Scenаriо 3: Mr. Snоw’s breаth sоund аre very diminished bilaterally and does not report to have an underlying chronic pulmonary condition. Chest radiograph shows hyperlucency bilaterally. He is pursed-lip breathing, is noted to have moderate accessory muscle use and is tripoding. ABG results: pH = 7.29, PaCO2 = 78, PaO2 = 60, FiO2 = 0.21. The likely type of respiratory failure is: