Suspension trauma: how to manage a hidden killer

There is no doubt that stricter legislation and improved safety standards have made working at heights safer in recent years. There are many elements to height safety and employers have geared up on the equipment side especially. Apart from supplying the equipment itself, the necessity to provide training on how to use it has also become a main driver for employers.

Although this sounds very promising, there is one aspect of height safety training that seems often to get neglected. What happens if things go wrong? Is there a plan for rescuing a suspended person? Can this plan be put into effect within ten minutes?

Who hasn't seen a person fainting at a funeral after standing still for several minutes? This can happen to anyone at any time. It is not a matter of bad fitness, exhaustion, injury or hanging in a harness. The phenomenon of 'suspension trauma' is caused when a person is held in an upright position without the possibility of moving their legs. And being suspended in a harness will enhance one's chances of becoming a victim of suspension trauma.

The human body seems to have a design error in that the heart is strong enough to pump the blood into every inch of the body, but fails to get it back into the heart and into the organs. This job is normally done through the contraction of muscles, primarily in the legs. Standing still in an upright position will slow the return flow into the upper body and will eventually stop the blood flow completely. This will create a pool of blood in the legs, the result being a blood shortage in the brain. The brain will recognise this shortage and assume that there must be a significant blood loss somewhere in the body. To compensate for this blood loss it wants the body to lie down, and therefore allows the person to faint. This will get part of the blood from the legs back into the heart and into the brain and the body will recover in time.

In the context of height safety, the problem can start if a person is fixed in an upright position for an inordinate amount of time (ie, in a fall arrest harness). The person will still faint but the recovery process cannot start automatically in the manner outlined above. Worse still, the blood pool in the legs cannot be detoxicated by transferring it through the organs as it is trapped in the legs. In this scenario the person is only minutes away from death. Moreover, if the rescue of the person is conducted using incorrect procedures, the person will most probably die due to the accumulation of toxins in the blood that will almost certainly poison the body.

The standard AUS/NZS 1891.4-2000 'Industrial Fall Arrest Systems and Devices Part 4: Selection, Use and Maintenance' states that clinical tests have revealed that people do react differently to suspension effects but makes it clear that in some cases the effects start to settle in after only a few minutes. This fact requires every user of height safety equipment to have an emergency rescue plan in place which enables an effective rescue of the suspended person within a relatively small time frame (eg, 10 minutes).

Proper training on how to prevent a suspension trauma and how to safely rescue a person from a suspended position is therefore the key to avoiding accidents and fatalities.