Each group was sub-divided into three parts:high peak inspiratory pressure group (HPIP),moderate peak inspiratory pressure group (MPIP)and low peak inspiratory pressure group (LPIP).

• 每组又分为高吸气峰压(HPIP)、中吸气峰压(MPIP)和低吸气峰压(LPIP)共6组进行机械通气。