What Does Suspension Trauma Mean?
Suspension trauma is a form of ill health that results when an individual is suspended in a relatively immobile position for an extended period of time. It is an exacerbating danger faced by workers who fall from height and are left suspended from a fall-arrest system until rescued.
The symptoms of suspension trauma include light-headedness, palpitations, fatigue, nausea, dizziness, headache, sweating, and weakness, and this can eventually lead to unconsciousness or death.
Safeopedia Explains Suspension Trauma
In the medical field, the symptoms caused by suspension trauma are referred to as orthostatic syndrome, orthostatic shock, or orthostatic intolerance. This type of trauma is caused by “venous pooling”—a pooling of blood in the legs that results from the suspended individual’s legs being relatively immobile. The lack of blood circulating through the body due to venous pooling results in an increased heart rate to maintain sufficient blood flow to the brain; if this is not effective, it leads to an abrupt slowing of the heart rate. Severe venous pooling can lead to fainting or the failure of blood-deprived kidneys.
Suspension trauma symptoms can begin after a few minutes but typically take about 20 minutes to onset. However, experiments in harness design have found that loss of consciousness can occur within seven to 30 minutes. Particular dangers that are posed by suspension trauma as opposed to more general orthostatic intolerance relate to the role of the harness in restricting movement and controlling the position of the individual. A harness that keeps an individual upright and provides no leverage for the legs (e.g. foot straps) would result in a worker being held in a position that is more susceptible to suspension trauma than a harness in which a worker is at a steeper angle with the ability to move or adjust his or her legs more freely. The extent to which a harness could restrict the circulation of the wearer is also a factor.
Many publications advise that individuals who have suffered suspension trauma are at risk of suffering “reflow syndrome” or “rescue death” after being rescued due to rapid return of unoxygenated blood from the legs to the rest of the body. The first aid prescribed to prevent this is to keep rescued patients in a knees-up, sitting-up position. A review published by the UK Health and Safety Executive found that there is no scientific evidence demonstrating the existence of reflow syndrome, and it recommended that suspension patients be placed in a fully horizontal position for recovery.