Carcinoid tumors are odd birds. They are of a group of cells in your body that are known as the neuroendocrine system. Neuroendocrine cells receive some sort of signal from your nervous signal and, in response, they release some sort of hormone into your blood system. Those hormones then stimulate another part of your body to perform some task.
For example, if someone sneaks up behind you in the parking lot and screams loudly, your adrenaline gland releases a huge amount of adrenaline into your blood stream, enabling the fight or flight mechanism. Insulin is another example. If you consume a large amount of sugar, your pancreas releases insulin to bring help bring the level of sugar down in your blood to a manageable level.
The neuroendocrine cells from which carcinoid tumors grow are cells that generate serotonin. Serotonin serves several purposes in body but one of the primary jobs is to regulate intestinal movements. The tumors don't forget their previous life as neuroendocrine cells but now there are a much greater number of these cells. What that means is that they still attempt to respond to the signals to regulate intestinal movements.
This results in things getting out of balance. The tumors will get the signal that food has entered the digestive tract and then decide to start telling the rest of the digestive tract to begin processing the food. Normally, this is just fine but with all the extra cells, way too much serotonin gets released and the digestive system goes into overdrive, leading to, often, explosive diarrhea.
In the same vein, kallikrene (yet another hormone but an odd one) is released at times which lead to the blood vessels increasing in size. This affect people notice is that the face and chest will often turn quite red and there is often a feeling of light-headedness that accompanies this along with a drop in blood pressure. I can usually cause this to happen by walking up 5 flights of stairs and then watch my face turn red 45 seconds after reaching the 5th floor.
Carcinoid crisis is when this happens to the extreme and it usually happens at one of the single most scary times possible. General anesthesia is the most complicated portion of a surgery and it is one of the single biggest causes of carcinoid crisis. Under general anesthesia, my entire upper body will turn almost purple, my heart rate drops and my blood pressure hits the floor.
I typically have a fairly low blood pressure (~110/75) but the last time crisis occurred during surgery, I dropped to 75/40 and lower. Heart rate (usually around 65 for me) dropped into the 40s and I was standing at the precipice of death. For this reason, I always try to avoid general anesthesia for any procedures and it appears that low levels of propofol are usually sufficient for the procedures that I have been receiving lately.
Sometime, I will need general anesthesia and we have a plan for that as well. Sandostatin is a drug that seems to inhibit carcinoid syndrome and is generally given in small doses. Whenever I do need a major surgery, I will be admitted the night before and then put on a continual high-dose drip of sandostatin. Just prior to anesthesia being given, I will receive another bolus shot of sandostatin and then the drip will continue throughout the procedure. This worked for me in my second major surgery of 2012 and, if I have to go under again, we hope it will work again.
If I still go into crisis, the key is to then just start giving massive doses of sandostatin and hang with me because I have always come out of it. It takes as long as an hour but as long as my heart continues to pump, I will survive the crisis because the body will simply run out of kallikrene. Whenever I do go in for procedures, even with propofol, I still try my best to scare the anesthesiologist as much as possible and ensure that they have sufficient sandostatin ON HAND in the operating room.
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