On Twitter recently, I've been highlighting some really bad ideas courtesy of the medical literature. From injecting vaseline into your own penis, to pumping compressed air up your rectum for a joke, people have tried it and they've ended up on PubMed as a result.
But a recent paper details an extreme case. Canadian medics Anny Sauvageau and colleagues report on the life and death of a 35 year old Hispanic man who, we're told,
filmed several of his autoerotic asphyxia sessions. After his accidental hanging death, several films were found at the scene, including 3 filmed nonlethal ligature strangulations.The videos - which before you go and look, are not included as Supplementary Materials - are of scientific interest, because they offer a rare glimpse into what happens during human strangulation.
In these 3 ligature strangulations, the man is sitting on a chair. A pair of pajama pants is rolled once around his neck, with the extremities of the pants falling down on each side of his chest. The man is pulling the extremities of the pants with both hands to apply compression on his neck. After losing consciousness, he ceases to pull on the ligature, and the pants slowly loosen around the neck. A few seconds later, he regains consciousness and gets up from the chair.
You might think that given that people have been strangling each other for thousands of years, it would be a well-understood phenomenon, but in fact it's very difficult to study. Most of the available evidence comes from video recordings of execution by hanging, but there are only perhaps 10 of these records on file. Although there's also been an interesting line of research involving judo, in which judo masters apply choke holds to willing volunteers. These include one remarkable paper in which brain activity was recorded before, during and after.
Anyway, for what it's worth, this is what seems to happen during strangulation, including hanging:
- Loss of consciousness (10 +- 3 seconds).
- Convulsions: (14 +- 3 seconds).
- Decerebrate rigidity: (19 +- 5 seconds)
- Start of very deep respiratory attempt (19 +- 5 seconds)
- Decorticate rigidity (38 +- 15 seconds)
- Loss of muscle tone (1 minute 17 seconds +- 25 seconds)
- End of the very deep respiratory attempt (1 minute 51 seconds +- 30 seconds)
- Last muscle movement (4 minutes 12 seconds +- 2 minutes 29 seconds)
Until the last time he tried it, when he didn't.
Sauvageau A, Ambrosi C, and Kelly S (2012). Three Nonlethal Ligature Strangulations Filmed by an Autoerotic Practitioner: Comparison of Early Agonal Responses in Strangulation by Ligature, Hanging, and Manual Strangulation. The American journal of forensic medicine and pathology PMID: 22922552
6 comments:
In Brazilian Jiu Jitsu (a Judo-derived combat sport with a larger focus on submission holds i.e. joint locks and chokes) this happens fairly often. Though we tap out (submit/cry uncle) before loss of consciousness the vast majority of the time, everyone who has been doing it a few years has been on either end of a couple of choke outs.
Anecdotally there is definitely another mechanism at work than just mechanical compression -> cerebral ischemia. 6-10 seconds is taught as standard for loss of consciousness, but occasionally it happens extremely quickly, one to two seconds, and I've even seen it happen a couple of times after the hold is released. Anyone who wants copious video material of this has only to type 'BJJ sleep' into YouTube and anyone who wants eerily cheerful volunteers for study has only to give their local club a ring.
P.S. A lot of Judo/BJJ chokes [i]are[/i] ligature rather than 'manual' strangulations, the uniform being used as the ligature. That paper is also wrong in its use of Judo terminology, hadaka-jime is just a choke which doesn't use the uniform, it exists in versions that target the blood vessels and/or the windpipe.
How is the ethnicity of the case study patient relevant?
How is the ethnicity of the case study patient relevant?
2 September 2012 02:54
To be consistant you should complain also about the sex of the subjet of the post being known, shouldn't you?
To be politically correct that is.
On the other hand, in forensic and in medical research in general -and even in science in general-you need as much precision as you can get on the subject of your study.
Good journalism -real journalism- cannot be politically correct either.
There are a number of nerves running down the side of the neck, a sharp blow delivered here, (or a choke hold applied suddenly and with enough force), could conceivably leave an individual unconscious.
The mechanism of death in judicial hanging is asphyxiation but the long drop followed by the neck being broken is thought to render the condemned man (or woman) unconscious almost immediately possibly for the same reason.
Most cases of autoerotic asphyxiation that I have encountered have been done by placing a plastic bag over the head. Potentially even more dangerous as if the individual does lose consciousness they are unlikely to remove the bag and revive. I wonder if the individual would experience convulsions.
I don't think I will be putting it to the test
Decerebrate comes before decorticate? Confused.
That is weird come to thing about it. But that's the order in the paper.
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