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Veno-venous extracorporeal membrane oxygenation is increasingly used for severe but potentially reversible acute respiratory failure in adults; however, there are limited data regarding long-term morbidity. At our institution, most patients requiring veno-venous extracorporeal membrane oxygenation have been followed up by a single physician. Our primary aim was to describe the serial long-term morbidity for respiratory, musculoskeletal and psychological functioning. A retrospective audit of inpatient and outpatient medical records was conducted. A total of 125 patients treated with veno-venous extracorporeal membrane oxygenation for primary respiratory failure were included. The patients were young (mean (standard deviation) age 43.7 (4.1) years), obese (mean (standard deviation) body mass index 30.8 (10.4) kg/m2), and mostly were male (59%). Most patients (60%) had no comorbidities. The survival rate to discharge was 70%, with body mass index and the number of comorbidities being independent predictors of survival on multiple logistic regression analysis. Over half (57%) of the Australian survivors had regular outpatient follow-up. They had a median of three reviews (range 1–9) over a median of 11.8 months (range 1.5-79) months. Breathlessness and weakness resolved in most within six months, with lung function abnormalities taking longer to resolve. Over half (60%) returned to employment within six months of discharge. Over a quarter (29%) displayed symptoms of anxiety, depression or post-traumatic stress disorder. [ABSTRACT FROM AUTHOR]

Background Transcatheter aortic valve implantation (TAVI) can cause profound haemodynamic perturbation in the peri-operative period. Veno-arterial extracorporeal membrane oxygenation (ECMO) can be used to provide cardiorespiratory support during this time, either prophylactically or emergently. Method 100 TAVI procedures were performed between 2009 and 2013 in our institution. ECMO was used in 11 patients, including eight prophylactic and three rescue cases. Rescue ECMO was required for ventricular fibrillation after valvuloplasty, and aortic annulus rupture. The criteria for prophylactic ECMO included heart failure requiring stabilisation pre-TAVI, haemodynamic instability with balloon aortic valvuloplasty performed to improve heart function pre-TAVI, moderate or severe left and/or right ventricular failure, or borderline haemodynamics at procedure. Differences in preoperative characteristics and postoperative outcomes between ECMO and non-ECMO TAVI patients were compared, and significant results were further assessed controlling for EuroSCORE. Results Compared to TAVI patients who did not require ECMO, ECMO patients had significantly higher mean EuroSCORE (51 vs. 30%, p < .05). Postoperative outcomes, however, were largely comparable between the two groups. All-cause mortality occurred in nil prophylactic ECMO patients, one rescue ECMO patient, and two non-ECMO patients. The difference in mortality between ECMO and non-ECMO patients was not significantly different (9 vs. 2%; p > .05). ECMO patients were more likely to develop acute renal failure than non-ECMO patients (36 vs. 8%, p < .05), which was most likely due to haemodynamic collapse and end-organ dysfunction in patients that required ECMO rescue. Conclusions Instituting prophylactic ECMO in selected very high-risk patients may help avoid consequences of intra-operative complications and the need for emergent rescue ECMO. [ABSTRACT FROM AUTHOR]

Haemolysis, thrombosis and haemorrhage are well-documented complications of extracorporeal membrane oxygenation. This case report outlines an unusual case of haemolysis, thought secondary to a large mobile thrombus in the inferior vena cava. [ABSTRACT FROM AUTHOR]

Objective: The use of extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrests (OHCA) has increased dramatically over the past decade. ECPR is resource intensive and costly, presenting challenges for policymakers. We sought to review the cost-effectiveness of ECPR compared with conventional cardiopulmonary resuscitation (CCPR) in OHCA.Methods: We searched Medline, Embase, Tufts CEA registry and NHS EED databases from database inception to 2021 or 2015 for NHS EED. Cochrane Covidence was used to screen and assess studies. Data on costs, effects and cost-effectiveness of included studies were extracted by two independent reviewers. Costs were converted to USD using purchasing power parities (OECD, 2022).1 The Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist (Husereau et al., 2022)2 was used for reporting quality and completeness of cost-effectiveness studies; the review was registered on PROSPERO, and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.Results: Four studies met the inclusion criteria; three cost-effectiveness studies reported an incremental cost-effectiveness ratio (ICER) for OHCA compared with conventional care, and one reported the mean operating cost of ECPR. ECPR was more costly, accrued more life years (LY) and quality-adjusted life years (QALYs) than CCPR and was more cost-effective when compared with CCPR and other standard therapies. Overall study quality was rated as moderate.Conclusion: Few studies have examined the cost-effectiveness of ECPR for OHCA. Of those, ECPR for OHCA was cost-effective. Further studies are required to validate findings and assess the cost-effectiveness of establishing a new ECPR service or alternate ECPR delivery models. [ABSTRACT FROM AUTHOR]

Refractory out-of-hospital cardiac arrest (OHCA) has a very poor prognosis, with survival rates at around 10%. Extracorporeal membrane oxygenation (ECMO) for patients in refractory arrest, known as ECPR, aims to provide perfusion to the patient whilst the underlying cause of arrest can be addressed. ECPR use has increased substantially, with varying survival rates to hospital discharge. The best outcomes for ECPR occur when the time from cardiac arrest to implementation of ECPR is minimised. To reduce this time, systems must be in place to identify the correct patient, expedite transfer to hospital, facilitate rapid cannulation and ECMO circuit flows. We describe the process of activation of ECPR, patient selection, and the steps that emergency department clinicians can utilise to facilitate timely cannulation to ensure the best outcomes for patients in refractory cardiac arrest. With these processes in place our survival to hospital discharge for OHCA patients is 35%, with most patients having a good neurological function. [ABSTRACT FROM AUTHOR]

In recent years, extracorporeal membrane oxygenation has become increasingly common in the treatment of in-hospital cardiac arrest in non-cardiac surgery patients. This includes cardiac arrest secondary to perioperative anaphylactic shock refractory to standard advanced life support protocols, which is a rare but catastrophic event associated with significant mortality. Neuromuscular blocking drugs are most commonly implicated in perioperative anaphylaxis, with rocuronium playing a major role. In this article, we report two cases of young and otherwise fit and well patients who experienced a perioperative arrest secondary to rocuronium anaphylaxis before elective surgery; both patients did not respond to conventional advanced life support, but survived neurologically intact after institution of urgent veno-arterial extracorporeal membrane oxygenation. [ABSTRACT FROM AUTHOR]

Abstract Peripheral veno-arterial extra corporeal membrane oxygenation (VA-ECMO) is an established technique for short-to-medium support of patients with severe cardiac failure. However, in patients with concomitant respiratory failure, the residual native circulation will provide deoxygenated blood to the upper body, and may cause differential hypoxemia of the heart and brain. In this paper, we present a general computational framework for the identification of differential hypoxemia risk in VA-ECMO patients. A range of different VA-ECMO patient scenarios for a patient-specific geometry and vascular resistance were simulated using transient computational fluid dynamics simulations, representing a clinically relevant range of values of stroke volume and ECMO flow. For this patient, regardless of ECMO flow rate, left ventricular stroke volumes greater than 28 mL resulted in all aortic arch branch vessels being perfused by poorly-oxygenated systemic blood sourced from the lungs. The brachiocephalic artery perfusion was almost entirely derived from blood from the left ventricle in all scenarios except for those with stroke volumes less than 5 mL. Our model therefore predicted a strong risk of differential hypoxemia in nearly all situations with some residual cardiac function for this combination of patient geometry and vascular resistance. This simulation highlights the potential value of modelling for optimising ECMO design and procedures, and for the practical utility for personalised approaches in the clinical use of ECMO. [ABSTRACT FROM AUTHOR]

Objective: To describe on‐scene times for out‐of‐hospital cardiac arrests (OHCA) transferred to hospital, the number of these that were extracorporeal cardiopulmonary resuscitation (ECPR) eligible and potential association between end‐tidal carbon dioxide (ETCO2) and survival so as to inform planned interventional studies. Methods: Prospective cohort study of all OHCA, of suspected medical cause, where resuscitation was commenced and who were transported to participating hospitals from October 2020 to May 2021. Results: One hundred and forty‐nine OHCA were included. Forty‐four (30%) patients survived to hospital discharge. Eighteen (8%) met ECPR inclusion criteria. Median on‐scene time was 33 min (interquartile range [IQR] 24–44). Initial hospital ETCO2 for non‐survivors was 35 mmHg (IQR 19–50), survivors 36 mmHg (IQR 33–45); P = 0.215. No patient with an ETCO2 less than 20 mmHg on hospital arrival to survived to hospital discharge. Conclusions: Average on‐scene time did not differ on survivorship. A small number of transferred patients with OHCA were ECPR eligible. ETCO2 less than 20 mmHg portends adverse prognosis. Our data will be used for future interventional studies. [ABSTRACT FROM AUTHOR]

Purpose: Extracorporeal membrane oxygenation (ECMO) is increasingly being used to support critically ill patients with severe cardiac and/or respiratory failure. It has been claimed that the resulting haemodynamic alterations, particularly in venoarterial ECMO, mean that enteral feeding is unsafe and/or poorly tolerated. This study aims to investigate this question and to identify any barriers to optimal nutrition. Methods: Data were retrospectively collected for 86 patients who received ECMO between January 2007 and July 2012 in a tertiary critical care unit/ECMO referral centre. All were fed using existing protocols that emphasise early enteral feeding in preference over parenteral or delayed enteral nutrition. Results: Thirty-one patients required ECMO for cardiac failure, and all of these received venoarterial ECMO; the remainder received venovenous ECMO. Enteral feeds started for all patients at average 13.1 h [standard deviation (SD) 16.7 h] after ICU admission, reaching goal rate on day 2.6 (SD 1.4). Thirty-three patients experienced significant feeding intolerance during the first 5 days, but of these 20 were managed effectively with prokinetic medications; 18 required parenteral nutrition to supplement inadequately tolerated tube feeds. Intolerance did not differ between ECMO modes. Overall patients tolerated 79.7 % of goal nutrition each day in the first 2 weeks. Conclusions: Enteral feeding can be well tolerated by patients who are receiving ECMO, whether in venovenous or venoarterial mode. ECMO should not exclude patients from receiving the well-documented benefits of early enteral feeding in critical illness. [ABSTRACT FROM AUTHOR]

Extracorporeal membrane oxygenation (ECMO) support has a high incidence of both bleeding and thrombotic complications. Despite clear differences in patient characteristics and pathologies between veno-venous (VV) and veno-arterial (VA) ECMO support, anticoagulation practices are often the same across modalities. Moreover, there is very little data on their respective coagulation profiles and comparisons of thrombin generation in these patients. This study compares the coagulation profile and thrombin generation between patients supported with either VV and VA ECMO. A prospective cohort study of patients undergoing VA and VV ECMO at an Intensive care department of a university hospital and ECMO referral centre. In addition to routine coagulation testing and heparin monitoring per unit protocol, thromboelastography (TEG), multiplate aggregometry (MEA), calibrated automated thrombinography (CAT) and von-Willebrand's activity (antigen and activity ratio) were sampled second-daily for 1 week, then weekly thereafter. VA patients had significantly lower platelets counts, fibrinogen, anti-thrombin and clot strength with higher d-dimer levels than VV patients, consistent with a more pronounced consumptive coagulopathy. Thrombin generation was higher in VA than VV patients, and the heparin dose required to suppress thrombin generation was lower in VA patients. There were no significant differences in total bleeding or thrombotic event rates between VV and VA patients when adjusted for days on extracorporeal support. VA patients received a lower median daily heparin dose 8500 IU [IQR 2500–24000] versus VV 28,800 IU [IQR 17,300–40,800.00]; < 0.001. Twenty-eight patients (72%) survived to hospital discharge; comprising 53% of VA patients and 77% of VV patients. Significant differences between the coagulation profiles of VA and VV patients exist, and anticoagulation strategies for patients of these modalities should be different. Further research into the development of tailored anticoagulation strategies that include the mode of ECMO support need to be completed. [ABSTRACT FROM AUTHOR]

A multidisciplinary group of stakeholders were used to identify: (1) the core competencies of a training program required to perform in-hospital ECPR initiation (2) additional competencies required to perform pre-hospital ECPR initiation and; (3) the optimal training method and maintenance protocol for delivering an ECPR program. A modified Delphi process was undertaken utilising two web based survey rounds and one virtual meeting. Experts rated the importance of different aspects of ECPR training, competency and governance on a 9-point Likert scale. A diverse, representative group was targeted. Consensus was achieved when greater than 70% respondents rated a domain as critical (> or = 7 on the 9 point Likert scale). 35 international ECPR experts from 9 countries formed the expert panel, with a median number of 14 years of ECMO practice (interquartile range 11–38). Participant response rates were 97% (survey round one), 63% (virtual meeting) and 100% (survey round two). After the second round of the survey, 47 consensus statements were formed outlining a core set of competencies required for ECPR provision. We identified key elements required to safely train and perform ECPR including skill pre-requisites, surrogate skill identification, the importance of competency-based assessment over volume of practice and competency requirements for successful ECPR practice and skill maintenance. We present a series of core competencies, training requirements and ongoing governance protocols to guide safe ECPR implementation. These findings can be used to develop training syllabus and guide minimum standards for competency as the growth of ECPR practitioners continues. [ABSTRACT FROM AUTHOR]

Objectives: To determine whether randomization of patients undergoing extracorporeal membrane oxygenation to either therapeutic or a low-dose anticoagulation protocol results in a difference in activated partial thromboplastin time and anti-Xa.Design: Randomized, controlled, unblinded study.Setting: Two ICUs of two university hospitals.Patients: Patients admitted to the ICU, who required extracorporeal membrane oxygenation (venovenous or venoarterial) and who did not have a preexisting indication for therapeutic anticoagulation.Interventions: Therapeutic anticoagulation with heparin (target activated partial thromboplastin time between 50 and 70 s) or lower dose heparin (up to 12,000 U/24 hr aiming for activated partial thromboplastin time < 45 s).Measurements and Main Results: Thirty-two patients were randomized into two study groups that were not significantly different in demographics and extracorporeal membrane oxygenation characteristics. There was a significant difference in the daily geometric mean heparin dose (11,742 U [95% CI, 8,601-16,031 U] vs 20,710 U [95% CI, 15,343-27,954 U]; p = 0.004), daily geometric mean activated partial thromboplastin time (48.1 s [95% CI, 43.5-53.2 s] vs 55.5 s [95% CI, 50.4-61.2 s]; p = 0.04), and daily geometric mean anti-Xa (0.11 international units/mL [95% CI, 0.07-0.18] vs 0.27 [95% CI, 0.17-0.42]; p = 0.01). We found similar results when considering only venovenous extracorporeal membrane oxygenation episodes; however, no difference in daily geometric mean activated partial thromboplastin time between groups when considering only venoarterial extracorporeal membrane oxygenation episodes.Conclusions: Allocating patients on extracorporeal membrane oxygenation to two different anticoagulation protocols led to a significant difference in mean daily activated partial thromboplastin time and anti-Xa levels between groups. When considering subgroups analyses, these results were consistent in patients on venovenous extracorporeal membrane oxygenation. Our results support the feasibility of a larger trial in patients undergoing venovenous extracorporeal membrane oxygenation to compare different anticoagulation protocols; however, this study does not provide evidence on the optimal anticoagulation protocol for patients undergoing extracorporeal membrane oxygenation. [ABSTRACT FROM AUTHOR]

Background: The use of extracorporeal membrane oxygenation (ECMO) in refractory cardiac arrest (ECPR) has increased exponentially. ECPR is a resource intensive service and its cost effectiveness has yet to be demonstrated. We sought to complete a cost analysis with modelling of cost effectiveness and quality of life outcomes. We sought to complete a cost analysis with modelling of cost effectiveness and quality of life outcomes of patients who have undergone ECPR.Methods: Using data on all extracorporeal cardiopulmonary resuscitation (ECPR) patients at two ECMO centres in Sydney, Australia; we completed a costing analysis of ECPR patients. A Markov model of cost, quality of life and survival outcomes was developed to examine cost per QALY estimates and incremental cost effectiveness ratios (ICERs). Probabilistic sensitivity analysis (PSA) was completed to assess the probability of cost effectiveness for base case and variations.Results: Sixty-two consecutive ECPR patients were analysed; mean age of 51.9 ± 13.6 years, 38 (61%) were in hospital cardiac arrests (IHCA). Twenty-five patients (40%) survived to hospital discharge; all with a cerebral performance category (CPC) of 1 or 2. The mean cost per ECPR patient was AUD 75,165 (€50,535; ±AUD 75,737). Over 10 years ECPR was estimated to add a mean gain of 3.0 Quality Adjusted Life Years (QALYs) per patient with an incremental cost effectiveness ratio (ICER) of AUD 25,212 (€16,890) per QALY, increasing to 4.0 QALYs and an ICER of AUD 18,829 (€12,614) over a 15-year survival scenario. Mean cost per QALY did not differ significantly by OHCA or IHCA.Conclusions: ECMO support for refractory cardiac arrests is cost effective and compares favourably to accepted cost effectiveness thresholds. [ABSTRACT FROM AUTHOR]

Background: Antegrade cerebral perfusion (ACP) is an essential adjunct for prolonged hypothermic circulatory arrest (HCA) during aortic arch surgery. However, it has yet to be established whether ACP should be delivered unilaterally or bilaterally. The aim of the present meta-analysis is to investigate outcomes of unilateral ACP (uACP) compared to bilateral ACP (bACP) in comparative studies.Methods: Electronic searches were performed using four databases from their inception to February 2017. Relevant comparative studies with adult patients who underwent aortic arch surgery using unilateral or bilateral ACP were included. Data was extracted by two independent researchers and analysed according to predefined endpoints using a random-effects model. Meta-regression was used to identify predictors of primary outcomes.Results: Nine comparative studies were identified, comprising 967 uACP patients and 879 bACP patients. No significant differences in age, sex, or proportion of total arch replacements were identified. The uACP cohort had a greater proportion of acute dissections (86% vs 75%, p = 0.04). Hypothermic circulatory arrest and cerebral perfusion times were similar between both groups. No significant differences were seen between unilateral and bilateral groups in terms of mortality (odds ratio [OR] 0.97; 95% confidence interval [CI] 0.64-1.48; p = 0.90; I2 = 0%), permanent neurological deficit (PND) (OR 1.04; 95% CI 0.74-1.45; p = 0.85; I2 = 0%), temporary neurological deficit (p = 0.74), acute kidney injury (p = 0.36) or reoperation for bleeding (p = 0.65). No factors affecting mortality or PND were identified on meta-regression.Conclusion: For patients undergoing aortic arch surgery, the available evidence supports either uACP or bACP as an adjunct to HCA. However, there is insufficient comparative evidence available to determine the benefit of either modalities in patients with longer durations of circulatory arrest. [ABSTRACT FROM AUTHOR]

Aim To describe the ECPR experience of two Australian ECMO centres, with regards to survival and neurological outcome, their predictors and complications. Methods Retrospective observational study of prospectively collected data on all patients who underwent extracorporeal cardiopulmonary resuscitation (ECPR) at two academic ECMO referral centres in Sydney, Australia. Measurements and main results Thirty-seven patients underwent ECPR, 25 (68%) were for in-hospital cardiac arrests. Median age was 54 (IQR 47–58), 27 (73%) were male. Initial rhythm was ventricular fibrillation or pulseless ventricular tachycardia in 20 patients (54%), pulseless electrical activity ( n = 14, 38%), and asystole ( n = 3, 8%). 27 (73%) arrests were witnessed and 30 (81%) patients received bystander CPR. Median time from arrest to initiation of ECMO flow was 45 min (IQR 30–70), and the median time on ECMO was 3 days (IQR 1–6). Angiography was performed in 54% of patients, and 27% required subsequent coronary intervention (stenting or balloon angioplasty 24%). A total of 13 patients (35%) survived to hospital discharge (IHCA 33% vs. OHCA 37%). All survivors were discharged with favourable neurological outcome (Cerebral Performance Category 1 or 2). Pre-ECMO lactate level was predictive of mortality OR 1.35 (1.06–1.73, p = 0.016). Conclusions In selected patients with refractory cardiac arrest, ECPR may provide temporary support as a bridge to intervention or recovery. We report favourable survival and neurological outcomes in one third of patients and pre-ECMO lactate levels predictive of mortality. Further studies are required to determine optimum selection criteria for ECPR. [ABSTRACT FROM AUTHOR]

Objective: To describe mechanical ventilation settings in adult patients treated for an acute respiratory distress syndrome with extracorporeal membrane oxygenation and assess the potential impact of mechanical ventilation settings on ICU mortality. Design: Retrospective observational study. Setting: Three international high-volume extracorporeal membrane oxygenation centers. Patients: A total of 168 patients treated with extracorporeal membrane oxygenation for severe acute respiratory distress syndrome from January 2007 to January 2013. Interventions: We analyzed the association between mechanical ventilation settings (i.e. plateau pressure, tidal volume, and positive end-expiratory pressure) on ICU mortality using multivariable logistic regression model and Cox-proportional hazards model. Measurement and Main Results: We obtained detailed demographic, clinical, daily mechanical ventilation settings and ICU outcome data. One hundred sixty-eight patients (41 ± 14 years old; Pao2/Fio2 67 ± 19 mm Hg) fulfilled our inclusion criteria. Median duration of extracorporeal membrane oxygenation and ICU stay were 10 days (6–18 d) and 28 days (16–42 d), respectively. Lower positive end-expiratory pressure levels and significantly lower plateau pressures during extracorporeal membrane oxygenation were used in the French center than in both Australian centers (23.9 ± 1.4 vs 27.6 ± 3.7 and 27.8 ± 3.6; p < 0.0001). Overall ICU mortality was 29%. Lower positive end-expiratory pressure levels (until day 7) and lower delivered tidal volume after 3 days on extracorporeal membrane oxygenation were associated with significantly higher mortality (p < 0.05). In multivariate analysis, higher positive end-expiratory pressure levels during the first 3 days of extracorporeal membrane oxygenation support were associated with lower mortality (odds ratio, 0.75; 95% CI, 0.64–0.88; p = 0.0006). Other independent predictors of ICU mortality included time between ICU admission and extracorporeal membrane oxygenation initiation, plateau pressure greater than 30 cm H2O before extracorporeal membrane oxygenation initiation, and lactate level on day 3 of extracorporeal membrane oxygenation support. Conclusions: Protective mechanical ventilation strategies were routinely used in high-volume extracorporeal membrane oxygenation centers. However, higher positive end-expiratory pressure levels during the first 3 days on extracorporeal membrane oxygenation support were independently associated with improved survival. Further prospective trials on the optimal mechanical ventilation strategy during extracorporeal membrane oxygenation support are warranted. [ABSTRACT FROM AUTHOR]

Purpose: To describe the technical challenges, efficacy, complications and maternal and infant outcomes associated with extracorporeal membrane oxygenation (ECMO) for severe adult respiratory distress syndrome (ARDS) in pregnant or postpartum patients during the 2009 H1N1 pandemic. Methods: Twelve critically ill pregnant and postpartum women were included in this retrospective observational study on the application of ECMO for the treatment of severe ARDS refractory to standard treatment. The study was conducted at seven tertiary hospitals in Australia and New Zealand. Results: Of the 12 patients treated with ECMO, 7 (58%) were pregnant and 5 (42%) were postpartum. Their median (interquartile range [IQR]) age was 29 (26-33) years, 6 (50%) were obese. Two patients were initially treated with veno-arterial (VA) ECMO. All others received veno-venous (VV) ECMO with one or two drainage cannulae. ECMO circuit-related complications were rare, circuit change was needed in only two cases and there was no sudden circuit failure. On the other hand, bleeding was common, leading to relatively large volumes of packed red blood cell transfusion (median [IQR] volume transfused was 3,499 [1,451-4,874] ml) and was the main cause of death (three cases). Eight (66%) patients survived to discharge and seven were ambulant, with normal oxygen saturations. The survival rate of infants whose mothers received ECMO was 71% and surviving infants were discharged home with no sequelae. Conclusions: The use of ECMO for severe ARDS in pregnant and postpartum women was associated with a 66% survival rate. The most common cause of death was bleeding. Infants delivered of mothers who had received ECMO had a 71% survival rate and, like their mothers, had no permanent sequelae at hospital discharge. [ABSTRACT FROM AUTHOR]