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I’m going to tag this as a little tutorial for @MichaelYeadon3 who keeps saying that there’s no problem from the suppliers of medical ‘gasses’
Most hospitals in the U.K. run their O2 supply from a Vacuum Insulated Evaporator (VIE)
https://www.frca.co.uk/article.aspx?articleid=100342
1/n https://twitter.com/shaunlintern/status/1347166201064075264
Most hospitals in the U.K. run their O2 supply from a Vacuum Insulated Evaporator (VIE)
https://www.frca.co.uk/article.aspx?articleid=100342
1/n https://twitter.com/shaunlintern/status/1347166201064075264
This VIE is essentially a large thermos flask/ vacuum insulated cylinder at -180C
O2 is supplied from (typically) BOC in liquid form; when required, allowed to evaporate into gas, & supplied to hospital outlets.
Most hospitals have a VIE big enough to meet their needs
2/n
O2 is supplied from (typically) BOC in liquid form; when required, allowed to evaporate into gas, & supplied to hospital outlets.
Most hospitals have a VIE big enough to meet their needs
2/n
The problem is the pipes
Most ~12 bed ICUs have pipes that allow ~400L/min flow
This is Ok because most ventilators don’t use >20l/min; giving useful buffer capacity
Modern non invasive ventilation systems- CPAP, NIV, and High flow nasal Oxygen (HFNO), however, need more
3/n
Most ~12 bed ICUs have pipes that allow ~400L/min flow
This is Ok because most ventilators don’t use >20l/min; giving useful buffer capacity
Modern non invasive ventilation systems- CPAP, NIV, and High flow nasal Oxygen (HFNO), however, need more
3/n
A typical patient on HFNO will have 60-80Lmin flow. If they’re on 90% O2, that’s 60L O2 for 1 patient
6 of these patients will come very close to triggering the O2 flow alarm for this 12 bed unit.
4/n
6 of these patients will come very close to triggering the O2 flow alarm for this 12 bed unit.
4/n
Aside from breaking walls and re engineering the O2 supply for the whole hospital there’s no easy way of solving this problem
5/n
5/n
The next question being asked is ‘can’t we use ‘oxygen bottles’
A typical F cylinder has 1360 litres Oxygen. And weighs 18KG.
That will last ~22 minutes for a patient on HFNO
That’s 72 cylinders per patient per day.
That’s not how you can run a service.
6/n
A typical F cylinder has 1360 litres Oxygen. And weighs 18KG.
That will last ~22 minutes for a patient on HFNO
That’s 72 cylinders per patient per day.
That’s not how you can run a service.
6/n
Then you come to cost.
These 72 cylinders cost approx £2000. That’s ~20x more than liquid O2 in a VIE.
Typical ICU tariff for a L2 patient is <£1500!
7/n
These 72 cylinders cost approx £2000. That’s ~20x more than liquid O2 in a VIE.
Typical ICU tariff for a L2 patient is <£1500!
7/n
many hospitals (including mine) have had to plan around O2 supply (flow) and scatter patients- this leads to inefficiencies of dispersal if you have say 3-4 areas with 6-8 patients in them rather than one area with 30
Leads to problems with staffing and cover for safety
8/n
Leads to problems with staffing and cover for safety
8/n
So what I’ve tried to explain is that when hospitals report they’re running out of O2, the problem doesn’t lie with suppliers of liquid O2. Don’t ask them if there’s a shortage.
The problem is infrastructure and old estate.
Please stop this misinformation.
9/n
The problem is infrastructure and old estate.
Please stop this misinformation.
9/n
TLDR: there isn’t a problem with O2 supply from manufacturers. It’s a problem with old estate and infrastructure in the hospital buildings
10/10
10/10
