Hypercarbia

An abnormal elevation of arterial carbon dioxide tension (PaCO₂), reflecting impaired alveolar ventilation or increased carbon dioxide production, and predisposing to respiratory acidosis with associated cardiopulmonary and neurological disturbances.

Causes

• Pulmonary causes

  • Chronic obstructive pulmonary disease (COPD)

  • Severe asthma with airflow limitation

  • Cystic fibrosis

  • Pulmonary fibrosis

  • Other lung diseases causing impaired ventilation

• Mechanical and airway obstruction causes

  • Obstructive sleep apnea

  • Obesity hypoventilation syndrome

  • Tracheal tumor

  • Upper airway obstruction

  • Chest wall disorders impairing ventilation

• Neurological and neuromuscular causes

  • Muscular dystrophy

  • Myasthenia gravis

  • Guillain-Barré syndrome

  • Spinal cord injury

  • Stroke

  • Traumatic brain injury

  • Encephalitis

• Medications: Sedatives, opioids

• Environmental causes

  • Poor air circulation

  • Deep-sea diving or increased ambient pressure exposure

  • Rebreathing carbon dioxide-rich air

• Sepsis

• Other causes

  • Depressed central respiratory drive

  • Postoperative hypoventilation

  • Inadequate mechanical ventilation

  • Sleep-related hypoventilation disorders