(Fig. 41-5: Complicating anatomic factors in infants)

1. The majority of neonates are preferential nose breathers, and anything that obstructs the nares may compromise the neonate's ability to breathe.
2. The large tongue occupies relatively more space in the infant's oropharynx, promoting both soft tissue obstruction of the upper airway and increasing the difficulty of laryngoscopic examination and intubation of the infant's trachea.
3. In adults, the narrowest aspect of the upper airway is at the vocal cords, but in neonates, there is further narrowing until the level of the cricoid ring.
   1. Because this narrowing is susceptible to trauma from intubation or placement of too large an endotracheal tube, uncuffed tubes have traditionally been use in the neonatal period.
   2. Cuffed, small-volume, high-resistance endotracheal tubes provide an adequate airway with marginal changes to the diameter of the airway. (Most practitioners now use a cuffed tube in neonates and young infants.)

Neonatal Anesthesia

1. Physiology of the Infant and the Transition Period
2. Anatomy of the Neonatal Airway
3. Anesthetic Drugs in Neonates
4. Anesthetic Management of the Neonate
5. Special Considerations
6. Surgical Procedures in Neonates