Crush syndrome isn’t discussed much in the limelight of EMS nor in classes that we take to prepare for the lifesaving career that we selected. What is crush syndrome? What we can do about it when we’re confronted by it on scene?
I have had numerous conversations with EMTs and paramedics who had absolutely no idea what crush syndrome, or rhabdomyolysis, is. In fact, I didn’t learn about this until I was faced with it as an EMT. Thankfully, my paramedic partner knew what was going down. I don’t want you to be in the shoes of not knowing, because this is a very, very big deal.
Potassium, other substances
Crush syndrome derives from crush injuries that involve soft tissue, primarily skeletal muscle of the extremities. Remarkably, crush syndrome can start in as little as 20–30 minutes after an injury occurs. However, critical levels of the following elements really start to pose a serious threat an hour or more after the injury.
When an object crushes the extremities and tissues, it damages the muscle cells themselves. When the muscle cells are damaged, the resulting effect is that they release/leak numerous substances. The most important of these leaked substances are potassium, lactic acid and myoglobin.
We can think of it with this analogy: Imagine that the body’s vascular system is a beautiful, flowing creek. Then those pesky beavers build a dam across the creek, which causes some serious backup of the flowing water. (The dam equates to the crushing object at the incident.) The backed up water in the creek becomes stagnant.
Biproducts of the damaged creek, such as animal feces, algae and bacteria, build up to create a nasty, swamp-type environment. In the body, potassium is the feces, lactic acid is the algae and myoglobin is the bacteria, and the “swamp” forms on the distal end of the extremity.
On the proximal side of the “dam” is that beautiful, bright, crystal blue water that is the rest of the vasculature of the body.
The mistake that’s made and ultimately takes the life of the patient is blowing up the dam (removing the crushing object) too soon. So, what do we do about it?
Treatments
EMTs and paramedics must understand all of these elements that are in the nasty swamp of a distal extremity.
Potassium is an intracellular-based electrolyte that assists with muscle contractions. When it’s released in great volumes into the circulatory system, it can have a profound effect on the heart. Large amounts of potassium can place the heart into cardiac arrest or other cardiac arrhythmias.
Pretreatment for hyperkalemia (high potassium) consists of giving the patient calcium chloride as well as continuous albuterol treatments to push the potassium back into the muscle cells.
A sign of hyperkalemia are tall T waves on a 12-lead EKG. If you have the ability, collect 12-lead EKGs as soon as you can and then every 30 minutes to continuously monitor for hyperkalemia.
Next is lactic acid. The human body runs a little on the alkaline side of the pH scale, normally measuring 7.35–7.45. When the body begins to exert energy—or when muscle cells are damaged—a biproduct is lactic acid. The body doesn’t enjoy this, because it’s irritating. It’s the reason why we lose our steam when it comes to exertion. When you, for example, run a mile, lactic acid builds up, which ends up causing your pace to slow down.
Treatment is sodium bicarbonate. Give the patient 50 mEq bolus, followed by another 50 mEq in a 1000cc bag of isotonic crystalloid.
Lastly is the nastiness that is myoglobin. Myoglobin is a sticky protein that’s used during times of exertion or muscle damage. In regard to the latter, the myoglobin is released from the muscle cells and then gets trapped in the loop of Henle in the kidneys. This causes acute blockages and lack of perfusion, which in turn leads to renal failure.
Treatment for this is fluids, fluids, fluids. You want the patient to have approximately 1–1.5 L per hour to maintain renal perfusion.
Pretreat the patient
Of course, this is a brief overview, and the particulars of crush syndrome can get much more in depth. The most important aspect to take away from this article is take your time and pretreat your patient. If a patient has been crushed by an object and you don’t pretreat, that swamp water will contaminate the rest of the creek and cause serious problems.
Treat the patient and then lift the object.
