All the following conditions cause type I respiratory failure EXCEPT-
High-Yield Explanation
Type l respiratory failure occurs when alveolar flooding and impaired ventilation of pa of a lung occur(asthma or pneumonia),resulting in hypoxia and normo/hypocapnia(PaO2 <8 kPa and PaCO2 <50 mmHg).Alveolar flooding may be a consequence of pulmonary edema,pneumonia,or alveolar hemorrhage.Causes of type l respiratory failure include acute asthma,pulmonary edema, pneumonia,lobar collapse,pneumothorax,pulmonary embolus,ARDS,lung fibrosis,COPD,right-to-left shunts. Brainstem lesion leading to impaired CNS drive to breathe can lead to type ll respiratory failure with hypoxia and hypercapnia. Ref:Harrison's medicine-18th edition,page no:2199,2200.