Impact of "opening the lung" ventilatory strategy on burn patients with acute respiratory distress syndrome

Abstract

Objective: The objective of this study was to investigate the feasibility and influence of opening the lung strategy ventilation on burned patients complicated with ARDS.

Methods: A prospective study was carried out in 66 moderate to severe burned patients also presented with ARDS who were randomly divided into the control group (ventilated as ARDS net) and the study group (ventilated with open lung strategy). All patients were ventilated with volume control mode until weaning.

Results: Opening the lung procedure was safe in all patients with optimal PEEP of 14.8 ± 1.8 cmH₂O. After 24 h of lung recruitment and PEEP titration, oxygenation significantly improved (PaO₂/FiO₂ ratio increased from 119.8 ± 7.4 to 263.4 ± 11.6; p < 0.01). Along the time, the absolute values of static compliances in the study group were significantly higher (33.9 ± 0.9 vs. 26.3 ± 0.6 at 1st day; 48.4 ± 1.5 vs. 35.7 ± 0.8 at 3rd day; 48.2 ± 1.5 vs. 42.6 ± 1 at 5th day and 53.2 ± 1.8 vs. 45.3 ± 2.3 at 7th day). In addition, within the first 5 days of ventilation, PaO₂/FiO₂ ratio significantly increased in both groups (p < 0.05) but a faster rate was recorded in the study group (176.2 ± 11.9 vs. 152.1 ± 7.5 at 1st day; 284.2 ± 16.7 vs. 210.8 ± 15.3 at 3rd day and 302.2 ± 21 vs. 233.7 ± 22.4 at 5th day, p < 0.05). Number of ventilator-free days during the first 28-days after burn injury was significantly higher in the study group (12.9 ± 5.7 vs. 9.5 ± 5.9 days; p < 0.05). Ventilation time, lengths of stay in the ICU and hospital length of stay were not significantly different across both groups (p > 0.05). In addition, duration time from ADRS onset to death and from admission to death were also remarkably longer in the study group (p < 0.05). Mortality rate was significant lower in the study group (24.2% vs. 63.6%; p < 0.01) within 7 days since onset of ARDS, but not significantly different after two weeks as well as at the 28th day after burns injury. Overall mortality rate was also not significant difference between two groups.

Conclusion: It is necessary to conduct further trials to find out the effectiveness of this ventilation strategy on burns injury induced ARDS.

Keywords: ARDS; Burns; Open lung strategy; Outcomes.