Outcome of acute respiratory distress syndrome in university and non-university hospitals in Germany

Abstract

BackgroundThis study investigates differences in treatment and outcome of ventilated patients with acute respiratory distress syndrome (ARDS) between university and non-university hospitals in Germany.MethodsThis subanalysis of a prospective, observational cohort study was performed to identify independent risk factors for mortality by examining: baseline factors, ventilator settings (e.g., driving pressure), complications, and care settings—for example, case volume of ventilated patients, size/type of intensive care unit (ICU), and type of hospital (university/non-university hospital). To control for potentially confounding factors at ARDS onset and to verify differences in mortality, ARDS patients in university vs non-university hospitals were compared using additional multivariable analysis.ResultsOf the 7540 patients admitted to 95 ICUs from 18 university and 62 non-university hospitals in May 2004, 1028 received mechanical ventilation and 198 developed ARDS. Although the characteristics of ARDS patients were very similar, hospital mortality was considerably lower in university compared with non-university hospitals (39.3% vs 57.5%; p = 0.012). Treatment in non-university hospitals was independently associated with increased mortality (OR (95% CI): 2.89 (1.31–6.38); p = 0.008). This was confirmed by additional independent comparisons between the two patient groups when controlling for confounding factors at ARDS onset. Higher driving pressures (OR 1.10; 1 cmH2O increments) were also independently associated with higher mortality. Compared with non-university hospitals, higher positive end-expiratory pressure (PEEP) (mean ± SD: 11.7 ± 4.7 vs 9.7 ± 3.7 cmH2O; p = 0.005) and lower driving pressures (15.1 ± 4.4 vs 17.0 ± 5.0 cmH2O; p = 0.02) were applied during therapeutic ventilation in university hospitals, and ventilation lasted twice as long (median (IQR): 16 (9–29) vs 8 (3–16) days; p < 0.001).ConclusionsMortality risk of ARDS patients was considerably higher in non-university compared with university hospitals. Differences in ventilatory care between hospitals might explain this finding and may at least partially imply regionalization of care and the export of ventilatory strategies to non-university hospitals.Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-017-1687-0) contains supplementary material, which is available to authorized users.

Quality of inter-hospital transportation in 431 transport survivor patients suffering from acute respiratory distress syndrome referred to specialist centers

“…In this study the majority of ARDS patients (85%) were transported to ARDS/ECMO centers for further treatment. Patients with a severe ARDS and potentially reversible respiratory failure may have a better chance to survive when transported to an ECMO center [17–19]. …”

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].…”

“…The current understanding is that open and collapsed tissues are not delineated into compartments, but are rather intermingled throughout the entire lung [17][18][19][20][21]. The unchanged mortality associated with the LVt method may also reflect the fact that maintaining lung tissue collapse ("resting") may not be protective [1,[3][4][5][6][7][8][9][10][11]. The atelectatic lung does not exchange gas, is susceptible to pneumonia, and may ultimately lead to collapse induration and fibrosis with the inability to re-inflate or epithelialize the airspace [22][23][24].…”

“…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.…”

A Physiologically Informed Strategy to Effectively Open, Stabilize, and Protect the Acutely Injured Lung

“…It was not until the ARDS Network (ARDSnet) conducted the seminal ARMA study, published in 2000, that a reduction in mortality was shown (Acute Respiratory Distress Syndrome Network, 2000). However, most (Phua et al, 2009;Villar et al, 2011;Caser et al, 2014;Bellani et al, 2016;Laffey et al, 2016;Villar et al, 2016;Maca et al, 2017;Raymondos et al, 2017;Rezoagli et al, 2017;Fan et al, 2018;McNicholas et al, 2018;Pham et al, 2019;Shen et al, 2019) but not all (Brun-Buisson et al, 2004;Fan et al, 2005;Putensen et al, 2009;Petrucci and De Feo, 2013;Shen et al, 2019) of the recent statistical-and meta-analyses have shown that ARDS mortality has not been reduced below the 31% "gold standard" of the 2000 ARMA study but rather remains unacceptably high at ∼40% (Figure 1). Despite these disappointing results, the low-Vt ARDSnet method is still recommended as the standard-of-care protective ventilation strategy for ARDS patients (Fan et al, 2017(Fan et al, , 2018Papazian et al, 2019).…”