Cinnella Gilda, Grasso Salvatore, Raimondo Pasquale, D'Antini Davide, Mirabella Lucia, Rauseo Michela, Dambrosio Michele
From the Department of Anaesthesia and Intensive Care, University of Foggia, Foggia, Italy (G.C., P.R., D.D., L.M., M.R., M.D.); and Department of Anaesthesia and Intensive Care, University of Bari, Bari, Italy (S.G.).
Anesthesiology. 2015 Nov;123(5):1113-21. doi: 10.1097/ALN.0000000000000862.
To test the hypothesis that in early, mild, acute respiratory distress syndrome (ARDS) patients with diffuse loss of aeration, the application of the open lung approach (OLA) would improve homogeneity in lung aeration and lung mechanics, without affecting hemodynamics.
Patients were ventilated according to the ARDS Network protocol at baseline (pre-OLA). OLA consisted in a recruitment maneuver followed by a decremental positive end-expiratory pressure trial. Respiratory mechanics, gas exchange, electrical impedance tomography (EIT), cardiac index, and stroke volume variation were measured at baseline and 20 min after OLA implementation (post-OLA). Esophageal pressure was used for lung and chest wall elastance partitioning. The tomographic lung image obtained at the fifth intercostal space by EIT was divided in two ventral and two dorsal regions of interest (ROIventral and ROIDorsal).
Fifteen consecutive patients were studied. The OLA increased arterial oxygen partial pressure/inspired oxygen fraction from 216 ± 13 to 311 ± 19 mmHg (P < 0.001) and decreased elastance of the respiratory system from 29.4 ± 3 cm H2O/l to 23.6 ± 1.7 cm H2O/l (P < 0.01). The driving pressure (airway opening plateau pressure - total positive end-expiratory pressure) decreased from 17.9 ± 1.5 cm H2O pre-OLA to 15.4 ± 2.1 post-OLA (P < 0.05). The tidal volume fraction reaching the dorsal ROIs increased, and consequently the ROIVentral/Dorsal impedance tidal variation decreased from 2.01 ± 0.36 to 1.19 ± 0.1 (P < 0.01).
The OLA decreases the driving pressure and improves the oxygenation and lung mechanics in patients with early, mild, diffuse ARDS. EIT is useful to assess the impact of OLA on regional tidal volume distribution.
为验证以下假设：对于早期、轻度、急性呼吸窘迫综合征（ARDS）且存在弥漫性通气丧失的患者，采用开放肺策略（OLA）可改善肺通气的均匀性和肺力学，且不影响血流动力学。
患者在基线时（OLA前）按照ARDS网络方案进行通气。OLA包括一次肺复张手法，随后进行递减式呼气末正压试验。在基线和实施OLA后20分钟（OLA后）测量呼吸力学、气体交换、电阻抗断层扫描（EIT）、心脏指数和每搏量变异。食管压力用于肺和胸壁弹性的划分。通过EIT在第五肋间获得的断层肺图像被分为两个腹侧和两个背侧感兴趣区域（ROIventral和ROIDorsal）。
连续研究了15例患者。OLA使动脉血氧分压/吸入氧分数从216±13mmHg提高到311±19mmHg（P<0.001），并使呼吸系统弹性从29.4±3cmH₂O/L降至23.6±1.7cmH₂O/L（P<0.01）。驱动压力（气道开口平台压 - 总呼气末正压）从OLA前的17.9±1.5cmH₂O降至OLA后的15.4±2.1cmH₂O（P<0.05）。到达背侧ROI的潮气量分数增加，因此ROIVentral/Dorsal阻抗潮气量变异从2.01±0.36降至1.19±0.1（P<0.01）。
OLA可降低驱动压力，并改善早期、轻度、弥漫性ARDS患者的氧合和肺力学。EIT有助于评估OLA对区域潮气量分布的影响。
