自六十年代后期起,使用呼气终末正压(POsitive End Expiratory Pressure简称PEEP),纠正呼吸窘迫综合征或其他原因换气弥散障碍导致的低氧血症和病理性肺分流已取得肯定效果。然而,由于气道内的连续正压可造成一系列循环呼吸并发症(如肺泡破裂、右心衰竭、大静脉回流受阻等),使不少临床家使用时存在顾虑。一般构成PEEP的工具多为机械通气机及其呼气活瓣。 Since the late 1960s, positive results have been achieved with the use of PEEP to correct hypoxemia and pathologic pulmonary shunts resulting from respiratory distress syndrome or other causes of diffuse ventilatory disorders . However, due to the continuous positive pressure within the airway can cause a series of circulatory complications (such as alveolar rupture, right heart failure, venous obstruction, etc.), so many clinicians have concerns. PEEP tools are generally composed of mechanical ventilator and expiratory valve.