy of TXA in primary and revision THA and TKA to reduce blood loss, allogeneic transfusions, and complications; it is associated with lowered lengths of stay, costs, and readmission rates.

Trends, complications, and readmission of allogeneic red blood cell transfusion in primary total hip arthroplasty in china: a national retrospective cohort study

INTRODUCTION

Decrease in allogenic red blood cell (RBC) transfusion rates following total hip arthroplasty (THA) has been reported in the United States, but whether other countries share the same trend remains unclear. Additionally, the relation of allogenic RBC transfusion to the risk of complications in THA remains controversial. Using the Chinese national inpatient database, the current study aimed to examine trends, complications, charges, and readmission patterns of allogeneic RBC transfusion in THA.

MATERIALS AND METHODS

Patients undergoing primary THA between 2013 and 2019 were included, and then stratified into the transfusion and the non-transfusion group based on the database transfusion records. A generalized estimating equation model was used to investigate trends in transfusion rates. After propensity-score matching, a logistic regression model was used to compare the complications, rates and causes of 30-day readmission between two groups.

RESULTS

A total of 10,270 patients with transfusion and 123,476 patients without transfusion were included. Transfusion rates decreased from 19.11% in 2013 to 9.94% in 2019 (P for trend < 0.001). After matching, no significant differences in the risk of of in-hospital death (odds ratio [OR], 4.00; 95% confidence interval [CI] 0.85-18.83), wound infection (OR 0.72; 95%CI 0.45-1.17), myocardial infarction (OR 1.17; 95%CI 0.62-2.19), deep vein thrombosis (OR 1.25; 95%CI 0.88-1.78), pulmonary embolism (OR 2.25; 95%CI 0.98-5.17), readmission rates (OR 1.07; 95%CI 0.88-1.30) and readmission causes were observed between two groups. However, the transfusion group had higher hospitalization charges than the non-transfusion group (72,239.89 vs 65,649.57 Chinese yuan [CNY], P < 0.001).

CONCLUSIONS

This study found that allogeneic RBC transfusion in THA was not associated with the increased risk of complications and any-cause readmission. However, the currently restrictive transfusion policy should be continued because excessive blood transfusion may increase the socioeconomic burden.

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.

A Decline in Overutilization of Transfusion after Total Knee Arthroplasty Using Pharmacological Agents for Patient Blood Management in South Korea: An Analysis Based on the Korean National Health Insurance Claims Database from 2008 to 2019

Background

This study aimed to evaluate the annual trends of transfusion rates and utilization of blood management agents in total knee arthroplasty (TKA) based on the operation type and to analyze the risk factors of transfusion after TKA.

Methods

Using the Korean National Insurance claims database of 797,106 primary and revision TKAs between January 2008 and October 2019, data on the patients' characteristics, comorbidities, utilization of transfusion, and blood management agents were collected. The patients were categorized into three groups based on the operation type: primary, revision, and simultaneous bilateral TKA. The transfusion rate and utilization of blood management agents (intraoperative tranexamic acid [TXA] and preoperative iron supplements) were compared, and the risk factors for transfusion were evaluated.

Results

After excluding the inaccurate data, 730,554 arthroplasties (636,292 primary, 10,540 revision, and 41,861 simultaneous bilateral TKAs) were identified. The transfusion rates of primary, revision, and simultaneous bilateral TKAs in 2019 were 64.0%, 67.7%, and 68.9%, respectively, which were significantly decreased compared with 83.2%, 88.0%, and 92.5% in 2008, respectively (p < 0.001). Conversely, the utilization of intraoperative TXA and preoperative iron supplements was significantly increased from 4.6% and 13.8%, respectively, in 2008 to 52.4% and 27.0%, respectively, in 2019 (p < 0.001). The utilization of intraoperative TXA and preoperative iron supplements significantly lowered the risk of transfusion after TKA (odds ratio [OR], 0.20; p < 0.001 and OR, 0.71; p < 0.001).

Conclusions

The transfusion rate after TKA decreased gradually from 83.5% to 64.5% between 2008 and 2019 in South Korea corresponding with the increased utilization of blood management agents. Therefore, consistent attention to patient blood management should be emphasized to reduce the transfusion rate after TKA.

Direct Anterior Versus Posterior Approach for Total Hip Arthroplasty Performed for Displaced Femoral Neck Fractures

OBJECTIVES

To compare perioperative, 90-day, and 1-year postoperative complications and outcomes between the direct anterior approach (DAA) and the posterior approach for total hip arthroplasty in geriatric patients with displaced femoral neck fractures (FNFs).

DESIGN

Retrospective cohort study.

SETTING

Multicenter Health care Consortium.

PATIENTS

Seven-hundred and nine patients 60 years or older with acute displaced FNFs between 2009 and 2021.

INTERVENTION

Total hip arthroplasty using either DAA or posterior approach.

MAIN OUTCOME MEASUREMENTS

Rates of postoperative complications including dislocations, reoperations, and mortality at 90 days and 1 year postoperatively. Secondary outcome measures included ambulation capacity at discharge, ambulation distance with inpatient physical therapy, discharge disposition, and narcotic prescription quantities (morphine milligram equivalents).

RESULTS

Through a multivariable regression analysis, DAA was associated with significantly shorter operative time ( B = -6.89 minutes; 95% confidence interval [CI] -12.84 to -0.93; P = 0.024), lower likelihood of blood transfusion during the index hospital stay (adjusted odds ratios = 0.54; 95% CI 0.27 to 0.96; P = 0.045), and decreased average narcotic prescription amounts at 90 days (B = -230.45 morphine milligram equivalents; 95% CI -440.24 to -78.66; P = 0.035) postoperatively. There were no significant differences in medical complications, dislocations, reoperations, and mortality at 90 days and 1 year postoperatively.

CONCLUSION

When comparing the DAA versus posterior approach for total hip arthroplasty performed for displaced FNF, DAA was associated with shorter operative time, lower likelihood of blood transfusion, and lower 90-day postoperative narcotic prescription amounts.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Risk factors for blood transfusion and postoperative anaemia following total knee arthroplasty

Aims

Blood transfusion and postoperative anaemia are complications of total knee arthroplasty (TKA) that are associated with substantial healthcare costs, morbidity, and mortality. There are few data from large datasets on the risk factors for these complications.

Methods

We retrospectively reviewed the records of TKA patients from a single tertiary care institution from February 2016 to December 2020. There were a total of 14,901 patients in this cohort with a mean age of 67.9 years (SD 9.2), and 5,575 patients (37.4%) were male. Outcomes included perioperative blood transfusion and postoperative anaemia, defined a priori as haemoglobin level < 10 g/dl measured on the first day postoperatively. In order to establish a preoperative haemoglobin cutoff, we investigated a preoperative haemoglobin level that would limit transfusion likelihood to ≤ 1% (13 g/dl) and postoperative anaemia likelihood to 4.1%. Risk factors were assessed through multivariable Poisson regression modelling with robust error variance.

Results

In multivariable analyses, each gram of tranexamic acid reduced transfusion likelihood by 39% (adjusted risk ratio (ARR) 0.61 (95% confidence interval (CI) 0.47 to 0.78)). Risk factors associated with an increased risk of transfusion included operating time (ARR 2.07 (95% CI 1.54 to 2.77)) and drain use (ARR 1.73 (95% CI 1.34 to 2.24)).

Conclusion

In this study, we found that increased tranexamic acid dosing, decreased operating time, and decreased drain use may reduce transfusions following TKA. We also established a single preoperative haemoglobin cutoff of 13 g/dl that could help minimize transfusions and reduce postoperative complete blood counts.

Predicting Factors for Blood Transfusion in Primary Total Knee Arthroplasty Using a Machine Learning Method

INTRODUCTION

Acute blood loss anemia requiring allogeneic blood transfusion is still a postoperative complication of total knee arthroplasty (TKA). This study aimed to use machine learning models for the prediction of blood transfusion after primary TKA and to identify contributing factors.

METHODS

A total of 2,093 patients who underwent primary TKA at our institution were evaluated using data extracted from the hospital quality improvement database to identify patient demographics and surgical variables that may be associated with blood transfusion. A multilayer perceptron neural network (MPNN) machine learning algorithm was used to predict risk factors for blood transfusion and factors associated with increased length of stay. Statistical analyses including bivariate correlate analysis, Chi-Square test, and Student t-test were performed for demographic analysis and to determine the correlation between blood transfusion and other variables.

RESULTS

The results demonstrated important factors associated with transfusion rates, including preoperative hemoglobin level, preoperative creatinine level, length of surgery, simultaneous bilateral surgeries, tranexamic acid usage, American Society of Anesthesiologists Physical Status score, preoperative albumin level, ethanol usage, preoperative anticoagulation medications, age, and TKA type (conventional versus robotic-assisted). Patients who underwent a blood transfusion had a markedly greater length of stay than those who did not. The MPNN machine learning model achieved excellent performance across discrimination (AUC = 0.894).

DISCUSSION

The MPNN machine learning model showed its power as a statistical analysis tool to predict the ranking of factors for blood transfusion. Traditional statistics are unable to differentiate importance or predict in the same manner as a machine learning model.

CONCLUSION

This study demonstrated that MPNN for the prediction of patient-specific blood transfusion rates after TKA represented a novel application of machine learning with the potential to improve preoperative planning for treatment outcomes.

Computer-assisted Navigation in Lumbar Spine Instrumented Fusions: Comparison of In-hospital and 30-Day Postoperative Complications With Nonnavigated Fusions in a National Database

OBJECTIVE

To compare in-hospital and 30-day postoperative complications for lumbar spine operations with and without use of computer-assisted navigation.

METHODS

Patients who underwent 1-level to 3-level lumbar spinal instrumentation and fusions 2011 to 2014 were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Emergent procedures and patients aged younger than 18 years were excluded. Patients whose surgery involved the use of computer-assisted navigation were propensity score matched 1:4 based on preoperative demographics and comorbidities to operations without the use of navigation. Multivariate analysis was done to compare postoperative complications.

RESULTS

In total, 8,500 patients (average age: 60.7 ± 12.9, male 3,866, female 4,634) were analyzed (1,700 navigation, 6,800 Non-Navigated). Operations with navigation had significantly fewer overall complications (24% vs. 27%, P = 0.008; odds ratio [OR] = 0.83; CI = 0.73 to 0.95), fewer minor complications (20% vs. 24%, P = 0.002; OR = 0.80; CI = 0.70 to 0.91), fewer blood transfusions (17% v. 20%, P = 0.013; OR = 0.82; CI = 0.71 to 0.95), more wound dehiscences (0.4% vs. 0.8%, P = 0.022; OR = 2.16; CI = 1.12,4.19), and shorter average lengths of hospital stays (4.8 ± 4.8 vs. 5.1 ± 5.8 days, P = 0.01). Operations with computer navigation had significantly longer average surgical times (247 ± 129 vs 221 ± 115 minutes, P < 0.001). No significant differences were observed in 30-day revision rates, readmissions, and mortality.

CONCLUSION

Although use of computer-assisted navigation in short-segment lumbar spine fusions (1 to 3 levels) did not decrease revision rates for screw misplacement within 30 days postoperatively, it independently reduced the frequency of blood transfusions and minor complications and decreased hospital lengths of stay compared with operations without navigation. These benefits came at the expense of increased surgical times and wound dehiscences within 30 days postoperatively. Given the inherent limitations of large national databases, these results warrant confirmation through prospective, multicenter investigations.

Anemia Severity and the Risks of Postoperative Complications and Extended Length of Stay Following Primary Total Elbow Arthroplasty

BACKGROUND

Anemia is a modifiable risk factor that may influence postoperative complications following orthopedic surgical procedures. The objective was to determine the influence of preoperative anemia severity on postoperative complications and length of stay (LOS) following total elbow arthroplasty (TEA).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program registry was queried from 2006 to 2019 for patients undergoing primary TEA. Using the World Health Organization definitions of anemia, patients undergoing TEA were stratified into 3 cohorts: nonanemia (hematocrit >36% for women, >39% for men), mild anemia (hematocrit 33%-36% for women, 33%-39% for men), and moderate-to-severe anemia (hematocrit <33% for both women and men). Patient demographics, surgical time, LOS, and postoperative complications were compared between the groups. A P value <.004 was considered significant.

RESULTS

After exclusion, 589 patients, of whom 369 (62.6%) did not have anemia, 129 (21.9%) had mild anemia, and 91 (15.5%) had moderate/severe anemia, were included. Increasing severity of anemia was associated with an increased average hospital LOS (2.30 vs 2.81 vs 4.91 days, P < .001). There was a statistically significant increase in blood transfusions (1.08% vs 7.75% vs 17.58%, P < .001), major complications (9.21% vs 17.83% vs 34.07%, P < .001), any complications (11.11% vs 23.26% vs 36.26%, P < .001), and extended LOS ≥6 days (6.23% vs 6.98% vs 31.87%, P < .001) with increasing severity of anemia. Multivariate analysis identified moderate-to-severe anemia was significantly associated with major complications and extended LOS (P < .001).

CONCLUSIONS

Preoperative anemia is a modifiable risk factor for medical and surgical complications within 30 days of TEA.

Predisposing factors for allogeneic blood transfusion in patients with rheumatoid arthritis undergoing primary unilateral total knee arthroplasty

BACKGROUND

To determine the incidence and identify the predisposing factors for allogeneic blood transfusion (ABT) in patients with rheumatoid arthritis (RA) undergoing primary unilateral total knee arthroplasty (TKA).

METHODS

A total of 702 patients with RA who underwent primary unilateral TKA between 2003 and 2022 at a single center, were retrospectively enrolled. Patients were stratified into the ABT and non-ABT groups. Data on patient demographics, laboratory parameters, and disease- and surgery-related parameters were collected from chart reviews and compared between the ABT and non-ABT groups. Multivariate logistic regression analysis was conducted to identify the possible factors associated with postoperative ABT.

RESULTS

A total of 173 (24.6%) patients underwent ABT after surgery. Significant risk factors for ABT included the degree of flexion contracture [odds ratio (OR) = 1.018, P = 0.005] and thickness of insertion (OR = 1.170, P = 0.014). Conversely, body mass index (OR = 0.937, P = 0.018), preoperative hemoglobin level (OR = 0.973, P < 0.001), and intraoperative use of tranexamic acid (TXA) (OR = 0.119, P < 0.001) were associated with a lower risk of ABT in TKA.

CONCLUSION

We identified the significant risk and protective factors for ABT during TKA in patients with RA. This information could be helpful in optimizing perioperative blood management strategies during these surgeries.

Prediction of suitable outpatient candidates following revision total knee arthroplasty using machine learning

Aims

To identify variables independently associated with same-day discharge (SDD) of patients following revision total knee arthroplasty (rTKA) and to develop machine learning algorithms to predict suitable candidates for outpatient rTKA.

Methods

Data were obtained from the American College of Surgeons National Quality Improvement Programme (ACS-NSQIP) database from the years 2018 to 2020. Patients with elective, unilateral rTKA procedures and a total hospital length of stay between zero and four days were included. Demographic, preoperative, and intraoperative variables were analyzed. A multivariable logistic regression (MLR) model and various machine learning techniques were compared using area under the curve (AUC), calibration, and decision curve analysis. Important and significant variables were identified from the models.

Results

Of the 5,600 patients included in this study, 342 (6.1%) underwent SDD. The random forest (RF) model performed the best overall, with an internally validated AUC of 0.810. The ten crucial factors favoring SDD in the RF model include operating time, anaesthesia type, age, BMI, American Society of Anesthesiologists grade, race, history of diabetes, rTKA type, sex, and smoking status. Eight of these variables were also found to be significant in the MLR model.

Conclusion

The RF model displayed excellent accuracy and identified clinically important variables for determining candidates for SDD following rTKA. Machine learning techniques such as RF will allow clinicians to accurately risk-stratify their patients preoperatively, in order to optimize resources and improve patient outcomes.

Predictive and protective factors for allogenic blood transfusion in total knee arthroplasty. A retrospective cohort study

Background

This study aimed to identify the predictive and protective factors of blood transfusion in patients undergoing total knee arthroplasty (TKA) and therefore determine the profile of patients with low and high risk of blood transfusion after arthroplasty.

Methods

We conducted a retrospective study with all patients who underwent primary TKA between January 2017 and December 2019 (n = 1.028 patients) in our institution. Information about allogenic transfusion was collected from medical records to determine the incidence, the predictive and protective factors of blood transfusion. All cases of blood transfusions were documented as well the number of units and the moment of each transfusion. We performed univariate and multivariate logistic regression analyses to identify the independent risk and protective factors.

Results

The total transfusion rate was 11%, 1.1% at intraoperative and 9,9% at postoperative period. The independent risk factors for transfusion were female gender (OR 1.64), older age (>55yo, OR > 2) higher surgical risk (ASA III, OR 3.07), lower preoperative hemoglobin levels (p = 0.024), post-traumatic arthritis (OR 4.11) and use of postoperative drains (OR 1.81) The protective factors for transfusion were male gender (OR 0.60), obesity (IMC >30, OR 0.60) and use of intravenous tranexamic acid intraoperatively (OR 0.40).

Conclusions

We conclude that in addition to the well-established risk factors for blood transfusion such as advanced age, low hemoglobin levels and high surgical risk, we can add post-fracture arthroplasty, non-use of tranexamic acid and the use of postoperative joint drain.

Prediction of Non-Home Discharge Following Total Hip Arthroplasty in Geriatric Patients

Introduction

The majority of total hip arthroplasty (THA) patients are discharged home postoperatively, however, many still require continued medical care. We aimed to identify important characteristics that predict nonhome discharge in geriatric patients undergoing THA using machine learning. We hypothesize that our analyses will identify variables associated with decreased functional status and overall health to be predictive of non-home discharge.

Materials and Methods

Elective, unilateral, THA patients above 65 years of age were isolated in the NSQIP database from 2018-2020. Demographic, pre-operative, and intraoperative variables were analyzed. After splitting the data into training (75%) and validation (25%) data sets, various machine learning models were used to predict non-home discharge. The model with the best area under the curve (AUC) was further assessed to identify the most important variables.

Results

In total, 19,840 geriatric patients undergoing THA were included in the final analyses, of which 5194 (26.2%) were discharged to a non-home setting. The RF model performed the best and identified age above 78 years (OR: 1.08 [1.07, 1.09], P < .0001), as the most important variable when predicting non-home discharge in geriatric patients with THA, followed by severe American Society of Anesthesiologists grade (OR: 1.94 [1.80, 2.10], P < .0001), operation time (OR: 1.01 [1.00, 1.02], P < .0001), anemia (OR: 2.20 [1.87, 2.58], P < .0001), and general anesthesia (OR: 1.64 [1.52, 1.79], P < .0001). Each of these variables was also significant in MLR analysis. The RF model displayed good discrimination with AUC = .831.

Discussion

The RF model revealed clinically important variables for assessing discharge disposition in geriatric patients undergoing THA, with the five most important factors being older age, severe ASA grade, longer operation time, anemia, and general anesthesia.

Conclusions

With the rising emphasis on patient-centered care, incorporating models such as these may allow for preoperative risk factor mitigation and reductions in healthcare expenditure.

The natural course of hemoglobin levels after allogenic blood transfusion in total knee arthroplasty

We retrospectively investigated the natural course of hemoglobin levels after allogenic blood transfusion in total knee arthroplasty. All patients were treated according to the same clinical pathway, and blood tests were performed on the same day. All blood tests were done on pre-op, immediate post-op, midnight of op day, 1st, 2nd, 3rd, 5th, 7th, and 11th day after surgery. Of the total 593 cases, a total of 197 cases (33.2%) were performed within 3 days of surgery. Hemoglobin level was significantly lowest on the 3rd day after surgery and tended to increase afterwards in the non-transfusion group. In the case of blood transfusion on the day of surgery, the hemoglobin level showed an increase on the next day and then showed a minimum value on the fifth day of surgery and then increased. The same pattern was identified when blood transfusion was done on the 1st and 2nd day of surgery. However, when blood transfusion was done on the 3rd day, the hemoglobin level showed a steady increase afterwards. The hemoglobin level of total knee arthroplasty patients with no blood transfusion was the lowest on the 3rd day after surgery and increased afterwards. If blood transfusion was done within 2 days after surgery, the hemoglobin level was the lowest on the 5th day after surgery and increased afterwards. If blood transfusion was done on the 3rd day after surgery, the hemoglobin level increased afterwards.

Adverse Events After Total Hip Arthroplasty are not Sufficiently Characterized by 30-Day Follow-Up: A Database Study

BACKGROUND

Many previous studies of total hip arthroplasty (THA) have focused on adverse events occurring within 30 days of surgery. Studies examining 90-day postoperative adverse events have typically not focused on the timing of adverse events within that period. The current study evaluated the rate and timing of adverse events within 90 days of THA.

METHODS

Adult THA patients between 2010 and 2020 Q3 were identified from a large administrative dataset. Rates and timing of 90-day adverse events were determined. The median, interquartile range, and middle 80% were calculated based on the time of diagnosis for each adverse event. These were also dichotomized as occurring before or after 30 days and predictive factors for later adverse events were determined.

RESULTS

Overall, 81,158 adverse events were noted, of which 56,500 (69.0%) were diagnosed within 30 days of surgery and 25,355 (31.0%) were diagnosed 31-90 days after surgery. The proportion of adverse events occurring 31-90 days after surgery ranged from 6% (transfusion) to 45% (wound dehiscence). Patients experiencing a later adverse event were more likely to be women and to have higher Elixhauser Comorbidity Index (ECI) scores.

CONCLUSION

Almost one-third of adverse events following THA were diagnosed between postoperative days 31 and 90, highlighting the importance of looking beyond 30 days when estimating patients' risk of postoperative adverse events. These data may inform future research, patient counseling, and prevention strategies.

Blood-Transfusion Risk Factors after Intramedullary Nailing for Extracapsular Femoral Neck Fracture in Elderly Patients

BACKGROUND

Extracapsular femoral neck fractures (eFNF) are the third most common type of fracture in traumatology. Intramedullary nailing (IMN) is one of the most frequently used ortho-pedic treatments for eFNF. Blood loss is one of the main complications of this treatment. This study aimed to identify and evaluate the perioperative risk factors that lead to blood transfusion in frail patients with eFNF who undergo IMN.

METHODS

From July 2020 to December 2020, 170 eFNF-affected patients who were treated with IMN were enrolled and divided into two groups according to blood transfusion: NBT (71 patients who did not need a blood transfusion), and BT (72 patients who needed blood transfusion). Gender, age, BMI, pre-operative hemoglobin levels, in-ternational normalized ratio (INR) level, number of blood units transfused, length of hospital stay, surgery duration, type of anesthesia, pre-operative ASA score, Charlson Comorbidity Index, and mortality rate were assessed.

RESULTS

Cohorts differed only for pre-operatively Hb and surgery time (p < 0.05).

CONCLUSION

Patients who have a lower preoperative Hb level and longer surgery time have a high blood-transfusion risk and should be closely followed peri-operatively.

Perioperative safety assessment of patients undergoing unilateral or bilateral hip replacements

Introduction

Due to the aging of the world population and the increase of obesity rate, it is expected that the number of joint replacement surgery will continue to increase in the next few years. This study evaluated the safety differences between unilateral and bilateral hip replacement surgeries.

Methods

The data for patients who underwent hip arthroplasty in 2021 and 2022 were examined. The data set included 68 patients who were grouped according to the type of hip replacement needed, sex, age, and body mass index. Total blood loss and operative time were the safety-related indicators used to compare the groups.

Results

Regardless of whether the unilateral replacement group was compared with the overall bilateral replacement group or separately with the staged and simultaneous bilateral replacement groups, simultaneous bilateral replacement surgeries were equally safe as the other types of hip replacements. The total blood loss and operative time for the simultaneous bilateral replacement group were not significantly different from those in the unilateral and staged bilateral replacement groups. For overweight patients, the operative time for simultaneous bilateral replacements was significantly shorter than that for unilateral replacements.

Conclusions

These findings suggest that for patients requiring bilateral hip replacements, the blood loss risk for patients undergoing simultaneous bilateral hip replacements was similar to that for patients undergoing either unilateral or staged bilateral hip replacements. Thus, simultaneous bilateral total hip replacement (THR) are safe and should be considered for candidate patients.

Anemia and formation of deep vein thrombosis before operation in patients with knee osteoarthritis: a cross-sectional study

BACKGROUND

Preoperative anemia is a common complication in knee osteoarthritis (KOA) patients. However, the association between anemia and preoperative deep vein thrombosis (DVT) in osteoarthritis patients remains unknown. The aim of this study was to investigate such association.

METHODS

In this retrospective study, we included 1005 KOA patients undergoing total knee arthroplasty (TKA) in our hospital. According to preoperative hemoglobin levels, the patients were divided into anemia group and non-anemia group. According to the results of Doppler ultrasonography for the lower extremities, the patients were divided into DVT group and non-DVT group. A logistic model was established through propensity score matching (PSM), with anemia before TKA as the dependent variable, DVT-related variable as the covariate, and 0.03 as the Caliper value. The anemia group and non-anemia group were matched at a 1:1 ratio and 310 successfully matched. After matching, logistic regression analysis was used to evaluate the correlation between preoperative anemia and DVT in KOA patients.

RESULTS

In this study, 342 cases (33.6%) had preoperative anemia and 73 cases (7.2%) had DVT before TKA. After matching, 46 DVT cases (7.42%) were found. By using binary logistic regression after PSM, we found that the risk for preoperative DVT formation in TKA patients with preoperative anemia increased by 1.97 times [95% (CI 1.05-3.69)], P = 0.035.

CONCLUSION

Preoperative anemia is considered as an independent risk factor for the formation of preoperative DVT in KOA patients.

TRIAL REGISTRATION

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Efficacy of immediate postoperative intravenous iron supplementation after staged bilateral total knee arthroplasty

BACKGROUND

Approximately 26% of patients undergoing major orthopedic elective procedures have preoperative anemia. This study aimed to investigate the effect of intravenous (IV) iron supplementation on the hemoglobin (Hb) level after staged bilateral total knee arthroplasty (TKA) in patients with or without preoperative anemia.

METHODS

We retrospectively analyzed 418 patients who underwent staged bilateral TKA (1 week interval). The iron group (n = 220) received IV iron isomaltoside immediately after each TKA. The no-iron group (n = 198) was recommended to receive transfusion if postoperative anemia was diagnosed between the first and second TKA. Preoperative anemia was present in 42 (21.2%) and 50 (22.7%) patients in the no-iron and iron groups, respectively. Demographic data, preoperative and postoperative Hb levels, Hb level change (preoperative minus postoperative 6-week Hb level), and blood drainage amount were compared between groups.

RESULTS

The transfusion rate was lower in the iron group than in the no-iron group (96.5% vs. 58.6%, P < 0.001). Overall, the demographic data, preoperative and postoperative 6-week Hb levels, Hb level change, and blood drainage amount were not significantly different between the two groups. Among patients with preoperative anemia, the iron group showed lower Hb level change (0.6 ± 0.9 vs. 0.1 ± 1.1, P = 0.016).

CONCLUSION

Patients with preoperative anemia treated with IV iron showed lower Hb level change than did those without IV iron treatment. Despite the lower transfusion rate, the iron group showed similar postoperative 6-week Hb level and Hb level change to the no-iron group.

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.

Predictors and complications of blood transfusion in rheumatoid arthritis patients undergoing total joint arthroplasty

PURPOSE

Our research investigated predictors of postoperative blood transfusion rate following total joint arthroplasty (TJA) in patients with rheumatoid arthritis (RA) and evaluated the incidence of complications in the transfusion group and non-transfusion group.

METHODS

The authors retrospectively analyzed risk factors among 320 RA patients who underwent elective total hip arthroplasty (THA) or total knee arthroplasty (TKA) from January 2010 to December 2018. Demographic characteristics, laboratory results, medication history, and surgical protocol were gathered from electronic medical records. Univariable and multivariable logistic regression analyses were conducted to measure the impact of relevant variables on the need for transfusions. In addition, we compared the incidence of complications associated with transfusion.

RESULTS

The cohort comprised 320 RA patients, aged 57.4 ± 12.0 years, of whom 137 required postoperative blood transfusions and 183 did not. BMI, type of surgery, duration of surgery, disease activity score 28 (DAS28-CRP), tranexamic acid (TXA) administration, and preoperative hemoglobin (Hb) were all risk factors for transfusion after adjusting for the planned procedure.

CONCLUSION

Previously published predictors, such as BMI, low preoperative hemoglobin, duration of surgery, procedure type (THA), were also identified in our analysis. Moreover, TXA administration and the DAS28-CRP showed the potential to influence risk. The incidence of postoperative complications was increased in patients who received blood transfusions compared to non-transfusion group. Our findings could help to identify RA patient population requiring blood transfusions, to ensure the necessary steps are adopted to limit blood loss and improve blood management strategies. Key Points • The risk factors for blood transfusion in rheumatoid arthritis patients undergoing total joint arthroplasty were BMI, the type of surgery, duration of surgery, TXA administration, DAS28-CRP, and preoperative hemoglobin. • The incidence of postoperative complications was increased in patients who received blood transfusions compared to non-transfusion group.

Prediction of red blood cell transfusion after orthopedic surgery using an interpretable machine learning framework

Objective

Postoperative red blood cell (RBC) transfusion is widely used during the perioperative period but is often associated with a high risk of infection and complications. However, prediction models for RBC transfusion in patients with orthopedic surgery have not yet been developed. We aimed to identify predictors and constructed prediction models for RBC transfusion after orthopedic surgery using interpretable machine learning algorithms.

Methods

This retrospective cohort study reviewed a total of 59,605 patients undergoing orthopedic surgery from June 2013 to January 2019 across 7 tertiary hospitals in China. Patients were randomly split into training (80%) and test subsets (20%). The feature selection method of recursive feature elimination (RFE) was used to identify an optimal feature subset from thirty preoperative variables, and six machine learning algorithms were applied to develop prediction models. The Shapley Additive exPlanations (SHAP) value was employed to evaluate the contribution of each predictor towards the prediction of postoperative RBC transfusion. For simplicity of the clinical utility, a risk score system was further established using the top risk factors identified by machine learning models.

Results

Of the 59,605 patients with orthopedic surgery, 19,921 (33.40%) underwent postoperative RBC transfusion. The CatBoost model exhibited an AUC of 0.831 (95% CI: 0.824-0.836) on the test subset, which significantly outperformed five other prediction models. The risk of RBC transfusion was associated with old age (>60 years) and low RBC count (<4.0 × 10¹²/L) with clear threshold effects. Extremes of BMI, low albumin, prolonged activated partial thromboplastin time, repair and plastic operations on joint structures were additional top predictors for RBC transfusion. The risk score system derived from six risk factors performed well with an AUC of 0.801 (95% CI: 0.794-0.807) on the test subset.

Conclusion

By applying an interpretable machine learning framework in a large-scale multicenter retrospective cohort, we identified novel modifiable risk factors and developed prediction models with good performance for postoperative RBC transfusion in patients undergoing orthopedic surgery. Our findings may allow more precise identification of high-risk patients for optimal control of risk factors and achieve personalized RBC transfusion for orthopedic patients.

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.

Immediate haemoglobin testing in association with a dedicated anaemia clinic: Effectiveness for primary total knee replacement patients

INTRODUCTION

Preoperative anaemia is associated with higher transfusion rates, increased hospital stays and poorer outcomes. Addressing preoperative anaemia is a crucial pillar of Patient Blood Management. Conventionally, patients are listed for surgery and then screened for anaemia in the pre-assessment clinic, followed by referral to their general practitioner. This process involves substantial delays, and poorly treated anaemia often results in perioperative transfusions. We assessed our pathway of immediate haemoglobin testing at the time of listing in conjunction with a dedicated preoperative anaemia clinic for detecting and treating anaemia in primary total knee replacement patients.

MATERIALS AND METHODS

We compared transfusion rates between anaemic patients undergoing a primary total knee replacement who were treated in this pathway with those who were not. We reviewed the preoperative haemoglobin levels, transfusion rates and treatment for all primary total knee arthroplasty patients over three years amounting to 2296.

RESULTS

Transfusion rates were significantly lower in the group treated in this pathway compared to those who were not. The treated group also had significantly higher preoperative haemoglobin levels.Discussion and conclusion: Immediate haemoglobin testing in association with a dedicated preoperative anaemia clinic is effective at detecting and treating anaemia in primary total knee replacement patients and reduces transfusion requirements.

A novel model forecasting perioperative red blood cell transfusion

We aimed to establish a predictive model assessing perioperative blood transfusion risk using a nomogram. Clinical data for 97,443 surgery patients were abstracted from the DATADRYAD website; approximately 75% of these patients were enrolled in the derivation cohort, while approximately 25% were enrolled in the validation cohort. Multivariate logical regression was used to identify predictive factors for transfusion. Receiver operating characteristic (ROC) curves, calibration plots, and decision curves were used to assess the model performance. In total, 5888 patients received > 1 unit of red blood cells; the total transfusion rate was 6.04%. Eight variables including age, race, American Society of Anesthesiologists' Physical Status Classification (ASA-PS), grade of kidney disease, type of anaesthesia, priority of surgery, surgery risk, and an 18-level variable were included. The nomogram achieved good concordance indices of 0.870 and 0.865 in the derivation and validation cohorts, respectively. The Youden index identified an optimal cut-off predicted probability of 0.163 with a sensitivity of 0.821 and a specificity of 0.744. Decision curve (DCA) showed patients had a standardized net benefit in the range of a 5–60% likelihood of transfusion risk. In conclusion, a nomogram model was established to be used for risk stratification of patients undergoing surgery at risk for blood transfusion. The URLs of web calculators for our model are as follows: http://www.empowerstats.net/pmodel/?m=11633_transfusionpreiction.

Optimal Release Timing of Drain Clamping to Reduce Postoperative Bleeding after Total Knee Arthroplasty with Intraarticular Injection of Tranexamic Acid

Background and Objectives: Intraarticular injection of tranexamic acid (IA-TXA) plus drain-clamping is a preferred method of reducing bleeding after total knee arthroplasty (TKA). However, no consensus has been reached regarding the timing of the clamping. The purpose of this study was to determine the optimum duration of drain-clamping after TKA with IA-TXA. Materials and Methods: We retrospectively reviewed 151 patients that underwent unilateral TKA with IA-TXA plus drain-clamping for 30 min, 2 h, or 3 h. The total drained volume was reviewed as the primary outcome, and hematocrit (Hct) reductions, estimated blood loss (EBL), transfusion rates, and wound complications were reviewed as secondary outcomes. Results: The mean total drained volume, Hct reduction, and EBL were significantly less in the 3 h group than in the 30 min group. Between the 2 h and 3 h groups, there was no statistical difference in the mean total drained volume, Hct reduction, or EBL. The proportion of patients who drained lesser than 300 mL was high in the 3 h group. No significant intergroup difference was observed for transfusion volume, transfusion rate, and wound related complications. Conclusions: In comparison of the IA-TXA plus drain-clamping after TKA, there was no difference in EBL between the 2 h group and the 3 h group, but the amount of drainage volume was small in the 3 h group.

The international normalised ratio predicts perioperative complications in revision total hip arthroplasty

BACKGROUND

Standard preoperative protocols in total joint arthroplasty utilise the international normalised ratio (INR) to determine patient coagulation profiles. However, the relevance of preoperative INR values in joint arthroplasty remains controversial. Therefore, we examined (1) the relationship between preoperative INR values and various outcome measures, including, but not limited to: surgical site complications, medical complications, bleeding, number of readmissions, and mortality. Additionally, we sought to determine (2) specific INR values associated with these complications and (3) cutoff INR levels which correlated with specific outcomes. We additionally applied these analyses to (4) examine the relationship between INR and length-of-stay (LOS).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database (ACS-NSQIP) was queried for rTHA procedures performed between 2006 and 2017. INR ranges were used to stratify cohorts: ⩽1.0, 1.0-⩽1.25, 1.25-⩽1.5, >1.5. INR values were determined using receiver operating characteristics (ROC) curves for each outcome of interest. Optimal cutoff INR values for each outcome were then obtained using univariate/multivariate models. 2012 patients who underwent rTHA met inclusion criteria.

RESULTS

Patients with progressively higher INR values had a significantly different risk of mortality within 30 days (p = 0.005), bleeding requiring transfusion (p < 0.001), sepsis (p = 0.002), stroke (p < 0.001), failure to wean from ventilator within 48 hours (p = 0.001), readmission (p = 0.01), and hospital length of stay (p < 0.001). Similar results were obtained when utilising optimal INR cutoff values. When correcting for other factors, the following poor outcomes were significantly associated with the respective INR cutoff values (Estimate, 95% CI, p-value): LOS >4 days (1.67, 1.34-2.08, p < 0.001), bleeding requiring transfusion (1.65, 1.30-2.09, p < 0.001), sepsis (2.15, 1.11-4.17, p = 0.022), and any infection (1.82, 1.01-3.29, p = 0.044).

CONCLUSIONS

Our analysis illustrates a direct relationship between specific preoperative INR levels and poor outcomes following rTHA, including increased LOS, transfusion requirements and infection. Therefore, current INR guideline targets may need to be re-examined when optimising patients for revision arthroplasty.

Comparison of three methods for sealing of the intramedullary femoral canal during total knee arthroplasty; a randomized controlled trial

PURPOSE

The purpose of this randomized controlled study was to examine the effect of sealing the intramedullary canal with a bone or cement plug or leaving it empty on postoperative bleeding and pain MATERIALS AND METHODS: A total of 120 patients with knee osteoarthritis who underwent unilateral TKA participated in the trial and were assigned to one of three groups. The femoral canal was sealed with an autogenous bone plug (Group I) or cement plug (Group II), or it was left open (Group III). Estimated blood loss, Hemoglobin decline, bleeding into the drain, and postoperative pain w compared between groups.

RESULTS

Six patients were excluded due to various reasons, and the remaining 114 patients were included in the final analysis. There were no significant variations in baseline clinical characteristics between the three groups (p > 0.05). Hemoglobin reduction between preoperative and 72 h after the surgery (p: 0.034) and estimated blood loss (p: 0.003) were significantly different between groups. The cement plug group showed the least bleeding. Although there was a significant difference between the cement and empty canal groups (p: 0.03 and p: 0.002, respectively), the difference between the cement and bone groups was similar regarding both hemoglobin reduction and estimated blood loss. The blood volume in the suction drain (p: 0.598) and transfusion rate (p: 0.087) were similar between the groups. VAS at the 12 h after the surgery was similarly high in each group (p: 0.676). It declined at 36 h after surgery, but no significant difference was determined between groups (p: 0.815).

CONCLUSIONS

This study showed that estimated blood loss and hemoglobin reduction were significantly lower in the cement plug group than in the empty canal group. But bone plug group did not show any difference with both empty canal and cement plug groups. Sealing the IM canal or leaving it open did not change the bleeding into the drain, transfusion rate, and postoperative pain between groups. Based on these findings, sealing the IM canal with a cement plug might be recommended to diminish bleeding during TKA despite similar transfusion rates.

LEVEL OF EVIDENCE

Level I, randomized controlled trial.

The effects of a new protocol on blood loss in total knee arthroplasty

The aim of study was to evaluate the efficacy of blood loss prevention with Tranexamic acid in patients undergoing total knee arthroplasty (TKA). The Authors defined a new protocol that foresees the use of Tranexamic acid both pre-intra and post-operatively. Seventy patients indicated for TKA were enrolled. Thirty-five patients (control group) followed standard protocol without Tranexamic acid and the other 35 patients (study group) followed standard protocol with Tranexamic acid. We analyzed the values of hemoglobin (Hb), hematocrit (HCT) and red blood cells (RBCs) both pre-operatively (T0) and post-operatively: immediately after surgery (T1), at one day (T2) and three days post-op (T3). We observed statistical differences at T0 and T3 regarding the Hb, HT and RBCs value between the two groups. Moreover, 11.4% in the study and 28.5% in the control group required blood transfusion. No thrombotic or thrombo-embolic events were reported. We conclude that Tranexamic acid use, as in our protocol, reduces postoperative bleeding in primary knee arthroplasty, with the absence of thrombo-embolic events.

Bipolar Sealers and Tourniquet Use Have Similar Outcomes in Total Knee Arthroplasty

INTRODUCTION

The use of tourniquets and bipolar sealers are effective methods of hemostasis during total knee arthroplasty (TKA). However, their effect on perioperative patient outcomes is unknown. The purpose of this study is to compare the efficacy of tourniquet-less, tourniquet-less with use of a bipolar sealer, and tourniquet use on postoperative pain and surgical outcomes following TKA.

METHODS

A retrospective study of prospectively collected data of 120 primary TKA cases was conducted at an urban academic hospital. Primary outcomes were visual analog scale (VAS) scores and opioid consumption (in morphine milligram equivalents). Demographics, length of stay (LOS), perioperative complications, and change in Knee Injury and Osteoarthritis Outcome Score (ΔKOOS) were also collected. Patients were divided into cohorts based on the use of tourniquet-less with bipolar sealer (TRLB) (n = 40), tourniquet (TR) (n = 40), or tourniquet-less (TRL) (n = 40).

RESULTS

There were no differences in demographic data between each cohort. TRLB, TR and TRL had similar LOS (2.68 ± 1.63 vs 2.29 ± 1.27 vs 2.36 ± 1.42 days; p = 0.472) and VAS pain score on postoperative day 1 (4.68 vs 3.74 vs 3.63; p = 0.209). There were also no differences in opioid consumption at 2 weeks (p = 0.903), 1 month (p = 0.973), 3 months (p = 0.983), or 5 months (p = 0.983) post-operatively. TRLB and TR had comparable improvement in ΔKOOS from baseline to 12 weeks post-operatively (Δ16.58 ± 8.47 vs Δ23.92 ± 14.60; p = 0.254). Compared to the ΔKOOS of TRL (Δ5.19 ± 2.59), TRLB and TR had clinically and statistically greater ΔKOOS improvements (p = 0.009; p = 0.001). The TRL cohort also had a higher readmission rate than TRLB and TR (15% vs 0% vs 5%, p = 0.025).

CONCLUSION

Our findings demonstrate that both bipolar sealer and tourniquet use in TKA are associated with similar postoperative pain levels and LOS in comparison to tourniquet-less only TKA. However, bipolar sealer and tourniquet use may lead to better longer term improvement such as greater PRO score improvement and fewer readmissions.

Evaluation of Blood Loss in Conventional vs MAKOplasty Total Knee Arthroplasty

Background

Methods

Results

Conclusions

Bone Density May Be a Promising Predictor for Blood Loss during Total Hip Arthroplasty

Background: Total hip arthroplasty (THA), which is performed mostly in elderly individuals, can result in substantial blood loss and thereby imposes a significant physical burden and risk of blood transfusion. The femoral neck cut and reamed acetabulum are the main sites of intraoperative bleeding. Whether the bone density in that region can be used to predict the amount of blood loss in THA is unknown. Methods: We retrospectively analyzed adult patients undergoing primary THA in the Department of Orthopedics, Peking Union Medical College Hospital, from January 2018 to January 2020. All these patients underwent primary unilateral THA. Patients had their bone mineral density (BMD) recorded within the week before surgery and were stratified and analyzed for perioperative blood loss. Multivariable regressions were utilized to adjust for differences in demographics and comorbidities among groups. Results: A total of 176 patients were included in the study. Intraoperative blood loss was 280.1 ± 119.56 mL. Pearson correlation analysis showed a significant correlation between blood loss and preoperative bone density of both the femoral greater trochanter (R = 0.245, p = 0.001) and the Ward’s triangle (R = 0.181, p = 0.016). Stepwise multiple linear regression showed that preoperative bone density of the greater trochanter (p = 0.015, 95% CI: 0.004–0.049) and sex (p = 0.002) were independent risk factors for THA bleeding. The area under the receiver operating characteristic curve (AUROC) of the greater trochanter and Ward’s triangle was 0.593 (95% CI: 0.507–0.678, p = 0.035) and 0.603 (95% CI: 0.519–0.688, p = 0.018), respectively. The cutoff T value on the femoral greater trochanter for predicting higher bleeding was −1.75. Conclusions: In THA patients, preoperative bone density values of the femoral greater trochanter and sex could be promising independent predictors for bleeding during surgery. Osteoporosis and female patients might have lower blood loss in the THA operation.

Elective Total Hip Arthroplasties in Nonagenarians-Age Does Matter: A National Surgical Quality Improvement Program Study

BACKGROUND

The aim of this study is to assess the independent effect of age on the risk of postsurgical complications and death in patients undergoing total hip arthroplasty (THA).

METHODS

The National Surgical Quality Improvement Program was used to identify all patients aged 65 years and older who underwent primary THA from 2011 to 2017. Study outcomes were minor complications, major life-threatening complications, and 30-day mortality. Predictors of outcomes were identified using bivariate analyses and age was added into the final logistic regression models with stepwise selection.

RESULTS

A total of 74,361 patients were included in the analysis. Mean (standard deviation) age was 735 years (6.46), median 72.0 years; 1,119 (1.50%) patients were ≥90 years. Females comprised 60.6% of the patient sample. The incidence of major life-threatening complications, minor complications, and death was 939/74,361 (1.3%), 2,098 (2.8%) and 154 (0.2%) respectively. When added to the final models, age was significantly associated with an increased risk of postoperative complications and mortality.

CONCLUSION

Elective THA in relatively healthy nonagenarians should only be considered among patients with disabling osteoarthritis demonstrating a restricted quality of life. Although THA can substantially improve patient wellbeing, our findings suggest that surgeons and patients must consider the impact of age on patient course and outcomes regardless of the presence of comorbidities.

LEVEL OF EVIDENCE

Level II, prognostic study.

Assessment of perioperative total blood loss during total ankle arthroplasty

BACKGROUND

Although many authors have discussed total blood loss after arthroplasty of the knee, hip, and shoulder, reports on perioperative blood loss after total ankle arthroplasty (TAA) are rare. The purpose of this study was to assess total blood loss after TAA and to identify correlated factors.

METHODS

A total of 103 cases (99 patients) of TAA for end-stage ankle osteoarthritis were enrolled in this study. Perioperative total blood loss was divided into intraoperative and postoperative blood loss. The patient-related variables evaluated for total blood loss were age, sex, body mass index, American Society of Anesthesiologists Classification score, comorbidities, history of previous ankle surgery, preoperative use of anticoagulants, platelet count and prothrombin time/international normalized ratio. Operation-related variables including type of anesthesia, operation time, TAA implant, and procedures performed in addition to TAA (if any) were evaluated to analyze correlations with total blood loss. In addition, the rate of transfusions after surgery was identified, and risk factors for transfusion were statistically analyzed.

RESULTS

The total blood loss was mean 795.5±351.1mL, which included 462.2±248.5mL of intraoperative blood loss and 333.2±228.6mL of postoperative blood loss. Sex, TAA implant, and additional bony procedures performed along with TAA were significantly correlated with total blood loss (p=0.039, 0.024, 0.024, respectively) but the other variables were not significant (p>0.05). Transfusions were administered for 4 cases (3.8%) but no risk factors for transfusion could be identified.

CONCLUSION

The total blood loss after TAA was 795.5mL and the rate of transfusions was 3.8%. This study demonstrated that male sex, use of TAA implants with a larger cutting surface, and bony procedures performed in addition to TAA were associated with an increase in total blood loss after TAA. The findings of this study will help surgeons to better predict blood loss and make optimal surgical plans accordingly.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Risk factors for complications within 30 days of operatively fixed periprosthetic femur fractures

BACKGROUND

With a rising number of periprosthetic femur fractures (PPFFs) each year, the primary objective of our study was to quantify risk factors that predict complications following operative treatment of PPFFs.

METHODS

A retrospective cohort study of 231 patients with a periprosthetic femur fracture was conducted at an Academic, Level 1 Trauma Center. The main outcome measurement of interest was complications, as defined by the ACS-NSQIP, within 30 days of surgery.

RESULTS

56 patients had 96 complications. Bivariate analyses revealed ASA score, preoperative ambulatory status, length of stay, discharge disposition, time from admission to surgery, length of surgery, perioperative change in hemoglobin, Charlson comorbidity index, cerebral vascular accident/transient ischemic attack, chronic obstructive pulmonary disease, diabetes mellitus, and receipt of a blood transfusion were associated with development of a complication (p < 0.1). Multivariate logistic regression showed length of stay (OR 1.11, 95% CI 1.03-1.19; p = 0.006), receipt of a blood transfusion (OR 2.48, 95% CI 1.14-5.42; p = 0.02), and diabetes mellitus (OR 2.17, 95% CI 1.03-4.56; p = 0.04) remained independently predictive of complication.

CONCLUSIONS

Length of stay, receipt of a blood transfusion, and diabetes were associated with increased perioperative risk for developing a complication following operative treatment of periprosthetic femur fractures. Methods to decrease length of stay or transfusion rates may mitigate complication risk in these patients.

LEVEL OF EVIDENCE

Prognostic, Level III.

Predict Postoperative Anemia of Patients: Nomogram Construction and Validation

Introduction

The loss of blood is a significant problem in Total Knee Arthroplasty (TKA). Anemia often occurs after such surgeries, leading to serious consequences, such as higher postoperative infection rates and longer hospital stays. Tools for predicting possible anemia can provide additional guidance in realizing better blood management of patients.

Methods

2,165 patients who underwent TKA from 2015 to 2019 in the same medical center were divided into training and validation cohorts. Both univariate and multivariate logistic regression analyses were performed to identify independent preoperative risk factors for anemia. Based on these predictors, a nomogram was established using the area under the curve (AUC), calibration curve (AUC), and the area under the curve (AUC). The model was then applied to the validation cohort, and decision curve analyses (DCA) were also plotted.

Results

Through analysis of both univariate and multivariate logistic regression, five independent predictors were found in the training cohort: female, relatively low BMI, low levels of preoperative hemoglobin, abnormally high levels of ESR, and simultaneously two sides of TKA in the same surgery. The AUCs of the nomogram were 74.6% (95% CI, 71.35%–77.89%) and 68.8% (95% CI, 63.37%–74.14%) of training and the validation cohorts separately. Furthermore, the calibration curves of both cohorts illustrated the consistency of the nomogram with the actual condition of anemia of patients after TKA. The DCA curve was higher for both treat-none and treat-all, further indicating the relatively high practicality of the model.

Conclusion

Female, lower BMI, lower levels of preoperative Hb, simultaneous bilateral TKA, and high levels of preoperative ESR were figured out as five independent risk factors for postoperative anemia (&lt;9.0 g/dL) in patients undergoing TKA. Based on the findings, a practical nomogram was constructed to predict risk of postoperative anemia. The evidence level should be level 4 according to guideline.

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

BACKGROUND

Incidence of blood transfusions after primary and revision total hip and knee arthroplasty (primary total hip arthroplasty [pTHA], revision THA [rTHA], primary total knee arthroplasty [pTKA], and revision TKA [rTKA]) has been decreasing for a multitude of reasons. The purpose of this study was to assess whether transfusion rates have continued to decline and evaluate patient factors associated with transfusions.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program was queried to identify patients undergoing pTHA, pTKA, rTHA, and rTKA between 2011 and 2019. Patients undergoing bilateral procedures and arthroplasty for fracture, infection, or tumor were excluded. Trends in blood transfusions were assessed. Patient factor association with blood transfusions was evaluated using 2018 and 2019 data.

RESULTS

Transfusion rates decreased from 21.4% in 2011 to 2.5% in 2019 for pTHA (P < .0001). For pTKA, transfusion rates declined from 17.6% to 0.7% (P < .0001). In rTHA, the transfusion rate decreased from 33.5% to 12.0% from 2011 to 2019 (P < .0001). Transfusion rates declined from 19.4% to 2.6% for rTKA during the study period (P < .0001). Transfusions were more frequent in patients who were older, female, with more comorbidities, with lower hematocrit, receiving nonspinal anesthesia, and with longer operative time. Lower preoperative hematocrit, history of bleeding disorders, and preoperative transfusion were associated with greater odds for postoperative transfusion after multivariate analysis.

CONCLUSION

Transfusions after both primary and revision total joint arthroplasty have continued to decrease. Studies of arthroplasty complications should account for decreasing transfusions when assessing overall complication rates. Future studies should consider interventions to further reduce transfusions in revision arthroplasty.

Transfusion Trends of Knee Arthroplasty in Korea: A Nationwide Study Using the Korean National Health Insurance Service Sample Data

Knee arthroplasties are strongly associated with blood transfusion to compensate for perioperative bleeding. The purpose of this study was to evaluate trends of transfusion associated with knee arthroplasties using nationwide data of the National Health Insurance Service-National Sample Cohort (NHIS-NSC). Using data from the nationwide claims database of the Health Insurance Review Assessment Service managed by the NHIS, 50,553 knee arthroplasties under three categories (total knee replacement arthroplasty, uni-knee replacement arthroplasty, and revision arthroplasty) from 2012 to 2018 were identified. Overall transfusion rate, transfusion count, proportion of each type of transfusion, and cost associated with each type of operation were investigated. Overall transfusion rate was 83.4% (5897/7066) in 2012, 82.7% (5793/7001) in 2013, 79.6% (5557/6978) in 2014, 75.9% (5742/7557) in 2015, 73.1% (6095/8337) in 2016, 68.2% (4187/6139) in 2017, and 64.6% (4271/6613) in 2018. The proportion of each type of transfusion was 1.8% for fresh frozen plasma, 0.5% for platelets, and 97.7% for red blood cells. The average cost of transfusion was $109.1 ($123 in 2012, $124 in 2013, $123.3 in 2014, $110.6 in 2015, $100 in 2016, $92.9 in 2017, and $90.1 in 2018). In this nationally representative study of trends in transfusion associated with knee arthroplasty, we observed significantly high rates of blood transfusion among patients undergoing knee arthroplasties. Although the overall rate of transfusion had declined, the allogeneic transfusion rate was still high from 2012 to 2018 in Korea. Thus, surgeons need to develop various patient blood management plans and minimize the use of allogeneic transfusion when performing knee arthroplasties.