Which local anesthetic could cause a sustained oxygen desaturation when used for awake fiberoptic intubation?

Benzocaine, often marketed as Hurricaine, is associated with the risk of causing methemoglobinemia, a condition where hemoglobin is unable to effectively carry oxygen, leading to sustained oxygen desaturation. This is particularly important in the context of awake fiberoptic intubation, where maintaining adequate oxygenation is critical.

When benzocaine is applied topically, it has the potential to be absorbed systemically and can lead to the oxidation of hemoglobin to methemoglobin. Methemoglobinemia can produce symptoms such as cyanosis and hypoxia, which would be detrimental during the intubation process. Monitoring oxygen saturation is essential, and if significant levels of methemoglobin are formed, it could result in substantial decreases in the effective oxygen capacity of the blood, thus causing desaturation.

The use of bupivacaine, cocaine, or lidocaine does not typically result in the same kind of adverse oxygenation effects as benzocaine does. These anesthetics are generally safer in terms of maintaining oxygen saturation when used in procedures like awake fiberoptic intubation and do not share the same risk of methemoglobinemia associated with benzocaine. Therefore, benzocaine is clearly the anesthetic with the potential to induce