Positive end expiratory pressure (PEEP) may prevent cyclic opening and collapsing alveoli in acute respiratory distress syndrome (ARDS) patients. but it may play a role also in general anesthesia. This review is organized in two sections. The first one reports the pathophysiological effect of PEEP on thoracic pressure and hemodynamic and cerebral perfusion pressure. https://www.parisnaturalfoodes.shop/product-category/cal-mag-plus/