个体化呼气末正压通气对猪肺损伤时区域性气体交换的影响。

Individualized Positive End-expiratory Pressure and Regional Gas Exchange in Porcine Lung Injury.

机构信息

From the Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Germany (T.Muders, H.L., J.Z., S.K., C.P.) the Department of Anesthesiology and Intensive Care Medicine, University of Schleswig Holstein, Campus Lübeck, Germany (T.Meier) the Department of Anesthesiology and Intensive Care Medicine, University of Leipzig, Germany (A.W.R.) the Federal Institute for Drugs and Medical Devices/Bundesinstitut für Arzneimittel und Medizinprodukte (BfArM), Bonn, Germany (J.Z.) the Philips Chair for Medical Information Technology, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany (R.P., S.L.) the Department of Medical Physics University Hospital, Uppsala, Sweden (E.M.) the Department of Medical Sciences, Clinical Physiology, Uppsala University, Sweden (G.H.) the Department of Anesthesiology, Intensive Care and Emergency Medicine, Pain Therapy; Bergmannstrost Hospital Halle, Halle, Germany (H.W.).

出版信息

Anesthesiology. 2020 Apr;132(4):808-824. doi: 10.1097/ALN.0000000000003151.

DOI:10.1097/ALN.0000000000003151

PMID:32101968

Abstract

BACKGROUND

In acute respiratory failure elevated intraabdominal pressure aggravates lung collapse, tidal recruitment, and ventilation inhomogeneity. Low positive end-expiratory pressure (PEEP) may promote lung collapse and intrapulmonary shunting, whereas high PEEP may increase dead space by inspiratory overdistension. The authors hypothesized that an electrical impedance tomography-guided PEEP approach minimizing tidal recruitment improves regional ventilation and perfusion matching when compared to a table-based low PEEP/no recruitment and an oxygenation-guided high PEEP/full recruitment strategy in a hybrid model of lung injury and elevated intraabdominal pressure.

METHODS

In 15 pigs with oleic acid-induced lung injury intraabdominal pressure was increased by intraabdominal saline infusion. PEEP was set in randomized order: (1) guided by a PEEP/inspired oxygen fraction table, without recruitment maneuver; (2) minimizing tidal recruitment guided by electrical impedance tomography after a recruitment maneuver; and (3) maximizing oxygenation after a recruitment maneuver. Single photon emission computed tomography was used to analyze regional ventilation, perfusion, and aeration. Primary outcome measures were differences in PEEP levels and regional ventilation/perfusion matching.

RESULTS

Resulting PEEP levels were different (mean ± SD) with (1) table PEEP: 11 ± 3 cm H2O; (2) minimal tidal recruitment PEEP: 22 ± 3 cm H2O; and (3) maximal oxygenation PEEP: 25 ± 4 cm H2O; P < 0.001. Table PEEP without recruitment maneuver caused highest lung collapse (28 ± 11% vs. 5 ± 5% vs. 4 ± 4%; P < 0.001), shunt perfusion (3.2 ± 0.8 l/min vs. 1.0 ± 0.8 l/min vs. 0.7 ± 0.6 l/min; P < 0.001) and dead space ventilation (2.9 ± 1.0 l/min vs. 1.5 ± 0.7 l/min vs. 1.7 ± 0.8 l/min; P < 0.001). Although resulting in different PEEP levels, minimal tidal recruitment and maximal oxygenation PEEP, both following a recruitment maneuver, had similar effects on regional ventilation/perfusion matching.

CONCLUSIONS

When compared to table PEEP without a recruitment maneuver, both minimal tidal recruitment PEEP and maximal oxygenation PEEP following a recruitment maneuver decreased shunting and dead space ventilation, and the effects of minimal tidal recruitment PEEP and maximal oxygenation PEEP were comparable.

摘要

背景

在急性呼吸衰竭中，腹腔内压升高会加重肺塌陷、潮气量募集和通气不均匀。低水平呼气末正压（PEEP）可能会促进肺塌陷和肺内分流，而高水平 PEEP 可能会通过吸气过度扩张增加死腔通气。作者假设，与基于表格的低 PEEP/无募集和基于氧合的高 PEEP/全募集策略相比，一种基于电阻抗断层成像的 PEEP 方法，最大限度地减少潮气量募集，可改善区域通气和灌注匹配，在合并肺损伤和腹腔内压升高的模型中。

方法

在油酸诱导的肺损伤的 15 头猪中，通过腹腔内盐水输注增加腹腔内压。PEEP 以随机顺序设置：（1）基于 PEEP/吸入氧分数表，不进行募集操作；（2）在募集操作后通过电阻抗断层成像指导下最小化潮气量募集；（3）在募集操作后最大化氧合。单光子发射计算机断层扫描用于分析区域通气、灌注和通气。主要观察指标为 PEEP 水平和区域通气/灌注匹配的差异。

结果

（1）表格 PEEP：11 ± 3 cm H2O；（2）最小潮气量募集 PEEP：22 ± 3 cm H2O；（3）最大氧合 PEEP：25 ± 4 cm H2O；P < 0.001。表 PEEP 无募集操作导致最高肺塌陷（28 ± 11%比 5 ± 5%比 4 ± 4%；P < 0.001）、分流灌注（3.2 ± 0.8 l/min 比 1.0 ± 0.8 l/min 比 0.7 ± 0.6 l/min；P < 0.001）和死腔通气（2.9 ± 1.0 l/min 比 1.5 ± 0.7 l/min 比 1.7 ± 0.8 l/min；P < 0.001）。虽然导致了不同的 PEEP 水平，但在募集操作后，最小潮气量募集和最大氧合 PEEP 对区域通气/灌注匹配都有类似的影响。