Abstract
Obesity is an increasingly prevalent disease and is a root and complication of conditions necessitating mechanical ventilation. Obese patients require a careful approach due to the particular manner of how ventilatory mechanics is affected, if obstructive sleep apnea (OSA) is present. The two main diagnoses we may encounter while ventilating these patients are obesity hypoventilation syndrome (OHS) and chronic obstructive pulmonary disease (COPD) in an obese patient, which has been recently proposed as a novel phenotype of COPD. The excessive amount of fat in the abdomen, chest wall, and around upper airways warrants the use of special ventilation modes and settings. This chapter provides insight into which issues should be considered when ventilating an obese patient, either in acute or chronic conditions. We stress the importance of acknowledging the high risk of OSA and how OSA affects the ventilation algorithms.