Mr Hopper develops signs of acute pulmonary oedema (APO). Investigations include arterial blood gases (ABG) which reveal: pH 7.25 PaO2 68 PaCO2 60. He is ordered oxygen and a diuretic (frusemide). Briefly explain the physiological process that occurs in acute pulmonary oedema and list 6 signs or symptoms. In your answer identify the type of acid/base imbalance Mr Hooper has and explain how oxygen and a diuretic will improve his respiratory and cardiac function