Medically Correct Writing

Knock-Out, Part 1: Jab in the Neck

This seems to become quite the popular thing on the screen and in several books. The problem is, it's often very badly done, and not really that practical in real life.

First, basic anatomy. There are only four major veins and two major arteries that can be reached in the neck. On top of that, in an upright position, all of those veins will be collapsed, nearly impossible to stick a needle in. Have a look at the cross section of the neck I added to this chapter. The red circles are arteries, the blue are veins (arteries carry blood away from the heart and they pulse, veins carry blood back to the heart and they don't pulse). The big red one in the middle is the oesophagus, by the way, not an artery. Can you imagine how hard it would be to stick into those tiny circles, but not through? Not to mention, to avoid damage to any other structures, like the mass of nerves, or the airways.

Second, the way they tend to hold their syringe, in a fist, with their thumb on the plunger. That's how you hold an epinephrine pen, with a really short needle, that needs to be jammed in the fat just below your skin, in your buttocks where it can't really harm that much. You do not hold a syringe with a needle as long as your finger like that. As said above, you'll damage things. You can't aim, and you have no idea whether you're too deep or not. (And if you have small hands like mine, you'll have trouble reaching the plunger with your thumb).

Third, the location where they plunge the needle. Often, you'll find them sticking it too far to the back, not anywhere near any blood vessels. Your sedative will end up, if you're lucky, somewhere in your muscle tissue. If you're not, in nerves.

Now, you may think: does it matter that much? We just want to knock them out, so it doesn't really matter if I miss the exact location, right?

Well, yes, it matters. You see, injecting sedatives in vessels, though rarely done with a syringe and needle directly (you'll use an IV or a central line in the hospital), makes your medication work the fastest. It will still take a few seconds, but if you've done it well, it'll work fast. If you miss your vein or artery, which is almost inevitable in this situation, your medication will work much, much slower, if at all. And in TV series, the unsuspecting victims tend to drop to the ground after about a second.

Lastly, there's the issue of the medication itself. Be careful if you name your medication and dose. Some have distinctive colours, like propofol, a common anaesthetic, is milky white and not transparent. If you name a dose, it might not be enough to knock a person out, or it might be too much and kill them.

If you really wanted to knock someone out with this method, you'd have to place them on an examination table, tilt the head down so the veins dilate (more blood staying in the head), carefully inject a needle at the right angle (45° or less), and inject the right dose of the right medication.

I suspect if your character is a trained killer, they might know how to pull this off in standing position, fast and the right medication, but it might still go wrong. The right dose to knock someone out is different for everyone and needs to be calculated carefully, depending on things such as weight and gender.

To be fair, though, if you can pull this off, this might be the least damaging way of knocking someone out, compared to the other options that are popular on TV.

There we go. We've finally moved on from resuscitation, onto knocking people out. More next week!