One day Laurie Lemon went to the Mayo Clinic (Jacksonville, Florida) to remove the subcutaneous fat that had appeared on her elbow. Lipoma treatments are not considered extraordinary. An anesthetic is administered to the patient in the problem area, and then the surgeon proceeds to the usual manipulations. This procedure cannot be performed without anesthesia. Laurie surprised the doctors a lot: none of the painkillers offered to her had absolutely any effect.
This feature began to develop from childhood
The anesthesia literally enveloped the nerves on the patient's elbow, but they were still tender. Resistance to anesthetics is rare, but our heroine has been aware of this feature for as long as she can remember. One day, at the age of seven, she went to see the dentist. All the necessary pain relief actions were carried out, but soon a piercing children's cry was heard in the office. The injection did not work, and the girl informed the doctors about it. Pain relief by repeated injection was also unsuccessful. Then she steadfastly had to endure all the hardships of the painful treatment procedure. But now she faced a bigger problem. Mayo Clinic anesthesiologist Stephen Klendenen was the first to encounter such a case in his practice. He decided to study the phenomenon of his patient.
What does anesthetic resistance lead to?
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When local anesthetics do not work, many of the now familiar surgical procedures are threatened: from removal of a wen or appendicitis to cardiac catheterization. But in the medical literature there are several references to such cases. It turned out that every such precedent baffled doctors. No one could tell why the bodies of these patients resist the influence of anesthetics. And even more so, Dr. Klendenen did not find information on methods of treating resistance. There was only one chance that could somehow clarify the situation: a genetic study of the patient Laurie Lemon and her family.
The experience of London doctors
Klendenen needed to look for allies, and he found them in the person of Alan Hakim, an anesthesiologist at University College London. 11 years ago, a British doctor wrote about a problem he discovered in patients with Ehlers-Danlos syndrome, a rare genetic abnormality in which there is a defect in connective tissue. When Dr. Hakim observed patients with this condition, many of them complained of pain that they had to endure due to the resistance to local anesthesia. The specialist realized that in this category of patients the problem could be widespread, however, research into the causes (due to the rarity of the genetic disease) was not carried out. Nevertheless, there are several hypotheses that explain the essence of the phenomenon.
The absorption of the drug is prevented by the difference in the tissues
Soft tissues in patients diagnosed with ED is different from the tissues of healthy people, in whom pain relief is achieved by blocking sodium channels with the drug. Thus, positively charged sodium ions (as well as pain) do not reach the nerve endings.
Solutions
Sometimes the nerves themselves can be located slightly away from the place of medical manipulation. This is often encountered by dentists who re-inject pain relievers by changing the injection site. Sometimes, for the best effect, articaine is used, which dissolves better in subcutaneous fats and instantly penetrates the nerve membrane. In some cases, a technique called local blockade is used, in which the anesthetic is injected directly into the nerve. Dentists also resort to this practice if the tooth is too neglected and will have to be drilled, affecting adjacent nerves. However, no one ever goes into the details of their patients' resistance.
Missense mutation
The uniqueness of Laurie Lemon's case is that she does not have Ehlers-Danlos syndrome. This means that the answer to the question had to be looked for somewhere else. After a genetic analysis, it turned out that in the genome of members of the Lemon family, there is a defect affecting the channel, called "sodium 1.5". This anomaly is called a missense mutation. Previously, these sodium channels were considered only in connection with cardiac activity. The case of Laurie Lemon is the first of those when doctors were able to track that a mutated gene directly affects the function of nerve endings. The details of this mechanism remain unclear.
Inga Kaisina