Perioperative use of blood products is associated with risk of morbidity and mortality after surgery

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.

Tranexamic acid efficacy in geriatric hip fractures: impact of nutritional status on blood loss, transfusion rates, and safety

BACKGROUND

Tranexamic acid (TXA) is a widely employed intervention in orthopedic surgeries to minimize blood loss and the need for postoperative transfusions. This study focuses on assessing the efficacy and safety of TXA specifically in undernourished older adults undergoing hip fracture procedures.

METHODS

A total of 216 patients were classified into two groups based on the Geriatric Nutritional Risk Index: undernourished and normal. In total, 82 patients received intravenous TXA at a dosage of 15 mg/kg before incision, with an additional 1 g administered intravenously over a 3-hour period postoperatively. Postoperative hemoglobin (Hb) drop, blood transfusion rate, and the incidence of deep venous thrombosis (DVT) were assessed in each group according to the presence or absence of TXA. Additionally, demographic factors including age, sex, body mass index, and serum albumin were investigated.

RESULTS

51.9% patients were identified as undernourished, experiencing progressive anemia (Hb: 10.9 ± 1.5 g/dL) and hypoalbuminemia (serum albumin: 31.9 ± 8 g/L). In comparison with the normal group, undernourished individuals were more likely to sustain femoral neck fractures (undernutrition vs. normal: 56.2 vs. 42.3%) and less likely to incur trochanteric fractures (undernutrition vs. normal: 43.8 vs. 57.7%) (P = 0.043). TXA administration significantly reduced the transfusion rate (P = 0.014) and Hb drop (P = 0.001) in the normal nutritional group, while its impact on the undernourished group remained less pronounced. There was no significant association between TXA administration and the rate of DVT complications, irrespective of the nutritional status.

CONCLUSIONS

Undernutrition not only diminishes muscle strength and gait function, leading to various types of hip fractures, but it may also hinder the efficacy of TXA in reducing blood transfusion rates and blood loss.

Complication Rates and Survival of Nonagenarians after Hip Hemiarthroplasty versus Proximal Femoral Nail Antirotation for Intertrochanteric Fractures: A 15-Year Retrospective Cohort Study of 113 Cases

OBJECTIVE

Intertrochanteric fracture is a very common but serious type of hip fracture in nonagenarians. The surgical treatment remains a significant challenge for orthopedists. The objective of this study was to investigate postoperative complications and survival outcomes compared between bipolar hemiarthroplasty (HA) and proximal femoral nail anti-rotation (PFNA) in nonagenarians with intertrochanteric fractures, and to evaluate the efficacy and safety of the two surgical procedures in this patient population.

METHODS

A total of 113 consecutive nonagenarians who underwent bipolar HA or PFNA for the treatment of intertrochanteric fractures from January 2006 to August 2021 were retrospectively studied in the current paper. There were 34 males and 79 females, with a mean age of 92.2 years (range 90-101 years) at the time of operation. The average duration of follow-up was 29.7 months (range 1-120 months). The full cohort was divided into bipolar HA (77 cases) and PFNA (36 cases) groups. Damage control orthopedics was used to determine the optimal surgery time and assist in perioperative management. A restrictive blood transfusion strategy was employed, along with appropriate adjustments under multidisciplinary assessment, throughout the perioperative period. Perioperative clinical information and prognostic data were analyzed. Kaplan-Meier survival curves were used for survival analysis, and landmark analysis divided the entire follow-up period into 1-12 months (short-term), 13-42 months (medium-term) and 43-120 months (long-term) according to the configurations of Kaplan-Meier survival curves.

RESULTS

Both groups had similar general variables except for the proportion of high adjusted Charlson comorbidity index (aCCI) (≥6 points) (6.5% in bipolar HA group and 22.2% in PFNA group, p = 0.024). Intraoperative blood loss and transfusion requirements were greater, and the intraoperative transfusion rates were higher in the bipolar HA group compared to the PFNA group (all p < 0.05). The complications rates, 1- to 60-month cumulative all-cause mortality, postoperative optimal Harris hip score (HHS), and Barthel index (BI) presented no significant difference between the two groups (all p > 0.05). Both groups had similar overall survival curves (p = 0.37). However, landmark analysis revealed that bipolar HA group exhibited higher survival rates in medium-term (p = 0.01), while similar survival rates were observed in the short- and long-term post-operation periods (both p > 0.05). Cox regression with survival-time-dependent covariate calculated the hazard ratio (HR) of bipolar HA was 0.41 in medium-term (p = 0.039).

CONCLUSION

Bipolar HA is equally effective and reliable as PFNA for treating intertrochanteric fractures in nonagenarians. Despite resulting in more intraoperative blood loss and transfusions, bipolar HA therapy is associated with a higher medium-term survival rate compared to PFNA treatment. The application of damage control orthopedics and precise perioperative patient blood management could contribute to the positive clinical outcomes observed in this patient population.

Factors Associated with Perioperative Transfusions in Veterans

Background: Private sector literature demonstrates an association between perioperative transfusions and poor clinical outcomes. Hemostatic agents, surgeon training, and patient blood management programs (PBMPs) may mitigate perioperative bleeding. This study attempts to identify preoperative risk factors associated with perioperative transfusions in Veterans. Study Design and Methods: This study is a retrospective review of the prospectively maintained Veterans Affairs Surgical Quality Improvement Project database. Included patients were older than 18 years and underwent noncardiac surgery between April 1, 2016, and March 31, 2021. Data collected included demographics, surgery variables, preoperative clinical variables, postoperative outcomes, and perioperative transfusions. Cohorts were created based on transfusion status. Univariate and multivariate analyses were performed to characterize the similarities, differences, and potential predictors of perioperative transfusion. Results: Of 6108 patients included, 153 patients received perioperative transfusions. The risks for transfusion included older age, male sex, black race, smoking, and low body mass index (BMI). The highest percent of transfused patients underwent vascular (43.4%), orthopedic (22%), and general surgeries (20%). Transfusion increased risk for postoperative cerebral vascular accident (P = .041) and 30-day mortality (P < .001). Multivariate regression analysis revealed American Society of Anesthesiology class, chemotherapy within 30 days, increased age, tobacco smoking, and decreased BMI were predictive of perioperative transfusions. Discussion: Perioperative transfusions are associated with increased morbidity and mortality in the Veteran population. These retrospective data describe the complex relationships between perioperative transfusions and outcomes after noncardiac surgery. These results serve as a foundation to create predictive models and PBMP within the veteran population to decrease transfusion requirements and associated complications.

Effects of prior antiplatelet and/or nonsteroidal anti-inflammatory drug use on mortality in patients undergoing abdominal surgery for abdominal sepsis

BACKGROUND

The effects of prior antiplatelet and/or nonsteroidal anti-inflammatory drug (NSAID) use on mortality in critically ill patients remain unclear. We investigated the relationship between antiplatelet and/or NSAID use and mortality in patients who had undergone surgery for sepsis caused by intra-abdominal infection.

METHODS

We obtained data from adult patients (aged >18 years) admitted to the intensive care unit after abdominal surgery due to intra-abdominal infection. The patients were categorized into those with and without prior antiplatelet and/or NSAID use.

RESULTS

Overall, 241 patients were enrolled, with 76 in the antiplatelet and/or NSAID use group and 165 in the non-use group. The 60-day survival probabilities for the antiplatelet and/or NSAID use and non-use groups were 85.5% and 73.3%, respectively, and this difference was significant (P = .040). In the multivariate analysis of 28-day mortality, higher Acute Physiology and Chronic Health Evaluation II score (P < .001), Simplified Acute Physiology Score III (P < .001), and blood transfusion within 5 days postoperatively (P = .034) were significant mortality risk factors. In the multivariate analysis of 60-day mortality, higher Acute Physiology and Chronic Health Evaluation II score (P = .002), Simplified Acute Physiology Score III (P < .001), and blood transfusion within 5 days postoperatively (P = .006) were also significant mortality risk factors. However, prior drug use (P = .036) was a factor in reducing mortality.

CONCLUSION

Patients with a prior history of antiplatelet and/or NSAID use had a higher 60-day survival than those who did not use these drugs. Prior antiplatelet and/or NSAID use was significantly associated with a reduction in 60-day mortality.

Patient Blood Management in Transurethral Resection Surgery: Overview and Strategy Analysis from a French Tertiary Hospital

INTRODUCTION

Since Patient blood management (PBM) suggests a bundle of measures aiming to reduce perioperative blood transfusion because preoperative anemia and blood transfusion are associated with poor postoperative outcomes. There is a lack of data on the effect of PBM in patients undergoing transurethral resection of prostate (TURP) or bladder tumor (TURBT). We aimed to assess the bleeding risk in TURP and TURBT procedures and the effect of preoperative anemia on postoperative morbimortality.

METHODS

A single-center retrospective observational cohort study was conducted in a tertiary hospital in Marseille, France. All patients undergoing TURP or TURBT were included in 2020 and divided into two groups: preoperative anemia (n = 19) and no preoperative anemia (n = 59). We recorded demographic characteristics, preoperative hemoglobin concentration, iron deficiency markers, preoperative initiation of a treatment for anemia, perioperative bleeding, and postoperative outcomes up to 30 days including blood transfusion, hospital readmission, reintervention, infection, and mortality.

RESULTS

Baseline characteristics were comparable between groups. No patient had iron deficiency markers and no prescription of iron was initiated before surgery. No major bleeding was reported during surgery. Postoperative anemia was found in 21 patients, including 16 (76%) in the preoperative anemia group and 5 (24%) in the non-preoperative anemia group. One patient of each group received a blood transfusion after surgery. No significant differences in 30-day outcomes were reported.

CONCLUSION

Our study suggests that TURP and TURBT are not associated with a high-risk of postoperative bleeding. In such procedures, adherence PBM strategies do not seem beneficial. Since recent guidelines recommend restricting preoperative testing, our results may help to improve preoperative risk stratification.

Association between isolated abnormal coagulation profile on transfusion following major surgery: A NSQIP analysis of individuals without bleeding disorders

INTRODUCTION

Preoperative coagulation screening for patients without bleeding disorders remains controversial. The combinatorial risk of INR, aPTT, and platelet count (PLT) abnormalities leading to bleeding requiring transfusion is not known in these patients. We examined the association between abnormal coagulation profile and the risk of transfusion following common elective surgery in patients without bleeding disorders.

STUDY DESIGN AND METHODS

We utilized the National Surgical Quality Improvement Program (NSQIP) database from 2004 to 2018 to identify patients without a history of bleeding disorders undergoing common 23 major elective procedures across 10 specialties. Multivariable logistic regression was used to assess the association between coagulation profile and bleeding requiring packed red blood cell transfusion intra-/post-operatively.

RESULTS

Of the 672,075 patients meeting inclusion criteria, 53.7% presented with normal coagulation profile preoperatively. Overall, 12.2% (n = 82,368) received transfusion. In the setting of normal aPTT/PLT, both Equivocal INR of 1.1-1.5 (aOR 1.41, 95% CI 1.38-1.44) and Abnormal INR of >1.5 (aOR 1.81, 95% CI 1.71-1.93) were significantly associated with an increased risk of transfusion. Equivocal (60-70) and Abnormal (>70) aPTT with normal INR/PLT did not demonstrate a comparable risk of transfusion. We observed a synergistic effect of combinatorial lab abnormalities on the risk of transfusion when both Abnormal INR/aPTT and Low PLT of <100,000 were present (aOR 5.18, 95% CI 3.04-8.84), compared to the effect of Abnormal INR/aPTT and normal/elevated PLT (aOR 1.90, 95% CI 1.48-2.45).

DISCUSSION

The preoperative presence of abnormal findings in INR or PLT was significantly associated with the risk of bleeding requiring transfusion during intraoperative and postoperative periods.

Indications and hemoglobin thresholds for red blood cell transfusion and iron replacement in adults with gastrointestinal bleeding: An algorithm proposed by gastroenterologists and patient blood management experts

Gastrointestinal (GI) bleeding is associated with considerable morbidity and mortality. Red blood cell (RBC) transfusion has long been the cornerstone of treatment for anemia due to GI bleeding. However, blood is not devoid of potential adverse effects, and it is also a precious resource, with limited supplies in blood banks. Nowadays, all patients should benefit from a patient blood management (PBM) program that aims to minimize blood loss, optimize hematopoiesis (mainly by using iron replacement therapy), maximize tolerance of anemia, and avoid unnecessary transfusions. Integration of PBM into healthcare management reduces patient mortality and morbidity and supports a restrictive RBC transfusion approach by reducing transfusion rates. The European Commission has outlined strategies to support hospitals with the implementation of PBM, but it is vital that these initiatives are translated into clinical practice. To help optimize management of anemia and iron deficiency in adults with acute or chronic GI bleeding, we developed a protocol under the auspices of the Spanish Association of Gastroenterology, in collaboration with healthcare professionals from 16 hospitals across Spain, including expert advice from different specialties involved in PBM strategies, such as internal medicine physicians, intensive care specialists, and hematologists. Recommendations include how to identify patients who have anemia (or iron deficiency) requiring oral/intravenous iron replacement therapy and/or RBC transfusion (using a restrictive approach to transfusion), and transfusing RBC units 1 unit at a time, with assessment of patients after each given unit (i.e., “don’t give two without review”). The advantages and limitations of oral versus intravenous iron and guidance on the safe and effective use of intravenous iron are also described. Implementation of a PBM strategy and clinical decision-making support, including early treatment of anemia with iron supplementation in patients with GI bleeding, may improve patient outcomes and lower hospital costs.

Evaluation of Red Blood Cell Transfusion Practice and Knowledge Among Cancer Surgeons

BACKGROUND

Transfusion of blood products has a negative impact on surgical and cancer outcomes. The objective of the current study was to evaluate surgeons' practice and knowledge of red blood cell transfusion for surgical patients.

METHODS

A survey of residents, fellows, and faculty surgeons at the Ohio State University Wexner Medical Center and surgeons who identified as taking care of cancer patients nationally was conducted. Four domains were addressed including perceived preoperative assessment and management of anemia, perceived use of transfusion alternatives, perceived use of and factors influencing packed red blood cell administration, and transfusion practice knowledge.

RESULTS

Among 158 respondents, 87 (64.5%) were surgeons on faculty at an academic medical center, 26 (19%) were surgeons in private practice, and 24 (15.2%) were surgical residents or fellows. The majority of respondents were surgical oncologists or hepatobiliary surgeons (N = 83, 62.0%) and had been in practice > 10 years (> 10-15 N = 28, 20.6%) and > 15 years N = 59, 43.4%). Only thirteen (N = 13, 8.2%) surgeons reported that they routinely complete a preoperative anemia workup. The majority of providers reported that they rarely or never use alternatives to transfusion such as erythropoietin (N = 135, 91.8%), tranexamic acid (N = 140, 94.6%), autologous blood transfusion (N = 141, 95.3%), or cell saver for benign (N = 107, 72.3%) or malignant cases (N = 133, 90.4%). Provider transfusion knowledge was variable.

CONCLUSIONS

Surgeons varied widely in their transfusion practice and knowledge. Further education of surgeons regarding transfusion medicine and practice, as well as use of transfusion alternatives, could lead to improved patient outcomes. Patient blood management programs may help inform individual surgeon practices.

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.

Cost of red blood cell transfusion; evaluation in a French academic hospital

OBJECTIVES

The economic impact of Patient blood management (PBM) must be assessed beyond the acquisition cost of blood products alone. The estimate of indirect costs may vary depending on the organization and the elements taken into account. The transposition of data from the literature into a specific local context is therefore delicate. The objective of this work was to evaluate the overall cost of red blood cell concentrate (RBC) transfusion from a French healthcare establishment point of view.

METHODS

We carried out an activity based costing analysis in our hospital for the year 2018. The steps of the transfusion process and additional costs were detailed and cumulated (resource consumption, labor time, frequency) to populate the ABC model. Several scenarios were developed focusing either on RBC, all blood products or the surgical activity, and a univariate sensitivity analysis was conducted.

RESULTS

The average total cost of transfusion, including acquisition cost, was 339,64 euros per RBC transfused. The cost of administration was 138.41 euros/RBC. Focusing only on surgical activities increased this cost (152.43 euros) while taking all blood products into account reduced it (92.49 euros).

CONCLUSION

The difference in our results with the literature confirms the local variability in the cost of transfusion, which may affect the economic impact of PBM. Our study related to the specific context of a single French institution has limitations that a multicenter study would clarify in order to carry out economic modelling of transfusion optimization and alternatives and to guide the choice of PBM strategies at the national level.

Do tourniquet and drainage influence fast track in total knee arthroplasty? Our results on 151 cases

Background: Fast track in total knee replacement (TKR) is a widely used protocol. Tranexamic acid proved to be effective in reducing perioperative bleeding without increasing thromboembolic risk. The aim of this study was to assess if tourniquet and suction drainage might affect perioperative blood loss and post-operative functional recovery after TKR. Methods: 151 patients, who underwent to TKR, were assessed and divided into three homogeneous groups: group A (51 patients) in which both tourniquet and suction drainage have been applied (tourniquet has been release before wound closure); group B (50 patients) in which neither tourniquet nor suction drainage have been used; group C (50 patients) in which only tourniquet has been used. Perioperative intravenous tranexamic acid and post-operative low-molecular-weight heparin have been administered. Trend of haemoglobin values, transfusion rate, pain, ability to obtain 90 degrees of flexion and length of stay were analysed. Results: The average intra-operative blood loss was statistically higher in group B in comparison to other two groups. Haemoglobin values were lower in group A in comparison to group C in the third and fifth post-operative days. Patients in group A had higher transfusion rate, higher pain and had more difficulties in reaching a 90 degrees of knee flexion than the other two groups. There was one infection in group A. No differences in length of stay. Conclusion: Suction drain seems to be associated to lower haemoglobin values, higher transfusion rate, higher pain and slower functional recovery. Short-term tourniquet does not influence post-operative bleeding and rehabilitation program. (www.actabiomedica.it)