Abstract: Objective To explore the effects of low tidal volume mechanical ventilation combined with lung recruitment maneuver in patients with acute severe organophosphorus pesticide poisoning.Methods Analysis of 48 cases with acute severe dichlorphos poisoning, all patients were treated with mechanical ventilation because of respiratory failure.These patient were randomly assigned to the standard ventilation group and the protective ventilation group with 24 cases in each group. The patients of the standard ventilation group were received a tidal volume of 10 mL/kg ideal body weight and 3 cmH₂O positive end-expiratory pressure. The patients of the protective ventilation group were received a tidal volume of 6 mL/kg ideal body weight and 6 cmH₂O positive end-expiratory pressure,and implementing twice lung recruitment maneuver per day.Blood gas analysis parameters. Indicators of pulmonary infection(clinicalpulmonary infection scoreCPIS, C-reactive protein CRP, procalcitonin PCT)and atelectasis were recorded after 24 h and 72 h mechanical ventilation. Results After mechanical ventilation 24 h and 72 h, indicators of pulmonary infection in protective ventilation group were significantly lower than that of thestandard ventilation group, the difference was statistically significant(P<0.05). Oxygen partial pressure(PO₂)and oxygenation index in protective ventilation group were significantly higher than that of thestandard ventilation group(P<0.05). There was no significant difference in the incidence of atelectasis between the two groups(P>0.05).Conclusion Protective ventilation strategy can reduce the risk of pulmonary infection and improve oxygenation,but can not reduce the occurrence of atelectasis in patients with acute severe organophosphorus pesticide poisoning.

Key words: low tidal volume, lung recruitment maneuver, atelectasis, organophosphorus pesticide poisoning