Practice of diagnosis and management of acute respiratory distress syndrome in mainland China: a cross-sectional study

Abstract

Background: Although acute respiratory distress syndrome (ARDS) has been recognized for more than 50 years, limited information exists about the incidence and management of ARDS in mainland China. To evaluate the potential for improvement in management of patients with ARDS, this study was designed to describe the incidence and management of ARDS in mainland China.

Methods: National prospective multicenter observational study over one month (August 31^st to September 30^th, 2012) of all patients who fulfilled the Berlin or American European Consensus Conference (AECC) definition of ARDS in 20 intensive care units, with data collection related to the management of ARDS, patient characteristics and outcomes.

Results: Of the 1,814 patients admitted during the enrollment period, 149 (8.2%) and 147 (8.1%) patients were diagnosed by AECC and Berlin definition, respectively. Lung protective strategy with low tidal volume (Vt) (≤8 mL/kg) and limitation of the plateau pressure (Pplat) (≤30 cmH₂O) was performed in 75.2% patients. And, 36%, 21.1% and 4.1% patients with severe, moderate and mild ARDS had the driving pressure more than 14 cmH₂O (P<0.05). Pplat and driving pressure increased significantly in patients with a higher degree of ARDS severity (P=0.002 and P<0.001, respectively), but Vt were comparable in the three groups (P>0.05). In severe ARDS, patient median positive end expiratory pressure (PEEP) was 10.0 (8.0-11.3) cmH₂O and median FiO₂ was 90%. A recruitment maneuver was performed in 35.5% of the patients, and 8.7% of patients with severe ARDS received prone position. Overall hospital mortality was 34.0%. Hospital mortality was 21.8% for mild, 31.1% for moderate, and 60.0% for patients with severe ARDS (P=0.004).

Conclusions: Despite general acceptance of low Vt and limited Pplat, high driving pressure, low PEEP and low use of adjunctive measures may still be a concern in mainland China, especially in patients with severe ARDS.

Trial registration: ClinicalTrials.gov NCT01666834; date of registration release: August 14^th 2012.

Keywords: Clinical epidemiology; acute respiratory distress syndrome (ARDS); mechanical ventilation; mortality.

Figure 1

Flow diagram of patient screening and enrollment. ARDS, Although acute respiratory distress syndrome; COPD, chronic obstructive pulmonary disease; PEEP, positive end-expiratory pressure; HFNC, XXXXXXX; AECC, American European Consensus Conference.

Figure 2

Cumulative frequency distribution of ventilation parameters by acute respiratory distress syndrome (ARDS) severity. (A) Cumulative frequency distribution of tidal volume was similar in patients in each severity category, with 75.6% of patients with ARDS receiving a tidal volume of 8 mL/kg of predicted body weight or less; (B) in contrast, a right shift of the cumulative frequency distribution curves of ∆P was seen for more severe ARDS category, with ∆P ≤14 cmH₂O in 72.6% of patients.

Figure 3

Relationship between ventilation parameters and respiratory compliance. (A) There was a weak but statistically significant positive correlation between tidal volume and respiratory compliance (R²=0.195, P<0.001); (B) no correlation was found between positive end expiratory pressure and respiratory compliance (R²=0.001, P=0.706). PEEP, positive end-expiratory pressure.

Figure 4

Probability of hospital survival by ARDS severity and ∆P. (A) There was a lower likelihood of survival to day 28 with severe acute respiratory distress syndrome (ARDS) on day 1. Survival to day 28 was not different between mild and moderate ARDS patients; (B) patients with a ∆P >14 cmH2O on day 1 of ARDS criteria had a higher mortality.