Clearance of fibrinogen and von Willebrand factor in serial double-filtration plasmapheresis

The effects of double-filtration plasmapheresis on coagulation profiles and the risk of bleeding

BACKGROUND/PURPOSE

Double-filtration plasmapheresis (DFPP) can be used to remove circulating pathogenic molecules. By reclaiming filtered albumin, DFPP reduces the need for albumin and plasma replacement. Large proteins, such as fibrinogen, are removed. Our institution adopts a DFPP treatment protocol consisting of active surveillance of coagulation profiles and prophylactic supplementation of blood products containing fibrinogen. This study aims to investigate the effects of consecutive DFPP treatments on serial coagulation profiles and the risk of bleeding under this protocol.

METHODS

Serial laboratory data and bleeding events at a single tertiary medical center were prospectively collected. Prophylactic transfusion of cryoprecipitate or fresh frozen plasma (FFP) was instituted if significant coagulopathy or a clinically evident bleeding event was observed.

RESULTS

After the first treatment session, plasma fibrinogen levels decreased from 332 ± 106 mg/dL to 96 ± 44 mg/dL in the 37 study patients. In the following sessions, plasma fibrinogen levels were maintained at around 100 mg/dL under prophylactic transfusion. No major bleeding events were recorded, but five (14%) patients experienced minor bleeding.

CONCLUSION

DFPP treatment might be performed safely along with active monitoring of coagulation profiles and prophylactic transfusion of cryoprecipitate or FFP.

Physiological role of plasma and its components and the clinical implications of different methods of apheresis: A narrative review

Nowadays, therapeutic plasmapheresis (TP) is accepted as part of the treatment for specific groups of diseases. The availability of different methods, including double filtration and adsorption, increases selectivity for the removal of substances. However, the use of these techniques requires a thorough understanding of the characteristics and components of plasma. By considering pivotal papers from several databases, the aim of this narrative review is to describe the characteristics of plasma related to apheresis techniques. We have tried to cover the clinical implications including physiology, estimation of plasma volume, viscosity, and a description of its components including the size, volume of distribution, and half-lives of the different substances to be removed or maintained depending on the clinical situation and applied apheresis technique. Applying this knowledge will help us to choose the right method and dosage and improve the efficacy of the procedure by preventing or addressing any complications.

Effect of Double Filtration Plasmapheresis on Various Plasma Components and Patient Safety: A Prospective Observational Cohort Study

Double filtration plasmapheresis (DFPP) was historically used for blood group incompatible renal transplantation. Very few studies are available worldwide regarding its efficiency in removing specific plasma components, and safety. We conducted a prospective observational cohort study over 1 year on patients undergoing DFPP for various renal indications. There were 15 patients with 39 sessions. The pre- and post-procedure plasma samples of serum IgG, IgA, IgM, fibrinogen, calcium, phosphate, potassium, and magnesium were analyzed. The effluent albumin concentration was also measured, and complications during the hospital stay were recorded. Cumulative removal of serum IgG, IgA, IgM, fibrinogen, and albumin at the end of four sessions were 72%, 89%, 96%, 88.5%, and 21.3%, respectively and effluent albumin concentration was 1.75 – 2.0 times (range: 6.3 g/dl – 7.2 g/dl; mean ± standard deviation (SD) – 7 g/dl ± 0.3 g/dl) the preprocedural serum albumin (mean ± SD – 3.5 g/dl ± 0.5 g/dl). Removal of other plasma components were not statistically significant. Hypotensive episodes were observed only 16.6%, with the usage of effluent concentration albumin as replacement fluid despite an average 2.4 (mean ± SD – 2.4 ± 0.4 l) liters of plasma volume processing each session. DFPP removes IgG, IgA, IgM, fibrinogen, and albumin. The cumulative removal IgG (72%) is suboptimal, whereas IgA (89%) and IgM (96%) are comparable to historical controls. We observed lesser episodes (12.5%) of hypotension with effluent albumin concentration as replacement fluid, and all bleeding complications were observed when serum fibrinogen level was <50 mg/dl.

Plasma von Willebrand factor levels predict in-hospital survival in patients with acute-on-chronic liver failure

BACKGROUND AND AIMS

Circulating levels of von Willebrand factor (vWF) predict mortality in patients with cirrhosis. We hypothesized that systemic inflammation in acute-on-chronic liver failure (ACLF) will stimulate endothelium, increase vWF levels, and promote platelet microthrombi causing organ failure.

METHODS

In this prospective study, we correlated plasma vWF levels with organ failure, liver disease severity, sepsis, and systemic inflammatory response syndrome (SIRS) and also analyzed if vWF levels predicted in-hospital composite poor outcome (i.e. death/discharged in terminal condition/liver transplantation) in consecutive ACLF patients.

RESULTS

Twenty-one of the 50 ACLF patients studied had composite poor outcome. ACLF patients had markedly elevated vWF antigen and activity (sevenfold and fivefold median increase, respectively) on days 1 and 3. Median ratio of vWF to a disintegrin and metalloprotease with thrombospondin type 1 motif, member 13 (ADAMTS13) activity on day 1 was significantly higher in ACLF patients (11.2) compared to 20 compensated cirrhosis patients (3.3) and healthy volunteers (0.9). On day 1, area under ROC curve (AUROC) to predict composite poor outcome of hospital stay for ACLF patients for vWF antigen, vWF activity, and model for end-stage liver disease (MELD) score were 0.63, 0.68, and 0.74, respectively. vWF activity correlated better with liver disease severity (MELD score, ACLF grade) and organ failure (Sequential Organ Failure Assessment [SOFA] score) than vWF antigen; in contrast, neither vWF antigen nor activity correlated with platelet count, sepsis, or SIRS.

CONCLUSIONS

vWF levels are markedly elevated, correlate with organ failure, and predict in-hospital survival in ACLF patients. This data provides a mechanistic basis for postulating that vWF-reducing treatments such as plasma exchange may benefit ACLF patients.

Effect of combined treatment with immunoadsorption and membrane filtration on plasma coagulation--Results of a randomized controlled crossover study

The combined use of immunoadsorption (IA) and membrane filtration (MF) may markedly enhance removal of IgM and complement component C1q, supporting its use as an element of recipient desensitization in antibody-incompatible transplantation. However, coagulation factor removal may contribute to altered hemostasis, posing a risk of bleeding in the perioperative setting. This secondary endpoint analysis of standard coagulation assays and rotational thromboelastometry (ROTEM®) was performed in the context of a randomized controlled crossover study designed to assess the effect of combined IA (GAM-146-peptide) and MF on levels of ABO antigen-specific IgM. Fourteen patients with autoimmune disorders were randomized to a single treatment with IA+MF followed by IA alone, or vice versa. MF was found to markedly enhance fibrinogen depletion (57% vs. 28% median decrease after IA alone, P < 0.001), whereby four patients showed post-treatment fibrinogen concentrations below 100 mg dL(-1). In support of a critical contribution of fibrinogen depletion to impaired coagulation, extrinsically activated ROTEM(®) analysis revealed a marked reduction in fibrinogen-dependent clot formation upon IA+MF (59% median decrease in FIBTEM mean clot firmness (MCF) as compared to 24% after IA alone, P < 0.001). Moreover, the addition of MF led to a substantial prolongation of activated partial thromboplastin time, possibly due to depletion of macromolecular coagulation factors contributing to intrinsically activated coagulation. Our study demonstrates substantial effects of combined IA+MF on clot formation, which may be mainly attributable to fibrinogen depletion. We suggest that the use of combined apheresis in the setting of transplant surgery may necessitate a careful monitoring of coagulation.

Recurring extracorporeal circuit clotting during continuous renal replacement therapy resolved after single-session therapeutic plasma exchange

We report a case of a 17-year-old white male with multiple fractures and multiorgan failure who developed oliguric acute renal failure requiring continuous renal replacement therapy. Repeated clotting of the extracorporeal circuit (ECC) prevented delivery of a minimally acceptable dose of renal replacement therapy despite adequate anticoagulation and dialysis catheter exchanges. Evaluation for a primary hypercoagulable state was negative, but his fibrinogen was elevated (1,320 mg/dL, normal range: 150-400 mg/dL), which is likely induced by his severe inflammatory state. A single session of therapeutic plasma exchange (TPE) with albumin and normal saline replacement was performed with subsequent drop in fibrinogen to 615 mg/dL. No further episodes of premature ECC clotting occurred, suggesting plasma factor(s) removed may have contributed to the clinical hypercoagulable state. TPE may play an adjunctive role in select cases of recurrent ECC clotting refractory to current anticoagulation techniques.

Double filtration plasmapheresis in antibody-incompatible kidney transplantation

Double filtration plasmapheresis (DFPP) was used in preference to plasma exchange in our program of antibody-incompatible transplantation, to treat higher volumes of plasma. Forty-two patients had 259 sessions of DFPP, 201 pre-transplant and 58 post-transplant. At the first treatment session, the mean plasma volume treated was 3.81 L (range 3-6 L), 55.5 mL/kg (range 36.2-83.6 mL/kg). Serum IgG fell by mean 59.4% (SD 10.2%), and IgM by 69.3% (SD 16.1%). Nine patients did not require increases in plasma volumes treated, and six did not tolerate higher plasma volumes. In the remaining patients, the mean maximum plasma volume treated pre-transplant was 6.67 L (range 4-15 L), 96.1 mL/kg (range 60.2-208.9 mL/kg). The complement dependent cytotoxic crossmatch was positive in 14 cases pre-treatment, and remained positive in six (42.8%) cases. The flow cytometric crossmatch was positive in 29 cases pre-treatment, and in 21 (72.4%) after DFPP. Post-transplant, DFPP was ineffective at reducing donor specific antibody levels during periods of rapid donor specific antibody synthesis. Post-transplant, the one year graft survival rate was 94%, although there was a high rate of early rejection. In summary, DFPP enabled the treatment of plasma volumes that were almost double those that would have been feasible with plasma exchange. Despite this, most patients were transplanted with a positive crossmatch, and DFPP post-transplant was unable to control rising antibody levels.

Impact of Double-Filtration Plasmapheresis in Combination with Interferon and Ribavirin in Living Donor Liver Transplant Recipients with Hepatitis C

Double-filtration plasmapheresis (DFPP) selectively removes high molecular weight substances including hepatitis C virus (HCV). Four live donor liver transplantation (LDLT) recipients with HCV received combination therapy with low-dose interferon (IFN) and ribavirin with DFPP. Three patients underwent this therapy for prophylaxis of HCV recurrence, and one for treating fibrosing cholestatic hepatitis (FCH). The combination therapy and DFPP decreased HCV RNA levels to 8.2% +/- 2.9% and 0.7% +/- 0.5% by the 5th and 30th day of treatment, respectively. Three patients who underwent DFPP for prophylaxis showed no evidence of HCV recurrence for >1 year after treatment. The patient whose graft showed FCH, recovered dramatically after the DFPP treatment. DFPP appeared to be effective in reducing HCV viremia and preventing HCV recurrence in patients with high HCV RNA levels after LDLT. Moreover, it may become a rescue therapy for FCH in a liver transplant recipient with hepatitis C.

Clearance Studies During Subsequent Sessions of Double Filtration Plasmapheresis

To evaluate the optimal session of double filtration plasmapheresis (DFP) in terms of the maximal clearance rates for various serum substances, the laboratory parameters of 152 consecutive patients treated with different sessions of DFP following a standard protocol on an alternate-day basis was studied. Immunoglobulin M (IgM) and lipoprotein cholesterol had the most effective clearance by a minimum of two sessions of DFP treatment, and the clearance rates remained relatively constant despite the increase in the number of treatment sessions, while the clearance rates for other serum proteins increased steadily with further treatments. Using the clearance rate of the 2-session group as reference, the highest slopes for clearance of albumin, globulin, and triglyceride were found in the 4-session group, while the slopes for IgA and IgG were highest in the 5-session group. In conclusion, for the clearance of IgM and lipoprotein cholesterol, two sessions of DFP treatment are adequate. However, the best clearance of IgG and other globulins cannot be achieved until the fourth session of DFP treatment. Therefore, a minimum of 4 sessions of DFP treatment at 2-day intervals is needed for most immunological diseases.

Complications of double-filtration plasmapheresis

BACKGROUND

Double-filtration plasmapheresis (DFP) removes high-molecular-weight molecules semiselectively, thereby minimizing albumin loss, but with subsequent need for fluid substitution. The purpose of this study was to establish the overall incidence of complications during DFP and to analyze the possible contributory factors.

STUDY DESIGN AND METHODS

From November 1993 to October 2003, a total of 2502 plasmapheresis procedures were performed during 515 courses of plasmapheresis in 335 patients. The medical and technical records for these patients were reviewed.

RESULTS

The overall frequency of complications was 67.5 percent per patient, 60.0 percent per course, and 26.3 percent per procedure. The rate of major complications was 18.2 percent of patients, 13.2 percent of courses, and 2.7 percent of procedures. Hemolysis, the most common complication of DFP, occurred in 20 percent of patients. A total of 83 (3.3%) episodes of hypotension were documented in 63 patients. Vascular-access-related complications constituted approximately 17 percent of the total. There was one documented episode of clinically overt bleeding from laboratory coagulopathy necessitating infusion of fresh plasma to stop bleeding. There was no allergic reaction or mortality associated with the DFP procedures. The per-patient frequency of hypotension was higher in cases of chronic inflammatory neuropathy (35.1%) compared to the other illness categories (15.4%-17.3%), with marginal significance demonstrated (p = 0.0611).

CONCLUSION

The safety of DFP treatment has been confirmed by this study. High-risk patients should be monitored carefully during treatment to minimize the occurrence of complications.