Kidney Week

Abstract: TH-PO1158

RescuE pLAsma eXchange in Severe COVID-19 (RELAX Trial): A Multicenter Randomized Controlled Trial

Session Information

• COVID-19
  October 24, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Coronavirus (COVID-19)

• 000 Coronavirus (COVID-19)

Authors

• Nusshag, Christian, Heidelberg University Hospital, Department of Nephrology, Heidelberg, Baden-Wuerttemberg, Germany

Christian Nusshag, MD, DrMed

• Morath, Christian, Heidelberg University Hospital, Department of Nephrology, Heidelberg, Baden-Wuerttemberg, Germany

Christian Morath, MD

• Kälble, Florian, Heidelberg University Hospital, Department of Nephrology, Heidelberg, Baden-Wuerttemberg, Germany

Florian Kälble

• Speer, Claudius, Heidelberg University Hospital, Department of Nephrology, Heidelberg, Baden-Wuerttemberg, Germany

Claudius Speer

• Meis, Jan, University of Heidelberg, Institute of Medical Biometry, Heidelberg, Baden-Wuerttemberg, Germany

Jan Meis, MSc

• Schwenger, Vedat, Klinikum Stuttgart Katharinenhospital, Department of Nephrology, Hypertension and Autoimmune Disorders, Heidelberg, Baden-Wuerttemberg, Germany

Vedat Schwenger, MD

• Brenner, Thorsten, University Hospital Essen, Department of Anesthesiology and Intensive Care Medicine, Heidelberg, Baden-Wuerttemberg, Germany

Thorsten Brenner, MD, PhD

• Zeier, Martin G., Heidelberg University Hospital, Department of Nephrology, Heidelberg, Baden-Wuerttemberg, Germany

Martin G. Zeier, MD, FASN

• Czock, David, Heidelberg University Hospital, Department of Clinical Pharmacology and Pharmacoepidemiology, Heidelberg, Baden-Wuerttemberg, Germany

David Czock, DrMed

• Weigand, Markus A., Heidelberg University Hospital, Department of Anesthesiology, Heidelberg, Baden-Wuerttemberg, Germany

Markus A. Weigand

• Merle, Uta, Heidelberg University Hospital, Department of Gastroenterology, Heidelberg, Baden-Wuerttemberg, Germany

Uta Merle, MD

Background

Evidence suggests a multi-level inflammatory syndrome in critically ill COVID-19 patients, resembling inflammatory, coagulopathic and autoimmune diseases. Plasma exchange (PE) is controversially discussed as a potential therapy. Here we report the first results of a multicenter, randomized controlled trial evaluating PE versus standard of care (SOC) in severe COVID-19.

Methods

Critically ill COVID-19 patients were enrolled in the RELAX trial (SOC n=33, SOC+PE n=34). Inclusion criteria were SARS-CoV-2-induced ARDS requiring mechanical ventilation, fever ≥ 38.5°C, D-dimer ≥ 2mg/dL, and dexamethasone therapy for at least two days. Patients received either SOC or SOC plus at least three PE treatments. The primary endpoint was 30-day mortality. Secondary endpoints included 60-, 90-, and 365-day mortality and procedure-related complications.

Results

The PE group underwent a median of 4 PE procedures (Interquartile range [IQR] 3-6), exchanging a plasma volume of 3.9L per treatment (IQR 3.7-3.9L). Hemodynamics and vasopressor support improved after PE treatments. Kaplan-Meier analysis showed no significant survival benefit at 30 days, but a significantly improved 90- and 365-day survival in the PE group (Figure 1). No severe complications occurred. Complications included allergic reactions (1.7%), hypertensive episodes (17.9%), hypocalcemia (75.7%), cardiac arrhythmia (0.6%), and catheter dysfunctions (1.7%). Allergic reactions were limited to skin rash, hypocalcemia was mild (1.1 mmol/L [IQR 1.0-1.1 mmol/L]), and arrhythmia occurred in one patient with prior episodes of atrial fibrillation.

Conclusion

Plasma exchange significnatly improved long-term survival in critically ill COVID-19 patients. Exploring potential mechanisms of PE on inflammation and coagulopathic drivers may have large clinical implications for other viral diseases and sepsis