Acute respiratory failure (ARF) is a life-threatening impairment of the lungs' ability to oxygenate blood and excrete carbon dioxide (CO₂). ARF may occur from exacerbation of chronic (eg, chronic obstructive pulmonary disease, asthma) or acute (eg, pneumonia, pulmonary edema) illnesses.
Nurses assessing for signs of ARF should consider both respiratory and neurological manifestations. Altered mental status (eg, confusion, agitation, somnolence) is a common and often overlooked symptom that may occur because of the brain's sensitivity to inadequate oxygenation and alterations in acid-base balance from retained CO₂(Option 4). Additional signs and symptoms may include paresthesias, dyspnea, tachypnea, and hypoxemia.

(Option 1) Clients recovering from recent pneumonectomy (ie, surgical removal of part or all of the lung) often experience considerable pain, which may cause respiratory distress if not adequately controlled. A client with tachypnea and severe pain should be seen promptly but only after addressing potential ARF.

(Option 2) Crackles, absent or diminished breath sounds over the affected lobe, and slightly decreased oxygen saturation are expected findings in pleural effusion, in which fluid collects in the space surrounding the lung.

(Option 3) Low-grade fever may occur following surgery (due to the release of inflammatory cytokines) or from postoperative atelectasis. The client should be encouraged to ambulate and deep-breathe.

Educational objective:
Acute respiratory failure is a life-threatening impairment of lung function that inhibits gas exchange. Common symptoms include altered mental status (eg, confusion, agitation, somnolence), paresthesias, dyspnea, tachypnea, and hypoxemia, all of which should be addressed immediately.