1. Dip. Software based statistics PhD ( physiology), FICA , IDRA
Anesthesia cylinders
Dr. S. Parthasarathy
MD., DA., DNB, Dip. Diab. DCA,
Dip. Software based statistics
PhD ( physiology), FICA , IDRA

2. Definition !!
Gas cylinder is a term that is commonly used to describe a pressurized container used for storage and transport.
Use ??

3. Modern cylinders are manufactured using lightweight strong chrome-molybdenum steels which, as well as conforming to stringent material standards, can be filled to pressures of up to 300 bar g.
It is made of an alloy !!
What s that ??

4. Iron approx – %

5. aluminium liner which is then strengthened by wrapping a filament material, such as Kevlar or carbon-fibre, coated in epoxy resin circumferentially along the parallel length of the cylinder.
Special cylinders made from aluminum are useful in magnetic resonance imaging (MRI) room

6. Parts Body Shoulder Neck Neck is tightened with a valve
Woods metal is the paste used which melts with to allow gas to leak
No explosion
Disc rupture is also there

7. Valve – brass or bronze

10. Routine anesthesia machine
These are fitted to large cylinders of medical oxygen, medical air, Entonox used in pipeline manifolds

11. Bull nose
F and G type = bigger ones
Pressure relief device

12. Bull nose
O ring
Fit proper
Change the O if leaks

13. Hand wheel
Large nitrous oxide cylinders for use on cylinder manifolds and carbon dioxide cylinders of size F and G are fitted with handwheel valves which are surrounded by a protective Guard and have a gas specific, male thread, side outlet.

14. Integral valves manufactured in a clean environment
eliminates the risk of incorrect
regulator attachment
Two outlets
Easier to use
Pressure gauges

15. Neck label It is marked with the gas chemical symbol, tare weight,
pressure at the last hydraulic test
serial number
Tag is different

16. Pin index safety system
There are seven hole positions on the circumference of a circle of 9/16 inch radius centered in the port.
Pins project from yolk side and holes in the cylinder
The pins are 4 mm in diameter and 6 mm long.
Assigned number for gases

17. Bodok seal

18. PIN index is there
But manual opening
of newer valves

20. Return check valve and yolk plug
Oxygen to nitrous
No flow
One cylinder is attached – no leak
Use yoke plug
Get it to the spring to avoid getting lost

21. Oxygen and air are compressed gases while nitrous is liquified
Gauge – oxygen – OK but
While using a cylinder of N2O with a continuous flow of 6 litres/minute, the cylinder pressure tends to fall mainly due to cooling of the liquid as it vaporizes and the consequent fall in vapour pressure. If the flow is interrupted for a brief period, the gauge will again read full.

22. Colour coding Due to variation in color tones, chemical
changes in paint pigments, color should not be used
as a primary means for identification of cylinders

23. Pictures taken from internet for closed academic purpose only
Sizes !!!
Pictures taken from internet for closed academic purpose only

24. Sizes according to us !! it’s A B C D !! A corresponds to E
Oxygen 2000 psi and 660 litres approx
B type 1350 litres
Bulk or D type litres
Oxygen does not come in C
CO2 cylinders for pneumoperitoneum are C type
Nitrous – A type -750 psi and 1500 litres approx

26. How much oxygen is there ??
Approximate remaining in hours =
O2 cylinder pressure in psi/200 × O2 flow rate per minute.

27. Complete filling ??
These cylinders (liquid) are not filled completely, but only up to a filling ratio
Weight of gas in a cylinder/weight of water that cylinder can hold at 60° F
The filling ratio of nitrous oxide is 0.75, but 0.67 in the tropics
But – liquids – tare weight and difference
90 % is nitrous in cylinder – that’s is different volume Vs weight

28. 100 kPa=1000mbar=760mm of Hg=1030cm of H2O=14.7psi=1atmosphere

29. Storage Not stored along with non medical cylinders
be under covered and not subjected to extremes of heat
kept dry, clean and well ventilated
good access for deliveries and a reasonably level floor
allow segregation of ‘full’ and ‘empty’ cylinders
permit separation of different gases and cylinder sizes
allow for strict stock rotation to enable cylinders with the oldest fill date to be used first

30. Storage No sources of heat or ignition nearby
Prohibiting smoking or naked lights in the vicinity
large cylinders - stored vertically in concrete pens small cylinders - horizontally in wooden or plastic racks to prevent damage to the cylinders
not allow the temperature to fall below 10°C where full Entonox cylinders are stored
No unauthorized entry

31. Safe use ?? CRACKING—reduces possibility of flash fire
A sealing washer in good condition
Open valve before bringing the apparatus to the patient.
Close Flow control valve before the cylinder valve is opened
While opening, stand to the side; not in front or back
Quick opening can generate heat  flame

32. Rules for safe use open the cylinder, check the pressure
Hissing sound= leak tightenstill leak replace washer.
Where is the leak ? soap water.
If leak in valve itself, tighten the packing nut by turning it in a clockwise direction
Even if no hissing sound, check for loss of pressure when no gas is being used
Valve should be fully open when in use- minimum three rounds !!

33. Safe use An empty should not be left on anaesthesia machine
close the valve before removing from a regulator or yoke
tag - removed when cylinder is empty
Caps to be replaced before
sending for refill

34. Valve breaks – so dangerousOK Ok
Ok but ??
Valve breaks – so dangerous

35. Remove the seal
Seal may go in the speed and block gases later
Danger

36. So many

37. Testing the cylinder by the factory !!
Must be tested at least every 5 years.
Hydraulic test
Tensile test
Flattening test
Impact test
Bend test
External and endoscopic examination

38. Flattening test
The cylinder is kept between two compression blocks and pressure is applied from both sides until the distance between blocks remains 6 times the thickness of the wall of cylinder.
The walls should not crack.
Pressure test: the cylinder is subjected to high pressures of about kPa, which is more than 50% above their normal working pressure.

39. Dangers Cylinder Transfilling
Transfilling contents from one cylinder to another should not be performed by the user
Incorrect
Cylinder
Valves
Contents
Color
No odor for gases

40. Hazards – continue Asphyxia Projectile damage Fires
Cold thermal injury
The gases and vapours should be free of water vapour when stored in cylinders.
Water vapour freezes and blocks the exit port when the temperature of the cylinder decreases on opening

41. What is the carry home message ??
Summary
Cylinders – made of what ?
Parts
Valves
Pin index
Colour coding
Sizes
Safe use
Testing
Hazards
What is the carry home message ??