Assessing the impact of fracture pattern on transfusion requirements in hip fractures

Development and validation of machine learning models to predict perioperative transfusion risk for hip fractures in the elderly

BACKGROUND

Patients with hip fractures frequently need to receive perioperative transfusions of concentrated red blood cells due to preoperative anemia or surgical blood loss. However, the use of perioperative blood products increases the risk of adverse events, and the shortage of blood products is prompting us to minimize blood transfusion. Our study aimed to construct a machine learning algorithm predictive model to identify patients at high risk for perioperative transfusion early in hospital admission and to manage their patient blood to reduce transfusion requirements.

METHODS

This study collected patients hospitalized for hip fractures at a university hospital from May 2016 to November 2022. All patients included in the analysis were randomly divided into a training set and validation set according to 70:30. Eight machine learning algorithms, CART, GBM, KNN, LR, NNet, RF, SVM, and XGBoost, were used to construct the prediction models. The models were evaluated for discrimination, calibration, and clinical utility, and the best prediction model was selected.

RESULTS

A total of 805 patients were included in the study, of whom 306 received transfusions during the perioperative period. We screened eight features used to construct the prediction model: age, fracture time, fracture type, hemoglobin, albumin, creatinine, calcium ion, and activated partial thromboplastin time. After evaluating and comparing the performance of each of the eight models, the model constructed by the XGBoost algorithm had the best performance, with MCC values of 0.828 and 0.939 in the training and validation sets, respectively. In addition, it had good calibration and clinical utility in both the training and validation sets.

CONCLUSION

The model constructed by the XGBoost algorithm has the best performance, using this model to identify patients at high risk for transfusion early in their admission and promptly incorporating them into a patient blood management plan can help reduce the risk of transfusion.

Optimizing Orthogeriatric Hip Fracture Care: Why Fracture Type Matters

Hip fractures significantly impact morbidity and mortality among frail older adults, posing ongoing challenges in orthogeriatric care despite significant advancements. Established in the 1960s by Devas and Irvine, this field integrates orthopedics, trauma services, and geriatric medicine to address the complex needs of this population comprehensively. A critical and underexplored aspect is the precise identification and tailored treatment of various fracture types, each linked to unique clinical challenges and outcomes. This special article emphasizes the complex interplay between specific fracture types, their management options, and the roles of comorbidity and polypharmacy, highlighting the essential role of orthogeriatricians. Orthogeriatricians navigate the complexities posed by comorbidities, frailty, and polypharmacy, significantly influencing treatment outcomes. Their roles have expanded to include decision making about both operative and nonoperative strategies, emphasizing patient-centered care and moving beyond simplistic categorizations of "hip fractures." As future experts on the nuances of fracture types and their broader health implications, orthogeriatricians are also crucial in advancing treatment protocols that address preoperative and postoperative needs. Their comprehensive knowledge ensures effective in-hospital management and postdischarge planning, aligning treatment strategies with the holistic needs of frail older adults. The ongoing evolution of orthogeriatric practices promises to enhance decision-making and patient outcomes through a more informed and integrated care approach.

Intravenous tranexamic acid and thromboembolic events in hip fracture surgery: A systematic review and meta-analysis

BACKGROUND

Osteoporotic hip fractures are a major health problem in developed countries. Surgical management is the mainstay of treatment for these injuries, and historically presents an increased risk of thromboembolism, blood loss and blood transfusion. Despite the demonstrated safety of tranexamic acid (TXA) in elective hip arthroplasty, there is uncertainty regarding the risk of thromboembolism with the administration of TXA during hip fracture surgery. This study aims to address the following questions regarding patients undergoing traumatic hip fracture surgery: 1. Does intravenous TXA increase the risk of thromboembolic events? 2. Does intravenous TXA reduce peri-operative blood loss? 3. Does intravenous TXA increase the risk of non-thromboembolic complications or post-operative mortality?

METHODS

A literature search of Ovid MEDLINE, Embase, PubMed, the Cochrane Register of Controlled Trials and CINAHL was conducted, assessing results from database inception until the 11th May, 2021. We included randomised controlled trials that investigated perioperative administration of intravenous TXA in patients undergoing hip fracture surgery, compared to a control cohort. We excluded articles published in a language other than English, evaluated elective hip arthroplasty, or did not report thromboembolic events. Included trials were analysed using RevMan v5.3.

RESULTS

Sixteen articles encompassing 1491 patients met inclusion criteria. The risk difference of thromboembolic events in the TXA group was 0.02 (95%C.I. -0.01-0.04; p=0.17). TXA reduced post-operative transfusion rates by 42% (range: 28-54%, p<0.0001). The mean haemoglobin was higher in the TXA group on post-operative day one (0.77g/dL, p<0.0001), day two (0.56g/dL, p<0.0001) and day three (0.42g/dL, p<0.0001). There was no statistically significant difference in non-thromboembolic complications or post-operative mortality across the two cohorts.

DISCUSSION

There is no conclusive evidence from the current published literature that peri-operative intravenous TXA administration increases the risk of thromboembolic events after hip fracture surgery. This meta-analysis reinforces that TXA is effective in reducing post-operative transfusions and haemoglobin decline after hip fracture surgery. This study found that TXA did not increase non-thromboembolic complications or post-operative mortality. Further large-scale studies evaluating thromboembolic complications as a primary outcome are required to definitively establish the safety of TXA in hip fracture surgery.

LEVEL OF EVIDENCE

I; meta-analysis of randomised controlled trials.

Transfusion Thresholds Can Be Safely Lowered in the Hip Fracture Patient: A Consecutive Series of 1,496 Patients

INTRODUCTION

The purpose of this study is to identify optimal threshold hemoglobin (Hgb) and hematocrit (Hct) laboratory values to transfuse hip fracture patients.

METHODS

A consecutive series of hip fracture patients were reviewed for demographic, clinical, and cost data. Patients receiving an allogeneic transfusion of packed red blood cells (pRBCs) were grouped based on last Hct or Hgb (H&H) value before first transfusion. Multivariate logistic regressions of H&H quantile were performed to predict "good outcomes," a composite binary variable defined as admissions satisfying (1) no major complications, (2) length of stay below top tertile, (3) cost below median, (4) no mortality within 30 days, and (5) no readmission within 30 days. Odds ratios (OR) for "good outcomes" were calculated for each H&H quantile.

RESULTS

One thousand four hundred ninety-six hip fracture patients were identified, of which 598 (40.0%) were transfused with pRBCs. Patients first transfused at Hgb values from 7.55 to 7.85 g/dL ( P = 0.043, OR = 2.70) or Hct values from 22.7 to 23.8% ( P = 0.048, OR = 2.63) were most likely to achieve "good outcomes."

DISCUSSION

The decision to transfuse patients should be motivated by Hgb and Hct laboratory test results, given that transfusion timing relative to surgery has been shown to not affect outcomes among patients matched by trauma risk score. Surgeons should aim to transfuse hip fracture patients at Hgb levels between 7.55 g/dL and 7.85 g/dL or Hct levels between 22.7% and 23.8%. These transfusion thresholds have the potential to lower healthcare costs without compromising quality, ultimately resulting in less costly, efficacious care for the patient.

LEVEL OF EVIDENCE

Level III.

Differences between intertrochanteric and femoral neck fractures in resuscitative status and mortality rates

INTRODUCTION

Hip fracture mortality remains a challenge for orthopedic surgeons. The purpose of this study was to compare resuscitative mean arterial pressures (MAPs), intravenous fluid (IVF) administration, and mortality rates between intertrochanteric (IT) and femoral neck (FN) fracture patients.

HYPOTHESIS

We hypothesized that IT fracture patients would receive less aggressive fluid resuscitation than FNF patients given the perceived less invasive nature of intra-medullary nails compared with hemiarthroplasty.

MATERIALS AND METHODS

An institutional database was queried to identify all hip fractures managed surgically over a 2-year period. Preoperative and intraoperative MAPs and IVF administration, as measures of resuscitation, were compared between IT fracture patients treated with open reduction internal fixation and FN fracture patients treated with hemiarthroplasty.

RESULTS

Six hundred and ninety-eight hip fractures, including 531 IT and 167 FN fractures, were analyzed. There were no differences between IT and FN fracture cohorts for age, sex distribution, or Charlson Comorbidity Index scores. IT fracture patients were found to have lower MAP upon admission (103.7±20.1 vs. 107.8±18.4mmHg; p=0.026), and lower average, minimum, and maximum MAP values preoperatively and intraoperatively. Despite lower MAPs, IT fracture patients received less total IVF (581.9±472.5 vs. 832.9±496.5cc; p<0.001) and lower IVF rates intraoperatively (306.5±256.8 vs. 409.8±251.0 cc/h; p<0.001). IT fracture patients experienced higher 30-day (7.9% vs. 3.6%; p=0.040) and 90-day (10.6% vs. 5.4%; p=0.035) mortality rates and trended towards higher inpatient mortality (3.0% vs. 0.6%; p=0.088). Multivariate regression demonstrated IT pattern to be independently predictive of 30-day mortality with 2.459 increased odds relative to FN fracture (p=0.039).

DISCUSSION

IT fracture patterns are associated with decreased perioperative MAP values, yet received lower perioperative IVF rates. IT fracture patients suffered higher 30- and 90-day mortality rates, despite similar age and comorbidities.

LEVEL OF EVIDENCE

III; retrospective cohort study.

Risk factors analysis and nomogram construction for blood transfusion in elderly patients with femoral neck fractures undergoing hemiarthroplasty

INTRODUCTION

Elderly patients with femoral neck fractures (FNFs) undergoing hemiarthroplasty usually have poor physical condition. The main aim of this study was to identify risk factors for blood transfusion in these patients and construct a nomogram to intuitively predict the requirement of transfusion. The secondary purpose was to examine the relationship between blood transfusion and complications within 30 days post-operatively. Our hypothesis was that chronic kidney disease (CKD) and hypoalbuminemia may increase the requirement of transfusion.

METHODS

Data of 414 elderly patients undergoing hemiarthroplasty for FNFs were retrospectively collected. Univariate and multiple regression analysis were performed to identify independent risk factors for blood transfusion, which were used to construct a nomogram subsequently. The discrimination and calibration of the nomogram model were assessed with concordance index (C-index), the area under receiver operating characteristic curve (AUC), and calibration curve. Furthermore, the complications of blood transfusion within 30 days post-operatively were also analyzed.

RESULTS

Out of 414 patients, 127 (30.7%) received a blood transfusion. Independent risk factors for blood transfusion included CKD, hypoalbuminemia, pre-operative anaemia, general anaesthesia, higher American Society of Anesthesiologists score, more intraoperative blood loss, and longer surgical time. Increased hidden blood loss, deep vein thrombosis, superficial wound infection, and prolonged hospital stays were more common in transfused patients. The C-index of the nomogram model was 0.848 (95% CI = 0.811-0.885), and the AUC value was 0.859. The calibration curve showed a good consistency between the actual transfusion and the predicted probability.

DISCUSSION

We observed a transfusion rate of 30.7% in elderly FNF patients undergoing hemiarthroplasty. CKD and hypoalbuminemia were firstly identified as independent risk for blood transfusion. In addition, blood transfusion can increase the occurrence of early post-operative complications.

CONCLUSION

Targeted pre-operative intervention, such as optimizing CKD and correcting hypoalbuminemia is essential and highly regarded.

Safety and efficacy of a strategy of vitamin K antagonist reversal with prothrombin complex concentrates compared to vitamin K in patients with hip fracture

Background:

Increased preoperative delay in patients with hip fractures may be responsible for increased morbidity and mortality. We hypothesized that a strategy of reversal of vitamin K antagonist (VKA) by prothrombin complexes concentrates (PCCs), as compared to vitamin K, is safe and reduces preoperative delay and hospital length of stay (LOS).

Methods:

In this pilot study, we reviewed the records of patients admitted to a university-affiliated hospital for hip fracture between Jan. 1, 2012, and Dec. 31, 2016, who were taking VKA. Patients were stratified according to reversal strategy (vitamin K v. PCC). Adverse effects, time to surgery, LOS and mortality were collected from the electronic medical record and were compared between the 2 study groups and a control group not treated with VKA.

Results:

A total of 141 patients were included in the study: 65 in the vitamin K group, 26 in the PCC group and 50 in the control group. The median preoperative delay in the PCC group (20 h [interquartile range (IQR)] 13–25 h]) and the control group (20 h [IQR 15–33 h]) was lower than that in the vitamin K group (45 h [IQR 31–52 h]) (p < 0.001). Patients in the PCC group had a shorter median hospital LOS than those in the vitamin K group (6 d [IQR 4–9 d] v. 8 d [IQR 6–11 d], p < 0.05). No difference was observed in the proportion of patients who received a red blood cell transfusion, or had thrombotic or hemorrhagic complications. No difference in mortality at 12 months was observed between the groups.

Conclusion:

In patients with hip fracture, the use of PCCs as compared to vitamin K to reverse the effect of VKA significantly reduced preoperative delay and hospital LOS, and was not associated with an increase in the rates of thrombotic or hemorrhagic complications. Prospective studies involving a greater number of patients are required to confirm these promising results.

Reducing unnecessary crossmatching for hip fracture patients by accounting for preoperative hemoglobin concentration

BACKGROUND

Maximum surgical blood order schedules were designed to eliminate unnecessary preoperative crossmatching prior to surgery in order to conserve blood bank resources. Most protocols recommend type and cross of 2 red blood cell (RBC) units for patients undergoing surgery for treatment of hip fracture. Preoperative hemoglobin has been identified as the strongest predictor of inpatient transfusion, but current maximum surgical blood order schedules do not consider preoperative hemoglobin values to determine the number of RBC units to prepare prior to surgery.

AIM

To determine the preoperative hemoglobin level resulting in the optimal 2:1 crossmatch-to-transfusion (C:T) ratio in hip fracture surgery patients.

METHODS

In 2015 a patient blood management (PBM) program was implemented at our institution mandating a single unit-per-occurrence transfusion policy and a restrictive transfusion threshold of < 7 g/dL hemoglobin in asymptomatic patients and < 8 g/dL in those with refractory symptomatic anemia or history of coronary artery disease. We identified all hip fracture patients between 2013 and 2017 and compared the preoperative hemoglobin which would predict a 2:1 C:T ratio in the pre PBM and post PBM cohorts. Prediction profiling and sensitivity analysis were performed with statistical significance set at P < 0.05.

RESULTS

Four hundred and ninety-eight patients who underwent hip fracture surgery between 2013 and 2017 were identified, 291 in the post PBM cohort. Transfusion requirements in the post PBM cohort were lower (51% vs 33%, P < 0.0001) than in the pre PBM cohort. The mean RBC units transfused per patient was 1.15 in the pre PBM cohort, compared to 0.66 in the post PBM cohort (P < 0.001). The 2:1 C:T ratio (inpatient transfusion probability of 50%) was predicted by a preoperative hemoglobin of 12.3 g/dL [area under the curve (AUC) 0.78 (95% confidence interval (CI), 0.72-0.83), Sensitivity 0.66] in the pre PBM cohort and 10.7 g/dL [AUC 0.78 (95%CI, 0.73-0.83), Sensitivity 0.88] in the post PBM cohort. A 50% probability of requiring > 1 RBC unit was predicted by 11.2g/dL [AUC 0.80 (95%CI, 0.74-0.85), Sensitivity 0.87] in the pre PBM cohort and 8.7g/dL [AUC 0.78 (95%CI, 0.73-0.83), Sensitivity 0.84] in the post-PBM cohort.

CONCLUSION

The hip fracture maximum surgical blood order schedule should consider preoperative hemoglobin in determining the number of units to type and cross prior to surgery.

Establishment and assessment of a nomogram for predicting blood transfusion risk in posterior lumbar spinal fusion

Background

The aim of this study was to determine the risk factors and develop a nomogram for blood transfusions after posterior lumbar spinal fusion (PSL).

Methods

We conducted a retrospective, single-center study based on 885 patients receiving PSL, and data was obtained from May 2015 to September 2019. Univariable and multivariable logistics regression analysis were conducted to identify risk factors for blood transfusion, and a nomogram was constructed to individually evaluate the risk of blood transfusion. Discrimination, calibration, and clinical usefulness were validated by the receiver operating characteristics (ROC), C-index, calibration plot, and decision curve analysis, respectively. Bootstrapping validation was performed to assess the performance of the model.

Results

Of 885 patients, 885 were enrolled in the final study population, and 289 received blood transfusion. Statistical analyses showed that low preoperative hemoglobin (Hb), longer time to surgery, operative time, levels of fusion > 1, longer surgery duration, and higher total intraoperative blood loss (IBL) were the risk factors for transfusion. The C-index was 0.898 (95% CI 0.847–0.949) in this dataset and 0.895 in bootstrapping validation, respectively. Calibration curve showed satisfied discrimination and calibration of the nomogram. Decision curve analysis (DCA) shown that the nomogram was clinical utility.

Conclusions

In summary, we investigated the relationship between the blood transfusion requirement and predictors: levels of fusion, operative time, time to surgery, total intraoperative EBL, and preoperative Hb level. Our nomogram with a robust performance in the assessment of risk of transfusion can contribute to clinicians in making clinical decision. However, external validation is still needed in the further.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-020-02053-2.

Blood Transfusion for Elderly Patients with Hip Fracture: a Nationwide Cohort Study

BACKGROUND

This nationwide study aimed to investigate the blood transfusion status of elderly hip fracture patients and to examine the effect of packed red blood cell transfusion on all-cause mortality.

METHODS

From the Korean National Health Insurance Service-Senior cohort consisting of 588,147 participants aged over 60 years in 2002, a total of 14,744 new-onset hip fracture patients aged 65-99 years were followed up for 11 years. The adjusted hazard ratios (aHRs), risk ratios, and their 95% confidence intervals were estimated by the Cox proportional hazard model and Poisson regression model.

RESULTS

There were 10,973 patients (74.42%) in the transfusion group and 3,771 (25.58%) patients in the non-transfusion group. The mean volume of blood transfusion was 1,164.51 mL (± 865.25; median, 800 mL; interquartile range, 640-1,440). In the multivariable-adjusted Cox proportional hazard model, the transfusion group had 1.34-fold more risk of all-cause mortality than the non-transfusion group (aHR, 1.34; 95% confidence interval [CI], 1.26-1.42). In the multivariate-adjusted Poisson regression model, hip fracture patients in the transfusion group were 1.43 (adjusted risk ratio [aRR], 1.43; 95% CI, 1.09-1.87; P = 0.009) folds more likely to die within 30 days than those in the non-transfusion group. The mortality risk was highest at 90 days (aRR, 1.64; 95% CI, 1.40-1.93; P < 0.001) and slightly decreased at 180 days (aRR, 1.58; 95% CI, 1.40-1.79; P < 0.001) and 1 year (aRR, 1.43; 95% CI, 1.31-1.58; P < 0.001).

CONCLUSION

In this nationwide representative cohort study, blood transfusion was performed in 75% of hip fracture patients. Even after adjusting for comorbidity and anticoagulant use, the postoperative results (hospitalization, mortality) of the transfusion group did not show significantly worse results than the non-transfusion group. Therefore, adequate patient blood management can only improve the patient's outcome after hip fracture surgery.

Fibrin sealant reduces need for transfusions after hip hemiarthroplasty for femoral neck fractures

INTRODUCTION

Every year more than 300,000 proximal femur fractures are diagnosed. Their number will double within 30 years. In femoral neck fractures treated with hip hemiarthroplasty 90-days mortality is 29.5-51.6%. Haemorrhage is one amongst other complications that is associated with increasing postoperative mortality. Transfusion rate in these patients ranges from 25.7% to 39%. Blood transfusions expose to complications. Fibrin sealants are useful in reducing perioperative need for transfusions, total blood loss, blood loss from drainage. The aim of this study is to assess whether the use of a fibrin sealant during hip hemiarthroplasty implant reduces the need for transfusion.

PATIENT AND METHODS

All patients admitted with a proximal femur fracture from September 2018 to May 2019 were reviewed. Inclusion criteria were: femoral neck fracture AO 31B2-3, hip hemiarthroplasty. Exclusion criteria were: previous surgery on the affected hip, coagulation disorders, hematopoietic disorders. Patients were divided in fibrin sealant group and control group. All patients underwent partial hip replacement through a posterolateral approach. 4 ml of fibrin sealant (EVICEL, Omrix Biopharmaceuticals, Diegem, Belgium) were sprayed on the soft tissues of patients included in the fibrin sealant group. Primary outcome of our study was need for perioperative transfusion. Secondary outcomes were: mean red blood cell transfused volume, variations in haematocrit and haemoglobin and total blood volume loss.

RESULTS

Eighty-one consecutive patients were enrolled. EVICEL was used on 19 patients, standard haemostatic care on 62 patients. Two patients were transfused in the fibrin sealant group, 22 in the control group (p 0,0371). Mean transfused volume was 21,05 ml in the fibrin sealant group and 116,16 ml in the control group (p 0,0017). No significant difference could be found in haematocrit and haemoglobin variation and total blood loss.

DISCUSSION

A reduction in transfusional need with the use of fibrin sealants was reported in studies on total hip arthroplasty and was confirmed by our study.

CONCLUSION

EVICEL reduces need for transfusion in patients undergoing hip hemiarthroplasty for a femoral neck fracture. It must be held among the options when a stricter control on transfusional requirement is needed.

Introduction of national guidelines for restrictive blood transfusion threshold for hip fracture patients--a consecutive cohort study based on complete follow-up in national databases

Background

Randomized controlled trials have demonstrated that a restrictive red blood cell (RBC) transfusion strategy lowers transfusion frequency without affecting mortality. However, the external validity of these trials has not been tested in a large cohort. The purpose was to estimate the effect of introducing a National Clinical Guideline (NCG) for a restrictive hemoglobin transfusion threshold on transfusion frequency and mortality in hip fracture patients > 65 years old.

Methods

A consecutive cohort study of hip fracture patients > 65 years old residing in the southern region of Denmark was conducted using prospectively gathered data from registers during two separate 1-year time periods. The first period from October 1, 2012, to September 30, 2013, included 1494 patients and used a liberal transfusion threshold, whereas the second period from October 1, 2015, to September 30, 2016, including 1414 participants used a restrictive threshold from the NCG. Participant data for age, sex, body mass index, Charlson Comorbidity Index, time to surgery, and death were retrieved from the Danish Interdisciplinary Registry of Hip Fractures and were merged with RBC transfusion and medication data extracted from the Danish Transfusion and Odense Pharmacoepidemiological Databases, respectively. Cox proportional hazards models were used to test relative mortality risk for the restrictive group compared with the liberal group at 30 and 90 days.

Results

Overall RBC transfusions decreased from 42 to 30% (p < 0.001). The 30-day mortality rate (95% CI) was 9% (8;11) in the restrictive group and 13% (11;14) in the liberal group (p < 0.008), whereas the adjusted relative mortality risk was 0.72 (0.57;0.91). The 90-day mortality rate was 15% (13;17) in the restrictive group and 19% (17;21) in the liberal group, whereas the adjusted relative mortality risk was 0.78 (0.65;0.94).

Conclusion

These data suggest that the introduction of an NCG on restrictive blood transfusion leads to lower transfusion frequency in hip fracture patients > 65 years old. Even though this reduction is associated with decreased mortality at both 30 and 90 days, it may be explained by other issues than restrictive transfusion strategy. There has been an improvement in the mortality of hip fracture patients in Denmark, and we suggest that a restrictive transfusion strategy does not lead to increased mortality.