Regional Citrate Anticoagulation during Double-Filtration Plasmapheresis in Kidney Transplant Recipients: A Single-Center Retrospective Cohort Study

The Application of Regional Citrate Anticoagulation in Protein A Immunoadsorption: A Single-Center Retrospective Cohort Study

Introduction

Protein A immunoadsorption (IA) is proving to be an effective treatment method for autoimmune diseases and other disorders. Regional citrate anticoagulation (RCA) prevents clotting in extracorporeal circuits without increasing hemorrhage risk in high bleeding risk patients, but there are no specific guidelines for its application in IA. We aimed to evaluate the safety and adverse effects of RCA used in IA therapy.

Methods

We conducted a retrospective cohort study of forty-five RCA-IA sessions in 14 HLA-incompatible kidney transplant recipients with focus on the safety and adverse effects of RCA in IA. The extracorporeal circuit was equipped with 4% trisodium citrate solution as an anticoagulant and 10% calcium gluconate solution to compensate for calcium loss. The adverse events, including coagulation and blood biochemical indexes, especially calcium level, were recorded.

Results

Our study found that 93.33% of the sessions were without circuit clotting or other significant complications. A slight decrease in fibrinogen level was observed, but without significant variations in other coagulation indexes or platelet count. There was a slight elevation in the potential of hydrogen, bicarbonate, and base excess after 2 h and 6 h posttreatment relative to prior treatment, but these returned to normal levels within 24 h posttreatment.

Conclusion

RCA is a feasible, effective, and safe anticoagulation option for IA treatment in HLA-incompatible kidney transplant recipients. Electrolyte disturbances, especially alkalosis, hypocalcemia, hypomagnesemia, and fluid status, should be closely monitored and managed.

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.

Regional citrate anticoagulation vs systemic heparin anticoagulation for double-filtration plasmapheresis

INTRODUCTION

Double-filtration plasmapheresis (DFPP) has been utilized for immunomodulation in kidney transplantation. Anticoagulation is important to maintain circuit patency during DFPP. We aimed to compare the efficacy and safety of regional citrate anticoagulation (RCA) with systemic heparin anticoagulation during DFPP in kidney transplant recipients.

METHODS

A retrospective cohort study was conducted to compare the efficacy and safety of RCA (RCA-DFPP) to systemic heparin anticoagulation (Hep-DFPP) for DFPP among kidney transplant recipients in a single tertiary center.

RESULTS

A total of 112 sessions of DFPP were performed for 23 subjects, of which 62 sessions were RCA-DFPP and 50 sessions were Hep-DFPP. There were 13 sessions (11.6%) of premature circuit clotting, 10 sessions (16.1%) for RCA-DFPP and 3 sessions (6.0%) for Hep-DFPP (P = .10). All premature circuit clotting episodes occurred in subjects who underwent DFPP through a vascular catheter. Premature circuit clotting was associated with the use of a vascular catheter (odds ratio [OR] 14.2, 95% confidence interval [CI] 2.7-73.7; P < .01) and high postfilter ionized calcium (OR 12.7, 95% CI 1.4-112.5; P < .01). There was no major bleeding event. Hep-DFPP was associated with higher occurrence of hypocalcemia (OR 1.1, 95% CI 1.0-1.2; P < .01) and metabolic acidosis (OR 1.4, 95% CI 1.2-2.0; P = .04), while hypomagnesemia was more common for RCA-DFPP (OR 2.9, 95% CI 1.1-7.4; P = .03).

CONCLUSION

Amongst kidney transplant patients who receive DFPP therapy, RCA-DFPP may be comparable to Hep-DFPP for the maintenance of circuit patency. Functioning vascular access is vital in avoiding premature clotting of the circuit. Close monitoring of electrolyte imbalances and coagulopathy related to DFPP is recommended.