22.12c Effects of Obesity & Predicting Difficulty: An Imperfect Science

The airway effects of obesity are complex but negative overall.

Much of the anatomic problem with intubation in persons who are morbidly obese can be overcome with proper positioning—that is, the ramped position, which was described earlier in the chapter.

Obesity limits the effects of preoxygenation due to reduced functional residual capacity and increased oxygen demand so that time to perform the intubation before critical hypoxemia occurs can be limited.

Obesity definitely makes BVM ventilation more difficult, and some extraglottic rescue devices cannot generate enough airway pressure to lift a very heavy chest.

Finally, obesity can make identification of landmarks for a surgical airway very difficult.

Predicting difficult intubation is an imperfect science.

Most of the methods commonly used in hospitals are not useful outside them.

Fortunately, specific prehospital criteria have been developed for prehospital use.

Do not, however, let the absence of any predicted difficulties create a sense of complacency.

All patients, no matter how favorable their airway appears, can prove difficult or impossible to intubate.

If you have not encountered such a patient, you have not yet intubated enough! You should assume that all patients will have a difficult airway and prepare for the worst every time.