Nielsen L S, Kirkegaard L
Aalborg Sygehus, anaestesiafdelingen.
Ugeskr Laeger. 1998 Aug 3;160(32):4649-50.
Animal experiments and human studies have shown better oxygenation in mechanically ventilated patients with ARDS when the patient is situated in the prone position. In contradiction to former theories of a gravitational gradient of lung perfusion, a number of investigators have found that lung perfusion is preferentially distributed to the dorsal lung regions regardless of body position. The basal atelectasis and oedema in ARDS are resolved and only partly distributed anteriorly in the prone position, and these areas are thereby better ventilated. The combination of better ventilation and unchanged perfusion improves the ventilation/perfusion ratio and decreases the shunt in the prone position. In two cases of prone position in mechanically ventilated patients the PaO2/FiO2 ratio increased from 7.5 to 14.3 and from 8.8 to 19.8 after one hour in the prone position, and some of the improvement was permanent. Prone position has only minor side effects and is recommended as the first choice amongst adjunct therapies in mechanical ventilation in patients with ARDS remaining hypoxic in conventional therapy in the supine position.
动物实验和人体研究表明，患有急性呼吸窘迫综合征（ARDS）的机械通气患者处于俯卧位时，氧合情况更佳。与以往关于肺灌注重力梯度的理论相反，许多研究人员发现，无论身体处于何种姿势，肺灌注都优先分布于肺的背侧区域。ARDS中的基底肺不张和水肿在俯卧位时得到缓解，且仅部分分布于前部，因此这些区域能得到更好的通气。通气改善且灌注不变的联合作用提高了通气/灌注比，并降低了俯卧位时的分流。在两例机械通气患者采用俯卧位的情况中，俯卧位一小时后，动脉血氧分压/吸入氧分数值（PaO2/FiO2）比值分别从7.5升至14.3，以及从8.8升至19.8，且部分改善是永久性的。俯卧位仅有轻微副作用，在传统仰卧位治疗中仍存在低氧血症的ARDS患者进行机械通气时，俯卧位被推荐作为辅助治疗的首选方法。
