Effect of therapeutic plasma exchange on plasma levels and total removal of adipokines and inflammatory markers

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.

Attenuation of age-elevated blood factors by repositioning plasmapheresis: A novel perspective and approach

Aging is associated with the impairment of stem cell activation, leading to the functional decline of tissues and increasing the risk for age-associated diseases. The old, damaged or unrepaired tissues disturb distant tissue homeostasis by secreting factors into the circulation, which may not only serve as biomarkers for specific age-associated pathologies but also induce a variety of degenerative phenotypes. In this review, we summarize and discuss systemic determinants that perpetuate age-related tissue dysfunction. We further elaborate on the effects of attenuating these circulating factors by highlighting recent advances which utilize plasmapheresis in a pre-clinical or clinical setting. Overall, we postulate that repositioning therapeutic plasma exchange (TPE) to dilute the systemic factors, which become deleterious at their age-elevated levels, could be a rapidly effective rejuvenation therapy that recalibrates crucial signaling pathways to a youthful state.

Pro: High dose of therapeutic plasma exchange-mind the gap!

'Mind the gap' is a recorded warning phrase used in the London Tube since 1969. The following article is meant to be a warning of an increasing knowing-doing gap in routine practice of therapeutic plasma exchange (TPE), a treatment method that is used more and more throughout the world. The American Society of Apheresis recommendations, including the most recent ones from 2016, suggest using a TPE volume of 1.0-1.5 times the actual calculated plasma volume of the patient. There are only a few exceptions to that rule, such as the recommnded exchange volume in vasculitis or mushroom poisoning. The published literature suggests that in routine clinical practice in many institutions in several countries the exchanged volume might in fact be lower than recommended by the guidelines. In the following article we argue for a high dose of exchanged plasma volume, yet sketch different scenarios on how this time-averaged high dose can be delivered in various ways depending on the underlying disease, refuting a one-size-fits-all strategy that might facilitate the procedure but may result in 'underpheresis' in many patients. Further, the objectives underlying the use of smaller exchange volumes, especially the gap between the cost of blood products and the reimbursement of TPE are discussed. Lastly, the knowing-guiding gap is described, which can only be overcome by collecting high-quality data and conducting prospective clinical trials in the field of TPE.

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.

[Role of plasmapheresis and immunoadsorption in salvage therapy of rheumatological diseases]

Many rheumatological diseases are either caused by specific known proteins, such as antibodies or mediated by a plethora of cytokines. Both the unspecific immunosuppressive therapy and the specific action of biologics usually require time to be effective; therefore, extracorporeal forms of treatment are increasingly being employed in severe forms of rheumatological diseases as well as in patients who cannot tolerate pharmacological treatment or where the risk of pharmacological treatment may outweigh the potential benefits. Therapeutic plasma exchange (TPE) removes not only pathogenic substances, such as autoantibodies, lipoproteins and circulating immune complexes from the plasma but also cytokines. The removed plasma that is discarded has to be substituted by blood products, e.g. human albumin or fresh frozen plasma. Fresh frozen plasma is always used when missing plasma components must be replenished, such as ADAMTS-13 in thrombotic thrombocytopenic purpura (TTP). The separated plasma can be further processed by pumping into a hollow fiber filter (cut-off of ~700 kD) and in this way low-density lipoprotein cholesterol and IgM can be eliminated. This treatment mode, called cascade filtration is used to treat diseases, such as Waldenström's macroglobulinemia and cryoglobulinemia. A specific way to remove antibodies is by immunoadsorption in which the antibodies are specifically removed by an adsorber. For this procedure there is no need to substitute blood products. This review article describes the principles of the two different treatment methods, the advantages and disadvantages and also summarizes the current evidence for their use in rheumatological diseases.

Membrane versus centrifuge-based therapeutic plasma exchange: a randomized prospective crossover study

BACKGROUND

Therapeutic plasma exchange (TPE) is either performed using a highly permeable filter with standard multifunctional renal replacement equipment (mTPE) or a centrifugation device (cTPE). Although both techniques are well established in clinical practice, performance of these two modes of TPE was never compared in a prospective randomized fashion. Thus we aimed to compare two commercially available therapeutic apheresis systems: mTPE (Octonova with Plasmaflo filter) and cTPE (Spectra Optia apheresis system).

METHODS

Twenty-one patients (age 51.6 ± 13.5 years; 10 F/11 M; BMI 25.1 ± 5.0 kg/m(2)) were enrolled in this randomized, prospective, paired, crossover study performed in the Hannover Medical School, Germany. First treatment (either mTPE or cTPE) was chosen by an online randomization list. The primary endpoints were plasma removal efficiency with 1.2× of the total plasma volume exchanged. Secondary endpoints were total amount of plasma substances removed, such as IgG and fibrinogen. Further, the treatment effect on platelet count and complications were evaluated.

RESULTS

Despite a comparable volume of the processed plasma, mTPE treatment time was 10.5 % longer than cTPE treatment time (p < 0.05), resulting in a 10 % lower plasma removal rate of the mTPE treatment. Both treatments were comparable in terms of decrease in median (IQR) IgG [pre-mTPE 5.34 (3.48-8.37), post-mTPE 1.96 (1.43-2.84) g/L; pre-cTPE 5.88 (3.42-8.84), post-cTPE 1.89 (1.21-3.52) g/L]. Also the median (IQR) amount of IgG removed in mTPE [13.14 (7.42-16.10) g] was not different from the cTPE treatment [9.30 (6.26-15.69) g]. This was also true for IgM removal. Platelet loss during mTPE was nearly twice as much as with cTPE (15 ± 9 versus 7 ± 9 %, p < 0.05).

CONCLUSION

Although the centrifugal procedures were conducted using flow rates that could easily be obtained using peripheral access, plasma removal efficiency was significantly higher and treatment time was significantly lower in cTPE as compared to mTPE. Despite this lower treatment time, the decline in markers of procedure efficacy was comparable. Especially in centers performing many procedures per year, cTPE in contrast to mTPE can reduce treatment time without compromising treatment efficacy.