BACKGROUND AND AIMS:Guidelines suggest non-traumatic out-of-hospital cardiac arrest (OHCA) be conveyed to cardiac arrest centres (CAC). We hypothesised that (a) a pre-hospital conveyance algorithm based on initial presenting rhythm following OHCA is feasible and (b) that would demonstrate survival advantage. METHODS:This observational pilot study included all consecutive patients with OHCA from suspected cardiac aetiology from the county of Essex, United Kingdom from April 2022-April 2023. For the first 6 months, OHCA patients had conveyance as standard of care. For the next 6 months, consecutive OHCA patients with STEMI or initial shockable rhythm were directly conveyed to the CAC, initial non-shockable rhythm without STEMI continued to be taken to the nearest Emergency Department (BCIS protocol). Primary outcome was death from any cause at 30 days. Secondary outcome was survival with favourable neurological outcome. RESULTS:Of 330 patients (mean age 67.5 ± 13.1, 66% male), 162 patients were in the standard care group and 168 in the BCIS conveyance group. Algorithm implementation was associated with numerically lower all cause 30-day mortality [(81% vs 73%, RR 1.10 (95% CI 0.98-1.24) p = 0.10] and numerically higher 30-day survival with favourable neurological outcome [15% vs 19%, RR 1.05 (0.95-1.15), p = 0.38]. Post hoc analysis showed that the BCIS conveyance algorithm was associated with lower 30 day mortality in those with an initial shockable rhythm [(61% vs 41%, RR 1.5 (95% CI 1.05-2.13) p = 0.02 and in those with a MIRACLE2 score ≤ 5 [(63%% vs 38%, RR 0.59 (95% CI 0.61-0.86) p = 0.005]. CONCLUSIONS:The BCIS algorithm is feasible and did not impact overall mortality, but there is signal that direct conveyance of OHCA patients with an initial shockable rhythm and low MIRACLE2 score, to a dedicated CAC may improve survival.

IMPORTANCE AND OBJECTIVES:Inhaled volatile anesthetics are employed as rescue therapy in near-fatal asthma, despite limited evidence. This study aims to describe the characteristics, management, and outcomes of mechanically ventilated adult patients with near-fatal asthma, stratified by the use of volatile anesthetic therapy. DESIGN:Retrospective single-center observational cohort study. SETTING:Tertiary critical care and extracorporeal membrane oxygenation (ECMO) unit. PARTICIPANTS:Adults 16 years old or older receiving mechanical ventilation (MV) for greater than or equal to 24 hours and/or ECMO between January 2016 and August 2023 for near-fatal asthma. MAIN OUTCOMES AND MEASURES:We recorded demographics, disease severity tidal volumes, and ventilator settings, by treatment over the first 100 hours. Outcomes were duration of ECMO and MV, ICU length of stay, 90-day mortality, and adverse drug reaction. RESULTS:Sixty-two patients were included (62.9% female), with a median (interquartile range [IQR]) age of 45 years (29-51 yr). Median (IQR) pH 7.13 (6.93-7.23), Paco2 12.9 kPa (8.7-16.2 kPa), and tidal volume 178 mL (50-300 mL). Most patients received IV bronchodilators and 32 (51.6%) required ECMO. Thirty-eight patients (61.3%) were treated with volatile anesthetics. Volatile patients had worse ventilation and blood gas parameters before treatment, more barotrauma, and were more likely to be receiving ECMO. Despite this, improvements in tidal volume occurred in the volatile group (mean increase, 204 mL [83.9%]; 95% CI, 110-298; p < 0.001). Median (IQR) duration of MV and ICU length of stay in volatile and no volatile patients were 10 days (8-16 d) vs. 5 days (3-10 d; p = 0.001) and 15 days (13-20 d) vs. 9 days (7-14 d; p = 0.001), respectively. ICU and 90-day mortality in volatile and no volatile patients were 5.3% vs. 4.2%. CONCLUSIONS AND RELEVANCE:The use of inhaled volatile anesthetics for near-fatal asthma, including during ECMO, appears to be feasible and safe, and with favorable clinical outcomes; however, no conclusions regarding efficacy can be directly inferred.

Background Awake prone positioning (APP) may be beneficial in patients with respiratory failure who are not receiving mechanical ventilation. Randomized controlled trials of APP have been performed during peak COVID-19 periods in unvaccinated populations, with limited data on compliance or patient acceptability. We aimed to evaluate the efficacy and acceptability of APP in a lower-middle income country in an open-label randomized controlled trial using a dedicated APP implementation team and wearable continuous-monitoring devices. Methods The trial was performed at a tertiary level hospital in Ho Chi Minh City, Vietnam, recruiting adults (≥18 years) hospitalized with moderate or severe COVID-19 and receiving supplemental oxygen therapy via nasal/facemask systems or high-flow nasal cannula (HFNC). Patients were allocated by a computer-generated random number sequence in a 1:1 ratio to standard care or APP, where a dedicated team provided bedside support. Wearable devices continuously recorded pulse oximetry and body position continuously. Our primary outcome was escalation of respiratory support within 28 days of randomization. Results Ninety-three patients were enrolled in this study between March 2022 and March 2023. Eighty (86%) patients had received ≥2 doses of SARS-CoV2 vaccine. The study was terminated early because of a reduction in the number of eligible patients. Data from 46 patients allocated to APP and 47 to standard care were available for analysis. At baseline, 19/47 (40%) patients allocated to the standard care group and 14/46 (30%) patients allocated to the APP group received HFNC. Continuous monitoring data were available for all patients monitored with wearable devices. Significantly greater mean daily APP times were achieved in those allocated to APP, however, most achieved less than the target 8 h/day. We did not detect clear differences in the primary outcome (relative risk,RR, 0.85, 95% CI 0.40-1.78, p=0.67) or secondary outcomes, including intubation rate and 28-day mortality. Patients reported prone positioning was comfortable, although almost all patients preferred supine positioning. No adverse events associated with the intervention were observed. Conclusions APP was not associated with benefit, but there was no sign of harm. Continuous monitoring with wearable devices is both feasible and acceptable for patients. In our population, achieving prolonged APP time was challenging despite a dedicated support team, and patients preferred supine positioning. Clinical Trials Registration NCT05083130.

Background Awake prone positioning (APP) may be beneficial in patients with respiratory failure who are not receiving mechanical ventilation. Randomized controlled trials of APP have been performed during peak COVID-19 periods in unvaccinated populations, with limited data on compliance or patient acceptability. We aimed to evaluate the efficacy and acceptability of APP in a lower-middle income country in an open-label randomized controlled trial using a dedicated APP implementation team and wearable continuous-monitoring devices. Methods The trial was performed at a tertiary level hospital in Ho Chi Minh City, Vietnam, recruiting adults (≥18 years) hospitalized with moderate or severe COVID-19 and receiving supplemental oxygen therapy via nasal/facemask systems or high-flow nasal cannula (HFNC). Patients were allocated by a computer-generated random number sequence in a 1:1 ratio to standard care or APP, where a dedicated team provided bedside support. Wearable devices continuously recorded pulse oximetry and body position continuously. Our primary outcome was escalation of respiratory support within 28 days of randomization. Results Ninety-three patients were enrolled in this study between March 2022 and March 2023. Eighty (86%) patients had received ≥2 doses of SARS-CoV2 vaccine. The study was terminated early because of a reduction in the number of eligible patients. Data from 46 patients allocated to APP and 47 to standard care were available for analysis. At baseline, 19/47 (40%) patients allocated to the standard care group and 14/46 (30%) patients allocated to the APP group received HFNC. Continuous monitoring data were available for all patients monitored with wearable devices. Significantly greater mean daily APP times were achieved in those allocated to APP, however, most achieved less than the target 8 h/day. We did not detect clear differences in the primary outcome (relative risk,RR, 0.85, 95% CI 0.40-1.78, p=0.67) or secondary outcomes, including intubation rate and 28-day mortality. Patients reported prone positioning was comfortable, although almost all patients preferred supine positioning. No adverse events associated with the intervention were observed. Conclusions APP was not associated with benefit, but there was no sign of harm. Continuous monitoring with wearable devices is both feasible and acceptable for patients. In our population, achieving prolonged APP time was challenging despite a dedicated support team, and patients preferred supine positioning. Clinical Trials Registration NCT05083130.

Anaesthesia ReportsVolume 12, Issue 1 e12285 Clinical Report A novel association of Legionella pneumophila-induced haemophagocytic lymphohistiocytosis and the 'atoll' sign A. Sotiriou, Corresponding Author A. Sotiriou Specialty Registrar [email protected] orcid.org/0000-0001-5037-2206 hasyourregtried Department of Anaesthesia, Guy's and St Thomas' NHS Foundation Trust, London, UK Correspondence to: A. Sotiriou Email: [email protected]Search for more papers by this authorN. Sivarasan, N. Sivarasan Consultant Department of Radiology, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this authorG. Glover, G. Glover Consultant Department of Anaesthesia, Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this authorR. Lewis, R. Lewis Consultant Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this authorS. Agarwal, S. Agarwal Consultant Department of Rheumatology, Guy's and St Thomas' NHS Foundation Trust, London, UK Lung Inflammation Team, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this authorB. Lams, B. Lams Consultant Lung Inflammation Team, Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Respiratory Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this author A. Sotiriou, Corresponding Author A. Sotiriou Specialty Registrar [email protected] orcid.org/0000-0001-5037-2206 hasyourregtried Department of Anaesthesia, Guy's and St Thomas' NHS Foundation Trust, London, UK Correspondence to: A. Sotiriou Email: [email protected]Search for more papers by this authorN. Sivarasan, N. Sivarasan Consultant Department of Radiology, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this authorG. Glover, G. Glover Consultant Department of Anaesthesia, Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this authorR. Lewis, R. Lewis Consultant Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this authorS. Agarwal, S. Agarwal Consultant Department of Rheumatology, Guy's and St Thomas' NHS Foundation Trust, London, UK Lung Inflammation Team, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this authorB. Lams, B. Lams Consultant Lung Inflammation Team, Guy's and St Thomas' NHS Foundation Trust, London, UK Department of Respiratory Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UKSearch for more papers by this author First published: 06 March 2024 https://doi.org/10.1002/anr3.12285 1 Specialty Registrar, 3 Consultant, Department of Anaesthesia, 2 Consultant, Department of Radiology, 4 Consultant, Department of Intensive Care Medicine, 5 Consultant, Department of Rheumatology, 7 Consultant, Department of Respiratory Medicine, 6 Consultant, Lung Inflammation Team, Guy's and St Thomas' NHS Foundation Trust, London, UK Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat No abstract is available for this article. References 1Thomas W, Veer MV, Besser M. Haemophagocytic lymphohistiocytosis: an elusive syndrome. Clinical Medicine Journal (London) 2016; 16: 432–436. 10.7861/clinmedicine.16-5-432 PubMedWeb of Science®Google Scholar 2Rouphael NG, Talati NJ, Vaughan C, Cunningham K, Moreira R, Gould C. Infections associated with haemophagocytic syndrome. Lancet Infectious Diseases 2007; 7: 814–822. 10.1016/S1473-3099(07)70290-6 CASPubMedWeb of Science®Google Scholar 3Fardet L, Galicier L, Lambotte O, et al. Development and validation of H score, a score for the diagnosis of reactive hemophagocytic syndrome. Arthritis and Rheumatology 2014; 66: 2613–2620. 10.1002/art.38690 PubMedWeb of Science®Google Scholar 4Henter JI, Horne A, Arico M, et al. HLH-2004: diagnostic and therapeutic guidelines for haemophagocytic lymphohistiocytosis. Pediatric Blood and Cancer 2007; 48: 124–131. 10.1002/pbc.21039 PubMedWeb of Science®Google Scholar 5Zompatori M, Poletti V, Battista G, Diegoli M. Bronchiolitis obliterans with organizing pneumonia (BOOP), presenting as a ring-shaped opacity at HRCT (the atoll sign). A case report. La Radiologica Medica 1999; 97: 308–310. CASPubMedGoogle Scholar Volume12, Issue1January‐June 2024e12285 ReferencesRelatedInformation

Background Awake prone positioning (APP) may be beneficial in patients with respiratory failure who are not receiving mechanical ventilation. Randomized controlled trials of APP have been performed during peak COVID-19 periods in unvaccinated populations, with limited data on compliance or patient acceptability. We aimed to evaluate the efficacy and acceptability of APP in a lower-middle income country in an open-label randomized controlled trial using a dedicated APP implementation team and wearable continuous-monitoring devices. Methods The trial was performed at a tertiary level hospital in Ho Chi Minh City, Vietnam, recruiting adults (≥18 years) hospitalized with moderate or severe COVID-19 and receiving supplemental oxygen therapy via nasal/facemask systems or high-flow nasal cannula (HFNC). Patients were allocated by a computer-generated random number sequence in a 1:1 ratio to standard care or APP, where a dedicated team provided bedside support. Wearable devices continuously recorded pulse oximetry and body position continuously. Our primary outcome was escalation of respiratory support within 28 days of randomization. Results Ninety-three patients were enrolled in this study between March 2022 and March 2023. Eighty (86%) patients had received ≥2 doses of SARS-CoV2 vaccine. The study was terminated early because of a reduction in the number of eligible patients. Data from 46 patients allocated to APP and 47 to standard care were available for analysis. At baseline, 19/47 (40%) patients allocated to the standard care group and 14/46 (30%) patients allocated to the APP group received HFNC. Continuous monitoring data were available for all patients monitored with wearable devices. Significantly greater mean daily APP times were achieved in those allocated to APP, however, most achieved less than the target 8 h/day. We did not detect clear differences in the primary outcome (relative risk,RR, 0.85, 95% CI 0.40-1.78, p=0.67) or secondary outcomes, including intubation rate and 28-day mortality. Patients reported prone positioning was comfortable, although almost all patients preferred supine positioning. No adverse events associated with the intervention were observed. Conclusions APP was not associated with benefit, but there was no sign of harm. Continuous monitoring with wearable devices is both feasible and acceptable for patients. In our population, achieving prolonged APP time was challenging despite a dedicated support team, and patients preferred supine positioning. Clinical Trials Registration NCT05083130.

Critical illness is a continuum with different phases and trajectories. The "Intensive Care Unit (ICU) without walls" concept refers to a model whereby care is adjusted in response to the patient's needs, priorities, and preferences at each stage from detection, escalation, early decision making, treatment and organ support, followed by recovery and rehabilitation, within which all healthcare staff, and the patient are equal partners. The rapid response system incorporates monitoring and alerting tools, a multidisciplinary critical care outreach team and care bundles, supported with education and training, analytical and governance functions, which combine to optimise outcomes of critically ill patients, independent of location.

The optimal strategy to manage hypoxaemic respiratory failure associated with COVID-19 remains uncertain. Potentially overwhelming demand on critical care resources requires strategies to reduce progression to invasive ventilation. Awake prone positioning has been proposed, 1 with evidence that it is associated with improved oxygenation in selected patients. 2–5 The aim of this study is to report our experience using APP and its impact on respiratory physiology in COVID-19.

Evidence mainly from high income countries suggests that lying in the prone position may be beneficial in patients with COVID-19 even if they are not receiving invasive ventilation. Studies indicate that increased duration of prone position may be associated with improved outcomes, but achieving this requires additional staff time and resources. Our study aims to support prolonged (≥ 8hours/day) awake prone positioning in patients with moderate to severe COVID-19 disease in Vietnam. We use a specialist team to support prone positioning of patients and wearable devices to assist monitoring vital signs and prone position and an electronic data registry to capture routine clinical data.

Out-of-hospital cardiac arrest (OHCA) affects 80,000 patients per year in the UK; despite improvements in care, survival to discharge remains lower than 10%. NHS England and several societies recommend all resuscitated OHCA patients be directly transferred to a cardiac arrest centre (CAC). However, evidence is limited that all patients benefit from transfer to a CAC, and there are significant organisational, logistic and financial implications associated with such change in policies. Furthermore, there is significant variability in interventional cardiovascular practices for OHCA. Accordingly, the British Cardiovascular Interventional Society established a multidisciplinary group to address variability in practice and provide recommendations for the development of cardiac networks. In this position statement, we recommend: the formal establishment of dedicated CACs; a pathway of conveyance to CACs; and interventional practice to standardise our approach. Further research is needed to understand the role of CACs and which interventions benefit patients with OHCA to support wide-scale changes in networks of care across the UK.

BACKGROUND:During the COVID-19 pandemic, portable pulse oximeters were issued to some patients to permit home monitoring and alleviate pressure on inpatient wards. Concerns were raised about the accuracy of these devices in some patient groups. This study was conducted in response to these concerns.OBJECTIVES:To evaluate the performance characteristics of five portable pulse oximeters and their suitability for deployment on home-use pulse oximetry pathways created during the COVID-19 pandemic. This study considered the effects of different device models and patient characteristics on pulse oximeter accuracy, false negative and false positive rate.METHODS:A total of 915 oxygen saturation (spO2) measurements, paired with measurements from a hospital-standard pulse oximeter, were taken from 50 patients recruited from respiratory wards and the intensive care unit at an acute hospital in London. The effects of device model and several patient characteristics on bias, false negative and false positive likelihood were evaluated using multiple regression analyses.RESULTS AND CONCLUSIONS:All five portable pulse oximeters appeared to outperform the standard to which they were manufactured. Device model, patient spO2 and patient skin colour were significant predictors of measurement bias, false positive and false negative rate, with some variation between models. The false positive and false negative rates were 11.2% and 24.5%, respectively, with substantial variation between models.

OBJECTIVES:The National Early Warning Score 2 (NEWS2) is validated for predicting acute deterioration, however, the binary grading of inspired oxygen fraction (FiO2) may limit performance. We evaluated the incorporation of FiO2 as a weighted categorical variable on NEWS2 prediction of patient deterioration.SETTING:Two hospitals at a single medical centre, Guy's and St Thomas' NHS Foundation Trust.DESIGN:Retrospective cohort of all ward admissions, with a viral respiratory infection (SARS-CoV-2/influenza).PARTICIPANTS:3704 adult ward admissions were analysed between 01 January 2017 and 31 December 2021.METHODS:The NEWS-FiO2 score transformed FiO2 into a weighted categorical variable, from 0 to 3 points, substituting the original 0/2 points. The primary outcome was a composite of cardiac arrest, unplanned critical care admission or death within 24 hours of the observation. Sensitivity, positive predictive value (PPV), number needed to evaluate (NNE) and area under the receiver operating characteristic curve (AUROC) were calculated. Failure analysis for the time from trigger to outcome was compared by log-rank test.RESULTS:The mean age was 60.4±19.4 years, 52.6% were men, with a median Charlson Comorbidity of 0 (IQR 3). The primary outcome occurred in 493 (13.3%) patients, and the weighted FiO2 score was strongly associated with the outcome (p=<0.001). In patients receiving supplemental oxygen, 78.5% of scores were reclassified correctly and the AUROC was 0.81 (95% CI 0.81 to 0.81) for NEWS-FiO2 versus 0.77 (95% CI 0.77 to 0.77) for NEWS2. This improvement persisted in the whole cohort with a significantly higher failure rate for NEWS-FiO2 (p=<0.001). At the 5-point threshold, the PPV increased by 22.0% (NNE 6.7) for only a 3.9% decrease in sensitivity.CONCLUSION:Transforming FiO2 into a weighted categorical variable improved NEWS2 prediction for patient deterioration, significantly improving the PPV. Prospective external validation is required before institutional implementation.

OBJECTIVE:Encephalopathy is a major neurological complication of severe Coronavirus Disease 2019 (COVID-19), but has not been fully defined yet. Further, it remains unclear whether neurological manifestations are primarily due to neurotropism of the virus, or indirect effects, like cerebral hypoxia.METHODS:We analysed the electroencephalograms (EEGs) of 19 consecutive patients with laboratory-confirmed COVID-19, performed at peak disease severity as part of their clinical management. Disease severity, respiratory failure, immune and metabolic dysfunction, sedation status, and neurological examination on the day of the EEG were noted.RESULTS:Severe encephalopathy was confirmed in 13 patients, all with severe COVID-19; 10 remained comatose off sedation, and five of them had alpha coma (AC). Disease severity, sedation, immune and metabolic dysfunction were not different between those with AC and those without.CONCLUSIONS:Severe COVID-19 encephalopathy is a principal cause of persisting coma after sedation withdrawal. The relatively high incidence of the rare AC pattern may reflect direct SARS-CoV-2 neurotropism with a predilection for the brainstem ascending reticular system.SIGNIFICANCE:Systematic early EEG detection of encephalopathy related to severe COVID-19 is important for the acute care and the management of long-term neurological and cognitive sequelae, and may help our better understanding of its pathophysiology.

Objectives: Changes in right ventricular size and function are frequently observed in patients with severe acute respiratory distress syndrome. The majority of patients who receive venovenous extracorporeal membrane oxygenation undergo chest CT and transthoracic echocardiography. The aims of this study were to compare the use of CT and transthoracic echocardiography to evaluate the right ventricular function and to determine the prevalence of acute cor pulmonale in this patient population. Design: Observational, retrospective, single-center, cohort study. Setting: Severe respiratory failure and extracorporeal membrane oxygenation center. Patients: About 107 patients with severe acute respiratory distress syndrome managed with venovenous extracorporeal membrane oxygenation. Interventions: Chest CT to evaluate right ventricular size and transthoracic echocardiography to evaluate right ventricular size and function. Measurements and Main Results: All 107 patients had a qualitative assessment of right ventricular size and function on transthoracic echocardiography. Quantitative measurements were available in 54 patients (50%) who underwent transthoracic echocardiography and in 107 of patients (100%) who received CT. Right ventricular dilatation was defined as a right ventricle end-diastolic diameter greater than left ventricular end-diastolic diameter upon visual assessment or an right ventricle end-diastolic diameter/left ventricular end-diastolic diameter and/or right ventricle cavity area/left ventricular cavity area of greater than 0.9. Right ventricle systolic function was visually estimated as being normal or impaired (visual right ventricular systolic impairment). The right ventricle was found to be dilated in 38/107 patients (36%) and in 58/107 patients (54%), using transthoracic echocardiography or CT right ventricle end-diastolic diameter/left ventricular end-diastolic diameter, respectively. When the CT right ventricle cavity/left ventricular cavity area criterion was used, the right ventricle was dilated in 19/107 patients (18%). About 33/107 patients (31%) exhibited visual right ventricular systolic impairment. Transthoracic echocardiography right ventricle end-diastolic diameter/left ventricular end-diastolic diameter showed good agreement with CT right ventricle cavity/left ventricular cavity area (R 2 = 0.57; p < 0.01). A CT right ventricle cavity/left ventricular cavity area greater than 0.9 provided the optimal cutoff for acute cor pulmonale on transthoracic echocardiography with an AUC of 0.78. Acute cor pulmonale was defined by the presence of a right ventricle “D-shape” and quantitative right ventricle dilatation on transthoracic echocardiography or a right ventricle cavity/left ventricular cavity area greater than 0.9 on CT. A diagnosis of acute cor pulmonale was made in 9/54 (14% patients) on transthoracic echocardiography and in 19/107 (18%) on CT. Conclusions: Changes in right ventricular size and function are common in patients with severe acute respiratory distress syndrome requiring venovenous extracorporeal membrane oxygenation with up to 18% showing imaging evidence of acute cor pulmonale. A CT right ventricular cavity /left ventricular cavity area greater than 0.9 is indicative of impaired right ventricular systolic function.

Targeted temperature management (TTM) is recommended after out-of-hospital cardiac arrest (OHCA). However, interpretation of the evidence and translation into clinical practice, to realize benefits to patient outcomes may be inconsistent. This study aims to compare compliance with the recommended targeted temperatures and the use of intravascular temperature management (IVTM), as well as 90-day survival, before and after publication of the TTM trial. A single-center retrospective cohort study was conducted from 2010 to 2017. All comatose patients admitted to the intensive care unit after OHCA, who survived for ≥24 hours, were included. IVTM use was measured and TTM adherence was defined as the percentage time the core temperature was (1) within the guideline-recommended temperature range (initially 32-34°C, later modified to 32-36°C) for the first 24 hours, and (2) ≤37.5°C between 24 and 72 hours following admission. Multiple logistic regression analyses were performed for the use of IVTM and survival at 90 days. Of the 302 patients identified, 136 (45%) were pre-TTM, and 166 (55%) post-TTM. Baseline characteristics were similar between the groups. IVTM use decreased significantly (77.9% vs. 51.8%, p < 0.001) after the publication of the TTM trial. Adherence to the 32-34°C and 32-36°C targets was higher pre-TTM as compared with the post-TTM cohort (33.3% [0-66.7%] vs. 0% [0-16.7%], p < 0.001 and 83.3% [50.0-100%] vs. 36.7% [16.7-66.7%], p < 0.001, respectively). Time with temperature ≥37.5°C in the first 24 hours was higher post-TTM (p = < 0.001) but not between 24 and 72 hours. Ninety-day survival was 54.4% in the pre-TTM cohort and 44.0% post-TTM, (odds ratio 1.52 [0.96-2.40], p = 0.083). Adherence with recommended TTM decreased significantly following publication of the TTM trial and this was explained by a significant decrease in IVTM use. However, this concerning trend did not result in a statistically significant difference in survival.

Introduction: The variability of acute respiratory distress syndrome management may affect the referral practice to severe respiratory failure centres. We described the management of acute respiratory distress syndrome in our catchment area. Methods: An electronic survey was administered to 42 intensive care units in South-East England. Results: Response rate was 71.4%. High-flow nasal oxygen and non-invasive ventilation were used 'often' in moderateacute respiratory distress syndrome by 46.7% and 60%. During invasive ventilation, 90% preferred pressure control, targeting tidal volumes of 6-8 ml/kg (53.3%) or 4-6 ml/kg (46.7%). Positive end-expiratory pressure was selected by positive end-expiratory pressure/inspiratory fraction of oxygen tables (50%) or decremental positive end-expiratory pressure trials (20%). Neuro-muscular blockers were widely used, although routinely by only 3.3%. High-frequency oscillatory ventilation (10%) and inhaled nitric oxide (13.3%) were rarely used. None used oesophageal manometry. Recruitment manoeuvres were used 'often' by 26.7%. Equipment (90%) and protocols (80%) for prone position were common, with sessions mostly lasting 12-18 h. Conclusions: Although variable, practice well reflected the available evidence. Proning was widely practiced with good availability of educational resources and protocolised care.

Background: Patients admitted to hospital with Covid-19 are at risk of deterioration. The National Early Warning Score (NEWS2) is widely recommended, however it's validity in Covid-19 is not established and indices more specific for respiratory failure may be more appropriate. We aim to describe the physiological antecedents to deterioration, test the predictive validity of NEWS2 and compare this to the ROX index ([SpO(2)/FiO(2)]/respiratory rate). Method: A single centre retrospective cohort study of adult patients who were admitted to a medical ward, between 1/3/20 and 30/5/20, with positive results for SARS-CoV-2 RNA. Physiological observations and the NEWS2 were extracted and analysed. The primary outcome was a composite of cardiac arrest, unplanned critical care admission or death within 24 hours. A generalized linear model was used to assess the association of physiological values, NEWS2 and ROX with the outcome. Findings: The primary outcome occurred in 186 patients (26%). In the preceding 24 hours, deterioration was most marked in respiratory parameters, specifically in escalating oxygen requirement; tachypnoea was a late sign, whilst cardiovascular observations remained stable. The area under the receiver operating curve was 0.815 (95% CI 0.804-0.826) for NEWS2 and 0.848 (95% CI 0.837-0.858) for ROX. Applying the optimal level of ROX, the majority of patients triggered four hours earlier than with NEWS2 of 5. Interpretation: NEWS2 may under-perform in Covid-19 due to intrinsic limitations of the design and the unique pathophysiology of the disease. A simple index utilising respiratory parameters can outperform NEWS2 in predicting the occurrence of adverse events. (c) 2021 The Authors. Published by Elsevier Ltd.

Background: High flow nasal cannula (HFNC) is commonly used post-extubation in intensive care (ICU). Patients’ comfort during HFNC is affected by flow rate: too low flow may limit the beneficial effects of HFNC on gas exchange and work of breathing; whilst excessive flow may reduce comfort and adherence to therapy. Currently, there is no consensus on how to set the flow rate of HFNC post-extubation. The study aims to describe the relationship between pre-extubation inspiratory flow requirements and the post-extubation flow rates on HFNC that maximises patient’s level of comfort. Methods: This was an observational, retrospective, single-site study conducted in a tertiary, university-affiliated ICU. We included all patients extubated following a successful, standardised spontaneous breathing trial (SBT) during a four-month study period. During a 30-minute SBT we recorded haemodynamic and respiratory variables including inspiratory flow, presence of any signs of respiratory distress and level of comfort using a visual analogue scale (VAS). Patients who passed the SBT were extubated onto HFNC – as per standard clinical practice. HFNC was titrated starting from a flow of 20 L/min and increased in steps of 10L/min, up to 60 L/min or maximum tolerated flow. At each step, patient’s level of comfort was assessed using a VAS. Fraction of inspired oxygen (FiO 2 ) was titrated to maintain oxygen saturation measured by pulse oximetry (SpO 2 ) 92-97%. Results : Nineteen participants were enrolled in the study with a mean (SD) age of 62.5 ± 13.1 years. There was a significant positive correlation between mean inspiratory flow pre-extubation and the flow setting on HFNC which achieved the best comfort post-extubation (r 2 0.88; p <0.001). The greatest comfort was observed for HFNC flows between 30 and 40 L/min, while above 40 L/min patients’ comfort decreased. Conclusions : Measuring mean inspiratory flow during an SBT allows for individualised setting of HFNC flow rate immediately post-extubation and achieves the greatest comfort and interface tolerance.

Background Rapid response systems aim to achieve a timely response to the deteriorating patient; however, the existing literature varies on whether timing of escalation directly affects patient outcomes. Prior studies have been limited to using ‘decision to admit’ to critical care, or arrival in the emergency department as ‘time zero’, rather than the onset of physiological deterioration. The aim of this study is to establish if duration of abnormal physiology prior to critical care admission [‘Score to Door’ (STD) time] impacts on patient outcomes. Methods A retrospective cross-sectional analysis of data from pooled electronic medical records from a multi-site academic hospital was performed. All unplanned adult admissions to critical care from the ward with persistent physiological derangement [defined as sustained high National Early Warning Score (NEWS) > / = 7 that did not decrease below 5] were eligible for inclusion. The primary outcome was critical care mortality. Secondary outcomes were length of critical care admission and hospital mortality. The impact of STD time was adjusted for patient factors (demographics, sickness severity, frailty, and co-morbidity) and logistic factors (timing of high NEWS, and out of hours status) utilising logistic and linear regression models. Results Six hundred and thirty-two patients were included over the 4-year study period, 16.3% died in critical care. STD time demonstrated a small but significant association with critical care mortality [adjusted odds ratio of 1.02 (95% CI 1.0–1.04, p = 0.01)]. It was also associated with hospital mortality (adjusted OR 1.02, 95% CI 1.0–1.04, p = 0.026), and critical care length of stay. Each hour from onset of physiological derangement increased critical care length of stay by 1.2%. STD time was influenced by the initial NEWS, but not by logistic factors such as out-of-hours status, or pre-existing patient factors such as co-morbidity or frailty. Conclusion In a strictly defined population of high NEWS patients, the time from onset of sustained physiological derangement to critical care admission was associated with increased critical care and hospital mortality. If corroborated in further studies, this cohort definition could be utilised alongside the ‘Score to Door’ concept as a clinical indicator within rapid response systems.