critical care medicine
Ventilatory Failure
Introduction
Ventilatory failure is a rise in PaCO2 (hypercapnia) that occurs when the respiratory load can no longer be supported by the strength or activity of the system. The most common causes are severe acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD), overdoses of drugs that suppress ventilatory drive, and conditions that cause respiratory muscle weakness (eg, Guillain-Barré syndrome, myasthenia gravis, botulism). Findings include dyspnea, tachypnea, and confusion. Death can result. Diagnosis is by arterial blood gas measurement and patient observation; chest x-ray and clinical evaluation may help delineate cause. Treatment varies by condition but often includes mechanical ventilation. (See also Overview of Mechanical Ventilation .) The 2 most common causes of ventilatory failure are Severe acute exacerbation of asthma (ie, status asthmaticus) Exacerbation of COPD (chronic obstructive pulmonary disease) Respiratory failure due to COPD is termed acute-on-chronic respiratory failure (ACRF). 