Comparison of three lung recruitment maneuvers in the treatment of severe extra-pulmonary acute respiratory distress syndrome

Objective To investigate the efficacy and side effects of three recruitment maneuvers (RM) for severe extra-pulmonary acute respiratory distress syndrome (ARDS). Methods A total of sixty-three extra-pulmonary ARDS patients were enrolled and randomly divided into three groups, which were treated with sustained inflation (SI), increment of positive end-expiratory pressure (IP) and pressure control ventilation (PCV) respectively.The oxygenation index (PaO2/FiO2) before and after lung recruitment was recorded in patients with complete lung recruitment, and the cause of discontinuation of lung recruitment was recorded in patients with incomplete lung recruitment.Positive end-expiratory pressure (PEEP) was recorded in patients who completed lung recruitment with the latter two methods when they reached the maximum degree of lung recruitment.The mortality rate of 14 d in 3 groups was recorded, and the clinical characteristics and prognosis differences were compared before and after each group. Results With PaO2/FiO2 as the standard, all the three methods of pulmonary reexpansion could make the lungs obviously reexpanse.The PaO2/FiO2 of each group before, 5 minutes after and 1 hour after reexpansion were respectively as below (SI group: 70.4±14.8 mmHg, 306.8±97.5 mmHg, 229.6±116.2 mmHg; IP group: 74.9±13.6 mmHg, 328.0±95.5 mmHg, 252.8±111.0 mmHg; PCV group: 67.8±14.9 mmHg, 304.2±82.2 mmHg, 223.7±83.6 mmHg.P 0.05). PEEP of IP group is higher than that of PCV group at the time of maximum RM (20.3±2.5 cmH2O vs.18.5±1.8 cmH2O, P 0.05). Conclusion The effects of three methods of lung recruitment on severe pulmonary exogenous ARDS patients were similar, but there was no significant difference in prognosis.Adverse reactions of SI method leads to the greatest probability of discontinuation of lung recruitment, and that of the PCV method is the smallest.Under the same effect of lung recruitment, IP method needs higher PEEP than PCV method.In practice, PCV method should be preferred. Key words: Acute respiratory distress syndrome; Recruitment maneuvers; Sustained inflation; Increment PEEP; Pressure control ventilation