What is a common sign of respiratory failure?

Cyanosis is a common sign of respiratory failure, commonly indicating that there is inadequate oxygenation in the blood. When a patient's oxygen levels drop significantly, the skin and mucous membranes can take on a bluish tint due to the increased levels of deoxygenated hemoglobin. This can clearly signal to clinicians that the patient is experiencing severe respiratory distress or systemic hypoxia.

Increased heart rate may occur in response to various stimuli, including respiratory failure, but it is more of a general response to stress or hypoxia rather than a specific sign of respiratory failure. Altered mental status can also be indicative of respiratory failure as the decreased oxygen supply to the brain can lead to confusion, drowsiness, or other cognitive impairments. Unilateral chest expansion is not typically associated with respiratory failure; instead, it might indicate localized conditions such as a pneumothorax or pleural effusion. Understanding these signs helps medical providers assess patients experiencing difficulties with their respiratory function.