A randomized crossover study comparing membrane and centrifugal therapeutic plasma exchange procedures

HemoClear: A Practical and Cost-Effective Alternative to Conventional Convalescent Plasma Retrieval Methods

Convalescent plasma has increasingly been used to treat various viral infections and confer post-exposure prophylactic protection during the last decade and has demonstrated favorable clinical outcomes in patients infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) during the recent COVID-19 pandemic. The pandemic has highlighted the need for cost-effective, accessible, and easy-to-use alternatives to conventional blood plasmapheresis techniques, allowing hospitals to become more self-sufficient in harvesting and transfusing donor plasma into recipients in a single setting. To this end, the use of a membrane-based bedside plasmapheresis device (HemoClear) was evaluated in an open-label, non-randomized prospective trial in Suriname in 2021, demonstrating its practicality and efficacy in a low-to middle-income country. This paper will review the use of this method and its potential to expedite the process of obtaining convalescent plasma, especially during pandemics and in resource-constrained settings.

Feasibility, Efficacy, and Safety of Peripheral Venous Access for Chronic Double-Filtration Plasmapheresis with Regional Citrate Anticoagulation

INTRODUCTION

Peripheral venous access (PVA) is recommended as a first-line vascular approach for therapeutic plasmapheresis with centrifugation methods but not filtration, which usually requires high blood flow. We evaluated the feasibility, efficacy, and safety of double-filtration plasmapheresis (DFPP) with PVA, using ultrasound guidance and regional citrate anticoagulation (RCA), i.e., PVA-RCA-DFPP in patients undergoing chronic DFPP. Secondly, we assessed the number of central venous catheters (CVCs) avoided.

METHODS

A single-center retrospective study evaluated 22 adult patients on chronic DFPP to perform PVA-RCA-DFPP. They were classified into 3 groups: successful (i.e., completion of sessions with PVA), primary failure (i.e., no sessions completed), secondary failure (i.e., ≥1 session with PVA completed but secondary return with CVC or arteriovenous fistula).

RESULTS

Among the 22 patients included (64% men), 7 patients (32%) were classified as primary failures (2 patient refusals, 5 inadequate PVAs), 1 patient (5%) as a secondary failure (due to uncomfortable venipunctures), and 14 patients (64%) as successful. In the successful group including 12 patients treated for chronic inflammatory demyelinating polyneuropathy (CIDP) and 2 patients for familial hypercholesterolemia (FH) (2 patients), 116 sessions were performed, with a median treated plasma volume of 4.3 L [IQR 3.6-4.6] (45 mL/kg) for a median duration of 134 min [IQR 122-144], and a median blood flow of 94 mL/min [IQR 87-103]. For the CIDP group, 90% of sessions achieved a plasma volume >1 TPV, and for the FH group 91% of sessions achieved an LDLc reduction >60%. Eleven sessions out of 116 (9%) were interrupted, mostly due to PVA dysfunction (5/11) and circuit clotting (4/11). Session interruptions decreased significantly between each patient's first and following sessions (29% to 7%, p = 0.009).

CONCLUSION

Chronic PVA-RCA-DFPP can be performed safely and efficiently, avoiding the use of CVCs.

Survival Benefits of Therapeutic Plasma Exchane in Severe Sepsis and Septic Shock: A Systematic Review and Meta-analysis

OBJECTIVES

To summarize the role of therapeutic plasma exchange (TPE) in critically ill adults and children with severe sepsis.

DATA COLLECTION

A systematic search was performed using the following databases: Medline, EMBASE, CINAHL, and Cochrane from January 1990 till December 2022. Comparative studies of TPE in severe sepsis were selected. Adult and pediatric data were analyzed separately.

DATA SYNTHESIS

Eight randomized control trials and 6 observational studies (n = 50,142 patients) were included. Centrifugal TPE was the most common modality (209/280, 74.6% adults and 952/1026, 92.7% children). Every TPE study utilized different volume exchanges. Most TPE sessions (1173/1306, 89.8%) employed fresh frozen plasma (FFP) as replacement fluid and heparin as anticoagulant. Adults with severe sepsis supported with TPE using FFP had lower mortality (risk ratio, RR: 0.64 [95% confidence interval, CI: 0.49, 0.84]) compared to those who did not. In contrast, TPE was associated with increased mortality in septic children without thrombocytopenia-associated multiorgan failure (RR: 2.23, 95% CI: 1.93, 2.57). There was no difference in outcomes in patients supported with centrifugal and membrane TPE. In both populations, patients supported on TPE as a continuous regime had poorer outcome.

CONCLUSION

Current evidence indicates that TPE is a potential adjunct therapy in adults with severe sepsis but not in children.

Comparison of plasma separation using centrifugation or filtration for MONET lipoprotein apheresis in patients with cardiovascular disease and severe dyslipidemia

INTRODUCTION

Homozygous or severe heterozygous familial hypercholesterolemia and elevated lipoprotein(a) levels may be treated with membrane filtration. The MONET system (Fresenius Medical Care, Bad Homburg, Germany) involves plasma separation by centrifugation or filtration.

METHODS

Whether the method of plasma separation affects lipoprotein lowering and treatment safety was investigated in a single-center retrospective study.

RESULTS

The centrifugation-based plasma separation achieved a higher plasma flow and shorter time to treat 1 L of plasma (46.2 ± 8.6 min), than the filtration-based system (71.5 ± 40.0 min; p = 0.001). The mean reduction of LDL-cholesterol was 69% and 67% with centrifugation and filtration and was 75% for lipoprotein(a) with both plasma separation methods. A reduction of IgM by more than 60%, of albumin and total protein by approximately 20% and low frequency of side effects was observed.

CONCLUSIONS

The efficacy of lowering atherogenic lipoproteins was comparable with both plasma separation methods. Centrifugation was more time-efficient compared to filtration.

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.

Centrifugal therapeutic plasma exchange in dogs with immune-mediated hemolytic anemia (2016-2018): 7 cases

OBJECTIVE

To describe the technique of centrifugal therapeutic plasma exchange (cTPE) in dogs diagnosed with immune-mediated hemolytic anemia (IMHA) and summarize the outcome of the procedure.

DESIGN

Retrospective review of cTPE performed at North Carolina State University from 2016 to 2018, through a search of the institutional database for cTPE and IMHA.

SETTING

University teaching hospital.

ANIMALS

Seven dogs with confirmed IMHA were presented to a university teaching hospital ICU for cTPE. Six dogs were not responsive to standard medical management with immunosuppressive agents, while 1 dog presented before immunosuppressive agents were begun.

INTERVENTIONS

All dogs underwent multiple cTPE procedures using 1 of 2 commercially available apheresis systems.

MEASUREMENTS AND MAIN RESULTS

At presentation, the median HCT was 0.15 L/L (15.7%) (range, 0.10-0.19 L/L [10.3%-19%]) and the median total serum bilirubin was 32.5 mmol/L (1.9 mg/dl) (range, 15.4-597 mmol/L [0.9-34.9 mg/dl]). The median number of transfusions before cTPE was 1 (range, 1-4), with a median total of infused RBCs of 12.9 ml/kg (range, 8.8-37 ml/kg). cTPE with an exchange of ≥4 times total plasma volumes was used to decrease the level of circulating autoreactive antibodies. The median total plasma volumes exchanged was 4.5 times (range, 2.5-6.5 times) over 2-4 procedures. Anticoagulation was performed using a combination of systemic heparinization and regional citrate in all dogs. Six of 7 dogs (85.7%) were discharged from the hospital and were alive 90 days after discharge. One dog (14%) did not respond to cTPE (∼6.5 times total plasma volume exchanged) and was euthanized.

CONCLUSIONS

cTPE is a feasible and relatively safe bridging treatment option for the management of canine IMHA.

Comparison of centrifugal and membrane filtration modalities on therapeutic plasma exchange

BACKGROUND

Therapeutic plasma exchange (TPE) is a technique in which plasma is separated from the rest of the blood in an extracorporeal system and exchanged with appropriate fluids. Two main methods are used in the TPE process: membrane filtration (mTPE) and centrifuge-based (cTPE) TPE. We aimed to compare the efficacy of these methods and their effects on hemostatic parameters.

METHODS

A total of 88 TPE procedures performed on 51 patients were evaluated retrospectively. Hemostatic parameters, such as pre- and postoperative complete blood count, fibrinogen, and D-dimer levels were evaluated, as well as data recorded during the TPE application, such as preparation time, operation time, and plasma removal efficiency (PRE). The Fresenius multiFiltrate, software version 5.3 device was used for the mTPE procedure and the Spectra Optia device was used for cTPE.

RESULTS

While both modalities removed similar amounts of plasma, the total time to perform the cTPE treatment was significantly lower than the mTPE (107 [66-191] min vs 116.5 [80-181] min, respectively) (P = .026). At the PRE rate, the mTPE procedure was as effective as cTPE (86.8% ± 16.3 vs 85.15% ± 17.63 respectively, P = .64). The difference was not statistically significant, and this is the highest rate of PRE reported about the mTPE procedure in the literature.

CONCLUSIONS

To our knowledge, this is the first study directly comparing Fresenius and Spectra regarding mTPE and cTPE. While there were no statistically significant differences regarding PRE, treatment time of the mTPE was significantly longer than the cTPE treatment time.

Plasma Exchange in Acute and Acute on Chronic Liver Failure

Liver failure in the context of acute (ALF) and acute on chronic liver failure (ACLF) is associated with high mortality in the absence of a liver transplant. For decades, therapeutic plasma exchange (TPE) is performed for the management of immune-mediated diseases. TPE has emerged as an attractive extracorporeal blood purification technique in patients with ALF and ACLF. The basic premise of using TPE is to remove the toxic substances which would allow recovery of native liver functions by facilitating liver regeneration. In recent years, encouraging data have emerged, suggesting the benefits of TPE in patients with liver failure. TPE has emerged as an attractive liver support device for the failing liver until liver transplantation or clinical recovery. The data in patients with ALF suggest routine use of high-volume TPE, while the data for such a strategy are less robust for patients with ACLF.

Comparison of three modalities of plasmapheresis on coagulation: Centrifugal, single-membrane filtration, and double-filtration plasmapheresis

BACKGROUND

Plasmapheresis can deplete pathogenic antibodies and allow ABO- and/or HLA-incompatible transplantation.

AIM

To determine the impacts of three modalities of plasmapheresis (centrifugal plasmapheresis [cTPE], single-filtration plasmapheresis [mTPE], double-filtration plasmapheresis [DFPP]) on hemostasis parameters and thrombin generation.

MATERIALS/METHODS

Prospective, comparative study on 21 patients that received three modalities of plasmapheresis (7 patients/group). Hemostasis (prothrombin time [PT], activated partial thromboplastin time [aPTT], procoagulant factors and natural anticoagulants) were measured before and after the first plasmapheresis session. Thrombin generation was also assessed in platelet-poor plasma using an STA-Genesia (Stago) analyzer and Thromboscreen reagents (Stago) in 4-5 patients from each group.

RESULTS

Both cTPE and mTPE resulted in high decreases in proteins, whatever their molecular weights. Median post/pre ratios were 0.27 to 0.55 for cTPE for most proteins (except FVIII [0.64] and VWF [0.57]). Median post/pre-ratios of mTPE were 0.28 to 0.56 for all proteins. DFPP decreased high-molecular-weight proteins (fibrinogen, FV, FVIII, FXI, VWF) and proteins strongly bound to large molecules (protein SandTFPI). Median post/pre ratios with cTPE and mTPE were similar to DFPP for fibrinogen and FXIII. Regarding thrombin generation, cTPE and mTPE did not significantly modify endogenous thrombin potential (ETP) and DFPP induced a slight decrease in ETP (median post/pre ratio at 0.73) in the absence of thrombomodulin. ETP inhibition by thrombomodulin was decreased for all procedures.

CONCLUSIONS

DFPP depleted high molecular-weight proteins in contrast to cTPE and mTPE, which significantly decreased all proteins. Regarding thrombin generation, depletion of procoagulant factors was counterbalanced by a decrease in some natural anticoagulants whatever plasmapheresis method used; with all methods, fibrinogen and FXIII were highly depleted.

Peripheral vascular access for therapeutic plasma exchange: A practical approach to increased utilization and selecting the most appropriate vascular access

BACKGROUND

Therapeutic plasma exchange (TPE) is used in the treatment of many diseases. At present, peripheral vascular access (PVA) is an underutilized method of vascular access in TPE. It should be considered more frequently due its relatively low risk for adverse events, particularly infections.

METHODS

The Advancing Vascular Access in Apheresis Working Group met in December 2017 for an extensive review and discussion of vascular access for TPE and developed a "road map" providing detailed information regarding clinical situations in which PVA-based TPE would and would not be appropriate.

RESULTS

The road map is consistent with current recommendations that PVA should be used in combination with TPE whenever possible. PVA should be considered for patients who do not have existing central lines and who are stable. The patient should have peripheral veins that will allow for adequate treatment and must be able to comply with the process of achieving and maintaining peripheral access. There should be expert clinical assessment of veins, and this evaluation may include ultrasound and/or near infrared evaluation. Conditions that would prompt a switch from PVA to an alternate method of venous access include loss of venous access, patient preference, or development of a requirement for very frequent treatment over a long period of time.

CONCLUSIONS

While PVA is not suitable for all patients requiring TPE, it has significant safety advantages over other approaches and should be employed whenever possible.

Therapeutic plasma exchange (TPE) for semi-critical neurology presentations in a non-acute neurology set-up: clinical practice and challenges

Introduction

Therapeutic plasma exchange (TPE) for semi-critical neurological manifestations can be managed in non-acute setting instead of critical care unit. In 2014, we established a non-acute neurology TPE unit for semi-critical haemodynamically stable patients. In this study, we aimed to evaluate the technical and safety parameters from the first 3 years of service.

Materials and methods

We analysed prospectively collected TPE data for patients treated with centrifugation TPE at our non-acute neurology TPE unit in Kuala Lumpur Hospital between May 2015 and June 2018.

Results

A total of 245 TPE procedures were performed in 55 patients for nine neurological indications, predominantly the central nervous system (79%). Twenty four per cent (n=13) had category I and 73% (n=40) had category II indication (American Society for Apheresis (ASFA) 2019). Others (4%) were not in ASFA indications. Neuromyelitis optica spectrum disorders accounted for half (51%) of the total patients. Twenty-three (41.8%) patients experienced adverse events, with hypotensive episodes being the the most common (n=12/55, 21.8%). Five (9.1%) patients had catheter-related blood stream infection, correlating with higher exchange plasma volume (p=0.023). Symptomatic hypocalcaemia was less common (n=5/55, 9.1%) and allergic reaction to human albumin was rare (n=1/55, 1.8%). Four technical errors detected. Three involved centrifugation sets manufacturing defects and one involved error in centrifugation set installation. Seven (2.9%) procedures were terminated: 5 for adverse effects and 2 for technical errors.

Conclusion

Performing TPE among semi-critical patients with neurology manifestations in basic non-acute set-up proved safe, with predictable complications. This set-up reduced the reliance on critical care services for TPE procedures.

The establishment of in-house neurology driven therapeutic plasma exchange infrastructure in a resource-limited public hospital in Malaysia: Adopting and integrating evidenced-based health care technology through time

There has been an increase in the use of therapeutic plasma exchange (TPE) in immune-mediated neurological disorders in recent years. However, accessibility and availability of TPE remains low and costly, especially for a country with limited healthcare funding like Malaysia. With expanding clinical indications in neurological disorders, and increasingly expensive conventional immunomodulatory treatment such as intravenous immunoglobulin and monoclonal antibodies, TPE remains an effective part of first or second-line treatment. In this article, we detailed the historical aspects of the use of TPE in neurological disorders in Malaysia over the last four decades and discussed the challenges behind the establishment of the first in-house neurology-driven TPE service in the country. Local TPE database from a national neurology centre in Kuala Lumpur over the past 20 years was analyzed. We observed a remarkable three folds increase in the use of TPE at our center over the past 10 years (total 131 TPE treatments) compared to a decade prior, with expanding clinical indications predominantly for central nervous system demyelinating disorders. Besides using membrane filtration method, centrifugal technique was adopted, providing new opportunities for other clinical beneficiaries such as a neurologist driven "in-house TPE unit". However, there were real world challenges, especially having to provide services with limited funding, human resources, and space. In addition, much has to be done to improve accessibility, availability, and sustainability of TPE services at our center and nationwide. Nevertheless, even with limited resources and support, it is possible with concerted efforts to work within the confines of these limitations to establish a safe, successful, and sustainable TPE service.

Therapeutic plasma exchange: Experience in a third level hospital, 2013-2016, Lima (Peru)

BACKGROUND

Therapeutic plasma exchange (TPE) is an extracorporeal procedure which consists of removing the patient's plasma and replacing it with an appropriate replacement fluid. Plasma and blood cells are separated by a centrifugation process. Our department has used TPE for several years, and in 2013 we introduced an institutional apheresis protocol. The main objective of this report is to describe the TPE procedures performed between 2013 and 2016 in the Peruvian population.

METHODS

We analyzed the technical and clinical aspects of 864 centrifugal TPE procedures as well as the associated complications. We evaluated 230 patients treated in our institution.

RESULTS

The therapeutic indications included 16 different diseases: 89.5% (N = 206/230) neurological, 7.3% (N = 17/230) hematological, 1.7% (N = 4/230) rheumatologic, 0.8% (N = 2/230) dermatological and 0.4% (N = 1/230) nephrological. 70.4% (N = 142/230) of patients were diagnosed with Guillain-Barré syndrome. Albumin 5% solution was the most frequent replacement solution, used in 65.8% (N = 569/864) of the procedures. The mean plasma volume (PV) replaced was 2451.73 ml, corresponding to 1.0 PV in all procedures. Complications occurred in 10.9% (N = 95/864) of the sessions. Allergic reactions were the most common events and cardiopulmonary arrests were recorded in two patients.

CONCLUSION

This is the first report of TPE performed in the Peruvian population. The use of an institutional apheresis protocol was beneficial to improve registries in our service and our professional health attention. This study reports a low rate of complications, suggesting that TPE is safe. There is a need to create a multicenter Peruvian apheresis registry to assess the benefits and risks of TPE in Peru.

Therapeutic plasma exchange in a tertiary care center: 185 patients undergoing 912 treatments - a one-year retrospective analysis

BACKGROUND

Therapeutic plasma exchange (TPE) is increasingly used throughout the world. Although the procedure itself is fairly standardized, it is yet unknown how the underlying disease entities influence the key coordinates of the treatment.

METHODS

Retrospective chart review. The treatment indications were clustered into four categories. Data are presented as median and interquartile (25-75%) range [IQR].

RESULTS

Within 1 year, 912 TPE treatments were performed in 185 patients (90 female, 48.6%). The distribution of the treatment numbers to the pre-specified disease categories were as follows: transplantation (35.7%), neurology (31.9%), vasculitis and immunological disease (17.3%), and others including thrombotic microangiopathy (8.1%), critical care related diseases (5.4%), hematology [multiple myeloma] (1.1%), and endocrine disorders (0.5%). The calculated plasma volume was significantly higher in patients with vasculitis and immunological diseases (3984 [3433-4439] ml) as compared to patients treated for transplant related indications (3194 [2545-3658] ml; p = 0.0003) and neurological diseases (3058 [2533-3359] ml; p < 0.0001). This was mainly due to the differences in the hematocrit which was 30.5 [27.0-33.6] % in the vasculitis/immunological disease patients and 40.2 [37.5-42.9] % in the neurological patients; p < 0.0001. Interestingly, treatment time using a membrane based technology was significantly longer than TPE using a centrifugal device 135.0 [125.0-140.0] min vs. 120.0 [112.5-135.0] min. Furthermore, the relative exchanged plasma volume was significantly lower in the treatment of vasculitis and immunological diseases as compared to treatments of transplant related indications and neurological diseases.

CONCLUSION

Patients with low hematocrit and high body weight do not receive the minimum recommended dose of exchange volume. Centrifugal TPE allowed faster plasma exchange than membrane TPE.