Developing A Model to Predict Major Bleeding Among Hospitalized Patients Undergoing Therapeutic Plasma Exchange

Although therapeutic plasma exchange (TPE) can be associated with bleeding, there are currently no known strategies to reliably predict bleeding risk. This study developed a TPE bleeding risk prediction model for hospitalized patients. To develop the prediction model, we undertook a secondary analysis of public use files from the Recipient Epidemiology and Donor Evaluation Study-III. First, we used a literature review to identify potential predictors. Second, we used Multiple Imputation by Chained Equations to impute variables with < 30% missing data. Third, we performed a 10-fold Cross-Validated Least Absolute Shrinkage and Selection Operator to optimize variable selection. Finally, we fitted a logistic regression model. The model identified 10 unique predictors and seven interactions. Among those with the highest odds ratios (OR) were the following: > 10 TPE procedures and antiplatelet agents (OR 3.26); nephrogenic systemic sclerosis (OR 3.15); and intensive care unit stay (OR 3.08). Among those with the lowest OR were the following: albumin-only TPE (OR 0.50); male sex (OR 0.82); and heart failure (OR 0.85). The model indicated an acceptable performance with a C-statistic of 0.71 (95% CI 0.699-0.717). A model to predict bleeding risk among hospitalized patients undergoing TPE identified key predictors and interactions. Although the model achieved acceptable performance, future studies are needed to validate and operationalize it.

A Pilot Study on the Replacement of Fibrinogen with Fibrinogen Concentrates During Therapeutic Plasma Exchange with Mild to Moderate Bleeding Risk-A Comparison with Fresh Frozen Plasma and Albumin Replacement

Background: Therapeutic plasma exchange (TPE) removes coagulation factors and leads to depletion coagulopathy. The aim of the study was to compare hemostasis between TPE procedures without coagulation factor replacement (electrolyte group), the partial replacement of fibrinogen with fibrinogen concentrates (fibrinogen group) and partial coagulation factors replacement with fresh frozen plasma (partial FFP group). Methods: A total of 73 TPE procedures in patients with fibrinogen levels 1-2 g/L were divided into three study groups depending on clinically estimated bleeding risk. Standard coagulation and ROTEM® tests were performed before and after TPE. Results: Fibrinogen levels before TPE (p = 0.88) and after TPE (p = 0.33) were comparable between the fibrinogen and partial FFP groups. INR and ROTEM® parameters reflected moderately worse hemostasis after TPE with fibrinogen-only replacement compared to partial FFP replacement, which could result in increased bleeding risk. In the electrolyte group, most laboratory tests confirmed the most deranged hemostasis after TPE, as compared to fibrinogen or partial FFP replacement. A mild allergic reaction to FFP infusion was noted during one TPE. No clinically significant bleeding occurred in any of the study groups. Conclusions: Fibrinogen concentrate supplementation and partial FFP replacement can both maintain fibrinogen levels > 1 g/L after TPE, but modest differences in classical coagulation tests and bedside ROTEM® tests favor FFP replacement (NCT03801135).

Development of a Uniform Apheresis Case Report Form for Standardized Collection of Apheresis Data

Apheresis is performed worldwide for an increasing number of indications. The development of common data elements (CDE) for apheresis related areas may facilitate conduct of new research, enhance quality initiatives including benchmarking, and improve patient care. This report describes the systematic development of the Uniform Apheresis Case Report Form (UACRF) as part of the Apheresis in the United States (ApheresUS) program. A consensus panel of 17 diverse experts in apheresis, related specialties, and electronic case report form (eCRF), and database development was assembled. The panel met via online conferencing from November 17, 2020 to December 1, 2021. A draft document was posted online for public comment from October 11, 2021 to November 10, 2021. Feedback was collected using an online survey tool. The consensus panel revised the UACRF. This version was converted to an eCRF with additional changes made to improve usability in this format. The final version of the UACRF was created on August 24, 2023. The UACRF contains 16 modules: procedure and subject eligibility, patient demographics, general procedure information, laboratory parameters, vascular access, common procedure elements, eight procedure specific modules (mononuclear cell collection and seven therapeutic modalities), outcomes, and site information. A total of 137 data elements were created, including 57 with one or more subelements. The UACRF is the first systematic attempt to develop CDE for therapeutic apheresis and white blood cell collections. Further validation of the UACRF is necessary to confirm the tool's ability to collect the relevant data elements and determine the usability of the form.

Therapeutic Plasma Exchange Versus FcRn Inhibition in Autoimmune Disease

Therapeutic plasma exchange (TPE or PLEX) is used in a broad range of autoimmune diseases, with the goal of removing autoantibodies from the circulation. A newer approach for the selective removal of immunoglobulin G (IgG) antibodies is the use of therapeutic molecules targeting the neonatal Fc receptor (FcRn). FcRn regulates IgG recycling, and its inhibition results in a marked decrease in circulating autoantibodies of the IgG subtype. The difference between FcRn inhibition and PLEX is often questioned. With anti-FcRn monoclonal antibodies (mAbs) and fragments only recently entering this space, limited data are available regarding long-term efficacy and safety. However, the biology of FcRn is well understood, and mounting evidence regarding the efficacy, safety, and potential differences among compounds in development is available, allowing us to compare against nonselective plasma protein depletion methods such as PLEX. FcRn inhibitors may have distinct advantages and disadvantages over PLEX in certain scenarios. Use of PLEX is preferred over FcRn inhibition where removal of antibodies other than IgG or when concomitant repletion of missing plasma proteins is needed for therapeutic benefit. Also, FcRn targeting has not yet been studied for use in acute flares or crisis states of IgG-mediated diseases. Compared with PLEX, FcRn inhibition is associated with less invasive access requirements, more specific removal of IgG versus other immunoglobulins without a broad impact on circulating proteins, and any impacts on other therapeutic drug levels are restricted to other mAbs. In addition, the degree of IgG reduction is similar with FcRn inhibitors compared with that afforded by PLEX. Here we describe the scientific literature regarding the use of PLEX and FcRn inhibitors in autoimmune diseases and provide an expert discussion around the potential benefits of these options in varying clinical conditions and scenarios.

Therapeutic plasma exchange in hyperthyroidism prior to surgery

PURPOSE

Therapeutic plasma exchange (TPE) is a treatment option to reduce thyroid hormones in the event of contraindication or unresponsiveness to antithyroid drugs (ATDs).

METHODS

We analyzed 11 patients with hyperthyroidism who received TPE prior to surgery between January 2008 and December 2016 at our center.

RESULTS

In total, 41 processes were applied to 11 patients with hyperthyroidism. The median age was 40 years, and 90.9% of the patients were female. Seven patients had Graves' disease, while four had a toxic multinodular goiter. The distribution of TPE indications comprised contraindication to ATDs (64%) and insufficient response to ATDs (36%). An adequate response was not obtained with TPE in two patients, and cholestyramine plus methimazole and Lugol solution were applied. The median number of TPE sessions was 3. During the TPE period, a β-blocker was applied concurrently except in one patient who was contraindicated for the drug. The reduction in FT3 and FT4 hormones and the increase in TSH levels were statistically significant after TPE application (p values of 0.003, 0.033 and 0.008, respectively). Regarding adverse events of TPE application, an allergic reaction was seen in one patient, while prolongation of prothrombin time without any clinical findings was seen in another patient. Ten patients underwent total thyroidectomy, and one patient underwent a gynecological surgery procedure without any major complications.

CONCLUSION

The American Society for Apheresis guideline, which is the most referenced guideline, mentions the utilization of TPE before thyroid surgery, only in patients with thyrotoxicosis despite the wider necessity of this treatment choice under the condition of uncontrolled hyperthyroidism prior to any kind of surgery. We concluded that TPE is a reliable and effective application in patients with hyperthyroidism before any surgical procedure, according to our study results.

Plasma exchange in the intensive care unit: a narrative review

In this narrative review, we discuss the relevant issues of therapeutic plasma exchange (TPE) in critically ill patients. For many conditions, the optimal indication, device type, frequency, duration, type of replacement fluid and criteria for stopping TPE are uncertain. TPE is a potentially lifesaving but also invasive procedure with risk of adverse events and complications and requires close monitoring by experienced teams. In the intensive care unit (ICU), the indications for TPE can be divided into (1) absolute, well-established, and evidence-based, for which TPE is recognized as first-line therapy, (2) relative, for which TPE is a recognized second-line treatment (alone or combined) and (3) rescue therapy, where TPE is used with a limited or theoretical evidence base. New indications are emerging and ongoing knowledge gaps, notably regarding the use of TPE during critical illness, support the establishment of a TPE registry dedicated to intensive care medicine.

Hemostatic effects of therapeutic plasma exchange: A concise review

Therapeutic plasma exchange (TPE) alters the hemostatic balance. Contributing to TPE's hemostatic effects is the mechanical processing of blood in the extracorporeal circuit, circuit anticoagulant, type of replacement fluid, TPE schedule and number of procedures, TPE timing relative to invasive procedures, and removal of nontargeted components such as platelets, coagulation proteins, and cytokines. Although TPE's hemostatic effects are well established, how it impacts the bleeding risk is not clearly understood. In this concise review, we describe the effects of the above TPE-related factors on hemostatic balance, present data on the effects of TPE on blood hemostasis, including its effects on platelet counts and clotting assays, and review the literature on the impact of TPE-induced hemostatic changes on TPE-associated bleeding events. Finally, we discuss risk factors associated with bleeding during TPE and review the literature on TPE-associated hemostatic effects in the pediatric population.

Bleeding outcomes of inpatients receiving therapeutic plasma exchange: A propensity-matched analysis of the National Inpatient Sample

BACKGROUND

Although therapeutic plasma exchange (TPE) is associated with hemostatic abnormalities, its impact on bleeding outcomes is unknown. Therefore, the main study objective was to determine bleeding outcomes of inpatients treated with TPE.

STUDY DESIGN AND METHODS

In a cross-sectional analysis of the National Inpatient Sample (NIS), discharges were identified with 10 common TPE-treated conditions. A 1:3 propensity-matched analysis of TPE- to non-TPE-treated discharges was performed. The primary outcome was major bleeding and secondary outcomes were packed red blood cell (PRBC) transfusion, mortality, disposition, hospital length of stay (LOS), and charges. Multivariable regression analyses were used to examine the association between TPE and study outcomes.

RESULTS

The study population was 15,964 discharges, of which 3991 were TPE- treated. The prevalence of major bleeding was low (5.4%). When compared to non-TPE discharges, TPE had a significant and positive association with major bleeding (OR = 1.37, 95% CI: 1.16-1.63, p = .0003). TPE was also associated with PRBC transfusion (OR = 1.66, 95% CI: 1.42-1.94, p < .0001), in-hospital mortality (OR = 1.45, 95% CI: 1.10-1.90, p = .0008), hospital length of stay (12.45 [95% CI: 11.95-12.97] vs. 7.38 [95% CI: 7.12-7.65] days, p < .0001) and total charges, ($125,123 [95% CI: $119,220-$131,317] vs. $61,953 [95% CI: $59,391-$64,625], p < .0001), and disposition to non-self-care (OR = 1.29, 95% CI: 1.19-1.39, p < .0001).

DISCUSSION

The use of TPE in the inpatient setting is positively associated with bleeding; however, with low prevalence. Future studies should address risk factors that predispose patients to TPE-associated bleeding.

Apheresis practice patterns in the United States of America: Analysis of a market claims database

INTRODUCTION

Indications for apheresis procedures are expanding; however, the evidence for many is low quality. A better understanding of apheresis patterns in the United States is needed to better plan prospective research studies.

METHODS

Data from January 1, 2013, to September 30, 2015, were analyzed from the IBM MarketScan Research Databases of de-identified health insurance claims data of several million enrollees at all levels of care from large employers and health plans across the United States. Apheresis procedures were identified by International Classification of Diseases, Ninth version (ICD-9) and Current Procedure Terminology (CPT) codes.

RESULTS

Combining inpatients and outpatients, 18 706 patients underwent 70 247 procedures. The patients were 52.7% female, 5.1% <18 years, and 55.9% inpatient, while the procedures were 49.5% female, 5.7% <18 years, and 19.8% inpatient. For each apheresis modality, the percent of patients treated and procedures performed, respectively, are plasmapheresis 36.4% and 42.5%, autologous harvest of stem cells 22.8% and 10.7%, plateletpheresis 11.1% and 3.5%, allogeneic harvest of stem cells 8.2% and 2.5%, photopheresis 5.4% and 24.4%, erythrocytapheresis 3.8% and 4.7%, leukopheresis 2.0% and 0.7%, immunoadsorption 1.4% and 0.4%, extracorporeal selective adsorption/filtration and plasma reinfusion 1.0% and 3.6%, and other 21.6% and 6.9%. A wide variety of diagnoses were treated; however, analysis of the diagnoses suggests the procedure codes may not always reflect an apheresis procedure.

CONCLUSION

This study describes the landscape of apheresis in the United States, but may overestimate some procedures based on linked diagnosis codes. Direct measures of apheresis procedures are needed to plan future research studies.

Preoperative plasmapheresis in patients with Graves' disease intolerant to antithyroid drugs

Antithyroid drugs (ATDs) are the mainstay of treatment for Graves' disease with possible detrimental adverse effects. Surgery or radioactive iodine (RAI) ablation is the second choice among the treatment options in cases of non-remission. Normalization of serum thyroid hormone levels as much as possible is required before surgery or RAI to prevent thyrotoxic crisis in patients with uncontrolled Graves' disease. In recent decades, therapeutic plasma exchange (TPE) has been used in the treatment of thyroid storm, drug-induced hepatotoxicity and agranulocytosis, or patients with hyperthyroidism scheduled for emergency surgery. TPE is an effective method to reduce serum FT3, FT4, and TRAB levels in severe hyperthyroid conditions. Although TPE-related complications are rare, the risk of bleeding needs to be taken into consideration in patients who were scheduled for surgery within 24 h after TPE. In terms of reducing intraoperative bleeding, patients can be referred to surgery 24-48 h after TPE, or fresh frozen plasma transfusion can be the preferred treatment for emergency cases.

Liver Transplantation in Patients with Sickle Cell Disease in the United States

BACKGROUND

Up to 30% of patients with sickle cell disease (SCD) develop chronic liver disease via etiologies including sickle cell hepatopathy, acquired viral hepatitis, or secondary hemochromatosis. It is unclear how many patients with SCD ultimately undergo liver transplantation (LT) and what factors are associated with survival after LT. In this study, we examined LT outcomes in these patients by reviewing the Scientific Registry of Transplant Recipients (SRTR) and our institutional experience.

METHODS

Analysis of the SRTR identified 23 LT recipients and five simultaneous liver and kidney transplantation (SLKT) recipients with SCD. Patient demographics and graft and patient survival were analyzed. Two patients with SCD at our institution underwent SLKT.

RESULTS

Review of the SRTR revealed that recipients with SCD had significantly higher model for end-stage liver disease scores (33 versus 21, P = 0.004), preoperative intensive care unit admission (43.5% versus 19.1%, P = 0.007), preoperative dialysis (17.4% versus 4.9%, P = 0.009), and were more likely to be status 1 (26.1% versus 12.1%, P = 0.041) when compared with the reference population of African American LT recipients. Despite being higher risk at the time of LT, patients with SCD had equivalent posttransplant graft and patient survival when compared with the reference population (P = 0.5 and P = 0.2, respectively) and a 2:1 propensity score-matched group (P = 0.5 and P = 0.2, respectively). Two recent SLKT recipients with SCD from our institution have performed well with stable allograft function.

CONCLUSIONS

Data from the SRTR demonstrate that patients with SCD can expect equivalent graft and patient survival after LT despite exhibiting more comorbidities at the time of LT. The low number of patients with SCD who underwent LT in the SRTR in comparison with the rate of chronic liver disease in this population raises the question as to whether a disparity in access to LT exists for this complex population.

Preoperative plasmapheresis experience in Graves' disease patients with anti-thyroid drug-induced hepatotoxicity

Hepatotoxicity is a rare but serious side effect of antithyroid drug (ATI) therapy in Graves' disease patients. Cessation of ATI drug is needed in most of the patients if liver enzymes highly elevated or in case of agranulocytosis. Permanent therapy, surgery or radioactive iodine ablation are the treatment choices to ensure euthyroidism in active Graves' disease patients. Therapeutic plasma exchange (TPE) can be an option to ensure euthyroidism, especially in patients scheduled for urgent surgery. In the present study, we present consecutive five cases of methimazole related severe hepatotoxicity that underwent TPE before thyroid surgery. The median number of apheresis sessions was 3 (range: 2-5). Free triiodothyronine (FT3) 65-83 %, free thyroxine (FT4) 22-66 %, thyrotropin receptor antibodies (TRAB) 55-96 % decreases were observed. All patients underwent total thyroidectomy. TPE is an effective method to reduce serum FT3, FT4, TRAB levels in the short term to provide better thyroid hormone status before urgent surgery in ATI induced toxic hepatitis patients.

Visual Outcomes of Plasma Exchange Treatment of Steroid-Refractory Optic Neuritis: A Retrospective Monocentric Analysis

Introduction

In acute inflammatory optic neuritis (ON) as a typical onset of multiple sclerosis (MS), only few studies have investigated plasma exchange (PLEX) as a sequential treatment after insufficient response to high-dose intravenous glucocorticosteroids. Therefore, we aimed to investigate treatment outcome on visual acuity (VA) with PLEX in patients with steroid-refractory ON.

Methods

In our retrospective monocentric study, medical records were screened for patients with acute ON as their first relapse with sequential MS diagnosis or with an established MS diagnosis from the Bern University Hospital (Switzerland) that were treated with PLEX between 2016 and 2018 due to lacking steroid response. VA prior to steroid administration, and before and after PLEX were assessed and compared using the Friedman multiple comparison test.

Results

In total, 18 patients were included in the analysis. Interval from symptom onset to PLEX was 20.3 days (mean, 95% CI 14.8-25.9). Relevant functional improvement (VA of ≥0.5, after a mean of 15.9 (13.3-18.5) days after start of PLEX) was detected in 16/18 (88.9%) with a significant amelioration as compared to VA before glucocorticosteroids and before PLEX (p < 0.0001). VA improvement at a later time point (38.1 weeks, 25.2-51.0) was present in 15/16 (93.8%) patients. No serious adverse events were detected. PLEX could be performed via peripheral access in 13/18 patients (72.2%).

Conclusion

Our study demonstrates significant improvements of VA with PLEX in a cohort of MS patients with steroid-refractory ON. High response rates may be due to the timely treatment initiation. Despite the small sample size, our data support the early use of PLEX in steroid-refractory ON with a favorable safety profile.

Optimizing management of replacement fluids for therapeutic plasma exchange: Use of an automated mathematical model to predict post-procedure fibrinogen and antithrombin levels in high-risk patients

BACKGROUND

Therapeutic plasma exchange (TPE) utilizes an extracorporeal circuit to remove pathologic proteins causing serious illness. When processing a patient's entire blood volume through an extracorporeal circuit, proteins responsible for maintaining hemostatic system homeostasis can reach critically low levels if replacement fluid types and volumes are not carefully titrated, which may increase complications.

METHODS

The charts from 27 patients undergoing 46 TPE procedures were reviewed to evaluate the accuracy of our predictive mathematical model, utilizing the following patient information: weight, hematocrit, pre- and post-TPE factor levels (fibrinogen, n = 46, and antithrombin, n = 23), process volume and volumes of fluids (eg, plasma, albumin, and normal saline) administered during TPE and adverse events during and after TPE.

RESULTS

Altogether, 25% of patients experienced minor adverse events that resolved spontaneously or with management. There were no bleeding or thrombotic complications. The mean difference between predicted and measured post-TPE fibrinogen concentrations was -0.29 mg/dL (SD ±23.0, range -59 to 37), while percent difference between measured and predicted fibrinogen concentration was 0.94% (SD ±10.8, range of -22 to 19). The mean difference between predicted and measured post-TPE antithrombin concentrations were 0.89% activity (SD ±10.0, range -23 to 14), while mean percent difference between predicted and measured antithrombin concentrations was 3.87% (SD ±14.5, range -25 to 38).

CONCLUSIONS

Our model reliably predicts post-TPE fibrinogen and antithrombin concentrations, and may help optimize patient management and attenuate complications.

Plasma exchange in catastrophic antiphospholipid syndrome

Plasma exchange is a well-established therapeutic procedure commonly used in many autoimmune disorders. The beneficial effects of plasma exchange are thought to occur through the elimination of pathogenic mediators found in plasma, including autoantibodies, complement components, and cytokines. The catastrophic antiphsopholipid syndrome (CAPS) is a life-threatening variant of the antiphospholipid syndrome (APS) where several thrombosis take place in a short period of time in patients with circulating antiphospholipid antibodies. The triple therapy with anticoagulation, corticosteroids and plasma exchange or intravenous immunoglobulins has been proposed in CAPS. CAPS is a rare disease precluding the conduction of formal clinical trials. However, the observation of a better clinical course of patients who received this treatment supports their use. Plasma exchange has become an established therapeutic procedure in CAPS but there are no studies regarding the better approach and thus its use relies on the experience of the physicians in charge. The current article aims to review potential mechanisms of action of plasma exchange and the technical aspects of this procedure and will focus on its current role in CAPS, the experience published in treating this condition and the treatment protocol that we use in our institution.