What is succinylcholine?
Succinylcholine is the generic name (brand name examples include Anectine and Quelicin) of a neuromuscular blocking drug that induces paralysis, and is often used to relax a patient prior to placement of a breathing tube (aka intubation or placement of “trach” or tracheostomy). In fact, rapid sequence intubation is commonly used in the Emergency Department as an aid to intubation, or placement of the breathing tube. There is a specific sequence of drugs that has been shown to be very useful in accomplishment of this goal, but there are precautions indicated. One of the primary RSI (rapid-sequence intubation) drugs is succinylcholine, a potent paralytic drug that is similar to curare.
Dangers of Succinylcholine
The use of succinylcholine in hyperkalemic patients (serum potassium >5.5 mEq/L) is contraindicated (not recommended). Since the 1950’s, physicians have recognized the potential for patients with injuries that result in cellular damage to accumulate high levels of potassium in their serum, after injuries that specifically include crush or burns. Potassium is a very important cellular cation, or molecule, that moves in and out of cells in the body and results in change of the electrical potentials in those cells. One of the most important groups of cells that are dependent upon potassium is the myocardium. This term refers to the muscular cells of the heart.
Myocytes are the cells that make up the heart. The heart depends upon a physiologic electrical current to transmit an impulse from the “pacemaker” cells to the rest of the cardiac cells. This impulse results in contraction. The impulse causes transmission of an electrical signal from the atrium, the outermost chamber of the heart, to the ventricles, the workhorses of the heart.
If the potassium level in the blood is too high or too low, this results in aberrant, or abnormal, conduction of signals. When the electrical system of the heart is not working properly, there is a failure to maintain an appropriate rhythm. This condition is known as an arrhythmia.
Some arrhythmias result in death, because if the heart does not conduct and contract properly, it has no ability to pump blood from the lungs to the body. This is the way the body supplies itself with oxygen, and if the heart is not pumping correctly, it may result in tissue hypoxia, or low levels of oxygen in the body’s tissues. The body’s tissues have metabolic needs that will result in cell death if they are not fulfilled. Oxygen is probably the most important of those needs.
When the cardiac cells die, whether part of the conduction system or of the muscles of the heart, there is a tremendous potential for death. The heart is amazingly tolerant of many substandard conditions, but a lack of oxygen is a critical determinant of cell death.
When patients with a burn or crush injury undergo intubation (placement of a breathing tube), they may already have abnormally high levels of potassium circulating in their bloodstream. This is because of the release of potassium from destroyed cells. If these patients receive succinylcholine, then because of the abnormally high circulating potassium levels they can develop a deadly hyperkalemia.
Many disease states, including elevation of the blood pH, result in excess potassium in the bloodstream. Potassium is utilized in lethal injection, so it should be clear that this electrolyte has an influence on the heart. If a crush injury or a burn has resulted in release of potassium into the bloodstream from cell destruction, then it is important to be aware of this and of the potential for additional problems caused by succinylcholine. This drug should be used cautiously in patients with renal failure or skeletomuscular injury. The up regulation of certain receptors for acetylcholine can result in the release of potassium from muscle fibers that are already depolarized.
Should You Contact A Lawyer?
If you or a loved one has suffered a cardiac arrest after an injury that may include a motor vehicle collision with a prolonged extraction time (crush), then you should consult with a malpractice attorney to ensure that you were not improperly treated with succinylcholine. If this was the case and if you have significant damages, you may have some recourse under the law. The actions of succinylcholine on potassium in patients with predisposing conditions are well understood and should be considered by any physician treating emergent cases. Call Passen & Powell today at 312-527-4500.