Respiratory Acidosis Clinical Presentation
- Author: Ryland P Byrd Jr, MD; Chief Editor: Zab Mosenifar, MD more...
History and Physical Examination
The clinical manifestations of respiratory acidosis are often those of the underlying disorder. Manifestations vary depending on the severity of the disorder and on the rate of development of hypercapnia. Mild to moderate hypercapnia that develops slowly usually has minimal symptoms.
Patients may be anxious and may complain of dyspnea. Some patients may have disturbed sleep and daytime hypersomnolence. As the partial arterial pressure of carbon dioxide (PaCO2) increases, the anxiety may progress to delirium, and patients become progressively more confused, somnolent, and obtunded. This condition is sometimes referred to as carbon dioxide narcosis.
Physical examination findings in patients with respiratory acidosis are usually nonspecific and are related to the underlying illness or the cause of the respiratory acidosis.
Thoracic examination of patients with obstructive lung disease may demonstrate diffuse wheezing, hyperinflation (ie, barrel chest), decreased breath sounds, hyperresonance on percussion, and prolonged expiration. Rhonchi may also be heard.
Cyanosis may be noted if accompanying hypoxemia is present. Digital clubbing may indicate the presence of a chronic respiratory tract disease or other organ system disorders.
The patient's mental status may be depressed if severe elevations of PaCO2 are present. Patients may have asterixis, myoclonus, and seizures.
Papilledema may be found during the retinal examination. Conjunctival and superficial facial blood vessels may also be dilated.
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