Continuous renal replacement therapy in patients receiving extracorporeal membrane oxygenation therapy

Methods of continuous renal replacement therapy (CRRT) in extracorporeal membrane oxygenation (ECMO) patients include dedicated central venous cannula (CVC) (vCRRT), in-series with filter connected to ECMO circuit (eCRRT) or in-line with haemodiafilter incorporated within ECMO circuit. We assessed the efficacy and safety of eCRRT versus vCRRT in 20 ECMO-CRRT patients. Average filter lifespan was 42 vs 28 hours and filter runs completing 72hours were 40% vs 13.8% (eCRRT vs vCRRT, respectively). One incidence of ECMO circuit air embolus occurred (vCRRT). eCRRT achieved adequate filtration and increased filter lifespan, and has become our default for ECMO-CRRT if a pre-existing dialysis CVC is not present.

220. The Treatment of Enterococcus Blood Stream Infections in Patients Receiving Extracorporeal Membrane Oxygenation

Background Background: Extracorporeal membrane oxygenation (ECMO) is a growing modality of life support that is subject to a high rate of nosocomial infections. There is a paucity of data to guide treatment for infections on ECMO, which can lead to vastly different practice patterns at different centers. This case series describes the outcomes of patients with Enterococcus bacteremia at a single center. Methods A retrospective chart review was performed on all patients who received ECMO support at a tertiary academic medical center with ECMO capabilities between October 2012 and May 2020 with positive blood cultures for Enterococcus species. Results A total of 10 patients had Enterococcus bacteremia during the study period with E. faecalis (n=7, 70%) more commonly than E. faecium (n=3, 30%). Infections occurred more often in men (n=6, 60%) than women (n=4, 40%) with median age 36 (IQR: 31-42). Infections occured late in the hospitalization (median: 33 days (IQR: 26-59)) and after several weeks on the ECMO circuit (median: 24 days (22-52)). Infections were often polymicrobial (n=5, 50%). There were no cases of infective endocarditis. Infections were treated with 7-14 days of therapy with ampicillin being the most common antibiotic prescribed (n=5, 50%). Four (40%) patients were decannulated before completion of therapy. No patients had cannulas removed due to bacteremia. There were no cases of recurrence. Mortality was 20% in this cohort. Clinical Characteristics of Patients with Enterococcus Bacteremia Conclusion Enterococcus is a common cause of blood stream infections in patients with prolonged courses on ECMO circuit. In this cohort of patients, Enterococcus did not cause any metastatic infections and was generally treated with 7-14 days of antibiotics without recurrence, despite many patients remaining on ECMO for extended periods after clearance. As ECMO use continues to expand, there will need to be more data on treatment outcomes of infections to establish best practices. Disclosures All Authors: No reported disclosures

Continuous renal replacement therapy and extracorporeal membrane oxygenation: implications in the COVID-19 era

The novel severe acute respiratory syndrome coronavirus 2, SARS-CoV-2 (coronavirus Disease 19 (COVID-19)) was identified as the causative agent of viral pneumonias in Wuhan, China in December 2019, and has emerged as a pandemic causing acute respiratory distress syndrome (ARDS) and multiple organ dysfunction. Interim guidance by the World Health Organization states that extracorporeal membrane oxygenation (ECMO) should be considered as a rescue therapy in COVID-19-related ARDS. International registries tracking ECMO in COVID-19 patients reveal a 21%–70% incidence of acute renal injury requiring renal replacement therapy (RRT) during ECMO support. The indications for initiating RRT in patients on ECMO are similar to those for patients not requiring ECMO. RRT can be administered during ECMO via a temporary dialysis catheter, placement of a circuit in-line hemofilter, or direct connection of continuous RRT in-line with the ECMO circuit. Here we review methods for RRT during ECMO, RRT initiation and timing during ECMO, anticoagulation strategies, and novel cytokine filtration approaches to minimize COVID-19’s pathophysiological impact.

COVID-19-Related Acute Respiratory Distress Syndrome in a Pregnant Woman Supported on ECMO: The Juxtaposition of Bleeding in a Hypercoagulable State

A 40-year-old pregnant woman at 28 weeks of gestation was diagnosed with severe acute respiratory failure syndrome (ARDS) due to coronavirus disease 2019 (COVID-19). She had severe hypoxemia despite the use of mechanical ventilation and muscle relaxant infusion. Veno-venous extracorporeal membrane oxygenation (VV-ECMO) was used, and she had a cesarian section while on ECMO support. She developed disseminated intravascular coagulation (DIC) with overt bleeding. This was managed by a multidisciplinary team (MDT) and a change of the ECMO circuit resulted in a dramatic improvement of her coagulation profile. Both the mother and the baby were discharged and went home in good condition.

Evaluation of an ex-vivo neonatal extracorporeal membrane oxygenation circuit on antiepileptic drug sequestration

Antiepileptic dosing information used to manage neonatal patients receiving extracorporeal membrane oxygenation (ECMO) is limited. The objective of this study is to quantify the extent of sequestration of various antiepileptic drugs using an ex-vivo neonatal ECMO circuit. Two neonatal closed-loop ECMO circuits were prepared using a Rotaflow centrifugal pump, custom polyvinylchloride tubing and a Quadrox-i Neonatal membrane oxygenator. After 5 minutes of circuit priming and stabilization with normal saline/albumin or expired human whole blood, single boluses of levetiracetam (200 mg), lacosamide (20 mg), and phenytoin (200 mg) were injected into the circuit. To account for spontaneous drug degradation, two polyvinylchloride beakers were filled with normal saline/albumin or expired human whole blood and equivalent antiepileptic drug doses were prepared. Simultaneous pharmacokinetic samples were collected from the control solution and the pre-centrifugal pump, pre-oxygenator, and post-oxygenator sampling ports from each circuit. Similar drug recovery profiles were observed among the three sampling sites investigated. Percent drug sequestration after a 24-hour circuit flow period was relatively similar between the two different circuits and ranged between 5.5%–13.2% for levetiracetam, 18.4%–22.3% for lacosamide, and 24.5%–30.2% for phenytoin. A comparison at 12 and 24 hours demonstrated similar percent drug sequestration across all three drugs in each circuit. Percent drug sequestrations for levetiracetam and lacosamide were less than 20% and for phenytoin were as high as 30% based on the sampling following single bolus dose administration into a neonatal ECMO circuit. Careful consideration of patient clinical status should be taken in consideration when optimizing antiepileptic therapy in neonates receiving ECMO.

Renal Replacement Therapy for Patients Requiring Extracorporeal Membrane Oxygenation: A Multicenter International Survey

ObjectivesPatients receiving extracorporeal membrane oxygenation (ECMO) often require renal replacement therapy (RRT). Insertion of a dialysis catheter may be challenging in these patients. Direct connection of RRT lines on an ECMO circuit (DCRE) may help circumvent this problem. However, no guidelines exist on this issue, and various types of practices may exist. This study aimed to describe the practice of RTT in patients on ECMO, including the direct connection of RTT lines on the ECMO circuit (DCRE) as well as the perception and concerns related to this technique.DesignInternational surveySetting.Worldwide diffusion via email.Subject.Professionals involved in the management of ECMOInterventions:Respondents’ characteristics were analyzed. Respondents always or often performing RRT via the ECMO circuit were classified in the ECMO group, and those using a dialysis catheter were classified in the DC group. The two groups were compared regarding their characteristics and their practice in ECMO and RRT. Participants were asked about their perceptions of DCRE and actual problems previously encountered. Measurements and Main Results:From March 2019 to October 2019, 298 participants answered the questionnaire from 46 different countries. Only 28% were working in pediatric departments. Among the 165 participants commonly performing RRT in patients on ECMO, 100 (61%) performed mainly RRT via the ECMO circuit, and 65 (39%) performed RRT via DC. Pediatric practice and a longer experience were the only noticeable characteristics of the ECMO group. The most reported fear regarding DCRE was the risk of air embolism (n=84, 28%), but the most encountered problem was unmanageable pressure alarms in RRT devices.ConclusionThe present study showed significant heterogeneity in RRT practices in patients on ECMO. The lower experience of the DC group, the high rates of fears toward DCRE, and pressure alarm issues suggested that protocols and training may overcome reluctance and technical difficulties. Further research may provide data to back specific guidelines. Take-home messageThe present study showed significant heterogeneity in RRT practices in patients on ECMO showing lower experience, fears and pressure alarm issues as barriers for direct connection of RRT lines on ECMO circuit, suggesting needs for protocols, training and specific guidelines.140-character TweetLow experience, fears and pressure alarm issues as barriers for direct connection of RRT lines on ECMO circuit, suggesting needs for protocols, training and specific guidelines.

Transition from Simple V-V to V-A and Hybrid ECMO Configurations in COVID-19 ARDS

In SARS-CoV-2 patients with severe acute respiratory distress syndrome (ARDS), Veno-Venous Extracorporeal Membrane Oxygenation (V-V ECMO) was shown to provide valuable treatment with reasonable survival in large multi-centre investigations. However, in some patients, conversion to modified ECMO support forms may be needed. In this single-centre retrospective registry, all consecutive patients receiving V-V ECMO between 1 March 2020 to 1 May 2021 were included and analysed. The patient cohort was divided into two groups: those who remained on V-V ECMO and those who required conversion to other modalities. Seventy-eight patients were included, with fourteen cases (18%) requiring conversions to veno-arterial (V-A) or hybrid ECMO. The reasons for the ECMO mode configuration change were inadequate drainage (35.7%), inadequate perfusion (14.3%), myocardial infarction (7.1%), hypovolemic shock (14.3%), cardiogenic shock (14.3%) and septic shock (7.1%). In multivariable analysis, the use of dobutamine (p = 0.007) and a shorter ICU duration (p = 0.047) predicted the conversion. The 30-day mortality was higher in converted patients (log-rank p = 0.029). Overall, only 19 patients (24.4%) survived to discharge or lung transplantation. Adverse events were more common after conversion and included renal, cardiovascular and ECMO-circuit complications. Conversion itself was not associated with mortality in the multivariable analysis. In conclusion, as many as 18% of patients undergoing V-V ECMO for COVID-19 ARDS may require conversion to advanced ECMO support.

Can Heparin-Coated ECMO Cannulas Induce Thrombocytopenia in COVID-19 Patients?

Extracorporeal membrane oxygenation (ECMO) is often used in the management of COVID-19-related severe respiratory failure. We report the first case of a patient with COVID-19-related ARDS on ECMO support who developed symptoms of heparin-induced thrombocytopenia (HIT) in the absence of heparin therapy. A low platelet count of 61 G/L was accompanied by the presence of circulating HIT antibodies 12 days after ECMO initiation. Replacement of the ECMO system including cannulas resulted in the normalization of the platelet count. However, the clinical situation did not improve, and the patient died 9 days later. Careful consideration of anticoagulant therapy and ECMO circuit, as well as routine HIT antibody testing, may prevent a fatal course in ECMO-supported COVID-19 patients.

Managing Harlequin Syndrome in VA-ECMO – do not forget the right ventricle

Harlequin Syndrome (also known as North-South Syndrome) is a complication of veno-arterial extracorporeal membrane oxygenation (V-A ECMO) that can occur when left ventricular function starts to recover. While most commonly due to continued impaired gas exchange in the lungs, we present a case caused by right ventricular dysfunction, successfully managed by conversion of the ECMO circuit to a veno-veno-arterial (VV-A) configuration.