The respiratory system is crucial for oxygenation and carbon dioxide elimination. Chest X-rays are used to assess physical signs and radiological appearances of respiratory disease, including consolidation, pleural effusion, and lung collapse. Key features include mediastinal shift, diaphragm obscuration, and changes in lung density. Normal pulmonary volumes are evaluated by assessing lung field density, mediastinal position, diaphragm clarity, and horizontal fissure position. Regional lung parenchyma evaluation, diaphragm and pleura, heart and mediastinum, upper abdomen, bone, and soft tissues are also assessed. Special checks include apical regions for pneumothorax, tuberculosis, and tumors. Hypoxia is inadequate oxygenation, classified by factors affecting tissue oxygen delivery. Respiratory failure is categorized into types based on underlying pathophysiology, including hypoxemic (AHRF), ventilatory, and mixed types. Management involves oxygen therapy, noninvasive monitoring (pulse oximetry, capnography), and mechanical ventilation for severe cases. Ventilation modes include volume-controlled, pressure-controlled, and pressure support. Complications of ventilatory support include hemodynamic instability, acid-base disturbances, and respiratory muscle atrophy. Respiratory failure management varies by type, with AHRF requiring high FiO2 and PEEP, while ventilatory failure involves hypercapnia. Liberation from mechanical ventilation is guided by oxygenation, respiratory mechanics, and clinical assessment. Complications include ventilator-induced lung injury, barotrauma, and nosocomial pneumonia. Management of specific conditions like acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), community-acquired pneumonia, healthcare-associated pneumonia, and pulmonary tuberculosis involves targeted therapies, antibiotic regimens, and supportive care. Aspiration syndromes, fat embolism, and other conditions require immediate intervention to prevent respiratory failure and systemic complications.The respiratory system is crucial for oxygenation and carbon dioxide elimination. Chest X-rays are used to assess physical signs and radiological appearances of respiratory disease, including consolidation, pleural effusion, and lung collapse. Key features include mediastinal shift, diaphragm obscuration, and changes in lung density. Normal pulmonary volumes are evaluated by assessing lung field density, mediastinal position, diaphragm clarity, and horizontal fissure position. Regional lung parenchyma evaluation, diaphragm and pleura, heart and mediastinum, upper abdomen, bone, and soft tissues are also assessed. Special checks include apical regions for pneumothorax, tuberculosis, and tumors. Hypoxia is inadequate oxygenation, classified by factors affecting tissue oxygen delivery. Respiratory failure is categorized into types based on underlying pathophysiology, including hypoxemic (AHRF), ventilatory, and mixed types. Management involves oxygen therapy, noninvasive monitoring (pulse oximetry, capnography), and mechanical ventilation for severe cases. Ventilation modes include volume-controlled, pressure-controlled, and pressure support. Complications of ventilatory support include hemodynamic instability, acid-base disturbances, and respiratory muscle atrophy. Respiratory failure management varies by type, with AHRF requiring high FiO2 and PEEP, while ventilatory failure involves hypercapnia. Liberation from mechanical ventilation is guided by oxygenation, respiratory mechanics, and clinical assessment. Complications include ventilator-induced lung injury, barotrauma, and nosocomial pneumonia. Management of specific conditions like acute lung injury (ALI)/acute respiratory distress syndrome (ARDS), community-acquired pneumonia, healthcare-associated pneumonia, and pulmonary tuberculosis involves targeted therapies, antibiotic regimens, and supportive care. Aspiration syndromes, fat embolism, and other conditions require immediate intervention to prevent respiratory failure and systemic complications.