Welcome to my channel, Medicosis Perfectionalis. In the previous videos, we talked about methemoglobinemia, how to diagnose it, how to treat it, mnemonic about it. Today, let's turn our attention to cyanide poisoning, the story of Rasputin. So, let's get started. And let me remind you to watch my previous video first.
Let's start with some words of wisdom. A comprehensive education is a well-stocked pharmacy, but we have no assurance that potassium cyanide will not be administered for a head cold. In 2013, at a Brazilian nightclub called Kiss in Santa Maria, a huge fire erupted, causing death of 156 people.
What's the cause? Cyanide poisoning. And here is another tragic story from the last century.
I'll leave you to read it. And another one. Cyanide can be used to commit suicide, which is a permanent solution for a temporary problem, an answer to nothing.
While his enemies were trying to poison him, Grigory Rasputin ate from the cake and drank from the wine, both of which had enough amount of... potassium cyanide to kill several men. Yet, he survived. How can a man ingest potassium cyanide and survive?
I'll tell you later. This is not a mythical story from Arabian night. It's a true story from Russia. Cyanide could be present in the three forms of matter, gas, liquid, and solid. Cyanide poisoning can occur by inhalation, ingestion, or skin absorption.
When cyanide touches your skin for a long time, it can poison you. So causes of cyanide poisoning. The most common cause in the United States is smoke inhalation. So if you are like having an exam in the medical boards and they want to test you about cyanide, the vignette will ask you about, yes, a firefighter or a person who was on fire, which makes perfect sense. Suicidal ingestion.
Some medications such as sodium nitroprusside. Industrial exposure. And some foam bubble wrap and some... like the wrap that you use to wrap furniture or whatever that contains polyurethane can contain cyanide. Let's talk physiology first.
Here is your normal electron transport chain. You keep pumping protons like this to the intermembrane space, pumping protons, pumping protons, and then protons will accumulate here, and they will push the final proton inside, converting ADP into ATP. Boom, you have energy in the matrix.
Fine. We have complexes that keep shifting the electrons between them, like this. We have complex 1, 2, 3, 4, and 5. What we care about here is complex 4. There is an enzyme before complex 4, but it's also included within complex 4 called cytochrome C oxidase.
It's here. And here is complex 4 containing cytochrome A and cytochrome A3. Don't ever forget this.
They form water. This cytochrome C oxidase contains iron. What type of iron?
Is it ferrous or ferric? The answer, it's ferric. And here is a slide to remember forever. Cyanide loves binding to Fe3. Therefore, cyanide will either bind to Fe3 in your methemoglobin or it will bind to the Fe3 in the cytochrome C oxidase in the electron transport chain in your mitochondria.
It's either gonna bind to this or this. No question. So let's say that you are lucky, kind of lucky, and you have methemoglobin, which contains the Fe3 plus iron. Now cyanide can bind to methemoglobin, forming cyanomethemoglobin, because methemoglobin contains the ferric that the cyanide loves.
And by sodium thiosulfate, there is cyanide, they go into urine, go to hell cyanide, we don't need you. However, the mitochondria is unaffected. The cytochrome C oxidase has been rescued.
Nobody's gonna touch this ferric. Why? Because cyanide is busy meeting with the ferric of the methemoglobin, thankfully. Repetition is the mother of pedagogy.
Cyanide loves binding to ferric. Cyanide will either bind to ferric in the methemoglobin or will bind to the ferric in the cytochrome C oxidase. However, when you're very unfortunate and you don't have any methemoglobin, so there is no ferric for the cyanide to bind, cyanide is gonna bind instead to the ferric in the cytochrome c oxidase called enzyme inhibition Now this enzyme is gone.
The complex IV is gone. Do you think you'll be able to produce ATP in this case? Nah, never. That's why cyanide is a poison. It's a cellular respiration poison.
For the bazillion time, cyanide loves binding to ferric. Cyanide will either bind the ferric in the methemoglobin, or if you're unfortunate, it will bind to the ferric in the cytochrome C oxidase. So cyanide... poisoning cyanide binds the fe3 the ferric and the cytochrome oxidase inhibition of complex 4 leading to no atp formation when your mitochondria cannot utilize oxygen because oxygen is used in the last step okay or not the last step one of the steps of the electron transport chain it's called an electron acceptor so if oxygen cannot accept electrons the mitochondria cannot utilize oxygen guess what your source of ATP gonna be? Yes, the dreaded anaerobic glycolysis, which leads to lactic acidosis, which leads to metabolic acidosis.
High anion gap or normal anion gap? High anion gap metabolic acidosis. Amygdalin, which is found in some apricot and some almond.
By hydrolysis can give you? Yes, hydrogen cyanide. One apple a day, keep the doctor away.
Lots of apricots a day. Mitochondria has gone astray. Some natural alternative medicine gurus will try to sell you some drugs online that contain cyanide. They claim these drugs cure cancer. This is nonsense.
Don't forget, anecdote is not evidence. If anybody tells you, I had a cousin, and this cousin had cancer, we gave him cyanide, and now he's cured. Even if this is true, which is not, this is anecdote.
This is not data. For something to be scientific, it has to be tried on many, many, many people to make sure it works. It works on the random sample of the population, and now we can use it as a drug.
But just because it's online doesn't make it cool. Don't ever forget that. And don't listen to your broke brother-in-law with an opinion.
Some doctors or lab technicians or pharmacists may try to put an end to their life using cyanide because they have access to it. So it's a... Good idea for a question on your exam. They will have a pharmacist who is trying to do whatever, and now he presents with all the symptoms of cyanide poisoning. Cyanide loves binding to ferric, so cyanide will either bind the ferric and the methemoglobin, or it will bind the ferric and the cytochrome C oxidase.
Therefore, to cure cyanide poisoning, you should induce a state of methemoglobinemia to rescue the cytochrome C oxidase in your mitochondria. That's why I told you in the previous videos, in my words of wisdom, everything in life has its pros and cons. Methemoglobin has cons, yes, it's a disease, but it has pros. It can cure cyanide poisoning.
That's why the famous Roman physician Galen said, the best physician is also a philosopher. Of course, he was talking about me. For the few guys that support me on Patreon, you guys are the best.
If you'd like to make this channel bigger and better, please go to patreon.com forward slash medicosis join the movement thank you for watching until next time be safe stay happy and study hard