Pan Chun, Chen Lu, Zhang Yun-Hang, Liu Wei, Urbino Rosario, Ranieri V Marco, Qiu Hai-Bo, Yang Yi
Department of Critical Care Medicine, Zhongda Hospital, Medical School, Southeast University, Nanjing, Jiangsu 210009, China.
Department of Critical Care Medicine, Beijing Tiantan Hospital, Capital Medical University, Beijing 100050, China.
Chin Med J (Engl). 2016 Jul 20;129(14):1652-7. doi: 10.4103/0366-6999.185855.
Stress index at post-recruitment maneuvers could be a method of positive end-expiratory pressure (PEEP) titration in acute respiratory distress syndrome (ARDS) patients. However, airway pressure (Paw) stress index may not reflect lung mechanics in the patients with high chest wall elastance. This study was to evaluate the Pawstress index on lung mechanics and the correlation between Pawstress index and transpulmonary pressure (PL) stress index in acute respiratory failure (ARF) patients.
Twenty-four ARF patients with mechanical ventilation (MV) were consecutively recruited from July 2011 to April 2013 in Zhongda Hospital, Nanjing, China and Ospedale S. Giovanni Battista-Molinette Hospital, Turin, Italy. All patients underwent MV with volume control (tidal volume 6 ml/kg) for 20 min. PEEP was set according to the ARDSnet study protocol. The patients were divided into two groups according to the chest wall elastance/respiratory system elastance ratio. The high elastance group (H group, n = 14) had a ratio ≥30%, and the low elastance group (L group, n = 10) had a ratio <30%. Respiratory elastance, gas-exchange, Pawstress index, and PLstress index were measured. Student's t-test, regression analysis, and Bland-Altman analysis were used for statistical analysis.
Pneumonia was the major cause of respiratory failure (71.0%). Compared with the L group, PEEP was lower in the H group (5.7 ± 1.7 cmH2O vs. 9.0 ± 2.3 cmH2O, P < 0.01). Compared with the H group, lung elastance was higher (20.0 ± 7.8 cmH2O/L vs. 11.6 ± 3.6 cmH2O/L, P < 0.01), and stress was higher in the L group (7.0 ± 1.9 vs. 4.9 ± 1.9, P = 0.02). A linear relationship was observed between the Pawstress index and the PLstress index in H group (R2 = 0.56, P < 0.01) and L group (R2 = 0.85, P < 0.01).
In the ARF patients with MV, Pawstress index can substitute for PLto guide ventilator settings.
ClinicalTrials.gov NCT02196870 (https://clinicaltrials.gov/ct2/show/NCT02196870).
在急性呼吸窘迫综合征（ARDS）患者中，复张手法后的应力指数可能是一种呼气末正压（PEEP）滴定方法。然而，气道压力（Paw）应力指数可能无法反映胸壁弹性较高患者的肺力学情况。本研究旨在评估急性呼吸衰竭（ARF）患者中Paw应力指数对肺力学的影响以及Paw应力指数与跨肺压（PL）应力指数之间的相关性。
2011年7月至2013年4月，在中国南京的中大医院和意大利都灵的圣乔瓦尼·巴蒂斯塔-莫利内特医院连续招募了24例接受机械通气（MV）的ARF患者。所有患者接受容量控制通气（潮气量6 ml/kg）20分钟。根据ARDSnet研究方案设置PEEP。根据胸壁弹性/呼吸系统弹性比值将患者分为两组。高弹性组（H组，n = 14）比值≥30%，低弹性组（L组，n = 10）比值<30%。测量呼吸弹性、气体交换、Paw应力指数和PL应力指数。采用学生t检验、回归分析和Bland-Altman分析进行统计分析。
肺炎是呼吸衰竭的主要原因（71.0%）。与L组相比，H组的PEEP较低（5.7±1.7 cmH₂O对9.0±2.3 cmH₂O，P<0.01）。与H组相比，L组的肺弹性较高（20.0±7.8 cmH₂O/L对11.6±3.6 cmH₂O/L，P<0.01），应力也较高（7.0±1.9对4.9±1.9，P = 0.02）。在H组（R² = 0.56，P<0.01）和L组（R² = 0.85，P<0.01）中，观察到Paw应力指数与PL应力指数之间存在线性关系。
在接受MV的ARF患者中，Paw应力指数可替代PL来指导呼吸机设置。
ClinicalTrials.gov NCT02196870（https://clinicaltrials.gov/ct2/show/NCT02196870）。
