Suspension trauma is a serious physiological condition affecting individuals suspended upright without movement, commonly in occupations involving harnesses like working at heights. Understanding this condition is important for prevention and emergency management. This article explains its nature, development, indicators, and crucial prevention and response strategies.
Understanding Suspension Trauma
Suspension trauma, also known as harness hang syndrome or orthostatic intolerance, occurs when a person is held upright and motionless for an extended period. Gravity causes blood to pool in the lower extremities, reducing the volume returning to the heart and decreasing overall circulation. This impairs the body’s ability to supply oxygen to vital organs.
How Suspension Trauma Develops
The physiological progression of suspension trauma begins with venous pooling, where blood accumulates in the legs due to gravity and lack of muscle movement. Normally, leg muscles contract to pump blood back to the heart; without this activity, up to 20% of circulating blood can become trapped in the lower limbs. This decreased venous return causes the heart to pump less blood, diminishing cardiac output. Consequently, the brain and other vital organs receive insufficient oxygenated blood, potentially leading to cerebral hypoxia and ischemia. Harness leg straps can exacerbate these effects by constricting blood vessels, further impeding circulation.
Recognizing the Signs and Symptoms
The signs and symptoms of suspension trauma can develop relatively quickly, sometimes within a few minutes, though often after 20 minutes or more of suspension. Initial indicators may include lightheadedness, nausea, and sweating. Individuals might also experience paleness, dizziness, or a tingling and numbness sensation in their legs. As the condition progresses, visual disturbances, such as blurred vision or “graying out,” can occur. Without intervention, more severe symptoms like confusion, disorientation, and eventually loss of consciousness may manifest. In extreme cases, prolonged suspension can lead to shock, organ damage, and cardiac arrest.
Prevention and Emergency Response
Preventing suspension trauma involves proactive measures and preparedness, including proper training for individuals working at heights, correct harness fitting, and regular equipment inspection. Minimizing suspension time is also crucial, achievable by using foot stirrups or encouraging movement like cycling the legs to promote blood circulation.
In a suspension incident, prompt rescue is essential. The suspended individual should be brought to a horizontal position as quickly as possible, but avoid immediate, full vertical elevation, as a rapid return of pooled blood can lead to “post-rescue collapse” or re-perfusion injury.
After rescue, place the individual in a recovery position, such as lying on their back with bent knees or in a “W” position, to gradually restore circulation. Monitoring vital signs and seeking immediate medical attention are essential, even if the person appears to recover, due to the risk of delayed complications.