Chapter 24 - Airway Management in Obesity

Summary

Obesity is a risk factor for increased difficulty in most modalities of airway management. It decreases ease and effectiveness of face mask ventilation, supraglottic airway device use and front of neck airway techniques and probably makes laryngoscopy more difficult. When difficulty occurs, airway rescue techniques are more likely to fail in the obese patient. Obesity also increases the risk of aspiration and difficulty in lung ventilation, both of which may necessitate changes in anaesthetic technique. Most importantly, obesity reduces the time available for airway management before hypoxia supervenes. To worsen matters, obesity reduces the efficacy of pre-oxygenation and safe apnoea time is less prolonged with apnoeic oxygenation techniques than in the non-obese population. To compound these factors obesity is associated with obesity-specific (e.g. obstructive sleep apnoea, obesity hypoventilation syndrome) and non-specific co-morbidities (diabetes, asthma, hypertension). With increasing numbers of obese patients and increasing degrees of obesity in the surgical population it is essential that all anaesthetists are familiar with the potential complications of airway management in the obese and the techniques that may mitigate or manage risk.