급성호흡곤란증후군 환자에서 폐포모집술의 반응에 따른 초기 예후의 차이

Abstract

Background: Lung protective strategies, using low tidal volume in ARDS, improve survival rate in ARDS. However, low tidal volume ventilation may promote alveolar de-recruitment. Therefore, alveolar recruitment is necessary to maintain arterial oxygenation and to prevent repetitive opening and closure of collapsed alveoli in lung protective strategies. There has been a recent report describing improvement in arterial oxygenation with use of recruitment maneuver. However, impact of recruitment on outcome of ARDS is unknown. We evaluated whether short-term survival difference existed in patients with ARDS, who were performed alveolar recruitment maneuver(ARM) and prone position, according to response of alveolar recruitment or not. Methods: All patients who were diagnosed with ADRS and received mechanical ventilation were included. ARM were sustained inflation(35-45 cmH2O CPAP for 30-40 sec.) or increasing level of PEEP. If these methods were ineffective, alveolar recruitment with prone position was done for at least 10 hours. PaO 2/FiO2(P/F) ratio was determined before and at 0.5 and 2 hours after ARM. We defined a responder if the P/F ratio was increased over 50% of baseline value. We compared 10-days and 30-days survival rate between responders and non-responders. Results: 20 patients(M:F=12:8, 63±14 age) were included. Among them, 12 patients were responders and 8 patients were non-responders. In responders, P/F ratio was increased from 92±25 mmHg to 244±85 mmHg. In non-responders, P/F ratio increased from 138±37 mmHg to 163±60 mmHg. Among non-responders, P/F ratio was improved over 50% in 2 patients after prone position. Overall, 14 patients were responders after ARM and prone position. The 10-days and 30-days survival rate in responders was significantly higher than in non-responders(86%, 57% in responders and 33%, 0% in non-responders)(p<0.05). There was no significant difference between responders and non-responders in age(71±11, 60±14), lung injury score(2.8±0.2, 2.9±0.45), simplified acute physiology score(SAPS) II (35±4.6, 34±5.7), positive end-positive pressure level(15.6±1.9 cmH2O, 14.5±2.1 cmH2O). Conclusion: ARM may improve arterial oxygenation in some patients with ARDS. These responders in patients with ARDS showed significant higher 10-days and 30-days survival rate than non-responders patients with alveolar recruitment.