comfort + pain

We just had a class on how to give injections. I had always been under the impression that giving injections was pretty much like playing darts: stand back, loosen up the wrist, let fly, and if it bounces off the target you lose your turn.

But it turns out it's more complex than that. You have to use different types of needles and different techniques depending on whether you want to inject into the skin, the fat or the muscle, which in turn depends on what kind of stuff you're injecting and how much of it.

We were injecting water into little latex and sponge models rather than on ourselves or each other, although one of my Esteemed Colleagues did manage to stab himself in the thumb.

When you're doing an intramuscular injection the needle is bigger, longer, and you plunge straight in rather than mincing around at an angle like you might for an intradermal injection. Apparently you also have to inject the fluid pretty slowly because it is "more comfortable" for the patient. I was struck by this phrase because I think what it really means is "less painful" for the patient. I can't imagine too many people getting honking big injections and saying, "Mmm, that was pleasingly comfortable".

I suppose that if you conceive of the world in terms of dynamic opposition of absolutes then "more comfortable" is the same thing as "less painful" - they are both talking about moving away from the "agony" end of the line. But "less painful" has a bit of the same quality as "I've stopped beating my wife". It is objectively better but still not much chop.

I wonder which phrase is better for the patient? If I tell you that some treatment will make you more comfortable, will you value that treatment more or less than if I told you it would reduce your pain? Someone must have done some research on this. I know that economists and psychologist have looked at the question of how people respond to potential rewards or losses and have found that people respond very differently depending on the way it is described to them. People seem to prefer certainty of outcome when considering losses but prefer the magnitude of the benefit when considering rewards. This is why lotteries are so popular.

Something similar should hold for medical treatment and the choices that patients make. It's very possible that doctors are unwittingly influencing their patients' decision by the frame of reference they use.

If only someone would set up a hugely unethical study to discover the truth!