Department of Anesthesiology and Intensive Care Medicine, University of Bonn, Bonn, Germany.
J Neurosurg Anesthesiol. 2010 Oct;22(4):323-9. doi: 10.1097/ANA.0b013e3181e775f1.
Systemic-blood flow, cerebral-blood flow, and spinal cord blood flow can be affected by mechanical ventilation. We investigated the effect of spontaneous breathing on cerebral and spinal blood flow during airway pressure release ventilation (APRV) with and without spontaneous breathing.
Twelve pigs with oleic-acid-induced lung injury were ventilated with APRV with or without spontaneous breathing in random order. Without spontaneous breathing, either the upper airway pressure limit of mechanical ventilation or the ventilator rate was increased to maintain pH and PaCO2 constant. Systemic hemodynamic parameters were determined by the double indicator dilution method, cerebral and spinal cord blood flow was measured with colored microspheres.
ANOVA+Newmann-Keuls-test.
As compared with APRV without spontaneous breathing and high tidal volume (V(T)) spontaneous breathing during APRV showed higher systemic blood flow and perfusion of the basal ganglia, frontal lobe, hippocampus, brain stem, temporal lobe, thalamus (all P<0.001), cerebellum, spinal cord (all P<0.01), and the central cortical region (P<0.05). During APRV without spontaneous breathing and low V(T) blood flow was lower in the basal ganglia, frontal lobe, hippocampus (all P<0.01), and temporal lobe (P<0.05) whereas perfusion of the thalamus, central cortical region, brain stem, cerebellum, and spinal cord were not different compared with APRV with spontaneous breathing.
In parallel with higher systemic blood flow regional cerebral and spinal cord blood flow were also higher when spontaneous breathing was maintained during APRV. The higher regional blood flow by maintaining spontaneous breathing was more pronounced when compared with full ventilatory support using high V(T).
全身血流、脑血流和脊髓血流都会受到机械通气的影响。我们研究了在有和没有自主呼吸的情况下，气道压力释放通气（APRV）中自主呼吸对脑和脊髓血流的影响。
12 只油酸诱导肺损伤的猪随机接受有和没有自主呼吸的 APRV 通气。在没有自主呼吸的情况下，要么增加机械通气的上气道压力限制，要么增加呼吸机频率，以保持 pH 值和 PaCO2 不变。通过双指示剂稀释法测定全身血流动力学参数，用彩色微球测量脑和脊髓血流。
方差分析+Newmann-Keuls 检验。
与 APRV 无自主呼吸和高潮气量（V(T)）自主呼吸相比，APRV 期间的自主呼吸显示出更高的全身血流和基底节、额叶、海马、脑干、颞叶、丘脑（均 P<0.001）、小脑、脊髓（均 P<0.01）和中央皮质区（P<0.05）的灌注。在 APRV 无自主呼吸和低 V(T)的情况下，基底节、额叶和海马（均 P<0.01）以及颞叶（P<0.05）的血流较低，而丘脑、中央皮质区、脑干、小脑和脊髓的灌注与 APRV 自主呼吸时无差异。
在自主呼吸维持期间，APRV 时全身血流增加，与全身血流增加平行，区域性脑和脊髓血流也增加。与使用高 V(T)的充分通气支持相比，通过维持自主呼吸来增加区域性血流更为明显。
