Past and Present ARDS Mortality Rates: A Systematic Review

Abstract

ARDS is severe form of respiratory failure with significant impact on the morbidity and mortality of critical care patients. Epidemiological data are crucial for evaluating the efficacy of therapeutic interventions, designing studies, and optimizing resource distribution. The goal of this review is to present general aspects of mortality data published over the past decades. A systematic search of the MEDLINE/PubMed was performed. The articles were divided according to their methodology, type of reported mortality, and time. The main outcome was mortality. Extracted data included study duration, number of patients, and number of centers. The mortality trends and current mortality were calculated for subgroups consisting of in-hospital, ICU, 28/30-d, and 60-d mortality over 3 time periods (A, before 1995; B, 1995-2000; C, after 2000). The retrospectivity and prospectivity were also taken into account. Moreover, we present the most recent mortality rates since 2010. One hundred seventy-seven articles were included in the final analysis. General mortality rates ranged from 11 to 87% in studies including subjects with ARDS of all etiologies (mixed group). Linear regression revealed that the study design (28/30-d or 60-d) significantly influenced the mortality rate. Reported mortality rates were higher in prospective studies, such as randomized controlled trials and prospective observational studies compared with retrospective observational studies. Mortality rates exhibited a linear decrease in relation to time period (P < .001). The number of centers showed a significant negative correlation with mortality rates. The prospective observational studies did not have consistently higher mortality rates compared with randomized controlled trials. The mortality trends over 3 time periods (before 1995, 1995-2000, and after 2000) yielded variable results in general ARDS populations. However, a mortality decrease was present mostly in prospective studies. Since 2010, the overall rates of in-hospital, ICU, and 28/30-d and 60-d mortality were 45, 38, 30, and 32%, respectively.

Prevention and treatment of acute lung injury with time-controlled adaptive ventilation: physiologically informed modification of airway pressure release ventilation

“…The ARDSnet Low Vt (LVt) method is intended to protect the non-dependent normal lung tissue from overdistension (OD) and reduce alveolar recruitment/ derecruitment (R/D) with positive end expiratory pressure (PEEP), while resting severely injured tissue by allowing it to remain collapsed throughout the ventilation cycle [2]. However, this strategy has not further reduced ARDS mortality [1,[3][4][5][6][7][8][9][10][11]. This suggests that our understanding of ARDS pathophysiology remains [12] all using the airway pressure release ventilation (APRV) mode but with different methods: a Stock et al used a CPAP phase that encompassed 60% of each breath, a release phase of 1.27 s and a respiratory rate (RR) of 20/min [98]; b Davis et al decreased the respiratory rate by prolonging both the CPAP and release phase [99]; c Gama de Abreau et al adjusted their CPAP and release phase to values typical of a conventional breath [100]; d Roy et al minimized the release phase and extended CPAP to occupy 90% of each breath, typical of the time-controlled adaptive ventilation (TCAV) method [83].…”

“…Current ARDS treatment is supportive: protective mechanical ventilation, typically using lower tidal volume ventilation (Vt) and low-moderate positive end expiratory pressure (PEEP) [2]. Unfortunately, current protective ventilation strategies have not lessened ARDS mortality rate [1,[3][4][5][6][7][8][9][10][11]. The determinant of VILI is not the "mode" of ventilation, but the way parameters of the mechanical breath are set and combined.…”

Lipopolysaccharide-induced endotoxemia in corn oil-preloaded mice causes an extended course of lung injury and repair and pulmonary fibrosis: A translational mouse model of acute respiratory distress syndrome

“…Acute respiratory distress syndrome (ARDS) remains a major cause of mortality in intensive care units worldwide [1–3]. The triggers of ARDS can be classified as direct (e.g.…”

“…in two-thirds of ARDS patients) [7–9]. Although the incidence and mortality of ARDS has declined over recent years [3, 10], the mechanisms that regulate the pathogenesis and resolution of ARDS are incompletely understood, and there are still no effective pharmacological or cell-based treatments for this disease.…”

Safety of hyperbaric oxygen therapy in mechanically ventilated patients

“…Additionally, our HBOT protocol proposed a compression to 3.8 absolute atmospheres, leading to a ppO 2 that reached 380 kPa. In our work, the mortality in the ARDS group is 23% which is not higher from noticed rates (11% to 87%) in the general literature, including all aetiologies [22].…”