Blue blood: the anesthetic caused an unusual symptom

About a rare case report said doctors at a hospital in Rhode island in the "Medical journal in New England". They asked the woman complaining of weakness. When examination revealed cyanosis — bluish color of the skin and nails. But unusual was the fact that the patient's blood was dark blue.

the Doctor the emergency Department Otis Warren (Otis Warren) had determined that the woman has a rare disorder called "methemoglobinemia". Hemoglobin that transfers blood cells oxygen is converted into methemoglobin, a molecule of which has a different degree of oxidation of the iron atom. Methemoglobin are also capable of binding oxygen, but it disrupted the function of transfer oxygen to the tissues of the body. Normally the methemoglobin is found less than 1 % of erythrocytes.

the patient's Blood was dark blue. Photo: New England Journal of Medicine

in milder forms of methemohlobinemia (level of methemoglobin greater than 10 %) are dyspnea, cyanosis, intolerance to physical exertion, headache, fatigue, dizziness and possibly loss of consciousness. If the level of methemoglobin exceeds 50 %, possible convulsions, coma, and death.

the Most well-known congenital methemoglobinemia caused by a recessive mutation. In the history of medicine came in "Blue Fugetsu" — family from Kentucky with a congenital form easy methemoglobinemia. Family members often intermarried with the family living in the neighborhood. As both families met gene methemohlobinemia, frequent were the cases when one of the family members received two copies of the gene, and the skin of these people was indeed bluish.

But was repeatedly noted cases of methemohlobinemia for poisoning by various substances, sometimes as a side effect of medication. Described cases of methemohlobinemia after an overdose of antibiotics (trimethoprim, sulphonamides and Dapsone), local anesthetics (articaine, benzocaine, prilocaine, and lidocaine), as well as the poisoning aniline dyes, metoclopramide and bismuth nitrate. The remedy in such cases is substance called methylene blue. It restores a degree of oxidation of iron in hemoglobin and returns its properties. Usually the effect occurs within several minutes after injection of methylene blue into the blood.

As it turned out, the night before, the woman from Rhode island were used for a toothache a local anesthetic containing benzocaine. However, she took too large a dose of the drug. Treatment with methylene blue was successful, and the next day the woman was discharged from hospital in good condition.