My wife is woken up with a choking sensation what is the problem?

Reflux?: Complaints like this can be very well related to reflux. When you lie flat, the acid can come up into your throat. This can cause a cough, phlegm, and the feeling that something is stuck in your throat. One should avoid spicy foods, don't eat less than 2 hours before they lie down, sleep on an incline. If it persists one can try otc reflux meds and see their md.

Probably reflux: Probably stomach juice coming up into her throat leading to irritation of the muscle that encircles the upper part of her food tube (esophagus). When this muscle is irritated it spasms and leads to the feeling of a lump. If stomach juice gets to the voice box it causes severe spasm and the feeling of choking. She should not eat or drink for 3 hours before laying down and sleep elevated.