Earlier this year in Texas two window washers became stranded on the side of a commercial building approximately 15 stories above ground. They were working off of a mobile scaffold which failed.
Thankfully, the workers were complying with safety regulations and wearing harnesses, which were rigged to safety lines. The result was two very viable victims who were dangling on the side of the building as opposed to two fatalities that were critically injured on the ground or hanging precariously on the scaffolding.
On the surface, this sounds like a stable rescue sequence with relatively benign hazards to the victims. However, there is an underlying mechanism that presents a significant risk to the workers and it is extremely time and equipment sensitive: suspension trauma.
Suspension trauma is also referred to as orthostatic intolerance. Here’s how OSHA defines this trauma.
Orthostatic intolerance may be defined as "the development of symptoms such as light-headedness, palpitations, tremulousness, poor concentration, fatigue, nausea, dizziness, headache, sweating, weakness and occasionally fainting during upright standing." While in a sedentary position, blood can accumulate in the veins, which is commonly called "venous pooling," and cause orthostatic intolerance.
In the veins, blood normally is moved back to the heart through one-way valves using the normal muscular action associated with limb movement. If the legs are immobile, then these "muscle pumps" do not operate effectively, and blood can accumulate. Since veins can expand, a large volume of blood may accumulate in the veins.
An accumulation of blood in the legs reduces the amount of blood in circulation. The body reacts to this reduction by speeding up the heart rate in an attempt to maintain sufficient blood flow to the brain. If the blood supply is significantly reduced, this reaction will not be effective. The body will abruptly slow the heart rate and blood pressure will diminish in the arteries. During severe venous pooling, the reduction in quantity and/or quality (oxygen content) of blood flowing to the brain causes fainting. This reduction also can have an effect on other vital organs, such as the kidneys. The kidneys are very sensitive to blood oxygen, and renal failure can occur with excessive venous pooling. If these conditions continue, they potentially may be fatal.
This physiologic event is the body’s response to compression points. Harnesses have different design features, but most apply compression to the upper legs.
Additionally, shock absorbers or arrestors are recommended or required in most fall-arrest systems to slow the descent of a falling load or victim. This also helps reduce the significance of the initial impact and compression to the victim and to the anchors and equipment they are rigged to.
So, how does suspension trauma play a direct role in this rescue sequence and how do we manage it as rescuers? Here’s a look at six steps to reduce this risk to victims.
1. Work fast
There is no definitive time table for the onset and progression of suspension trauma. There are several contributing factors including obesity, cardiovascular disease, environmental conditions, additional injuries, shock and age. But, in typical rescuer fashion, assume the worst and work toward minimizing or mitigating that worst-case scenario.
Documented cases of fatality due to suspension trauma have occurred in just under 30 minutes of suspension without movement. That’s pretty fast, and will require all rescuers to work efficiently.
Try to assess the victim as quickly as possible from a remote visual or verbal perspective and attempt to evaluate their ability to move and shift weight. If they are unconscious or immobile, the clock is ticking.
Also, recognize the early symptoms of suspension trauma. If the victim appears confused and lethargic and you can rule out a head injury or an unrelated medical emergency, then the most likely culprit is suspension trauma and things are progressing quickly.
If the victim can be verbally coached to shift their body weight, lean back in their harness and keep their legs moving, that is the first step toward a good outcome and will buy the rescue team time.
2. Access the victim
Quickly determine whether the victim will be accessed through a nearby window, from an aerial platform or from the rooftop. Each of those approaches require different set ups and different tool loads. Here, we will focus on the rooftop application.
Rescuers will need to get on the roof and establish appropriate anchors. This is not always as easy as it sounds. Commercial roofs can have limited anchors, which can cause uncertainty and under-engineered rigging decisions.
Avoid tunnel vision and seek a singular bomb-proof anchor. These often don’t exist on rooftops and may result in rescuers selecting a vent pipe or something that may not provide adequate strength and reliability. Be prepared to think outside of the box and come prepared.
Additional rope is always good when on a roof. Rope can be used to wrap structures and multiple elements to create reliable anchor systems. The access point to the roof will almost always provide a segue to more anchor options, as will elevator penthouses or other utility-based rooftop structures.
Once the anchor is established, set up for a pick off. This will typically require a single main line and a belay. The next decision is whether to establish a fixed brake or a moving brake. There is a lot of discussion on this topic within the rescue community.
A fixed brake means that a descent-control device is rigged to the top side anchor and the rescuer will be lowered to the victim. The advantage of this is that the rescuer will not have to manage a device and is free to use both of his hands throughout the sequence.
Additionally, there is no rope hanging under the rescuer since he is attached to the end of the rope. This can be a significant advantage when working at extreme heights, particularly when high wind is present.
The disadvantages are communication and movement. The rescuer and the lowering operator must maintain constant communications to safely and effectively manage the speed of descent and the stop and go points.
This can be more challenging than it sounds. High winds swirling around tall building can hinder verbal communication, requiring line-of-sight edge tending and hand signals to communicate.
The moving brake application places the descent control device with the rescuer so that he is traveling on a fixed line that has been lowered to the ground. The advantage to this is the rescuer has finite control over his position on the wall and speed and movement on the rope. There are no delays in commands or communications.
The disadvantage is that the rescuer has to manage the device, which may become challenging if he encounters a panicked victim who jumps or reaches for him.
Also, all of the rope hanging down below the rescuer has to be tended to and can add challenges to the rescuer. Winds can take the running rope and wrap it around the other face of the building and in extreme heights, the rope weight alone requires a more advanced rappelling skills to manage.
Both approaches should be in your tool box and applied based on the event, the victim and the expertise of the rescuer.
3. Secure the victim
Rescuers should stop their descent slightly above the victim. Make an initial safety attachment to secure the victim. This can be accomplished in a number of ways, but is often done by pre-rigging the belay.
When the rescuer is rigging in on the top side, put a figure eight on a bite on the end of the belay. This will be the victim’s connection point. Then pull an arm’s length of rope from the figure eight and place a midline knot.
This length of rope needs to be appropriate for the gap or distance that will be between the rescuer’s attachment point and the victim’s attachment point; an arm’s length accommodates most pick-off straps or mini hauling systems for securing the victim and managing the gap.
A butterfly is often used for this knot since it is designed for three-way loading. Then attach the midline knot, or butterfly, to the rescuer’s harness connection and the tail with the figure eight on a bite secured to the rescuer’s utility loop.
Once the rescuer reaches the victim, she detaches the figure eight on a bite and connects it to the victims harness connection. For speed, I prefer to use hardware for these connection in these scenarios. Other options include a dedicated belay for the victim and various progress-capture devices that can be rigged to the rescuer mainline or belay line.
4. Transfer the victim
Once the victim is secured, we need to transfer their load from the tensioned system they are suspended from to the rescuer’s system. This also can be accomplished in a number of ways, but we will discuss the mini haul application.
Mini hauling systems are most commonly small, simple systems (4:1/5:1) with integrated progress capture components. The rescuer attaches the system to the main line, not the harness rigging point.
For example, if the rescuer is rappelling, she would attach the system to the eye of the rack. This ensures that the victim’s load is on the main line and not on the rescuer.
The other end of the system is then attached to the victim’s harness connection. Once the system is in place, the rescuer then hauls on the system thus bringing the victim up and taking the load off the victim’s system. The victim’s system can then be disconnected.
In industrial applications, the victim’s connection will often be a dorsal connection and be a steel cable or rope. Take time to analyze the connection and the system before disconnecting.
5. Lower the victim to safety
With the victim secured and transferred, the rescuer is free to descend. I prefer to have the victim facing me and their back against the wall. I also prefer the victim keep their hands on their chest so that they are not tempted to grab my feet or legs.
It is important for the rescuer to maintain foot contact with the wall. This allows the rescuer to control the victim’s proximity to the wall and helps insure safe and deliberate movement while descending. If the victim grabs your legs, they will pull your feet off the wall.
6. Manage suspension trauma
If the victim is exhibiting signs and symptoms of suspension trauma or are unconscious, avoid quickly transitioning the victim to the supine position. Placing the victim flat on their back will allow all of the toxins that have pooled in their lower extremities to flood their circulatory system and will most likely result in cardiac arrest.
Some protocols and medical control will advise intravenously administering sodium bicarb, but there is some controversial data regarding the long-term effectiveness of this intervention. The most agreed upon treatment involves a slow progression through the various Fowler’s positions.
Try to position the victim in the upright seated or full Fowler’s position for at least five minutes before transitioning them to a semi Fowler’s position. Each movement towards lying flat should be done in no less than five-minute increments. IV access and fluid resuscitation are also routine requirements.
Be aware of the dangers for suspended victims and move with a purpose. Stay safe and train hard.