Manual hyperinflation technique (MHI) is provided for use in patients with lung atelectasis. Several studies demonstrated the short-term effects of increased oxygenation and pulmonary compliance, improved lung collapse, and removed pulmonary secretions. To apply MHI technique, patients were disconnected from the ventilator which lead to the adverse effect of losing positive end expiratory pressure (PEEP) corresponding to loss of functional residual capacity, decreased oxygenation, and shear stress of distal lung units.