Reader response

Myron Yaster MD

From Matthias Koenig, Children’s Hospital of the King’s Daughters

Interesting write up on the blog and I would agree that we are not always very rational in the way we use or misuse sugammadex.

However, with regard to the savings potential mentioned in the blogs, I have some doubts that those numbers are realistic:

1. 10.000 uses of rocuronium: I work at a freestanding pediatric hospital where we do around 14.000 anesthetics per year. Of those no more than 10% will receive rocuronium or other relaxants. So in an age of widespread LMA use and relaxant-free intubation I'm not sure that the premise of 10.000 rocuronium uses is at all realistic for any institution.

2. Sugammadex cost: I actually just had a chat with our OR pharmacist and he feels that the assumed cost of $110 per 200mg is likely on the high side given the convoluted reality of all available rebate programs depending on the patient’s insurance. 

3. Breaking sugammadex into smaller aliquots: apparently, the US Pharmacopeia just released a revised chapter 797 rule on compounding in November 2023 which would make this even more challenging and costly for hospital pharmacies than it was before. In our case, for about 1.500 doses this would likely not be worth the effort.

Just my 2 cents

From Rebecca Lee, MD on nitrous oxide

I really enjoyed your PAAD today (along with many others) and the opinion that we should stop using nitrous for inductions specifically written out instead of subtle hints. I work in a large academic institution where using nitrous for peds and adults is like water. I am the only one that stopped using it for inductions.  When I joined about 9(?) ago, I was one of the two attgs that really disliked nitrous. I eliminated nitrous from my maintenance phase as a late ca1 due to a bad experience with diffusion hypoxia and concerns of ponv. I still used it for inductions as a peds anes fellow but stopped about 5 years ago. I actually stopped for other reasons. In my deep dive of fertility and anesthesiology providers, I found nitrous was the one agent that might have increased miscarriage risk and possibly contributed to decreased fertility. After experiencing an early miscarriage after a long expensive fertility road, all I could think about was the fact that my residents somehow can’t keep a good seal during induction. And nitrous and sevo would be blowing into my face along with any female colleagues and OR personnel. 

I now have two main approaches. For calm children I start with just oxygen to have my residents hold a good mask seal and slowly titrate sevo up. Most of the time it works well and by the time the smell of 8% sevo hits them, they are “asleep” enough to not care. For the kids that are already crying etc as we mainly rely on parental presence, I will just start with 8% sevo with 100% oxygen. I’ve been doing inductions this way for the last 5 years and don’t really notice a difference in speed. (There’s too many factors involved - no premeds, poor seal, kids pulling mask off face, older kids holding their breath etc). 

We just shut off wall source nitrous and no matter how many times you go over checking tanks and turning them on/off, the residents don’t do it. Even if I go over the state tank nitrous is in and that they need to ensure tank is truly full before starting or they to contact anes tech to change it, it doesn’t happen. So I’m going to guess that by eliminating wall source nitrous, it will force a lot of providers to eliminate regular nitrous use.  

Happy New Year! I just wanted to side strongly with Dr. Gordon.  For at least 25 years I would go to Mexico with Mercy Outreach Surgical Teams and was struck that since we didn't have nitrous available, we had to use straight Sevo.  I saw no difference in the quality or speed of induction.  One benefit of doing inductions in Mexico is that some of the vaporizers were not well calibrated and would sometimes deliver up to 12 % Sevo.  Wow, what quick inductions!  Of course you had to be selective and pay very close attention to vitals on induction, but it was way safer than the old bradycardia/hypotension we would get with Halothane.  When I returned to the US, I changed my practice and began using pure Sevo inductions.  In addition, I would always lecture the residents about the dangers of N2O exposure, especially for females in the room who might be pregnant.  I'm not sure this is still a worry, but at the time, it was one of the few associations that suggested an effect on the pregnant woman  and her fetus.

Hope you and your family have a great 2024.  And keep up the good work.

Alex

From Alexander Rodarte, M.D

I just wanted to side strongly with Dr. Gordon.  For at least 25 years, I would go to Mexico with Mercy Outreach Surgical Teams and was struck that since we didn't have nitrous available, we had to use straight Sevo.  I saw no difference in the quality or speed of induction.  One benefit of doing inductions in Mexico is that some of the vaporizers were not well calibrated and would sometimes deliver up to 12 % Sevo.  Wow, what quick inductions!  Of course you had to be selective and pay very close attention to vitals on induction, but it was way safer than the old bradycardia/hypotension we would get with Halothane.  When I returned to the US, I changed my practice and began using pure Sevo inductions.  In addition, I would always lecture the residents about the dangers of N2O exposure, especially for females in the room who might be pregnant.  I'm not sure this is still a worry, but at the time, it was one of the few associations that suggested an effect on the pregnant woman  and her fetus.

Hope you and your family have a great 2024.  And keep up the good work.

PS from Myron: Most of you reading this are wondering: “a sevoflurane vaporizer that can deliver 12%, Why?” A bit of history is required. Halothane was incredible vapor anesthetic, rapid on- and off-set, sweet, non-irritating smell, cheap, enabled one breath inductions that most of you have never used because it is too dangerous. Despite the risks, halothane was the go to vapor general anesthetic in worldwide pediatric anesthesia practice. It’s MAC was about 0.74 percent and its vaporizer maxed out at 5%. Thus, when cranked up to the max, one could deliver almost 4+ MAC equivalents. Not surprisingly, once consciousness was lost, the vaporizer had to be rapidly turned down….if not hypotension and cardiac arrest was almost inevitable. And this occurred with some regularity. When sevoflurane was introduced, the original vaporizers were designed to provide the equivalent to halothane vaporizer or 12 (and even 15) % and these were the vaporizers that Alex found in Mexico. (remember the MAC of sevoflurane is about 2.2%, so if you cranked up the sevoflurane to the max and delivered 12% sevoflurane you were providing 4+ MAC equivalents). However, if you did this with sevoflurane you also produced hypotension and cardiac arrests.

In order to differentiate sevoflurane from halothane, the manufacturers of sevoflurane threw out the 12% vaporizers and rebuilt them to max out at 8%. A much lower depth of anesthesia but much safer. Sevoflurane became “safer” and because of other problems with halothane like hepatitis, replaced it in the market place. “Less filling tastes great”