Mentzelopoulos Spyros D, Zakynthinos Spyros G, Roussos Charris, Tzoufi Maria J, Michalopoulos Argyris S
Department of Intensive Care Medicine, Henry Dunant General Hospital; and Evangelismos General Hospital, Athens, Greece.
Anesth Analg. 2003 Jun;96(6):1756-1767. doi: 10.1213/01.ANE.0000064282.79068.1E.
Pronation might favorably affect respiratory system (rs) mechanics and function in volume-controlled, mode-ventilated chronic obstructive pulmonary disease (COPD) patients. We studied 10 COPD patients, initially positioned supine (baseline supine [supine(BAS)]) and then randomly and consecutively changed to protocol supine (supine(PROT)), semirecumbent, and prone positions. Rs mechanics and inspiratory work (W(I)) were assessed at baseline (0.6 L) (all postures) and sigh (1.2 L) (supine(BAS) excluded) tidal volume (V(T)) with rapid airway occlusion during constant-flow inflation. Hemodynamics and gas exchange were assessed in all postures. There were no complications. Prone positioning resulted in (a) increased dynamic-static chest wall (cw) elastance (at both V(Ts)) and improved oxygenation versus supine(BAS), supine(PROT), and semirecumbent, (b) decreased additional lung (L) resistance-elastance versus supine(PROT) and semirecumbent at sigh V(T), (c) decreased L-static elastance (at both V(Ts)) and improved CO(2) elimination versus supine(BAS) and supine(PROT), and (d) improved oxygenation versus all other postures. Semirecumbent positioning increased mainly additional cw-resistance versus supine(BAS) and supine(PROT) at baseline. V(T) W(I)-sub-component changes were consistent with changes in rs, cw, and L mechanical properties. Total rs-W(I) and hemodynamics were unaffected by posture change. After pronation, five patients were repositioned supine (supine(POSTPRO)). In supine(POSTPRO), static rs-L elastance were lower, and oxygenation was still improved versus supine(BAS). Pronation of mechanically ventilated COPD patients exhibits applicability and effectiveness and improves oxygenation and sigh-L mechanics versus semirecumbent ("gold standard") positioning.
By assessing respiratory mechanics, inspiratory work, hemodynamics, and gas exchange, we showed that prone positioning of mechanically ventilated chronic obstructed pulmonary disease patients improves oxygenation and lung mechanics during sigh versus semirecumbent positioning. Furthermore, certain pronation-related benefits versus preprone-supine positioning (reduced lung elastance and improved oxygenation) are maintained in the postprone supine position.
在容积控制、模式通气的慢性阻塞性肺疾病（COPD）患者中，俯卧位可能对呼吸系统（rs）力学和功能产生有利影响。我们研究了10例COPD患者，最初取仰卧位（基线仰卧位[仰卧位（BAS）]），然后随机连续更换为方案仰卧位（仰卧位（PROT））、半卧位和俯卧位。在基线（0.6L）（所有体位）和叹息（1.2L）（排除仰卧位（BAS））潮气量（V(T)）时，通过恒定流量充气期间的快速气道阻塞评估rs力学和吸气功（W(I)）。在所有体位下评估血流动力学和气体交换。未出现并发症。与仰卧位（BAS）、仰卧位（PROT）和半卧位相比，俯卧位导致（a）动态-静态胸壁（cw）弹性增加（在两个V(T)时）且氧合改善，（b）在叹息V(T)时，与仰卧位（PROT）和半卧位相比，额外肺（L）阻力-弹性降低，（c）与仰卧位（BAS）和仰卧位（PROT）相比，L静态弹性降低（在两个V(T)时）且CO(2)清除改善，以及（d）与所有其他体位相比，氧合改善。半卧位主要在基线时与仰卧位（BAS）和仰卧位（PROT）相比增加额外的cw阻力。V(T) W(I)子成分变化与rs、cw和L力学特性变化一致。rs总W(I)和血流动力学不受体位变化影响。俯卧位后，5例患者重新取仰卧位（仰卧位（POSTPRO））。在仰卧位（POSTPRO）中，静态rs-L弹性较低，且与仰卧位（BAS）相比氧合仍得到改善。机械通气的COPD患者俯卧位显示出适用性和有效性，与半卧位（“金标准”）体位相比改善了氧合和叹息-L力学。
通过评估呼吸力学、吸气功、血流动力学和气体交换，我们表明机械通气的慢性阻塞性肺疾病患者俯卧位与半卧位相比在叹息时改善了氧合和肺力学。此外，与俯卧前仰卧位相比，俯卧位的某些益处（降低肺弹性和改善氧合）在俯卧后仰卧位中得以维持。
