Having been the recipient of a variety of chokes, it seems to have gone something like this:
Airway choke: very uncomfortable since windpipe is squished. Can cause damage to the larynx and hyoid bone. The choke usually involves pressing a forearm across the throat, but anything else will do (escrima stick, broom handle, and so on). The BTK killer tried to use his hands for such a choke, but quickly discovered that hands are the weakest way to do this save when employed by the terrifically strong or grossly outsized. Recipients conk out via asphyxiation. The technique doesn't seem to work quite as well as blood chokes, more often causing submission for the discomfort involved than for impending unconsciousness. In fact, Gunji Koizumi (the “Father of British Judo”), wrote in “My Study of Judo: The Principles and the Technical Fundamentals,” that airway chokes take a few minutes to work and cause much discomfort, whereas blood chokes, when applied correctly, take effect within a few seconds.
Blood choke: compressing carotid(s) in the neck to shut off blood flow to brain. Not that uncomfortable, in general. Just feels like a squeezing on the neck. A good choke of this sort works in about 8 to 14 seconds. Recipients regain consciousness in about 10 to 20 seconds and are usually unaware of what has just happened.
Blood and air choke: these employ the uncomfortable elements of the airway choke and the greater effectiveness of the blood choke. One of these, in particular, (a technique from Silat, as I recall), made my head feel like a water-balloon squeezed to the point of exploding. That went for the inside of my skull as well as the arteries and veins throughout, as if I suddenly felt lots of things in there I'd never felt before, and they were all about to pop.
Additional notes on feeling and what happens to body:
- Pressure on the larynx and trachea produce excruciating pain in airway chokes.
- No similar level of pain associated with other (blood choke) techniques.
- Unconsciousness may result from restricted air flow, blood flow, or both.
- Face will redden (or purple) due to disturbance in pressure in carotid arteries and jugular veins.
- Convulsions may occur, similar to a short epileptic seizure.
- Heart rate will increase, blood pressure will increase, pupils will dilate due to stimulation of the sympathetic nervous system (vagus nerve). (Or carotid sinux reflex.)
- Upon being rendered unconscious, recipient of choke is limp like a rag doll.
- Holding a choke too long after recipient is unconscious can be fatal.