| Airway disorders Asthma Acute exacerbation of chronic bronchitis or emphysema Obstruction of pharynx, larynx, trachea, mainstem bronchus, or lobar bronchus by edema, mucus, mass, or foreign body Pulmonary edema Increased hydrostatic pressure Left ventricular dysfunction (eg, myocardial ischemia, heart failure) Mitral regurgitation Left atrial outflow obstruction (eg, mitral stenosis) Volume overload states Increased pulmonary capillary permeability Acute respiratory distress syndrome Acute lung injury Unclear etiology Neurogenic Negative pressure (inspiratory airway obstruction) Re-expansion Tocolytic-associated Parenchymal lung disorders Pneumonia Interstitial lung diseases Diffuse alveolar hemorrhage syndromes Aspiration Lung contusion Pulmonary vascular disorders Thromboembolism Air embolism Amniotic fluid embolism Chest wall, diaphragm, and pleural disorders Rib fracture Flail chest Pneumothorax Pleural effusion Massive ascites Abdominal distention and abdominal compartment syndrome | Neuromuscular and related disorders Primary neuromuscular diseases Guillain-Barré syndrome Myasthenia gravis Poliomyelitis Polymyositis Drug- or toxin-induced Botulism Organophosphates Neuromuscular blocking agents Aminoglycosides Spinal cord injury Phrenic nerve injury or dysfunction Electrolyte disturbances Hypokalemia Hypophosphatemia Myxedema Central nervous system disorders Drugs: sedatives, hypnotics, opioids, anesthetics Brainstem respiratory center disorders: trauma, tumor, vascular disorders, hypothyroidism Intracranial hypertension Central nervous system infections Increased CO2 production Fever Infection Hyperalimentation with excess caloric and carbohydrate intake Hyperthyroidism Seizures Rigors Drugs |