Single-center experience of extracorporeal membrane oxygenation mainly anticoagulated with nafamostat mesilate

Comparison of regional citrate anticoagulation and nafamostat mesylate anticoagulation during plasma exchange for children at high bleeding risk: a retrospective study

BACKGROUND

There is currently no established optimal anticoagulation protocol for plasma exchange (PE) in pediatric patients at a high risk of bleeding. Therefore, we aimed to evaluate the efficacy and safety of regional citrate anticoagulation (RCA) and nafamostat mesylate (NM) for PE anticoagulation in this patient group.

METHODS

This retrospective study analyzed data from 66 children with high bleeding risk who underwent PE in the Pediatric Intensive Care Unit of Hunan Children's Hospital between June 2018 and January 2023. Patients were divided into two groups: RCA-PE (n = 45) and NM-PE (n = 21), and filter performance and adverse reaction rates were compared. Statistical analysis utilized SPSS 25.0, comprising two-sample t-tests, chi-square or Fisher's exact tests, and Mann-Whitney U tests, as appropriate. Data visualization was performed using ggplot2 in R-studio. P < 0.05 was considered statistically significant.

RESULTS

No statistically significant differences were found between the two groups in initial transmembrane pressure (TMP) [17.0 (14.0, 21.5) mmHg vs. 16.0 (14.0, 19.5) mmHg, P = 0.614], maximum TMP [46.0 (42.0, 49.5) mmHg vs. 43.0 (41.5, 49.5) mmHg, P = 0.689], and final TMP [40.0 (35.5, 45.0) mmHg vs. 38.0 (35.0, 42.0) mmHg, P = 0.298]. Filter grade distribution and bleeding events also showed no statistically significant difference between the groups. However, the NM-PE group had significantly lower overall adverse reaction and metabolic alkalosis rates (both P < 0.05) compared to the RCA-PE group.

CONCLUSIONS

NM demonstrates similar efficacy but superior safety compared with RCA, making it a more suitable anticoagulation strategy for children with high bleeding risk. Study limitations include single-center design, selection bias, and uncertain NM dosage.

Heparin Resistance in Patients Receiving Extracorporeal Membrane Oxygenation: A Review

Heparin resistance (HR) in patients on extracorporeal membrane oxygenation (ECMO) exacerbates bleeding and thrombogenesis. Thus far, there is no universal definition of what this condition entails and no unified strategy for assessing heparin's efficacy in ECMO patients. The most frequent discrepancy when it comes to defining HR is the difference in the reported doses: units per day (U/d) or per kilogram per hour (U/kg/h). Another disagreement arises with regard to the various methods of measuring unfractionated heparin (UFH) efficacy. Due to numerous processes that begin with ECMO initiation, including protein layer formation on the surface of circuits, the recruitment of immune cells, the activation of complement and contact activation systems, and platelets, assessing pure antithrombin consumption is complicated. Moreover, there is an alternative anticoagulation procedure performed by a serine protease inhibitor named heparin cofactor II, which could also contribute to heparin consumption. Considering simultaneously launched processes of inflammation and thrombogenesis in response to contact with artificial surfaces on ECMO, we listed the possible mechanisms contributing to additional antithrombin consumption. The effect of the flow on the platelets' activation and von Willebrand factor (vWF) assembly was also described. We reviewed the scientific literature from PubMed and Embase to identify possible definitions of heparin resistance during ECMO treatment among pediatric and adult cohorts. We identified 13 records describing different approaches to assessing HR and described our vision of delineating HR on ECMO.

Amniotic fluid embolism rescued using venoarterial extracorporeal membrane oxygenation without initial anticoagulation: A case report and literature review

RATIONALE

Amniotic fluid embolism (AFE) is a fatal obstetric condition that often rapidly leads to severe respiratory and circulatory failure. It is complicated by obstetric disseminated intravascular coagulation (DIC) with bleeding tendency; therefore, the introduction of venoarterial extracorporeal membrane oxygenation (VA-ECMO) is challenging. We report the case of a patient with AFE requiring massive blood transfusion, rescued using VA-ECMO without initial anticoagulation.

PATIENTS CONCERNS

A 39-year-old pregnant patient was admitted with a complaint of abdominal pain. An emergency cesarean section was performed because a sudden decrease in fetal heart rate was detected in addition to DIC with hyperfibrinolysis. Intra- and post-operatively, the patient had a bleeding tendency and required massive blood transfusions. After surgery, the patient developed lethal respiratory and circulatory failure, and VA-ECMO was introduced.

DIAGNOSIS

Based on the course of the illness and imaging findings, the patient was diagnosed with AFE.

INTERVENTIONS

By controlling the bleeding tendency with a massive transfusion and tranexamic acid administration, using an antithrombotic ECMO circuit, and delaying the initiation of anticoagulation and anti-DIC medication until the bleeding tendency settled, the patient was managed safely on ECMO without complications.

OUTCOMES

By day 5, both respiration and circulation were stable, and the patient was weaned off VA-ECMO. Mechanical ventilation was discontinued on day 6. Finally, she was discharged home without sequelae.

LESSONS

VA-ECMO may be effective to save the lives of patients who have AFE with lethal circulatory and respiratory failure. For safe management without bleeding complications, it is important to start VA-ECMO without initial anticoagulants and to administer anticoagulants and anti-DIC drugs after the bleeding tendency has resolved.

Anticoagulants in adult extracorporeal membrane oxygenation: alternatives to standardized anticoagulation with unfractionated heparin

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is a vital technique for severe respiratory or heart failure patients. Bleeding and thrombotic events are common during ECMO and negatively impact patient outcomes. Unfractionated heparin is the primary anticoagulant, but its adverse effects limit its use, necessitating alternative anticoagulants.

OBJECTIVE

Review available alternative anticoagulants for adult ECMO patients. Explore potential novel anticoagulants for future ECMO use. Aim to reduce complications (bleeding and thrombosis) and improve safety and efficacy for critically ill ECMO patients.

METHODS

Comprehensive literature review of existing and emerging anticoagulants for ECMO.

RESULTS

Identified a range of alternative anticoagulants beyond unfractionated heparin. Evaluated their potential utility in mitigating ECMO-related complications.

CONCLUSION

Diverse anticoagulant options are available and under investigation for ECMO. These alternatives may enhance patient safety and outcomes during ECMO support. Further research and clinical studies are warranted to determine their effectiveness and safety profiles.

Anticoagulation strategies in patients with extracorporeal membrane oxygenation: A network meta-analysis and systematic review

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) plays an important role in providing temporary life support for patients with severe cardiac or pulmonary failure, but requires strict anticoagulation and monitoring. This network meta-analysis systematically explored the most effective anticoagulation and monitoring strategies for patients receiving ECMO.

METHODS

MEDLINE, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials were searched up to January 31, 2023, for studies comparing unfractionated heparin (UFH), argatroban (Arg), bivalirudin (Biv), and/or nafamostat mesylate (NM) in patients receiving ECMO. The primary outcomes included device-related thrombosis, patient-related thrombosis, and major bleeding events. The secondary outcomes included ECMO survival, ECMO duration, and in-hospital mortality.

RESULTS

A total of 2522 patients from 23 trials were included in the study. Biv was associated with a decreased risk of device-related thrombosis (odd ratio [OR] 0.51, 95% confidence interval [CI]: 0.33-0.84) compared with UFH, whereas NM (OR 2.2, 95% CI: 0.24-65.0) and Arg (OR 0.92, 95% CI: 0.43-2.0) did not reduce the risk of device-related thrombosis compared with UFH. Biv was superior to Arg in decreasing the risk of device-related thrombosis (OR 0.14, 95% CI: 0.03-0.51). Biv reduced the risk of patient-related thrombosis compared with UFH (OR 0.44, 95% CI: 0.18-0.85); NM (OR 0.65, 95% CI: 0.14-3.3) and Arg (OR 3.1, 95% CI: 0.94-12.0) did not decrease risk of patient-related thrombosis compared with UFH. No significant difference was observed in the risk of major bleeding between three alternatives and UFH: Biv (OR 0.54, 95% CI: 0.23-1.3), Arg (OR 1.3, 95% CI: 0.34-5.8), and NM (OR 0.60, 95% CI: 0.13-2.6). NM showed a reduced risk of in-hospital mortality compared with UFH (OR 0.27, 95% CI: 0.091-0.77), whereas Arg (OR 0.43, 95% CI: 0.15-1.2) and Biv (OR 0.75, 95% CI: 0.52-1.1) did not decrease risk of in-hospital mortality.

CONCLUSIONS

Compared with UFH and Arg, Biv reduces the risk of thrombosis and appears to be a better choice for patients requiring ECMO. NM was associated with a reduced risk of in-hospital mortality.

Application of nafamostat mesylate for anticoagulation in hemoperfusion therapy in patients with bromadiolone poisoning: Case reports

Bromadiolone, as a second-generation coumarin anticoagulant rodenticide, may accidently cause harm to humans and non-target animals when overused or misused due to its high toxicity and long-lasting effects. In some severe cases such as the presence of active bleeding, treatment should involve the administration of hemoperfusion therapy. Nafamostat mesylate is a synthesized protease inhibitor that inhibits most factors in the coagulation process, preventing clotting and ensuring smooth blood flow during the procedure. Nafamostat mesylate helps maintain the efficacy and safety of hemoperfusion treatment. Despite its wide application in Japan, the clinical practice and research of nafamostat mesylate are limited in China, especially for patients undergoing maintenance hemodialysis. This paper reports two cases of bromadiolone poisoning and describes the treatment procedure and therapeutic effect of anticoagulation in hemoperfusion therapy with nafamostat mesylate.

Effects of shorter activated coagulation time on hemorrhage during venoarterial extracorporeal membrane oxygenation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has been used for decades, but optimal anticoagulation control remains unknown. This study aimed to compare shorter target activated coagulation time (ACT) criteria with the usual target ACT criteria in terms of complications.

METHODS

We retrospectively identified patients who received ECMO between 1 January 2013 and 31 December 2018 in an acute tertiary care hospital. Patients were divided into two groups: (I) those whose target ACT was 160-180 sec and (II) those whose target ACT was 180-220 sec. Cox proportional hazard models and Fine-Gray models adjusted for propensity score to account for the competing risk of death were used to compare the incidence of hemorrhage during ECMO between the groups.

RESULTS

We identified 74 patients, 25 of whom were managed with target ACT 160-180 sec, and 49 of whom were managed with target ACT 180-220 sec. In crude analysis, the proportions of patients with hemorrhage in the under 180-sec group were significantly more than those in the over 180-sec group [60.0% (15/25) vs. 28.6% (14/49), p = 0.009]. Shorter target ACT was not associated with hemorrhage during ECMO in either Cox regression (hazard ratio, 1.67; 95% confidence interval, 0.59-4.80; p = 0.336) or Fine-Gray model (hazard ratio, 1.58; 95% confidence interval, 0.64-3.91; p = 0.324).

CONCLUSIONS

The shorter ACT target was not associated with improved hemorrhage and inappropriate coagulation than the usual target ACT criteria. This study is the first to compare the ACT target of patients with ECMO.

Anticoagulation with nafamostat mesilate during extracorporeal life support

Nafamostat mesylate (NM) affects coagulation and fibrinolysis and impedes obesity-associated protein demethylase activity, which regulates Na+/K+ transport properties and the NF-κB signaling pathway. NM significantly decreases macrophage, neutrophil, and T lymphocyte infiltration, thereby reducing inflammation and apoptosis after reperfusion and promoting recovery in patients with severe conditions such as near-fatal asthma and cardiac arrest. Extracorporeal life support (ECLS) devices are used for cardiac and/or pulmonary support as a bridge to recovery, decision, surgery, or transplant in patients with refractory cardio-circulatory or respiratory diseases and provide essential opportunities for organ support and patient survival. However, they can lead to some potential adverse events such as hemorrhage and thrombosis. NM provides a sustained innate immune response of coagulation and anti-inflammation in extracorporeal circuits, principally due to its activation of the contact and complement systems. Heparin is the main anticoagulant used in extracorporeal circuits; however, it may cause massive bleeding and heparin-induced thrombocytopenia. Although no antidote is available, NM has a very short half-life of approximately 8-10 min and might have positive effects on patients who require coagulation and anti-inflammation. NM has been used for anticoagulation in continuous renal replacement therapy, extracorporeal membrane oxygenation, hemodialysis, and left ventricular assist devices. In this review, we focused on the pharmacology, monitoring parameters, and considerations for the special use of NM in patients receiving ECLS. Our findings suggest that systemic anticoagulation with NM during ECLS might be a feasible and safe alternative with several advantages for critically ill patients with high-risk bleeding and might improve their prognosis.

Evaluation of clinical outcomes in patients treated with heparin or direct thrombin inhibitors during extracorporeal membrane oxygenation: a systematic review and meta-analysis

BACKGROUND

The number of patients treated with extracorporeal membrane oxygenation (ECMO) devices is increasing. Anticoagulation therapy is crucial to prevent thrombosis during ECMO therapy. Predominantly, heparin has been used as primary anticoagulant but direct thrombin inhibitors (DTI) have been established as alternatives. The aim of this systematic review and meta-analysis was to evaluate clinical outcomes in patients treated with heparin compared to different DTI during ECMO.

METHODS

A systematic search was conducted. Full scientific articles were sought for inclusion if heparin anticoagulation was compared to DTI (argatroban/bivalirudin) in ECMO patients. Risk of bias was assessed by Newcastle Ottawa scale. Primary endpoint was in-hospital mortality. Bleeding events, thrombotic events, hours of ECMO support, days of hospital stay, percentage of time within therapeutic range and time to therapeutic range were extracted from full texts as secondary endpoints. Results were presented as Forrest-plots. GRADE was used for confidence assessment in outcomes.

RESULTS

Systematic search identified 4.385 records, thereof 18 retrospective studies for a total of 1942 patients, complied with the predefined eligibility criteria:15 studies investigated bivalirudin and 3 studies investigated argatroban versus heparin. Risk of bias was high for most studies. In-hospital mortality, major bleeding events and pump-related thrombosis were less frequent in DTI group as compared to heparin [mortality-OR 0.69, 95% CI 0.54-0.86; major bleeding-OR 0.48, 95% CI 0.29-0.81; pump thrombosis-OR 0.55, 95% CI 0.40-0.76]. Additionally, percentage of time within therapeutic range was higher for DTI [SMD 0.54, 95% CI 0.14-0.94]. GRADE approach revealed a very low level of certainty for each outcome.

CONCLUSION

In this meta-analysis, DTI and especially bivalirudin showed beneficial effects on clinical outcomes in ECMO patients as compared to heparin. However, due to the lack of randomized trials, certainty of evidence is low.

TRIAL REGISTRATION

This systematic review and meta-analysis was prospectively registered at PROSPERO data base (reference number CRD42021237252 ).

Use of nafamostat mesilate for anticoagulation during extracorporeal membrane oxygenation: A systematic review

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) represents an advanced option for supporting refractory respiratory and/or cardiac failure. Systemic anticoagulation with unfractionated heparin (UFH) is routinely used. However, patients with bleeding risk and/or heparin-related side effects may necessitate alternative strategies: among these, nafamostat mesilate (NM) has been reported.

METHODS

We conducted a systematic literature search (PubMed and EMBASE, updated 12/08/2021), including all studies reporting NM anticoagulation for ECMO. We focused on reasons for starting NM, its dose and the anticoagulation monitoring approach, the incidence of bleeding/thrombosis complications, the NM-related side effects, ECMO weaning, and mortality.

RESULTS

The search revealed 11 relevant findings, all with retrospective design. Of these, three large studies reported a control group receiving UFH, the other were case series (n = 3) or case reports (n = 5). The main reason reported for NM use was an ongoing or high risk of bleeding. The NM dose varied largely as did the anticoagulation monitoring approach. The average NM dose ranged from 0.46 to 0.67 mg/kg/h, but two groups of authors reported larger doses when monitoring anticoagulation with ACT. Conflicting findings were found on bleeding and thrombosis. The only NM-related side effect was hyperkalemia (n = 2 studies) with an incidence of 15%-18% in patients anticoagulated with NM. Weaning and survival varied across studies.

CONCLUSION

Anticoagulation with NM in ECMO has not been prospectively studied. While several centers have experience with this approach in high-risk patients, prospective studies are warranted to establish the optimal space of this approach in ECMO.

The role of nafamostat mesilate as a regional anticoagulant during extracorporeal membrane oxygenation

BACKGROUND

Anticoagulation during extracorporeal membrane oxygenation (ECMO) usually is required to prevent thrombosis. The aim of this study was to investigate the usefulness of nafamostat mesilate (NM) as a regional anticoagulant during veno-arterial ECMO (VA-ECMO) treatment.

METHODS

We retrospectively reviewed the medical records of 16 patients receiving VA-ECMO and NM from January 2017 to June 2020 at Haeundae Paik Hospital. We compared clinical and laboratory data, including activated partial thromboplastin time (aPTT), which was measured simultaneously in patients and the ECMO site, to estimate the efficacy of regional anticoagulation.

RESULTS

The median patient age was 68.5 years, and 56.3% of patients were men. Cardiovascular disease was the most common primary disease (75.0%) requiring ECMO treatment, followed by respiratory disease (12.5%). The median duration of ECMO treatment was 7.5 days. Among 16 patients, seven were switched to NM after first using heparin as an anticoagulation agent, and nine received only NM. When comparing aPTT values in the NM group between patients and the ECMO site, that in patients was significantly lower than that at the ECMO site (73.57 vs. 79.25 seconds; P=0.010); in contrast, no difference was observed in the heparin group.

CONCLUSIONS

NM showed efficacy as a regional anticoagulation method by sustaining a lower aPTT value compared to that measured at the ECMO site. NM should be considered as a safer regional anticoagulation method in VA-ECMO for patients at high risk of bleeding.

New Trends, Advantages and Disadvantages in Anticoagulation and Coating Methods Used in Extracorporeal Life Support Devices

The use of extracorporeal life support (ECLS) devices has significantly increased in the last decades. Despite medical and technological advancements, a main challenge in the ECLS field remains the complex interaction between the human body, blood, and artificial materials. Indeed, blood exposure to artificial surfaces generates an unbalanced activation of the coagulation cascade, leading to hemorrhagic and thrombotic events. Over time, several anticoagulation and coatings methods have been introduced to address this problem. This narrative review summarizes trends, advantages, and disadvantages of anticoagulation and coating methods used in the ECLS field. Evidence was collected through a PubMed search and reference scanning. A group of experts was convened to openly discuss the retrieved references. Clinical practice in ECLS is still based on the large use of unfractionated heparin and, as an alternative in case of contraindications, nafamostat mesilate, bivalirudin, and argatroban. Other anticoagulation methods are under investigation, but none is about to enter the clinical routine. From an engineering point of view, material modifications have focused on commercially available biomimetic and biopassive surfaces and on the development of endothelialized surfaces. Biocompatible and bio-hybrid materials not requiring combined systemic anticoagulation should be the future goal, but intense efforts are still required to fulfill this purpose.

Trends in Extracorporeal Membrane Oxygenation Application and Outcomes in Korea

The use of extracorporeal membrane oxygenation (ECMO) is increasing despite the limited evidence in survival benefit. This study aimed to analyze the changes of in-hospital mortality, medical costs, and other outcomes in ECMO therapy. We used 2004-2017 data from a nationwide healthcare administrative claims database in Korea. Overall, 14,775 ECMO procedures were performed in 14,689 patients at 112 hospitals. We found a 170-fold and a 334-fold increase in the number of ECMO procedures and related costs, respectively. For indications, the performance of ECMO for heart or lung transplantation and respiratory failure increased, whereas that for cardiovascular surgery decreased. The duration of ECMO increased from a median of 3 days (IQR, 2-5 days) in 2004 to 4 days (IQR, 2-9 days) in 2017. The overall in-hospital mortality rate was 68.6%, and this improved over time, especially for lung transplantation and respiratory failure patients. Bleeding-related complications and the transfusion amount also decreased. Hospitals with higher case volume showed better survival outcomes. The median cost per procedure and per day was 26,538 USD (IQR, 14,646-47,862 USD) and 1,560 USD (IQR, 903-2,929 USD), respectively, and increased with time. A trend toward greater resource use and better outcomes requires additional cost-effective analysis based on indications.

Preventing thrombosis in a COVID-19 patient by combinatorial therapy with nafamostat and heparin during extracorporeal membrane oxygenation

Background

Extracorporeal membrane oxygenation (ECMO) can be life-saving in cases of coronavirus disease (COVID-19); however, circuit thrombosis is a complication. This report describes a COVID-19 patient treated with nafamostat and heparin to prevent circuit thrombosis during ECMO support.

Case presentation

A 63-year-old man was transferred to our hospital with respiratory failure due to COVID-19 pneumonia. He was provided venous-venous ECMO to maintain oxygenation. During ECMO support, occlusive circuit thrombosis developed despite systemic anticoagulation therapy with heparin. He was subsequently administered combination therapy with nafamostat and heparin. Although the combination therapy could prevent circuit thrombosis, it was converted to heparin monotherapy because of hyperkalemia and hemothorax. After tracheostomy and a gradual improvement in oxygenation, ECMO was discontinued. He was transferred to another hospital for further rehabilitation.

Conclusion

Combination therapy with nafamostat and heparin can prevent circuit thrombosis during ECMO. However, bleeding can still develop with this combination therapy during ECMO.

Nafamostat mesylate attenuates the pathophysiologic sequelae of neurovascular ischemia

Nafamostat mesylate, an apparent soi-disant panacea of sorts, is widely used to anticoagulate patients undergoing hemodialysis or cardiopulmonary bypass, mitigate the inflammatory response in patients diagnosed with acute pancreatitis, and reverse the coagulopathy of patients experiencing the commonly preterminal disseminated intravascular coagulation in the Far East. The serine protease inhibitor nafamostat mesylate exhibits significant neuroprotective effects in the setting of neurovascular ischemia. Nafamostat mesylate generates neuroprotective effects by attenuating the enzymatic activity of serine proteases, neuroinflammatory signaling cascades, and the endoplasmic reticulum stress responses, downregulating excitotoxic transient receptor membrane channel subfamily 7 cationic currents, modulating the activity of intracellular signal transduction pathways, and supporting neuronal survival (brain-derived neurotrophic factor/TrkB/ERK1/2/CREB, nuclear factor kappa B. The effects collectively reduce neuronal necrosis and apoptosis and prevent ischemia mediated disruption of blood-brain barrier microarchitecture. Investigational clinical applications of these compounds may mitigate ischemic reperfusion injury in patients undergoing cardiac, hepatic, renal, or intestinal transplant, preventing allograft rejection, and treating solid organ malignancies. Neuroprotective effects mediated by nafamostat mesylate support the wise conduct of randomized prospective controlled trials in Western countries to evaluate the clinical utility of this compound.