Acute Respiratory Failure.

Respiratory failure is one of the most common reasons for hospitalization and intensive care unit (ICU) admissions, and a diverse range of etiologies can precipitate it. Respiratory failure can result from various mechanisms such as hypoventilation, diffusion impairment, shunting, ventilation-perfusion mismatch, or a combination of those mentioned earlier. Hence, an accurate understanding of different pathophysiologic mechanisms is required for appropriate patient care. Prompt identification and treatment of various respiratory emergencies such as tension pneumothorax, massive hemoptysis, and high-risk pulmonary embolism lead to fewer complications, shorter ICU and hospital stay, and improved survival. This review article entails common respiratory failure pathologies encountered in the ICU and addresses their epidemiology, pathophysiology, clinical presentation, and management.