Early use of hemoadsorption in patients after out-of hospital cardiac arrest - a matched pair analysis

The role of a hemoadsorption filter on cytokine levels during 1 hour of thoraco-abdominal normothermic regional perfusion for donation after circulatory death heart donation in a porcine model

BACKGROUND

Both global ischemia caused by circulatory arrest and extracorporeal circulation circuits have been shown to trigger cytokine release. We hypothesized that inserting a hemoadsorption device during thoraco-abdominal normothermic regional perfusion (TA-NRP) in the donation after circulatory death setting would mitigate the inflammatory response, potentially resulting in improved cardiac allograft function.

METHODS

In 15 pigs, circulatory arrest was induced by hypoxia. After a 15-min no-touch-period, TA-NRP was performed for 60 min. Eight pigs had a hemoadsorption device incorporated in the ECC, while seven did not. Plasma concentrations of IFN-α, IFN-γ, TNF-α, IL-1β, IL-4, IL-6, IL-8, IL-10, and IL-12p40 were assessed by ELISA at baseline, immediately at start of TA-NRP, 60 min after start of TA-NRP (just before weaning from ECC), and at 30 and 60 min after weaning from ECC. Cardiac function was assessed with pressure-volume loop analysis.

RESULTS

Hemoadsorption had no relevant effects on systemic cytokine levels post TA-NRP. IL-6 plasma levels gradually rose throughout the procedure for both groups. Hemoadsorption did not affect systolic or diastolic left ventricular function, nor were global hemodynamics improved by hemoadsorption.

CONCLUSIONS

The insertion of a hemoadsorption device did not significantly affect plasma cytokine levels or cardiac function. Further research is necessary to assess the role of the inflammatory response in DCD heart transplantation and its modulation by TA-NRP.

Increased rate of anoxic brain damage with laryngeal tube compared to endotracheal intubation in patients with shockable out-of-hospital cardiac arrest - Experience from the HAnnover COoling REgistry (HACORE)

BACKGROUND

Supraglottic airway devices such as the laryngeal tube (LT) are recommended in current guidelines for simplified airway management in patients during and immediately after out-of-hospital cardiac arrest (OHCA). Trials evaluating LTs included predominantly OHCA patients with non-shockable rhythms and low survival rates. Hence, LTs are widely used, but their impact on preventing hypoxic brain damage during resuscitation has not been evaluated yet.

METHODS

We analysed 452 OHCA-patients with shockable-rhythms from the HAnnover COoling REgistry (HACORE) who had return of spontaneous circulation prior to transport. Of those, 405 patients received primary airway management by endotracheal intubation (ETI) and 47 by LT. Patients were afterwards treated according to the Hannover Cardiac Resuscitation Algorithm (HaCRA) applying a strict post-resuscitation management including therapeutic hypothermia and avoiding routine prognostication.

RESULTS

While mortality in this group was moderate with both airway strategies (ETI 29 % vs LT 34 %, p = 0.487), the rate of anoxic brain damage was much higher in the LT compared to the ETI group (38 % vs 21 %, p = 0.011). Survivors in the ETI group were more likely to have good neurological outcome (cerebral performance category 1&2) compared to the LT group (35 % vs 17 %, p = 0.013). Pneumonia was more common in the LT vs ETI group (81 % vs 53 %, p < 0.001).

CONCLUSIONS

While the original prehospital pragmatic trials comparing LT to ETI mostly included patients with non-shockable rhythm in settings with high mortality, our analysis is based on a real-world registry and focuses on successfully resuscitated patients, whose cause of arrest was most probably not due to hypoxia. In this cohort, use of LT was associated with a higher rate of anoxic brain damage and worse functional neurological outcome compared to use of ETI.

Efficacy of CytoSorb®: a systematic review and meta-analysis

INTRODUCTION

Cytokine adsorption using the CytoSorb® adsorber has been proposed in various clinical settings including sepsis, ARDS, hyperinflammatory syndromes, cardiac surgery or recovery after cardiac arrest. The aim of this analysis is to provide evidence for the efficacy of the CytoSorb® adsorber with regard to mortality in various settings.

METHODS

We searched PubMed, Cochrane Library database and the database provided by Cytosorbents™ (01.1.2010-29.5.2022). We considered randomized controlled trials and observational studies with control groups. The longest reported mortality was defined as the primary endpoint. We computed risk ratios and 95%-confidence intervals and used DerSimonian and Lairds random effects model. We analysed all studies combined and divided them into the subgroups: sepsis, cardiopulmonary bypass surgery (CPB), other severe illness, SARS-CoV-2 infection and recovery from cardiac arrest. The meta-analysis was registered in advance (PROSPERO: CRD42022290334).

RESULTS

Of an initial 1295 publications, 34 studies were found eligible, including 1297 patients treated with CytoSorb® and 1314 controls. Cytosorb® intervention did not lower mortality (RR [95%-CI]: all studies 1.07 [0.88; 1.31], sepsis 0.98 [0.74; 1.31], CPB surgery 0.91 [0.64; 1.29], severe illness 0.95 [0.59; 1.55], SARS-CoV-2 1.58 [0.50; 4.94]). In patients with cardiac arrest, we found a significant survival advantage of the untreated controls (1.22 [1.02; 1.46]). We did not find significant differences in ICU length of stay, lactate levels, or IL-6 levels after treatment. Of the eligible 34 studies only 12 were randomized controlled trials. All observational studies showed moderate to serious risk of bias.

INTERPRETATION

To date, there is no evidence for a positive effect of the CytoSorb® adsorber on mortality across a variety of diagnoses that justifies its widespread use in intensive care medicine.

Survival of Patients Treated With Extracorporeal Hemoadsorption and Extracorporeal Membrane Oxygenation: Results From a Nation-Wide Registry

Extracorporeal hemoadsorption with the CytoSorb adsorber is increasingly being used during the past years. The use in combination with extracorporeal membrane oxygenation (ECMO) is feasible, but frequency of its use and outcomes have not been assessed in larger cohorts. We analyzed all patients treated with veno-venous (VV) ECMO either with or without CytoSorb in Germany from 2017 to 2019. Data were retrieved from a nationwide claim dataset collected by the Research Data Center of the Federal Bureau of Statistics. During this three-year episode, 7,699 patients were treated with VV ECMO. Among these, the number of CytoSorb-treated patients constantly increased from 156 (6.6%) in 2017 to 299 (11.8%) in 2019. In this large cohort hemoadsorption with the CytoSorb adsorber was associated with higher mortality and increased treatment costs. Due to limited information in the dataset about the severity of disease comparison of outcomes of patients treated with and without CytoSorb has to be interpreted with caution. Further studies have to examine if this finding is due to a negative effect of hemoadsorption with the CytoSorb device or is rather to be attributed to disease severity.

Cytokine hemoadsorption with CytoSorb® in post-cardiac arrest syndrome, a pilot randomized controlled trial

BACKGROUND

Hemoadsorption (HA) might mitigate the systemic inflammatory response associated with post-cardiac arrest syndrome (PCAS) and improve outcomes. Here, we investigated the feasibility, safety and efficacy of HA with CytoSorb® in cardiac arrest (CA) survivors at risk of PCAS.

METHODS

In this pilot randomized controlled trial, we included patients admitted to our intensive care unit following CA and likely to develop PCAS: required norepinephrine (> 0.2 µg/kg/min), and/or had serum lactate > 6 mmol/l and/or a time-to-return of spontaneous circulation (ROSC) > 25 min. Those requiring ECMO or renal replacement therapy were excluded. Eligible patients were randomly allocated to either receive standard of care (SOC) or SOC plus HA. Hemoadsorption was performed as stand-alone therapy for 24 h, using CytoSorb® and regional heparin-protamine anticoagulation. We collected feasibility, safety and clinical data as well as serial plasma cytokines levels within 72 h of randomization.

RESULTS

We enrolled 21 patients, of whom 16 (76%) had out-of-hospital CA. Median (IQR) time-to-ROSC was 30 (20, 45) minutes. Ten were assigned to the HA group and 11 to the SOC group. Hemoadsorption was initiated in all patients allocated to the HA group within 18 (11, 23) h of ICU admission and conducted for a median duration of 21 (14, 24) h. The intervention was well tolerated except for a trend for a higher rate of aPTT elevation (5 (50%) vs 2 (18%) p = 0.18) and mild (100-150 G/L) thrombocytopenia at day 1 (5 (50%) vs 2 (18%) p = 0.18). Interleukin (IL)-6 plasma levels at randomization were low (< 100 pg/mL) in 10 (48%) patients and elevated (> 1000 pg/mL) in 6 (29%). The median relative reduction in IL-6 at 48 h was 75% (60, 94) in the HA group versus 5% (- 47, 70) in the SOC group (p = 0.06).

CONCLUSIONS

In CA survivors at risk of PCAS, HA was feasible, safe and was associated with a nonsignificant reduction in cytokine plasma levels. Future trials are needed to further define the role of HA after CA. Those studies should include cytokine assessment to enrich the study population.

TRIAL REGISTRATION

NCT03523039, registered 14 May 2018.

Adverse outcomes with extracorporeal adsorbent blood treatments in toxic systemic inflammation: a perspective on possible mechanisms

Background

Extracorporeal blood purification (EBP) treatments may be used in patients with sepsis and related conditions to mitigate toxic systemic inflammation, prevent or reverse vital organ injury, and improve outcome. These treatments lack demonstrable efficacy, but are generally considered safe. However, since late 2020, four clinical studies of EBP treatment using adsorbent devices in inflammatory disease reported significantly increased patient mortality associated with the adsorbent treatments. Criticisms of study design and execution were published, but revealed no decisive flaws. None of these critiques considered possible toxic effects of the adsorbent treatments per se.

Perspective and conclusion

In adsorbent EBP treatment of systemic inflammatory disease the adsorbent media are deployed in patient blood or plasma flow for the purpose of broad spectrum, non-specific adsorptive removal of inflammatory mediators. Adsorption and sequestration of inflammatory mediators by adsorbent media is intended to reduce mediator concentrations in circulating blood and neutralize their activity. However, in the past two decades developments in both biomedical engineering and the science of cytokine molecular dynamics suggest that immobilization of inflammatory proteins on solid scaffolds or molecular carriers may stabilize protein structure and preserve or amplify protein function. It is unknown if these mechanisms are operative in EBP adsorbent treatments. If these mechanisms are operative, then the adsorbent medium could become reactive, promoting inflammatory activity which could result in negative outcomes. Considering the recent reports of harm with adsorbent treatments in diverse inflammatory conditions, caution urges investigation of these potentially harmful mechanisms in these devices. Candidate mechanisms for possible inquiry are discussed.

Additive Impact of Interleukin 6 and Neuron Specific Enolase for Prognosis in Patients With Out-of-Hospital Cardiac Arrest – Experience From the HAnnover COoling REgistry

Background

Patients after out-of-hospital cardiac arrest (OHCA) are at increased risk for mortality and poor neurological outcome. We assessed the additive impact of interleukin 6 (IL-6) at admission to neuron-specific enolase (NSE) at day 3 for prognosis of 30-day mortality and long-term neurological outcome in OHCA patients.

Methods

A total of 217 patients from the HAnnover COoling REgistry with return of spontaneous circulation (ROSC) after OHCA and IL-6 measurement immediately after admission during 2017–2020 were included to investigate the prognostic value and importance of IL-6 in addition to NSE obtained on day 3. Poor neurological outcome was defined by cerebral performance category (CPC) ≥ 3 after 6 months.

Results

Patients with poor outcome showed higher IL-6 values (30-day mortality: 2,224 ± 524 ng/l vs 186 ± 15 ng/l, p &lt; 0.001; CPC ≥ 3 at 6 months: 1,440 ± 331 ng/l vs 180 ± 24 ng/l, p &lt; 0.001). IL-6 was an independent predictor of mortality (HR = 1.013/ng/l; 95% CI 1.007–1.019; p &lt; 0.001) and poor neurological outcome (HR = 1.004/ng/l; 95% CI 1.001–1.007; p = 0.036). In ROC-analysis, AUC for IL-6 was 0.98 (95% CI 0.96–0.99) for mortality, but only 0.76 (95% CI 0.68–0.84) for poor neurological outcome. The determined cut-off value for IL-6 was 431 ng/l for mortality (NPV 89.2%). In patients with IL-6 &gt; 431 ng/l, the combination with NSE &lt; 46 μg/l optimally identified those individuals with potential for good neurological outcome (CPC ≤ 2).

Conclusion

Elevated IL-6 levels at admission after ROSC were closely associated with 30-day mortality. The combination of IL-6 and NSE provided clinically important additive information for predict poor neurological outcome at 6 months.

Multi-organ dysfunction syndrome in patients undergoing extracorporeal life support

BACKGROUND

Multiple organ failure is a common complication in patients undergoing ECLS significantly affecting patient outcomes. Gaining knowledge about the mechanisms of onset, clinical course, risk factors, and potential therapeutic targets is highly desirable.

METHODS

Data of 354 patients undergoing ECLS with one-, two, three-, and four organ failures were retrospectively analyzed. Incidence of multiple organ dysfunction (MODS), its impact on survival, risk factors for its occurrence, and the impact of proinflammatory mediators on the occurrence of MODS in patients undergoing ECLS were investigated.

RESULTS

The median follow-up was 66 (IQR 6; 820) days. 245 (69.2%) patients could be weaned from ECLS, 30-day survival and 1-year survival were 194 (54.1%) and 157 (44.4%), respectively. The duration of mechanical support was 4 (IQR 2; 7) days in the median. Increasing severity of MODS resulted in significant prolongation of mechanical circulatory support and worsening of the outcome. Liver dysfunction had the strongest impact on patient mortality (OR = 2.5) and survival time (19 vs 367 days). The serum concentration of analyzed interleukins rose significantly with each, additional organ affected by dysfunction (p < 0.001). All analyzed proinflammatory cytokines showed significant predictivity relative to the occurrence of MODS with interleukin 8 serum level prior to ECLS showing the strongest predictive potential for the occurrence of MODS (AUC 0.78).

CONCLUSION

MODS represents a frequent complication in patients undergoing ECLS with a significant impact on survival. Proinflammatory cytokines show prognostic capacity regarding the occurrence and severity of multi-organ dysfunction.

The Potential Role of Extracorporeal Cytokine Removal in Hemodynamic Stabilization in Hyperinflammatory Shock

Hemodynamic instability due to dysregulated host response is a life-threatening condition requiring vasopressors and vital organ support. Hemoadsorption with Cytosorb has proven to be effective in reducing cytokines and possibly in attenuating the devastating effects of the cytokine storm originating from the immune over-response to the initial insult. We reviewed the PubMed database to assess evidence of the impact of Cytosorb on norepinephrine needs in the critically ill. We further analyzed those studies including data on control cohorts in a comparative pooled analysis, defining a treatment effect as the standardized mean differences in relative reductions in vasopressor dosage at 24 h. The literature search returned 33 eligible studies. We found evidence of a significant reduction in norepinephrine requirement after treatment: median before, 0.55 (IQR: 0.39-0.90); after, 0.09 (0.00-0.25) μg/kg/min, p < 0.001. The pooled effect size at 24 h was large, though characterized by high heterogeneity. In light of the importance of a quick resolution of hemodynamic instability in the critically ill, further research is encouraged to enrich knowledge on the potentials of the therapy.

Cytokine adsorption in patients with severe COVID-19 pneumonia requiring extracorporeal membrane oxygenation (CYCOV): a single centre, open-label, randomised, controlled trial

Background

We sought to clarify the benefit of cytokine adsorption in patients with COVID-19 supported with venovenous extracorporeal membrane oxygenation (ECMO).

Methods

We did a single-centre, open-label, randomised, controlled trial to investigate cytokine adsorption in adult patients with severe COVID-19 pneumonia requiring ECMO. Patients with COVID-19 selected for ECMO at the Freiburg University Medical Center (Freiburg, Germany) were randomly assigned (1:1) to receive cytokine adsorption using the CytoSorb device or not. Randomisation was computer-generated, allocation was concealed by opaque, sequentially numbered sealed envelopes. The CytoSorb device was incorporated into the ECMO circuit before connection to the patient circuit, replaced every 24 h, and removed after 72 h. The primary endpoint was serum interleukin-6 (IL-6) concentration 72 h after initiation of ECMO analysed by intention to treat. Secondary endpoints included 30-day survival. The trial is registered with ClinicalTrials.gov (NCT04324528) and the German Clinical Trials Register (DRKS00021300) and is closed.

Findings

From March 29, 2020, to Dec 29, 2020, of 34 patients assessed for eligibility, 17 (50%) were treated with cytokine adsorption and 17 (50%) without. Median IL-6 decreased from 357·0 pg/mL to 98·6 pg/mL in patients randomly assigned to cytokine adsorption and from 289·0 pg/mL to 112·0 pg/mL in the control group after 72 h. One patient in each group died before 72 h. Adjusted mean log IL-6 concentrations after 72 h were 0·30 higher in the cytokine adsorption group (95% CI −0·70 to 1·30, p=0·54). Survival after 30 days was three (18%) of 17 with cytokine adsorption and 13 (76%) of 17 without cytokine adsorption (p=0·0016).

Interpretation

Early initiation of cytokine adsorption in patients with severe COVID-19 and venovenous ECMO did not reduce serum IL-6 and had a negative effect on survival. Cytokine adsorption should not be used during the first days of ECMO support in COVID-19.

Funding

None.