Suspension_Trauma

INFORMATION ON
Recognising, Preventing and Treating Suspension Trauma
Introduction
Suspension trauma is a term used to describe the condition where a person is trapped in an upright position and is unable to move; blood is trapped in the person’s legs and is unable to recirculate back into the heart efficiently. As a result, the cardio-respiratory system of the person is unable to function properly, which can result in the fatal condition of oxygen starvation of the brain or other vital organs. Another name for such a condition is ‘Harness Hang Syndrome’. For work activities at height, workers who wear safety harnesses are subject to this condition, should they fall and be left in a vertical, hanging position. Although suspension trauma is considered a rare occurrence, the effects of mishandling or neglecting a victim can be lethal or severely damaging. Hence, there is the need to raise the awareness of such a hazard and the measures for preventing and treating such a condition.
How does it occur?
Blood is pumped out of the heart and travels through the body, including the legs. Due to gravity and the density of blood, the heart is unable to draw the blood back. Normally, muscle contractions in the legs force the blood back towards the heart and thus, there is little or no danger. This system is especially effective when a person runs or walks, but less so when standing still, as the muscles are less active. However, should leg movements be restricted or a person is suspended and the leg muscles are not engaged, blood flow from the legs may be restricted. Additionally, harness straps may constrict veins and aggravate the problem. This is known as venous blood pooling and it can result in fainting, due to the reduced re-circulation of blood from the legs. Over time, if the person remains in the upright position despite being unconscious, the brain and other vital organs such as the kidneys will be deprived of oxygen.
A person left suspended in a harness after falling experiences a lack of blood flow back into the heart, as the muscles in the legs are not active. If the person remains suspended and is not rescued promptly, injury or death may result.
Recognising the Symptoms
As blood is accumulated in the legs, the amount of blood in circulation will decrease. Attempting to re-establish blood flow to the brain, the human body will attempt to go into a state similar to shock in order to compensate by increasing the heart rate and breathing rate. There may also be an attempt to shift blood from the surface of the skin to provide more blood for vital organs. This results in the following possible symptoms:
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Breathlessness Excessive perspiration
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Increased heart rate Nausea

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Paleness of the skin Hot flashes
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Dizziness
If the condition of insufficient blood in circulation persists, the human body will attempt further measures by slowing the heart rate, resulting in lowered blood pressure in the arteries. This can cause the following symptoms:
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Unusually low heart rate Unusually low blood pressure
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“Greying” or loss of vision
Eventually, as the oxygen received by the brain decreases, unconsciousness sets in. Other vital organs may also be affected by the lowered amount of oxygen. In particular, the kidneys are very vulnerable to insufficient oxygen and renal failure may result. When a person is unconscious, there is the additional risk of suffocation, as the tongue may obstruct the airway. Should the situation be left to develop unchecked, the consequences can be fatal, due to oxygen starvation of the brain.
Timing and Onset of Symptoms
The amount of time for a person to experience the initial symptoms of shock, as described above, can be as little as three minutes, although it was known that the average time is between five to twenty minutes. Unconsciousness will set in within a few minutes after the initial symptoms occur. A few minutes after the onset of unconsciousness, death may result due to oxygen starvation of the brain. Physical factors such as fitness level, height, weight or ethnicity do not affect the amount of time needed for suspension trauma to set in. In fact, the same person may react differently from one day to the next; therefore, where time is concerned, it is not predictable. However, the following conditions have been known to affect the degree of risk due to suspension trauma.
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Inability to move the legs Pain Injuries Fatigue Dehydration
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Hypothermia * Shock Cardiovascular disease Respiratory disease Blood loss
* Extremely low body temperature, due to exposure to cold weather
Prevention Measures for the Victim
Should a person be suspended in a harness after falling, the rescue of that person should take place promptly. It is highly recommended to provide training in self-rescue techniques for workers required to wear fall arrest harnesses. If self-rescue is not possible, while awaiting rescue, there are basically three methods that the suspended person can employ to prevent the onset of unconsciousness and the ill-effects of venous pooling. 1. Move/lift the knees above the hip level By lifting up the knees above the hip level, blood pooling is reduced and thus the risk is also reduced; even a ‘sitting’ position is better than a completely vertical posture. To help maintain such a posture, supports such as a strap, a rope or even improvised materials such as a long

strip of cloth or clothing can be used. There are also specially designed suspension trauma straps available to prevent or delay suspension trauma. 2. Pushing against a solid surface However, certain harnesses may not allow for the lifting of the person’s knees. In this case, the person should attempt, where possible, to move their legs and push against a solid surface with either the legs or feet. This would cause the legs to pump blood back into the heart. This method is somewhat less preferable to the first, as the muscle exertions will cause more blood to be pumped into the legs, which may add to the problem. Additionally, a solid surface needs to be close enough to push against. The use of a separate rescue line for the victim to step on is also possible.
By providing a step for the victim, the venous pooling in the legs is relieved.
3. Perform a cycling motion with the legs This method is the least preferable as the cycling motion would cause more blood to be pumped into the legs to support the activity. In addition, once the person starts the cycling motion, stopping (perhaps due reasons such as to fatigue or pain from injuries) would cause the blood pooling to occur. Due to muscle usage, the flow of blood into the legs is increased, compounding and accelerating the effect. This method should be used only if there is no other option available.
Rescue and Treatment
It is beneficial to carry out drills to familiarise rescuers with the procedures. Here, a weighted dummy is used for rescue practice.
Due to the relatively short time needed for the onset of the ill-effects of suspension trauma, it is not enough to solely rely on emergency services to provide rescue. Where work is to be carried out at height, plans to rescue suspended workers must be created.

Rescue While it is possible to call upon emergency services (such as the SCDF) for purposes of rescue, it is possible for unexpected conditions, such as traffic congestion to delay the arrival of help. Hence, it is vital for workplaces where work at height is carried out to prepare emergency rescue procedures, and equipment, as well as appointing and training rescuers. An effective way to prepare the rescue procedures is during the risk assessment process. When planning for rescue, consideration should be given to the type of situation from which the victim may need to be recovered and the type of fall protection equipment which the victim would be using. Some situations may create difficulties, for example, a remote victim who is suspended out of reach or the need to perform rescue over an edge. The load placed on some of the equipment during a rescue may be higher than they have been originally designed for. If equipment is intended for use in rescue, the manufacturer should be consulted. It is critical that such equipment has suitable performance and loading characteristics when used for rescue purposes. When considering rescue methods, always attempt to minimise the risk to rescuers. Avoid placing additional personnel at risk, whenever possible. The type of rescue procedure that is required will depend on the specific circumstances. Below are some examples: ? If the suspended person is low enough to the ground, the lanyard can be detached or cut and the person can be lowered to the ground manually. ? Use a MEWP that is positioned near to the work area to reach the suspended person. ? Competent and trained rescuers using a suitable type of rescue kit that can be quickly and effectively deployed to the point of rescue. Such kits are available from most manufacturers of equipment for work at height. However, this method is less preferable, as it will result in additional loading on all parts of the system including the anchor, which may be required to support the load of two persons, placing the rescuer at risk. The rescue plan must cover both scenarios of conscious and unconscious victims. Ideally, the rescuer should be able to communicate with the victim at all times or see the victim at all times or communicate with someone who is able to see the victim at all times. Certain precautions are needed when treating or caring for victims of suspension trauma. This is mainly due to the risk posed by Reflow Syndrome, as outlined below. Reflow Syndrome Due to the blood remaining in the legs for extended periods of time, the oxygen and nutrients in the blood are still consumed by cells. When the oxygen is used up, the cells start to perform anaerobic metabolism on the fatty tissue in the legs to continue functioning. The toxic byproducts formed during such a process during vigorous exercise are normally kept at a low level by increased blood flow. However, during suspension, blood flow is very low and the level of toxicity can reach dangerous levels within a short period of time. Should the trapped blood be allowed to flow back rapidly to the rest of the body, the presence of the toxins and the low level of oxygen can cause serious problems. The heart may stop, the kidneys and brain may be damaged; in certain cases, death may follow shortly. This can happen if the victim is made to lie flat on the floor immediately after rescue.

First Response Any extent of suspension trauma will result in reduced blood flow to the brain. The symptoms of shock, if left untreated may result in unconsciousness. This, in turn, can cause blockage of the airway and the death of the victim. In addition, the low oxygen level in the blood can lead to brain or organ damage or even death. Positioning of the Victim After Rescue The primary goal of the rescuer is to return oxygen supply to the brain while preventing Reflow Syndrome. Therefore, in the initial 20-40 minutes after rescue, the victim should never be allowed or be made to lie down on the floor, even for an instant, unless there is the need to perform CPR. The victim should be moved first into a kneeling position and then subsequently into a sitting or “huddled” position, with the legs slightly bent at the knees. This will reduce the pooling effect of gravity, but will keep most of the pooled blood in the legs, preventing reflow.
A sitting/squatting recovery position is the recommended position to place the victim after rescue from suspension. Unconscious victims need help to remain in such a position.
A normal symptom is that the victim will feel some numbness in the legs; this should subside. However, if the victim has suffered no injuries, yet complains of great pain in the legs, especially when the victim is being moved, a severe condition called Compartment Syndrome may have developed. Faced with Compartment Syndrome, as a rescuer, there is nothing more that can be done except placing the victim in a sitting position and summoning an ambulance with utmost urgency. Conscious Victim Prevention measures may be used if there is no immediate way to remove the victim from suspension provided the victim can be reached and can follow instructions. The victim can be instructed to lift his knees above the hip level using a sling, a rope or material such as cloth or clothing. There are also suspension trauma belts that are designed for such purposes. If the victim cannot be repositioned or be removed from suspension immediately, they must be monitored closely as unconsciousness is expected to set in at some point in time. The priority then is to maintain a clear airway in the victim’s mouth (by tilting the vioctim’s head slightly backwards after ensuring it is clear of objects) and arrange for urgent rescue. The first thing to do after the victim is released from suspension is to make him sit with the torso upright, with the knees slightly bent. The victim may feel weak or dizzy and may need assistance to prevent him from collapsing onto the floor, where reflow may occur. The victim should not be allowed to stand up, exercise and consume any food or drinks. Medication or other types of fluids should not be given to the victim, unless the rescuer is medically trained and is aware of certain urgent need. The victim should be kept as calm and relax as possible; this is to reduce effects of stress on the victim’s heart rate.

Unconscious Victim Similar to the conscious victim, if immediate rescue is not possible, but the victim can be reached, the victim’s knees may be lifted and held in position by a strap, rope or material such as cloth or clothing. This will prevent further venous pooling from occurring in the legs. An unconscious victim is an indication that venous pooling of blood in the legs had already developed over time. Therefore, the level of toxins in the pooled blood is expected to be high and the victim must not be allowed to lie flat immediately after being released from suspension. The victim’s airway must be kept clear and the body moved into a sitting position. The exception is where CPR is required, since without a heartbeat, the reflow effect will not occur. Also, the circulation due to the application of CPR is not strong enough to cause reflow syndrome. However, the cause of the unconsciousness may be due to another factor, such as being struck by an object or electrocution. If the cause of unconsciousness is due to other factors and the victim is released from suspension within 10 to 20 minutes, the victim can be made to lie flat. If the length of suspension is too long, or the cause of unconsciousness is not clear, the sitting position must still be adopted. Need for Victim to be Sent to Hospital As a general rule, the victim should be sent to the hospital for blood tests if suspension had occurred for more than 10 minutes, even if there are no noticeable injuries. A fully conscious and aware victim may be conveyed to hospital in a private vehicle. Should an ambulance be called, there is a need to inform the crew on the nature of the injury; that it is not a normal case of unconsciousness. In addition, the crew must also be informed that the victim is not allowed to lie down too soon (within 10 to 20 minutes) after being released from the suspended position.

Further Information 1. https://www.360docs.net/doc/1e11577825.html, https://www.360docs.net/doc/1e11577825.html,/ 2. OSHA - Safety and Health Information Bulletin on Suspension Trauma/Orthostatic Intolerance https://www.360docs.net/doc/1e11577825.html,/dts/shib/shib032404.html 3. The Work at Height Safety Association, Technical Guidance Note 5 - “Guidance on rescue during work at height” https://www.360docs.net/doc/1e11577825.html,/component/option,com_docman/task,doc_download/gid, 5/ 4. Will Your Safety Harness Kill You? Bill Weems and Phil Bishop (Taken from Occupational Health & Safety magazine, Vol. 27, No. 3, pages 86-90, March 2003) https://www.360docs.net/doc/1e11577825.html,/elcosh/docs/d0500/d000568/d000568.html
The Workplace Safety and Health Council wishes to acknowledge the following organisations for the diagrams used: ? ASRETEC Pte Ltd