Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Saving lives: the civil military response to the 2014 Ebola outbreak in West Africa

The 2014 Ebola outbreak in Guinea, Liberia and Sierra Leone proved to be an exceptional outbreak that blurred the lines between health and humanitarian crises. In so doing, it highlighted numerous problems with regard to the coordination of humanitarian disasters that have public health implications of international consequence. The manner in which the international response to this crisis unfolded has in turn prompted a number of high-level intergovernmental reviews of the key actors, institutions and systems that we - as a global community - currently rely upon. At the time of writing, some of these reviews are yet to hand down their findings. This study, which was funded by the University of Sydney, provides a number of independent insights into the civil-military response and overall coordination of the Ebola outbreak in Liberia and Sierra Leone. It also offers recommendations to inform future research and response efforts. The domestic health systems of Liberia and Sierra Leone were ill-equipped to address the size and scale of the Ebola outbreak. Overwhelmed, rapid international assistance was needed to halt the spread of the virus and save lives. The international civilian response to this crisis was, however, widely perceived as slow and inadequate. While key institutions such as the World Health Organization (WHO) have been heavily criticized, the role of non-government organizations (NGOs) was also mixed. A small number of non-state actors and international NGOs (INGOs) such as Medicines Sans Frontiers (MSF) reacted swiftly to the outbreak, but the majority of other organizations found themselves unprepared for a crisis of this nature, withdrawing personnel and closing down operations. This raises serious concerns about the overall capacity of the existing humanitarian system and agencies to respond to health-related crises. Due to the inadequate civilian response, the 2014 Ebola outbreak also witnessed the deployment of thousands of military personnel to help contain the outbreak. The majority of respondents interviewed for this study were positive about the role of foreign military assistance (FMA), which was seen as a necessary last resort. In addition, Sierra Leoneans were generally positive about the role of domestic armed forces, which played a larger role in the Ebola response than their Liberian counterparts. However, several significant criticisms and concerns emerged as well. Foreign armed forces were perceived as risk averse and slow in constructing Ebola Treatment Units (ETUs). Criticism of domestic armed forces included the threat - and in some instances use of - violence and intimidation. Strong leadership from the President and the health sector in Liberia was recognised as key to the country’s effective response, whereas weak leadership and patronage within the health sector was seen to hurt the response in Sierra Leone. Limited trust in government undermined public health, inhibiting behavioural change and social awareness campaigns (particularly in Sierra Leone). These findings highlight that changes are warranted in how governments, international organisations, NGOs, civil society and even militaries approach health-related humanitarian crises in the future

Immunocompromised patients with acute respiratory distress syndrome : Secondary analysis of the LUNG SAFE database

The aim of this study was to describe data on epidemiology, ventilatory management, and outcome of acute respiratory distress syndrome (ARDS) in immunocompromised patients. Methods: We performed a post hoc analysis on the cohort of immunocompromised patients enrolled in the Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) study. The LUNG SAFE study was an international, prospective study including hypoxemic patients in 459 ICUs from 50 countries across 5 continents. Results: Of 2813 patients with ARDS, 584 (20.8%) were immunocompromised, 38.9% of whom had an unspecified cause. Pneumonia, nonpulmonary sepsis, and noncardiogenic shock were their most common risk factors for ARDS. Hospital mortality was higher in immunocompromised than in immunocompetent patients (52.4% vs 36.2%; p < 0.0001), despite similar severity of ARDS. Decisions regarding limiting life-sustaining measures were significantly more frequent in immunocompromised patients (27.1% vs 18.6%; p < 0.0001). Use of noninvasive ventilation (NIV) as first-line treatment was higher in immunocompromised patients (20.9% vs 15.9%; p = 0.0048), and immunodeficiency remained independently associated with the use of NIV after adjustment for confounders. Forty-eight percent of the patients treated with NIV were intubated, and their mortality was not different from that of the patients invasively ventilated ab initio. Conclusions: Immunosuppression is frequent in patients with ARDS, and infections are the main risk factors for ARDS in these immunocompromised patients. Their management differs from that of immunocompetent patients, particularly the greater use of NIV as first-line ventilation strategy. Compared with immunocompetent subjects, they have higher mortality regardless of ARDS severity as well as a higher frequency of limitation of life-sustaining measures. Nonetheless, nearly half of these patients survive to hospital discharge. Trial registration: ClinicalTrials.gov, NCT02010073. Registered on 12 December 2013