Application of regional citrate anticoagulation in membrane therapeutic plasma exchange

Citrate anticoagulation in plasma exchange followed by continuous renal replacement therapy in critically ill children

OBJECTIVE

To investigate the effectiveness and safety of regional citrate-anticoagulated (RCA) plasma exchange (PE) and whether citrate-related metabolic disorders can be improved by sequential RCA continuous renal replacement therapy (CRRT).

METHODS

This retrospective, single-center observational study included 79 critically ill children requiring PE followed by CRRT (June 2018 to June 2021) at the Pediatric Intensive Care Unit of Hunan Children's Hospital, China. Patients were divided into the RCA-PE (n = 30) and systemic heparin anticoagulation (SHA-PE) (n = 49) groups. Filter level comparison post-PE assessed RCA-PE efficacy, and metabolic changes occurring pre- and post-PE and CRRT were used to evaluate the effect of CRRT on RCA-based anticoagulation safety.

RESULTS

The RCA-PE group had a better overall filter performance than the SHA-PE group. Two hours after PE, pH and HCO₃- levels increased more significantly for the RCA-PE than the SHA-PE group. The RCA-PE incidence of metabolic alkalosis was 48.3%, higher by 4.2% (p < 0.001) compared to the SHA-PE group. In the RCA-PE group, pH and HCO₃- decreased significantly 4 h after CRRT; the metabolic alkalosis caused by RCA-PE decreased to 13.8% (p = 0.005). No significant difference in pH, HCO₃-, and metabolic alkalosis incidence was observed between the two groups 4 h after CRRT.

CONCLUSIONS

The overall filtration performance of RCA-PE is superior to that of SHA-PE followed by CRRT. The metabolic complications associated with RCA-PE are mainly metabolic alkalosis that can be improved by using CRRT after RCA-PE and this is a better alternative for anticoagulation during PE in critically ill children.

Heparin anticoagulation versus regional citrate anticoagulation for membrane therapeutic plasma exchange in patients with increased bleeding risk

Background Heparin anticoagulation (HA) is commonly employed for membrane therapeutic plasma exchange (mTPE). However, for patients with increased bleeding risk, there were controversial opinions on the use of HA versus regional citrate anticoagulation (RCA) for mTPE. Our present study aimed to evaluate the efficacy and safety of HA vs. RCA for mTPE in patients with increased bleeding risk.Methods Patients with increased bleeding risk who underwent mTPE between 2014 and 2021 in our center were screened. Observations of anticoagulation efficacy and safety were used as the study endpoints.Results A total of 108 patients with 368 mTPE sessions were included. Of the included patients, 38 and 70 received HA and RCA mTPE, respectively. There was no significant difference in the clotting of extracorporeal circuits between the HA and RCA groups (4.1% vs. 4.4%, p = 0.605). More bleeding episodes were observed in the HA group compared to the RCA group (16.4% vs. 4.4% mTPE sessions, p < 0.001). The frequency of postoperative transfusion within 24 h (11% vs. 3.4%, p = 0.007) was significantly different in the HA and RCA group. Anticoagulation strategy (HA vs. RCA; OR 5.659, 95%CI 2.266-14.129; p < 0.001), and mean arterial pressure (prior treatment, OR 1.052, 95%CI 1.019-1.086; p = 0.002) were independent risk factors of bleeding episodes. At the end of mTPE treatment, the incidence of metabolic alkalosis (16.7% vs. 54.1%, p = 0.027) and hypocalcemia (41.7% vs. 89.2%, p = 0.001) was significantly different in the HA (n = 5, 12 sessions) and RCA (n = 22, 74 sessions) groups, respectively.Conclusion RCA is as effective as HA for mTPE. However, for patients with increased bleeding risk, RCA is associated with a lower risk of bleeding, compared with HA. With careful monitoring and timely adjustment, RCA most likely is a safe and effective anticoagulation option for mTPE in patients with increased bleeding risk.

In hospitalized patients undergoing therapeutic plasma exchange, major bleeding prevalence depends on the bleeding definition: An analysis of The Recipient Epidemiology and Donor Evaluation Study-III

BACKGROUND

Major bleeding in patients undergoing therapeutic plasma exchange (TPE) has been studied in large databases; but without standardizing bleeding definitions. Therefore, we used standardized definitions to evaluate major bleeding in hospitalized patients undergoing TPE using public use data files from the Recipient Epidemiology and Donor Evaluation Study-III (REDS-III).

STUDY DESIGN AND METHODS

In a retrospective cross-sectional analysis, we identified TPE-treated adults in a first inpatient encounter. We evaluated major bleeding prevalence using (1) International Classification of Diseases (ICD) or Current Procedural Terminology (CPT) codes, (2) packed red blood cell (PRBC) transfusion, or (3) hemoglobin (Hgb) decline. Patients with major bleeding prior to their first TPE were excluded from the analysis.

RESULTS

Among 779 patients undergoing TPE, major bleeding by at least one of the three bleeding definitions occurred in 135 patients (17.3%). For each of the ICD/CPT, PRBC, and Hgb definitions, the prevalence of major bleeding was 2.8% (n = 31), 7.4% (n = 81), and 5.4% (n = 59), respectively. Only 3.7% of bleeds (5/135) were captured by all three definitions and 19.3% (26/135) exclusively by any two pairwise definitions. The addition of PRBC transfusion and Hgb decline to ICD/CPT code definitions increased bleeding prevalence threefold.

CONCLUSION

Among hospitalized adults undergoing TPE in the REDS-III study, the prevalence of major bleeding was 17.3%. The addition of PRBC and Hgb decline to ICD codes increased bleeding prevalence threefold. Future studies are needed to develop validated models that identify patients at risk for major bleeding during TPE.

Clinical application of regional citrate anticoagulation for membrane-based therapeutic plasma exchange in children with liver failure

Background

Regional citrate anticoagulation (RCA) is being used more commonly in children for continuous renal replacement therapy. Few reports describe the application of membrane-based therapeutic plasma exchange (mTPE) with RCA in children with liver failure (LF).

Aims

To explore the application of RCA-mTPE in children with LF.

Methods

We retrospectively analyzed data from children with LF who underwent RCA-mTPE in the Children's Hospital of Chongqing Medical University's pediatric intensive care unit. We used the total to ionized calcium ratio (T/iCa) > 2.5 as the diagnostic criteria for citrate accumulation (CA). The patients were divided into two groups according to the occureence of CA at the end of RCA-mTPE (CA group: T/iCa > 2.5; NCA group: T/iCa ≤ 2.5). To evaluate the clinical safety and efficacy of RCA-mTPE, the following data from medical records were assessed and compared between groups: clinical characteristics, reasons for LF, RCA-mTPE parameters and duration, laboratory findings, and complications.

Results

In total, 92 RCA-mTPE treatments were administered to 21 children with LF over 3.8 ± 0.9 h. The following mean values were determined: blood flow rate (QB) = 2.8 ml/kg/min, 4% sodium citrate dose/blood flow rate ratio (QCi/QB) = 1.1(QCi,ml/kg/h); plasma dose/body weight ratio(QP/BW) = 18.5 (QP, ml/kg/h); 10% calcium gluconate dose/blood flow rate ratio (QCa/QB) = 0.2(QCa, ml/kg/h). The mean concentration of iCa in vitro was 0.38 ± 0.07 mmol/L. Citrate accumulation was recorded after 34 (37%) treatments. Hypocalcemia occurred in 11 (12%) and 7 (7.6%) treatments, during and after mTPE, respectively. Three hypotensive and one convulsive events, related to hypocalcemia, and two clotting events occurred during RCA-mTPE. After RCA-mTPE, the patients' pH, HCO3- and Na+ levels, and T/iCa were significantly increased and the total bilirubin (TB), conjugated bilirubin (DB), prothrombin time (PT), activated partial thromboplastin time (APTT), alanine aminotransferase (ALT), aspartate aminotransferase (AST),and ammonia levels were significantly decreased. The TB, DB, and lactic acid levels, before RCA-mTPE, were significantly higher in the CA group than in the NCA group, but there were no significance between the two groups in QB/BW, QCi/QB, and QP/BW, mTPE duration, and estimated amount of citrate metabolized.

Conclusions

Children with LF undergoing RCA-mTPE are at risk of hypocalcemia. With proper protocol adjustment, however, RCA-mTPE can be used safely and effectively in these patients.

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.

Therapeutic plasma exchange in anti-N-methyl-D-aspartate receptor encephalitis

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is the most commonly identified cause of autoimmune encephalitis. Therapeutic plasma exchange has been increasingly employed to treat this disease. This expansion is a consequence of improved techniques and apheresis instruments, as well as the recognition of its applicability in neurological diseases. However, several aspects of treatment remain incompletely clarified, and treatment strategies are still heterogeneous, especially with regard to therapeutic plasma exchange in anti-NMDAR encephalitis. This review provides an overview of the use of therapeutic plasma exchange including the principle and mechanisms, the evidence, initial time, efficiency and complications in anti-NMDAR encephalitis.

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.