Early initiation of Extracorporeal Blood Purification using the AN69ST (oXiris®) hemofilter as a treatment modality for COVID - 19 patients: a single-centre case series

Abstract

Introduction: Our understanding of the COVID-19 disease has been steadily evolving since the original outbreak in December 2019. Advanced disease is characterised by a hyperinflammatory state, systemic coagulopathies and multiorgan involvement, in particular respiratory distress. We here describe our initial experience with treating of COVID-19 patients based on early initiation of extracorporeal blood purification, systemic heparinisation and respiratory support.Methods: 15 patients were included; 2 were females. We monitored real-time several biochemical, immunological and coagulation biomarkers associated with disease severity following admission to our dedicated COVID-19 intensive care unit. To guide personalised treatment, we monitored among others levels of IL-6, IL-8, TNF-α, C-Reactive Protein (CRP), Neutrophil-to-Lymphocyte ratios, Thrombocyte counts, D-Dimers, Fibrinogen, and Activation Clotting time (ACT).Treatment consisted of individualised respiratory support supplemented with 1 - 4 cycles of 24-hour Extracorporeal Organ Support (ECOS) and Blood Purification using the AN69ST (oXiris®) hemofilter. We administered heparin (300 U/kg) to counter suspected hypercoagulability (= elevated Fibrinogen or D-dimers) states to maintain ACT ≥ 180 seconds.Results: N = 10 presented with severe to critical disease (= dyspnoea, hypoxia, respiratory rate > 30/min, peripheral oxygen saturation < 90%, or > 50% lung involvement on X-ray imaging). A single case was admitted with a critical condition (= respiratory failure). One patient died after 5 days of hospitalisation after developing Acute Respiratory Syndrome. 8 Patients have been discharged - average ICU length-of-stay was 9.9 ± 2.4 days. Clinical improvement was associated with normalisation (increase) of thrombocytes, white blood cells, stable levels of IL-6 (< 50 ng/mL) and a decrease of CRP and Fibrinogen. Conclusion: Means to monitor COVID-19 disease severity during hospitalisation are crucial to control disease progression and prevent hyperinflammation and irreversible multiorgan failure. We present here a real-time monitoring system accounting for biochemical, immunological, coagulation parameters and radiological imaging. The combination of systemic heparin anticoagulation regimens and blood purification may prevent hyperinflammation, thromboembolism during hospitalisation and thus support clinical recovery.

Cytokine storm and COVID-19: a chronicle of pro-inflammatory cytokines

“…We [124] and others [125] have observed that hospitalized COVID-19 patients show extremely elevated D-dimers (greater than 500 ng ml −1 ) and Fibrinogen (greater than 5.5 g l −1 ) levels; some severely ill patients are admitted with D-dimers of greater than 20 000 ng ml −1 evidencing a severe hypercoagulable state.…”

“…Several recent reports provide promising observations in regards to the control of hyperinflammation; cytokine adsorption, blood purification, effectively decreased levels of IL-6 in advanced COVID-19 disease [124,130,143]. Nevertheless, randomized controlled trials are warranted to determine the calibre of blood purification regimens to promote clinical recovery of COVID-19 patients.…”

Extracorporeal Blood Purification in moderate and severe COVID-19 patients: a prospective cohort study

“…The general treatment protocol is shown in Figure 2 and follows practice safety recommendations, treatment strategies and up-to-date sepsis management guidelines [18][19][20][21]. The multidisciplinary care and therapeutic approach were previously described in detail by Ugurov et al [15] Extracorporeal Blood Purification The Prismaflex® oXiris® system was mounted in the ICU and connected 4 -12 hours after admission upon establishing control of the haemostasis, ACT = Activated Coagulation Time of 180 secs. The patient is connected to the Prismaflex® oXiris® system via a double lumen catheter placed in the femoral vein or vena subclavia.…”

“…One patient experienced a hematoma following venous cannulation that required a catheter displacement. Our complete treatment approach was previously documented [15] In parallel, during hospitalisation, 12 critical patients were treated with i.v. Dexamethasone at a dose of 8 mg q.d.…”

“…We here describe a case series of 44 COVID-19 patients treated with CVVHF-CAH using the AN69ST (oXiris®) filter and present longitudinal analysis of clinical and laboratory parameters associated with disease severity. EBP was supplemented with systemic heparinisation and non-invasive respiratory [15] support aimed at preventing irreversible lung pathology [16] and the necessity of invasive mechanical ventilation. Mechanical respiratory support is linked to high mortality rates, especially in older patients or those with severe comorbidities [17].…”