Respiratory management in severe acute respiratory syndrome coronavirus 2 infection.

The severe acute respiratory syndrome coronavirus 2 pandemic is to date affecting more than a million of patients and is challenging healthcare professionals around the world. Coronavirus disease 2019 may present with a wide range of clinical spectrum and severity, including severe interstitial pneumonia with high prevalence of hypoxic respiratory failure requiring intensive care admission. There has been increasing sharing experience regarding the patient's clinical features over the last weeks which has underlined the need for general guidance on treatment strategies. We summarise the evidence existing in the literature of oxygen and positive pressure treatments in patients at different stages of respiratory failure and over the course of the disease, including environment and ethical issues related to the ongoing coronavirus disease 2019 infection

Frequency of thrombocytopenia and heparin induced thrombocytopenia in patients receiving extracorporeal membrane oxygenation compared to cardiopulmonary bypass and the limited sensitivity of pre-test probability score

Objectives:To ascertain:i)the frequency of thrombocytopeniaand heparininducedthrombocytopenia (HIT), ii)positive predictive value (PPV) of the pre-test probability score (PTPS) in identifying HIT iii)clinical outcome of HITin adult patients receiving veno-venous (VV)-extracorporeal membraneoxygenation(ECMO)or veno-arterial (VA)-ECMO, comparedto cardiopulmonary bypass (CPB). Design: A single-centre, retrospective, observational cohort study from January 2016 to April 2018Setting: Tertiary referral centre for cardiac and respiratory failure Patients:Patients who received ECMOfor>48hrs or had CPB during specified period Interventions: None.Measurements and Main Results:Clinical and laboratory data were collected retrospectively. PTPS and HIT testing results were collected prospectively. Mean age (standard deviation) of the EMCO and CPB cohorts were 45.4 (±15.6) and 64.9 (±13), p< 0.00001.Median duration of CPB was 4.6 [2-16.5]hrs compared to 170.4[70-1008] hrson ECMO.Moderateand severethrombocytopenia were more common in ECMO compared to CPB throughout (p<0.0001).Thrombocytopenia increased in CPB patients on day2 but was 4normal in 83% compared to 42.3 % ofECMOpatients at day 10. Patients on ECMO also followed a similar pattern of platelet recoveryfollowing cessation of ECMO. The incidences of HIT in ECMO and CPB were 6.4% (19/298) and 0.6% (18/2998) respectivelyp<0.0001). There was no difference in prevalence of HIT in patients on VV-ECMO (9/156, 5.7%) vs VA-ECMO (11/142, 7.7%), p=0.81. The PPV of the PTPS in identifying HIT in patients post-CPB and on ECMO were 56.25% (18/32) and 25% (15/60) respectively. Mortalitywas not different with (6/19, 31.6%) or without (89/279, 32.2%) HIT in patients on ECMO,p=0.79. Conclusions Thrombocytopenia is already common at ECMO initiation. HIT is more frequent in both VV-and VA-ECMO compared to CPB. PPV of PTPSin identifying HIT was lower inECMO patients.HIT had no effect on mortality

Thrombosis, major bleeding, and survival in COVID-19 supported by VV- ECMO in the first vs second wave- multicentre observational study in the UK

BACKGROUND: Bleeding and thrombosis are major complications of veno-venous extracorporeal membrane (VV-ECMO). OBJECTIVES: To assess thrombosis, major bleeding (MB) and 180-day in patients supported by VV-ECMO between first (1st March-31st May 2020) and second (1st June 2020-30th June 2021) waves of the COVID-19 pandemic. PATIENTS/METHODS: Observational study of 309 consecutive patients (≥18years) with severe COVID-19 supported by VV-ECMO in four nationally commissioned ECMO centres, UK. RESULTS: Median age was 48 (19-75)years and 70.6% were male. Probabilities of survival, thrombosis, and MB at 180 days in the overall cohort were 62.5% (193/309), 39.8%(123/309) and 30%(93/309). In multivariate analysis, age >55 years (HR 2.29 [1.33-3.93],p=0.003) and elevated creatinine (HR 1.91 [1.19-3.08],p=0.008) were associated with increased mortality. Corrected for duration of VV-ECMO support, arterial thrombosis alone (HR 3.0 [95% CI1.5-5.9], P= 0.002) or circuit thrombosis alone (HR 3.9 [95% 2.4-6.3], P<0.001), but not venous thrombosis, increased mortality. MB during ECMO had 3-fold risk (95% CI 2.6-5.8, P<0.001) of mortality. The first wave cohort had more males (76.7% vs 64%, p=0.014), higher 180-day survival (71.1% vs 53.3% p=0.003), more venous thrombosis alone (46.4% vs 29.2%, p=0.02) and lower circuit thrombosis (9.2% vs 28.1%, p<0.001). The second wave cohort received more steroids (121/150 [80.6%] vs 86/159 [54.1%], p<0.0001) and Tocilizumab (20/150 [13.3%] vs 4/159 [2.5%] p=0.005). CONCLUSIONS: MB and thrombosis are frequent complications in patients on VV-ECMO and significantly increase mortality. Arterial thrombosis alone or circuit thrombosis alone increased mortality whilst venous thrombosis alone had no effect. MB during ECMO support increased mortality 3.9-fold

Thombosis, major bleeding, and survival in COVID-19 supported by veno-venous extracorporeal membrane oxygenation in the first vs second wave: a multicenter observational study in the United Kingdom

Background Bleeding and thrombosis are major complications of veno-venous (VV) extracorporeal membrane oxygenation (ECMO). Objectives To assess thrombosis, major bleeding (MB), and 180-day survival in patients supported by VV-ECMO between the first (March 1 to May 31, 2020) and second (June 1, 2020, to June 30, 2021) waves of the COVID-19 pandemic. Methods An observational study of 309 consecutive patients (aged ≥18years) with severe COVID-19 supported by VV-ECMO was performed in 4 nationally commissioned ECMO centers in the United Kingdom. Results Median age was 48 (19-75) years, and 70.6% were male. Probabilities of survival, thrombosis, and MB at 180 days in the overall cohort were 62.5% (193/309), 39.8% (123/309), and 30% (93/309), respectively. In multivariate analysis, an age of >55 years (hazard ratio [HR], 2.29; 95% CI, 1.33-3.93; P = .003) and an elevated creatinine level (HR, 1.91; 95% CI, 1.19-3.08; P = .008) were associated with increased mortality. Correction for duration of VV-ECMO support, arterial thrombosis alone (HR, 3.0; 95% CI, 1.5-5.9; P = .002) or circuit thrombosis alone (HR, 3.9; 95% CI, 2.4-6.3; P < .001) but not venous thrombosis increased mortality. MB during ECMO had a 3-fold risk (95% CI, 2.6-5.8, P < .001) of mortality. The first wave cohort had more males (76.7% vs 64%; P = .014), higher 180-day survival (71.1% vs 53.3%; P = .003), more venous thrombosis alone (46.4% vs 29.2%; P = .02), and lower circuit thrombosis (9.2% vs 28.1%; P < .001). The second wave cohort received more steroids (121/150 [80.6%] vs 86/159 [54.1%]; P < .0001) and tocilizumab (20/150 [13.3%] vs 4/159 [2.5%]; P = .005). Conclusion MB and thrombosis are frequent complications in patients on VV-ECMO and significantly increase mortality. Arterial thrombosis alone or circuit thrombosis alone increased mortality, while venous thrombosis alone had no effect. MB during ECMO support increased mortality by 3.9-fold. Keywords: COVID-19; extracorporeal membrane oxygenation; hemorrhage; mortality; thrombosi

The ATHENA X-ray Integral Field Unit (X-IFU)

The X-ray Integral Field Unit (X-IFU) is the high resolution X-ray spectrometer of the ESA Athena X-ray observatory. Over a field of view of 5' equivalent diameter, it will deliver X-ray spectra from 0.2 to 12 keV with a spectral resolution of 2.5 eV up to 7 keV on ∼ 5" pixels. The X-IFU is based on a large format array of super-conducting molybdenum-gold Transition Edge Sensors cooled at ∼ 90 mK, each coupled with an absorber made of gold and bismuth with a pitch of 249 μm. A cryogenic anti-coincidence detector located underneath the prime TES array enables the non X-ray background to be reduced. A bath temperature of ∼ 50 mK is obtained by a series of mechanical coolers combining 15K Pulse Tubes, 4K and 2K Joule-Thomson coolers which pre-cool a sub Kelvin cooler made of a 3He sorption cooler coupled with an Adiabatic Demagnetization Refrigerator. Frequency domain multiplexing enables to read out 40 pixels in one single channel. A photon interacting with an absorber leads to a current pulse, amplified by the readout electronics and whose shape is reconstructed on board to recover its energy with high accuracy. The defocusing capability offered by the Athena movable mirror assembly enables the X-IFU to observe the brightest X-ray sources of the sky (up to Crab-like intensities) by spreading the telescope point spread function over hundreds of pixels. Thus the X-IFU delivers low pile-up, high throughput (< 50%), and typically 10 eV spectral resolution at 1 Crab intensities, i.e. A factor of 10 or more better than Silicon based X-ray detectors. In this paper, the current X-IFU baseline is presented, together with an assessment of its anticipated performance in terms of spectral resolution, background, and count rate capability. The X-IFU baseline configuration will be subject to a preliminary requirement review that is scheduled at the end of 2018

Leptospirosis as an important differential of pulmonary haemorrhage on the intensive care unit: a case managed with VV-ECMO

Background Leptospirosis is a potentially fatal zoonosis. It can cause a wide range of symptoms, including diffuse alveolar haemorrhage which occurs in a minority of cases but carries a mortality of over 70%. These patients may present with severe acute respiratory failure. The differential diagnosis for diffuse alveolar haemorrhage is broad whereas prompt diagnosis and treatment can be lifesaving. Case presentation A 20-year-old previously fit and well trout farm worker presented with a 3-day history of malaise, fevers, diarrhoea, vomiting and jaundice. He developed haemoptysis, severe headaches, neck stiffness and photophobia on the day of emergency admission. He was anaemic and thrombocytopenic. Anuric acute kidney injury (urea 32, creat 507) required immediate haemofiltration. In view of progressive respiratory failure with four-quadrant lung infiltrates on imaging, he was given broad spectrum antibiotics and pulsed methylprednisolone empirically, in case of a vasculitic pulmonary-renal presentation. He was intubated within 48 h of admission. Despite attempted protective ventilatory management, he remained hypoxaemic and developed pneumomediastinum. He was retrieved to a specialist cardiorespiratory intensive care unit on femoro-femoral mobile VV-ECMO. Three days from admission, results showed positive Leptospira IgM and real-time PCR. Serial bronchoscopies showed old and fresh clots, but not the classical progressive late red tinge of the returned lavage fluid. After eight days, VV-ECMO was weaned, he was extubated three days later, and made a full recovery. At 9 months follow-up, he was clinically better, with resolution of the CT scan findings and near normal lung function, albeit with low normal gas transfer. Conclusions Leptospirosis is a rare but important differential to be considered in diffuse alveolar haemorrhage presenting to the ICU, especially in young males. A thorough history for occupational or recreational risk factors may offer the diagnostic clue. Most patients recover fully with antibiotics. However, resulting acute severe respiratory failure can ensue. In this situation, early consideration for respiratory ECMO support offers time for clearance of endobronchial clot, parenchymal recovery, and prevention of ventilator-induced lung injury. Steroids have no clear evidence but may be used to avoid delay in treating suspected vasculitic or autoimmune causes of diffuse alveolar haemorrhage

296: Determinants of ARDS resolution and duration in patients supported with extracorporeal support

Introduction: Extracorporeal membrane oxygenation (ECMO) is used to provide life-sustaining support to patients with severe acute respiratory distress syndrome (ARDS). Its use has dramatically increased during the current COVID-19 pandemic. Delayed resolution is associated with poorer patient outcomes and current prediction scores focus on mortality. This study aimed to identify pre-ECMO clinical characteristics that determine early ARDS resolution, to assist clinicians in planning appropriate treatment. Methods: In this retrospective observational study, point of referral data from patients treated with veno-venous ECMO at a regional centre (2017-2019) were analysed. Patients aged 18 years and above with ARDS, defined by the Berlin criteria, were included. The primary outcome was early ARDS resolution, defined as liberation from ECMO within 14 days, or non-early ARDS resolution, defined as ECMO run longer than 14 days (survivors and non-survivors). Multiple logistic and backwards step-wise logistic regression were used to identify independent predictors. Multiple imputation was used for missing values. Results: Of the 159 patients included in the study, 86 (54.1%) had early ARDS resolution. Following univariate analysis and exclusion of colinear variables, multiple logistic regression showed aspiration pneumonia to be a significant predictor of early resolution. Plateau pressure, social alcohol use and prophylactic heparin were significant predictors of non-early resolution. Backwards step-wise regression retained plateau pressure (odds ratio [OR] 1.15, 95% confidence interval [CI] 1.06-1.24, p=0.001), social alcohol use (OR 2.73, 95% CI 1.17-6.34, p=0.020), prophylactic heparin (OR 3.24, 95% CI 1.46-7.21, p=0.004), aspiration pneumonia (OR 0.19, 95% CI 0.06-0.62, p=0.006) and log (FiO2) (OR 0.06, 95% CI 0.005-0.64, p=0.02) as independent significant predictors. Conclusions: This study identified important clinical characteristics at the point of referral, in particular the aetiology of ARDS, that predict disease dynamics in ARDS patients receiving ECMO. These can help better prepare families, inform clinicians, plan resource utilization and guide future research into severe ARDS

Survival benefit of extracorporeal membrane oxygenation in severe COVID-19: a multi-centre matched cohort study

Purpose Extracorporeal membrane oxygenation (ECMO) has become an established therapy for severe respiratory failure in coronavirus disease 2019 (COVID-19). The added benefit of receiving ECMO in COVID-19 remains uncertain. The aim of this study is to analyse the impact of receiving ECMO at specialist centres on hospital mortality. Methods A multi-centre retrospective study was conducted in COVID-19 patients from 111 hospitals, referred to two specialist ECMO centres in the United Kingdom (UK) (March 2020 to February 2021). Detailed covariate data were contemporaneously curated from electronic referral systems. We analysed added benefit of ECMO treatment in specialist centres using propensity score matching techniques. Results 1363 patients, 243 receiving ECMO, were analysed. The best matching technique generated 209 matches, with a marginal odds ratio (OR) for mortality of 0.44 (95% CI 0.29–0.68, p < 0.001) and absolute mortality reduction of 18.2% (44% vs 25.8%, p < 0.001) for treatment with ECMO in a specialist centre. Conclusion We found ECMO provided at specialist centres conferred significant survival benefit. Where resources and specialism allow, ECMO should be widely offered