Now they'll sleep
Even under the knife, I was emitting f-gases...
Hi Folks,
Shorter one this week as I’m slowly recovering from surgery.
You may recall a few posts back, I talked about where you can find f-gases and refrigerant in medical imaging equipment. The inspiration came from going through a recent diagnosis. I had time to think about the article while wrapped inside a hulking MRI machine.
Well, the tumour they found, has this week been removed from my knee…
While preparing for the surgery, I began looking for other potential sources of f-gases that I could use for my regular #wherethefgashides section. One that I hadn’t counted on, was the anaesthetics.
Desflurane
It came about as I was going through an ‘Impact Assessment’ for the raft of proposed changes to the EU F-gas regulations. I was curious to find a section on inhalation anaesthetics.
I was familiar with the use of f-gases in other medical applications such as asthma inhalers for example, but their surgery use was a new area.
As it happens, fluorinated ethers are regularly used as inhalation anaesthetics during operations, both in human and veterinary medicine.
They are very effective at knocking you out. They are also potent greenhouse gases.
There are three f-gases commonly used as anaesthetics in Europe. One of the most common is Desflurane with a high GWP of 2590 (two and a half thousand times higher than CO2). There is Isoflurane (GWP 539), which used to be popular but also happens to be an ozone depleting f-gas... Then we have Sevoflurane with a more reasonable GWP of 195.
The week before surgery I had an appointment with the Anaethesist. Armed with this information I asked him which of the three he might be using on me? He looked a little surprised at the question and was non-committal in his answer. He suggested it would be determined by what stock availability he had on the day…
As it turns out, I was hooked up with the highest-GWP f-gas of the lot during my surgery – Desflurane (also known as Suprane in the US).
For the duration of my surgery I became an emissive source of f-gases. The anesthetic I inhaled, did its duty, and was then exhaled and ejected outside the building as waste gas. Where it has since gone on to do its heat trapping work.
The questionable thing for me, based on what I’ve since read, is that Desflurane is not specifically required. Sevoflurane with a GWP 10x times lower is equally effective, but price (and perhaps familiarity) amount to Desflurane still being commonly used.
There is also equipment available to capture the exhaled f-gas and recycle it. But these systems are rarely used, and I don’t believe they were present in my operating theatre.
The global impact of anaesthetic f-gases released to atmosphere is not insignificant. By some estimates it equates to the emissions from 1 million cars each year, with suggestions this is well on the low side.
While the energy sector dominates the journey to net zero, the remainder of emissions work will include lots of smaller efforts in other areas. Just like the one with f-gas anaesthetics.
There are some hospitals and doctors taking efforts, and just last month Scotland became one of the first to act. The EU f-gas regulations are also looking to limit anaesthetic use to those with a GWP below 550 in the near future.
While my knee seems to be coming good, I’m somewhat annoyed I didn’t do more to influence the anaesthetic choice. There is good reason to leave these decisions to the medical staff, but it also appears that many are not aware of the environmental impacts. I would have been happier to pay more for a low-GWP anesthetic offered the choice.
After the operation I recall gradually coming back to consciousness. The nurse kindly called my wife and told her all was fine. The next thought that entered my blurry head was another topic about refrigerants. Perhaps all that f-gas circulating inside me did carry other side effects…
Right, that’s all for this week and ‘till next time
Adrian
p.s. In case you missed it. Last week I did my regular ‘Rewind’ edition providing a summary of all recent editions. If you’re looking for a quick way to get up to speed go check it out
Fixed stuff here for newcomers
There is lots of news every week from the cooling industry and plenty of newsletters that cover it well. The intention is to keep this newsletter focused on the most prominent f-gases (fluorinated greenhouse gases), the most common of which are refrigerants and importantly their environmental impact. That’s the lane I’ve chosen - I’ll do my best to stick to it.
The What
Below are the seven formal greenhouse gases that countries and companies should track, report and hopefully reduce.
Carbon Dioxide (CO2)
Methane (CH4)
Nitrous Oxide (N2O)
Hydrofluorocarbons (HFCs)
Perfluorocarbons (PFCs)
Sulphur Hexafluoride (SF6)
Nitrogen trifluoride (NF3)
Plus the still circulating, ozone damaging chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), and the ‘new-generation’ hydrofluoroolefins (HFOs).
Hopefully you can spot the pattern.
The Why
Emissions from f-gases and refrigerants have been the fastest growing greenhouse gases over the past decade (more than CO2 and methane - check out IPCC WG3 summary for policy makers). They are also classed as super pollutants given their outsized global warming and other environmental impacts.
You can find my basic primer here and a plenty more detail in the whitepaper here
Some useful permalinks
The scale of the climate challenge can often feel daunting. This piece helps me take a step back and understand where we need to focus first - recommend a read.
There are plenty of technology solutions available to address the cooling and refrigerant challenge. You can find many of them here
Beware when the same entities who have contributed to the current f-gas problem propose you new solutions… This is a good place to get up to speed.