When I first started my anesthesiology training, I almost always used a reinforced endotracheal tube (ETT) for cases where my patient would be positioned prone for an extended period of time. One can imagine that in this position, even if the head is situated in a “prone pillow”, there’s a higher likelihood of the ETT making contact with the bed or another hard surface resulting in a kink.
Reinforced tubes are better able to resist these occlusions when kinked due to a metal wire coiling embedded within the plastic wall of the ETT. This coiling also adds more flexibility to the tube facilitating fiberoptic and tracheostomy intubations.
So these reinforced tubes seem perfect for prone cases. After all, we can rest easy knowing that the ETT will remain patent for the surgery.
Until they kink.
Reinforced ETTs might be more resilient to kinks, but with enough force, they too will bend. The difference is that reinforced tubes have a memory effect which makes them extremely difficult to rebound back to their original diameter once the compressing force (ie, a patient biting on the ETT) is alleviated. In other words, the reinforced ETT will remain kinked. This makes it unfeasible to adequately ventilate or even utilize a Cook exchange catheter through the occluded lumen. The only option is to extubate and reintubate the patient.
Although reinforced ETTs have clear benefits, be mindful of their drawbacks and always plan for the worst case scenario where the ETT becomes permanently kinked.