Respiratory Failure

Respiratory failure is a state of inadequate gas exchange by the respiratory system, in which arterial oxygen, carbon dioxide, or both cannot be kept at normal levels; a drop in blood oxygen is called hypoxemia and a rise in carbon dioxide is called hypercapnia. It is classified as Type 1 or Type 2 depending on which gas is abnormal, and as acute or chronic depending on how quickly it develops, with clinical definitions generally requiring an increased respiratory rate, abnormal blood gas measurements, and visible signs of increased breathing effort. It can be caused by a wide range of underlying conditions, including stroke, cystic fibrosis, chronic obstructive pulmonary disease, acute respiratory distress syndrome, pneumonia, pulmonary embolism, and neuromuscular diseases such as amyotrophic lateral sclerosis, and it produces shortness of breath, bluish skin discoloration, rapid heart rate, rapid breathing, headache, and in severe cases seizures, fainting, or coma. Diagnosis relies on arterial blood gas testing, and treatment addresses the underlying cause while supporting breathing with oxygen therapy or mechanical ventilation as needed. It occurs at a rate of roughly ten to eighty cases per hundred thousand people, and about a third of hospitalized cases of acute respiratory failure are fatal.