■ ↑ HCO₃⁻ by bicarbonate buffer system

■ ↓ H⁺ by kidneys (can take several days).

Causes (Any Cause of Hypoventilation)

Symptoms and Signs

A history of the underlying disorder may be evident such as trauma or drug ingestion. The symptoms of respiratory acidosis can range from anxiety, disorientation, confusion, or lethargy to somnolence. On examination, tachycardia and a bounding arterial pulse can occur with carbon dioxide retention. In severe disease, cyanosis and hypotension can result. Papilloedema may be a feature of underlying raised intracranial pressure. Features of a flail chest or any severe chest wall deformity may be evident.

Investigations