In Vitro Apixaban Removal By CytoSorb Whole Blood Adsorber: An Experimental Study

Iodinated Contrast Adsorption in Cartridges With Styrene-Divinylbenzene Sorbent

BACKGROUND

Contrast-associated acute kidney injury (CA-AKI) is frequent in patients with chronic kidney disease who are submitted to cardiac endovascular procedures using iodinated contrast. In hemoadsorption, cartridges containing styrene-divinylbenzene sorbent resin are applied to remove substances from the blood through an extracorporeal circuit. Importantly, iodinated contrast is also removed via adsorption. We aimed to determine the adsorptive kinetics of the iodinated contrast medium iohexol using a 1:3 scale model of the HA380 cartridge.

METHODS

An experimental in vitro study utilizing a closed-loop extracorporeal circuit with an interposed sorbent cartridge. A solution spiked with iohexol was recirculated for 60 min. Samples for the measurement of iohexol were drawn at 0, 5, 10, 15, 20, 30, 40, and 60 min. The experiment was carried out twice.

RESULTS

In experiments 1 and 2, the reduction ratio after 60 min was 53.0% and 53.1%, respectively. In experiment 1, iohexol clearance was 46.79 mL/min during the first 5 min and decayed to 3.57 mL/min during the last 20 min. In experiment 2, iohexol clearance was 46.72 mL/min and decayed to 3.87 mL/min during the last 20 min. The ratio of adsorbate/sorbent was 155 mg/g.

CONCLUSION

A 1:3 scale model of the HA380 cartridge efficiently removes iodinated contrast in a clinical-scale in vitro circuit. These findings provide a rationale for hemoadsorption as an intervention in clinical trials to prevent or attenuate CA-AKI.

Low-dose apixaban in HeartMate 3 LVAD patients, interim analysis of the ApixiVAD trial, a randomized controlled study

BACKGROUND

Left ventricular assist devices (LVADs) improve outcomes in advanced heart failure but require anticoagulation. Vitamin K antagonists (VKAs) have significant limitations, with labile international normalized ratios and suboptimal time in therapeutic range (TTR), associated with increased morbidity and mortality. Direct oral anticoagulant therapy has been contraindicated in LVAD patients.

METHODS

The ApixiVAD study, a 1:1 randomized, open-label pilot trial, compared the reduced-dose apixaban (2.5 mg twice daily) with standard VKAs in stable HeartMate 3 patients with TTR > 60%. Aspirin was not mandated. Primary outcomes included thromboembolic events, bleeding, and death.

RESULTS

Forty-four patients were randomized, 21 to apixaban and 23 to VKA. Median age was 55 years (50-64), and 6 were women (14%). The median time from LVAD implantation to randomization was 6 months (range 5-8). Patients were followed for a median of 6 months (2-8). Twenty-five (57%) were transplanted, 12 (27%) were still on treatment, and 5 (11%) had undergone a primary outcome. Event-free survival was similar between groups (hazard ratio [HR] 1.46, 95% confidence interval [CI] 0.64-3.35, p = 0.4, Cox model) as well as Blood product use at transplantation.

CONCLUSIONS

These interim results were obtained after the end of recruitment but before all patients reached the full follow-up duration. The rates of bleeding observed in the apixaban group were below those reported in large international studies without any increase in thrombosis, suggesting that apixaban 2.5 mg twice daily may offer an effective balance between bleeding risk and anticoagulation efficacy. These findings should be interpreted as preliminary and hypothesis-generating.

Apixaban removal during emergency surgery for type A acute aortic dissection: a prospective cohort study

BACKGROUND

Acute type A aortic dissection (ATAAD) has a high mortality, and acute aortic repair is the only curative treatment. In patients treated with factor Xa (FXa) inhibitors, the risk of severe disease-related complications such as cardiac tamponade and hemodynamic shock must be balanced against the potential for severe perioperative bleeding. The aim was to study intraoperative changes in plasma levels of the FXa inhibitor apixaban when using hemoadsorption during acute thoracic aortic repair.

MATERIALS AND METHODS

This is a single-center prospective cohort study. Eight apixaban-treated patients presenting with ATAAD underwent acute thoracic aortic repair with intraoperative hemoadsorption with CytoSorb. Apixaban concentrations were measured at the start of cardiopulmonary bypass (CPB) and after 5, 15, 30, 60, and 90 min of CPB, at CPB weaning, 30 min after CPB weaning and 24 h postoperatively, using ultraperformance liquid chromatography-mass spectrometry (UPLC-MS).

RESULTS

After 30 min of CPB with hemoadsorption, mean apixaban concentration (±SD) was reduced by 59% from 108 (±69) µg/l to 44 (±20) µg/l (P=0.009). There was a further reduction to 37 (±17) µg/l at CPB weaning (P=0.008). Apixaban concentration displayed an increase to 56 (±29) µg/l 24 h postoperatively (P=0.01). In-hospital mortality was 25%. The mean 24H chest tube drainage volume was 621 (±136) ml.

CONCLUSION

Intraoperative hemoadsorption lowers apixaban levels in patients undergoing emergency surgery for ATAAD. Further research is needed to determine its impact on perioperative bleeding complications and mortality.

Hemoadsorption: consensus report of the 30th Acute Disease Quality Initiative workgroup

Adsorption-based extracorporeal therapies have been subject to technical developments and clinical application for close to five decades. More recently, new technological developments in membrane and sorbent manipulation have made it possible to deliver more biocompatible extracorporeal adsorption therapies to patients with a variety of conditions. There are several key rationales based on physicochemical principles and clinical considerations that justify the application and investigation of such therapies as evidenced by multiple ex vivo, experimental and clinical observations. Accordingly, unspecific adsorptive extracorporeal therapies have now been applied to the treatment of a wide array of conditions from poisoning to drug overdoses, to inflammatory states and sepsis, and acute or chronic liver and kidney failure. In response to the rapidly expanding knowledge base and increased clinical evidence, we convened an Acute Disease Quality Initiative consensus conference dedicated to such treatment. The data show that hemoadsorption has clinically acceptable short-term biocompatibility and safety, technical feasibility and experimental demonstration of specified target molecule removal. Pilot studies demonstrate potentially beneficial effects on physiology and larger studies of endotoxin-based hemoadsorption have identified possible target phenotypes for larger randomized controlled trials. Moreover, in a variety of endogenous and exogenous intoxications, removal of target molecules has been confirmed in vivo. However, some studies have raised concerns about harm, or failed to deliver benefits. Thus, despite many achievements, modern hemoadsorption remains a novel and experimental intervention with limited data, and a large research agenda.

Apixaban in bridge to transplant and destination LVAD - rationale and study design: the ApixiVAD trial

AIMS

Use of novel anticoagulation in mechanical circulatory support is controversial. We report the rationale and design of the ApixiVad pilot trial, a pilot study testing the safety of apixaban as an anticoagulant in patients bridged to transplant (BTT) or for destination (DT) with Heartmate 3 (HM3) left ventricular assist device (LVAD).

METHODS AND RESULTS

Apixaban has been used in small non-randomized cohorts in LVAD patients and shown to be effective in ex vivo studies. The ApixiVAD study examines apixaban use in a multicentre, international, open-label, randomized, controlled trial aiming to include 50 BTT or DT HM3 patients with a 1:1 randomization ratio. This event-driven study has a maximum follow-up period of 24 months with interim analysis at 6 months. The primary outcome is death, thromboembolic events and major bleeding, including operative bleeding and immediate transplant outcomes. The secondary outcome focuses on patients' quality of life related to anticoagulation. This investigator-driven pilot study is not powered to determine the non-inferiority of apixaban. An increase in primary outcome in the apixaban group of 20% will be considered a signal of harm.

CONCLUSIONS

A positive outcome in the ApixiVAD study would provide the basis for future, larger, pivotal anticoagulation trials in LVAD patients.

Adsorption Mass Transfer Zone of Vancomycin in Cartridges With Styrene-Divinylbenzene Sorbent

Cartridges for hemoadsorption containing styrene-divinylbenzene sorbent are used for multiple conditions, such as intoxication. The mass transfer zone comprises the extension along the longitudinal span of the cartridge where adsorption occurs. The aim of this experiment is to evaluate the mass transfer zone for vancomycin in the HA380 cartridge. The experiment was carried out twice. A saline solution with vancomycin passed through a HA380-modified cartridge at 100 ml/min in a single-pass fashion. The cartridge had four openings along its longitudinal dimension, at 3, 6, 9, and 12 cm. In both experiments, the collection of aliquots occurred at minute 4, in the four openings and pre- and post-cartridge, and an additional sample from the effluent bag at the end of each experiment. In the second experiment, an additional sampling of the same six sites occurred at minute 14. The sigmoidal shape of the curve for the mass transfer zone of vancomycin was similar to the theoretical one. In experiment one, at minute 4, vancomycin clearance was 98.75 ml/min. In experiment two, vancomycin clearance at minutes 4 and 14 was 93.76 and 93.20 ml/min, respectively. This implies an adequate and optimal design of the HA380 cartridge.

Effective Apixaban removal using hemoadsorption during emergent open-heart surgery: a case report and narrative literature review

BACKGROUND

The management of hemostasis in patients medicated with apixaban (Eliquis) undergoing emergency cardiac surgery is exceedingly difficult. The body's natural elimination pathways for apixaban prove ineffective in emergency situations, and the impact of hemodialysis is limited. The application of Cytosorb® may attenuate the concentration of apixaban, thereby facilitating the stabilization of these patients.

CASE PRESENTATION

An 84-year-old man treated with apixaban, underwent emergency ascending aorta replacement surgery due to an acute type A aortic dissection. To address the challenges induced by apixaban, we integrated Cytosorb® cartridge into the Cardiopulmonary bypass circuit. There was a 63.7% decrease in perioperative apixaban-specific anti-factor Xa activity. The patient's postoperative course was favourable.

CONCLUSION

Hemoadsorption with Cytosorb® may offers a safe and feasible approach for reducing apixaban concentration in emergency cardiac surgery, thereby mitigating the risk of hemorrhagic complications.

Early Goal-Directed Hemostatic Therapy for Severe Acute Bleeding Management in the Intensive Care Unit: A Narrative Review

This is a narrative review of the published evidence for bleeding management in critically ill patients in different clinical settings in the intensive care unit (ICU). We aimed to describe "The Ten Steps" approach to early goal-directed hemostatic therapy (EGDHT) using point-of-care testing (POCT), coagulation factor concentrates, and hemostatic drugs, according to the individual needs of each patient. We searched National Library of Medicine, MEDLINE for publications relevant to management of critical ill bleeding patients in different settings in the ICU. Bibliographies of included articles were also searched to identify additional relevant studies. English-language systematic reviews, meta-analyses, randomized trials, observational studies, and case reports were reviewed. Data related to study methodology, patient population, bleeding management strategy, and clinical outcomes were qualitatively evaluated. According to systematic reviews and meta-analyses, EGDHT guided by viscoelastic testing (VET) has been associated with a reduction in transfusion utilization, improved morbidity and outcome in patients with active bleeding. Furthermore, literature data showed an increased risk of severe adverse events and poor clinical outcomes with inappropriate prophylactic uses of blood components to correct altered conventional coagulation tests (CCTs). Finally, prospective, randomized, controlled trials point to the role of goal-directed fibrinogen substitution to reduce bleeding and the amount of red blood cell (RBC) transfusion with the potential to decrease mortality. In conclusion, severe acute bleeding management in the ICU is still a major challenge for intensive care physicians. The organized and sequential approach to the bleeding patient, guided by POCT allows for rapid and effective bleeding control, through the rational use of blood components and hemostatic drugs, since VET can identify specific coagulation disorders in real time, guiding hemostatic therapy with coagulation factor concentrates and hemostatic drugs with individual goals.

A Contemporary Review of the Use of Extracorporeal CytoSorb® Hemoadsorption Therapy in Patients with Infective Endocarditis

Infective endocarditis (IE) is a rare but severe disease with high morbidity and mortality. Cardiac surgery plays a major role in the contemporary clinical management of IE patients. During cardiac surgery, cardiopulmonary bypass significantly contributes to an increased risk of organ dysfunction and mortality by inducing an acute inflammatory response, vascular endothelial cell injury, impairment of the coagulation cascade, and ischemia-reperfusion injury. During the past decade, the use of extracorporeal hemoadsorption therapy with the CytoSorb® hemoadsorber (CytoSorbents Europe GmbH, Berlin, Germany) has been proposed as an adjuvant therapy to mediate inflammatory responses in IE patients undergoing cardiac surgery with cardiopulmonary bypass. However, there is currently no systematic evaluation of the effect of CytoSorb® hemoadsorption on clinical outcomes such as hemodynamics, organ dysfunction, and mortality in patients with IE. Therefore, in this review, we exclusively discuss contemporary findings concerning the rationale, clinical evidence, and future perspectives for CytoSorb® hemoadsorption therapy in IE patients.

Standardized in vitro bleeding tests in a non-coated novel hybrid prosthesis for frozen elephant trunk demonstrates minimal oozing during full heparinization, supported by clinical data

Introduction

Recent reports have questioned the blood impermeability of the novel frozen elephant trunk (FET) device E-vita Open NEO© (EO-NEO). Therefore, standardized in vitro bleeding tests using porcine heparinized blood were performed, as well as stress testing on the blood tightness of the collar suture line, to investigate this observation.

Material and methods

EO-NEO prostheses were examined in vitro for blood permeability in three test series. Initially, antegrade perfusion with heparinized porcine blood [activated clotting time (ACT) of 500 s, with a 60 min duration] was performed, followed by ante/retrograde testing via the EO-NEO side port. Testing of the collar suture line under a tension of 10 Newton (N) within a suspension device (blood pressure 120 mmHg, ACT of 560 s, 1 min duration) was carried out with the suture material force fiber white (FFWs) yarn, using standard fixation (5 stitches/cm), FFWh yarn in hemostatic fixation (15 stitches/cm), and flow weave yarn (FWYh).

Results

Blood permeability testing of EO-NEO through the prosthetic lumen or via the side port demonstrated minor leakage without statistical difference between the standard and hemostatic suture lines or suture materials used, or positioning on the crimped or tapered portion (p > 0.05). The specific collar anastomosis testing demonstrated leakage volumes of 140 ml/min for FFWs vs. 16 ml/min for FFWh (p = 0.02), vs. 9 ml/min with the FWYh (p = 0.01).

Conclusion

Different blood leakage tests showed minimal oozing and no difference in blood loss through the fabric and different collar suture lines, but unphysiological pressurized retrograde perfusion of the collar region showed significantly less leakage using FWYh and FFWh, prompting production modification of EO-NEO. Clinical results confirmed low blood loss using this novel FET device.

Perioperative hemostatic management of patients with type A aortic dissection

Coagulopathy is common in patients undergoing thoracic aortic repair for Stanford type A aortic dissection. Non-critical administration of blood products may adversely affect the outcome. It is therefore important to be familiar with the pathologic conditions that lead to coagulopathy in complex cardiac surgery. Adequate care of these patients includes the collection of the medical history regarding the use of antithrombotic and anticoagulant drugs, and a sophisticated diagnosis of the coagulopathy with viscoelastic testing and subsequently adapted coagulation therapy with labile and stable blood products. In addition to the above-mentioned measures, intraoperative blood conservation measures as well as good interdisciplinary coordination and communication contribute to a successful hemostatic management strategy.

Intraoperative ticagrelor removal via hemoadsorption during on-pump coronary artery bypass grafting

Objectives

Patients on ticagrelor undergoing urgent cardiac surgery are at high risk for perioperative bleeding complications. We sought to determine whether intraoperative hemoadsorption could remove ticagrelor and lower circulating drug concentrations.

Methods

The hemoadsorption device was incorporated in the cardiopulmonary bypass (CPB) circuit and remained active for the duration of the pump run. Blood samples were collected before and after CPB. The main objective of the current analysis was to compare mean total plasma ticagrelor levels (ng/mL) at baseline with ticagrelor levels obtained at the end of CPB. Plasma ticagrelor levels were measured at a certified outside laboratory (LabConnect). Data are presented as mean ± standard deviation.

Results

A total of 11 patients undergoing urgent coronary artery bypass grafting at 3 institutions were included (mean age, 67.9 ± 9.9 years; 91% male; mean European System for Cardiac Operative Risk Evaluation II of 3.0 ± 3.3%; range, 0.7%-12.4%). Mean intraoperative hemoadsorption duration was 97.1 ± 43.4 minutes with a mean flow rate through the device of 422.9 ± 40.3 mL/min. Mean ticagrelor levels pre-CPB were 103.5 ± 63.8 ng/mL compared with mean post-CPB levels of 34.0 ± 17.5 ng/mL, representing a significant 67.1% reduction (P < .001). Intraoperative integration of the device was simple and safe without any device-related adverse events reported.

Conclusions

This is the first in vivo report demonstrating that intraoperative hemoadsorption can efficiently remove ticagrelor and significantly reduce circulating drug levels. Whether active ticagrelor removal can reduce serious perioperative bleeding in patients undergoing urgent cardiac surgery is currently being evaluated in the double-blinded, randomized Safe and Timely Antithrombotic Removal-Ticagrelor (STAR-T) trial.

Extracorporeal hemoadsorption therapy as a potential therapeutic option for rapid removal of Apixaban in high risk-surgical patients: a case report

BACKGROUND

Apixaban is a non-vitamin K antagonist oral anticoagulant (NOACs) recently emerged as an effective alternative to conventional vitamin K antagonists (VKAs) in the treatment of several thromboembolic disorders. However, in case of overdose or in patients requiring emergency surgery there is a high bleeding rate and severe adverse side effects due to the absence of an antidote. There is promising data from in vitro and clinical studies, that certain antithrombotic agents (that is Rivaroxaban and Ticagrelor) have been successfully removed by the extracorporeal hemoadsorption therapy CytoSorb. Here, we present the case of a patient successfully treated with CytoSorb as a kind of antidote to enable emergency surgery for bilateral nephrostomy.

CASE PRESENTATION

A 82-year-old Caucasian man was admitted to the Emergency Room with acute kidney injury (AKI) in the context of severe bilateral hydroureteronephrosis. The patient's medical history included chronic obstructive pulmonary disease, arterial hypertension, atrial fibrillation (anticoagulated with Apixaban) and a locally advanced prostate adenocarcinoma treated with trans-ureteral resection of the bladder and radiotherapy in the previous months. The indication for a bilateral nephrostomy could not be considered immediately given the major bleeding risk due to Apixaban, which was discontinued and replaced with calciparin. After 36 hours of continuous renal replacement therapy (CRRT), the Apixaban blood level was still elevated and it was decided to install CytoSorb into the running CRRT to accelerate the drug clearance. After 2 hours 30 minutes, there was good reduction of Apixaban from 139 to 72 ng/ml (reduction rate of 48.2%) registered, and this allowed for an easy placement of bilateral nephrostomies without complications. Four days after surgery renal function parameters further normalized, the patient did not require additional dialysis treatments and Apixaban therapy was prescribed again once the patient returned home.

CONCLUSIONS

In this case we report the findings of a patient with post-renal AKI requiring emergency nephrostomy placement while on chronic anticoagulation with Apixaban therapy. Combined treatment with CRRT and CytoSorb was associated with the rapid and effective removal of Apixaban allowing for prompt and urgent surgery while simultaneously ensuring the low risk of bleeding as well as an uneventful post-operative course.

CytoSorb haemoadsorption for removal of apixaban-A proof-of-concept pilot case for a randomized controlled trial

WHAT IS KNOWN AND OBJECTIVE

Emergent cardiac surgery in patients under anticoagulant therapy is still a major point of concern. Recently approved reversal agents are often not available or not suitable in the cardiac surgery setting, and timely discontinuation of the drug is not always feasible. CytoSorb® haemoadsorption therapy has been approved in Europe for intraoperative ticagrelor and rivaroxaban removal during cardiopulmonary bypass (CPB), but thus far the efficacy of CytoSorb® haemoadsorber on other anticoagulants (apixaban, dabigatran, edoxaban) has only been tested in vitro, and some signals of clinical benefits have reported in a few case reports.

CASE SUMMARY

We describe a case of CPB implementation with CytoSorb® in a haemodynamic unstable patient with prosthetic aortic valve endocarditis on apixaban therapy.

WHAT IS NEW AND CONCLUSION

CytoSorb® proved to be effective for removal of apixaban in emergency surgery setting by direct measurements of drug levels before and during CPB circulation.

Removal of Apixaban during Emergency Cardiac Surgery Using Hemoadsorption with a Porous Polymer Bead Sorbent

Background: Patients on direct oral anticoagulants are at high risk of perioperative bleeding complications. We analyzed the results of intraoperative hemoadsorption (HA) in patients undergoing cardiac surgery who were also on concurrent therapy with apixaban. Methods: we included 25 consecutive patients on apixaban who underwent cardiac surgery with the use of cardio-pulmonary bypass (CPB) at three sites. The first 12 patients underwent surgery without hemoadsorption (controls), while the next 13 consecutive patients were operated with the Cytosorb® (Princeton, NJ, USA) device integrated into the CPB circuit (HA group). The primary outcome was perioperative bleeding assessed by the Bleeding Academic Research Consortium (BARC) definition and secondary outcomes included 24 h chest-tube-drainage (CTD) and need for 1-deamino-8-d-arginine-vasopressin (desmopressin (DDAVP)) administration to achieve hemostasis. Results: Preoperative mean daily dose of apixaban was higher in the HA group (8.5 ± 2.4 vs. 5.6 ± 2.2 mg, p = 0.005), while time since last apixaban dose was longer in the controls (1.3 ± 0.9 vs. 0.6 ± 1.2 days, p < 0.001). No BARC-4 bleeding events and no repeat-thoracotomies occurred in the HA group compared with 3 and 1, respectively, in the controls. Postoperative 24 h CTD volume was significantly lower in the HA group (510 ± 152 vs. 893 ± 579 mL, p = 0.03) and there was no need for DDAVP compared to controls, who received an average of 10 ± 13.6 mg (p = 0.01). Conclusions: In patients on apixaban undergoing emergent cardiac surgery, the intraoperative use of hemoadsorption was feasible and safe. Compared to patients operated on without hemoadsorption, BARC-4 bleeding complications did not occur and the need for 24 h CTD and DDAVP was significantly lower.