Notes on
harness hang syndrome

The following is quoted, by permission, from the Adult Rope Arts list on Yahoo:

Google "suspension bondage" today, and the fourth entry you'll find is a Widipedia file which provides a link to: "the newly recognized Harness Hang Syndrome," that is listed along with nerve compression, as one of major risks of suspension bondage. Interestingly, and unfortunately, the link doesn't lead anywhere.

Google around some more, and you'll come upon Paul Seddon's 2002 report to the UK Health And Safety Initiative, which details and builds on the admittedly sparse amount of information on the syndrome. Here is the link. It's 104 pdf pages long, however, so here's a recap of what I think is essential to know.

The syndrome has several names, Suspension Trauma, Harness Induced Pathology, and HHS. Between 1964 and 1972 thirteen cavers had died mysteriously while suspended on rappel. Each time the reason for death was attributed to hypothermic exhaustion, but a 1983 study of these deaths led France's medical commission to consider the possibility of an additional factor potentially responsible for the cause of death: motionless suspension in a sit-harness. Medical problems arising from being upright and motionless are well understood. We've all felt dizzy standing up to fast from a supine position, and I've witnessed more than a few guys face plant after being at attention on parade for a long time back when I was in the military. The same problems apply when being in suspension, especially at angles close to vertical.

Subjects who faint while in vertical suspension are in danger of brain damage and within four to six minutes of fainting. I'm quoting from one of the studies here, but the fact remains for all suspension where the legs are lower than the head, venous pooling, and circulatory restriction, can lead to loss of consciousness. Unconscious suspended subjects can die in as little as ten minutes.

The study concludes that, "Whatever type of harness, hanging motionless in suspension is not physiologically safe, and will eventually lead to very serious blood circulation problems. In 1984, the first indoor experiments took place. The first subject was in a real situation, with his head in hyperextension and his legs dangling below heart level. The second subject wore a brace in order to eliminate the hyperextension of the head, his legs still dangling. Finally, the third subject had his head in hyperextension but with his feet in foot-loops, keeping his legs in a horizontal position. In all 3 cases, the subjects experienced considerable difficulties after 12 to 30 minutes of hanging. One of them actually fainted in spite of the medical controls and monitoring. Most of the testers believe that HHS is caused by blood being trapped in the legs so that the net result is similar to hypovolemic shock. No blood is actually being lost, but the amount of blood available in the torso to keep the brain and vital organs sufficiently perfused with blood is inadequate nonetheless. A second condition which might occur is compression or crush syndrome. This syndrome was associated with injuries that dealt with extremities being for a period of time. While the circulation is not occurring in the trapped leg, toxins (waste by-products of the cells) start to build up within the vessels of the trapped leg, below the compression. The body is always dealing with low, very low concentrations of these toxins without any ill-effects. However, when a crushed extremity (i.e., the trapped leg) is released, Deoxygenated blood, and the trapped toxins suddenly flow into the circulatory system and shocks the system. This will kill in seconds if not prepared - IV's a must prior to the release. However, this syndrome won't occur in seconds, but will in an hour or two. This also depends on how large the area is affected and if the circulation is completely or partially shutdown. Hanging MOTIONLESS in a harness, for long period of time will produce the same conditions in the legs as if it was trapped under a rock.

Tests and common sense indicate that the effects of suspension vary from individual to individual, and the type of harness, (or hemp rig) factors into the degree of restriction of circulating blood volume to the brain and kidneys.

Suspension trauma can develop extremely quickly. Vitals should be closely monitored, and the suspended person should communicate changes in a timely manner. Within five minutes into the medical tests, subjects noted tingling and numbness in hands and legs. Look for, Faintness. Nausea, Hot flushes. Sweats. Breathlessness. Feeling of panic or unwellness. "Greying" or loss of vision. Change in pulse rate (suddenly slowing or becoming rapid.) Signs of imminent circulatory collapse were: cold sweat, dilated pupils, giddiness, incipient nausea.

A lot of the signs and symptoms listed above, including the most important - fainting - may resemble a subject who is "flying", or a deep sub-space experience. This obviously compounds the danger of our activities, especially when playing with people who go into, or affect, near catatonic states.

If someone passes out in a suspension, get them out immediately. DO NOT place them in a horizontal (lying down) posture. They should be seated head elevated. This is completely counter-intuitive and opposite to treating for shock reactions. The violent release of deoxygenated, and possibly toxic blood volume, increased blood pressure and change in heart rate could seriously damage the heart, or release blood clots into the system.

You can lie them down, and elevate legs only in the early stages of recognizing symptoms. Otherwise, the majority of the studies recommend keeping the head elevated. Get some fluids into them, water, sports drinks, or something sweet. Pre-plan a pre-suspension diet that includes sufficient calories for energy maintenance, and enough fluid volume to prevent dehydration.

Warm them up. Hypothermic reactions are a major contributor to the syndrome, and you don't have to be soaking wet in a cave to become hypothermic. A few degrees below room temperature, (like you'll typically find in a public play space) will sap your core temperature, over time, as effectively as a wet cave. And in our play, we can usually count on additional stressors which can contribute to hypothermia: minimal clothing, fatigue, or exhaustion from resistance, or maintaining a pose, impact shocks, and endorphin release.

Ask conscious patients to do leg contractions to assist circulation. * Note to subs: This will also help you to prolong your suspension and mitigate problems if you can flex and pump your legs occasionally while tied.

Pre-plan, and invest in a rope cutter of a type used by professional rope rescue people, to actually cut rope, such as a diver's rope knife, a line cutter, scuba scissors, or whatever, because in my opinion, your omnipresent medical shears "aren't going to cut it" in a real emergency. I know this is a heretical statement, as shears have become almost iconic within the rope community. Sorry. Get over it. Hey, I carry one on my belt too, (if only so that I don't have to explain to people why I'm not carrying one. As everybody's an expert in Shibari nowadays) and as a firefighter, I use them all the time. Med shears are great for cutting fabric, because that is what they are designed to do. Hell, tales even are told that you can actually cut a penny in half with these wondrous tools! (Here your humble poster politely covers his mouth, and quietly coughs, "Bullshit,")(editor's note: as an EMT, I did actually cut a penny with my shears. It worked. It ruined the shears, and took about 1/2 hour. Pretty dumb thing to do.) but it takes too damn long to cut hemp with them. Try it yourself. I mean seriously try it. Actually cut a piece of your own rope with whatever grade of shears you own. Count the seconds it takes. If you're satisfied with the time, then so be it. But it took me twelve seconds to hack a piece of 8mm rope, and just under six seconds to cut a piece of 6mm. Imagine trying to work on multiple lines of 8mm rope when that four to six-minute window is starting to close.

Subjects who have fainted in suspension need medical attention. Inform arriving paramedics that the patient was suspended. Administer 100% oxygen, and provide circulatory assistance with IV fluids. Transport with head/chest elevated.

Hospitalize even with minor symptoms – eg. numb legs and transitory respiratory and circulatory problems. Be aware of the possibility of later death by renal (kidney) failure.

Evidently, ours is a more dangerous sport than many of us realized. We can kill people not only by accidentally dropping them, but by simply not noticing that they're dying.

Anyway, a long post, and a bit discouraging, but on the bright side, IRATA members (International Rope Access Training Association) who have collectively spent over six million hours working "in harness" contributed info to the above study, without much to report in the way of ill effects from HHS. It is hypothesized, however, that people who work on high rope are usually active, and are keeping their blood pumping, and thus are not susceptible to the syndrome.

Regards, Paul