Over the years I have had several procedures that have required anesthesia. On some of the dental work I have required up to three shots before I was able to go on with the dental work. I had surgery to repair a hernia and while I was under, I was in a lot of pain and could hear the doctor and nurses during the procedure. I was unable to verbalize that I was in pain and luckily the doctor noticed something was wrong and directed the anesthesiologist to administer more anesthesia. On a second surgery, I informed the doctor that I had had previous problems with anesthesia, and he said that they would administer a higher dose. I did not feel anything during that surgery, but was informed by the doctor that my heart rate dropped down to 20 beats per minute and they had a hard time reviving me. On one of your answers to anesthesia resistance you mentioned that the use of capsaicin in conjunction with anesthesia sometimes works. Throughout my life I have included jalapenos, habaneros, serranos and other very hot spices in my diet. Could this be the reason for me developing anesthesia resistance?
In short, no. Capsaicin acts at the molecular level on certain receptors types that interact with local anesthetics, but should not you less susceptible to anesthesia. Every individual has a different genetic make up and there are some genes that result in a the person requiring a higher dose than usual.
The heart rate drop could be from a vagal response to the surgery itself (neurologic response) which is common with certain types of procedures, or a reaction the high doses of narcotic (opioid based) pain medications which are used during anesthesia. This is usually easily treated with an anticholinergic medication that counter acts the slow heart rate.
Oh, in my previous post, I postulated that capsaicin could be a future therapeutic option but further investigation is ongoing in its use in conjunction with local anesthetics.