OXYGEN MANUFACTURING AND STORAGE ,PREPERATION AND USES AND TOXICITY

1. Oxygen
Manufacturing,
Storage,Supply,Therapy and Toxicity
by –pawan kumr rai
JR Anaesthesiology
DR.RMLIMS LUCKNOW

2. How Oxygen is produced?
• Fractional Distillation/ Cryogenic Separation
• Physical Separation
Pressure swing absorption,
Membrane filter technology and
Electrolysis.

3. Cryogenic Separation
• Carl Von Linde in 1895
• The idea behind the process is to
lower the temperature of the air such
that nitrogen and oxygen separate
based on their boiling points.
• If higher purity oxygen or liquid
oxygen is required, further
distillation is required.

4. Pressure swing adsorption(PSA) /
Molecular Sieve
• PSA devices take atmospheric air into a pressurized tank.
• Inside the tank are zeolites.

5. Storage
• Units of Pressure:
1 atmosphere = 14.7 psi
760 mmHg
1030 cm H20
1000 mbar
100 KPa

9. RsCr 220
9
Bulk Oxygen Systems
(high pressure system)
• Large capacity
• Liquid oxygen
• Small capacity (or back up)
Cylinders of different sizes
A-J , A is the smallest size and J is the largest size
D,E,H :Used most commonly in hospital settings

11. Components of cylinder
• Consists of:
– Body
– Valve
– Port
– Stem
– Pressure relief devices
Body
•MRI compatible cylinders are made of aluminium
• Modern cylinders are made of alloy of MOLYBDENUM +
STEEL +/- CHROMIUM
It is used to increase strength and to minimise weight and
wall thickness

12. Port: It is the point of exit for the gas .
Pressure Relief Devices:
– Every cylinder is fitted with pressure relief devices whose purpose is to vent the
cylinder’s contents to the atmosphere , if the pressure of enclosed gas increases to
dangerous levels
– Types: • Rupture Disc
• Fusible Plug
• Combination of Both
• Pressure Relief valve (spring loaded)
Cylinder valves are of 2 types
–packed type and diaphragm type

14. • In order to ensure that the correct cylinder is attached to
the appropriate hanger yoke of the anesthesia
machine/workstation.
A series of pins on the hanger yoke is made to fit into the
corresponding indentations(pits/holes) drilled into
cylinder valve
• Holes are positioned in an arc below the outlet port
•The pins are 4.75mm in diameter and 6mm long except
for pin number 7 which is slightly thicker and placed at
the centre (between port 3 and 4)
Pin Index Safety System

16. RsCr 220
Diameter Index Safety System (DISS)
• Safety Systems
• DISS use noninterchange-able,
threaded fittings to connect gas-
powered devices to station outlets
50 P.S.I (INTERMEDIATE PRESSURE SYSTEM)

17. RsCr 220
Oxygen cylinder Markings

18. •Periodic visual inspection for any distortion, cracks, dents, leaks, etc.
•Tensile test on 1 out of every 100 cylinders manufactured. Strips of the
cylinder are cut and stretched.
•Flattening test, Bend test and impact test are carried out on at least one in
every 100 cylinders
•Hydraulic test—the cylinder is tested to 1.66 times it service pressure.
This helps detect any leaks and to determine the retention of structural
strength. A cylinder must be subjected to internal hydrostatic pressure
testing at least every 5 years.
TESTING OF CYLINDER

19. • Factors for determination of duration
• “E” cylinder = 0.28
• “H” cylinder = 3.14
Duration of flow = Pressure x Cylinder factor
Flow
Liquid system - factor :860
Content=Amount of gas in liquid = Weight of liquid x 860
2.5
Duration of flow = Contents
Flow

20. What precautions should be taken while
transporting a cylinder?
ƒ
 Upright position ƒ, Wear protective footwear/safety gloves
 ƒDo not lift by protective cap/guard as you may damage valve ƒ
 Ensure all cylinders are properly labeled as to the contents ƒ
Do not subject cylinders to temperature extremes.
ƒ
ƒ

21. Cylinders should be handled only by trained person
Cylinder valves, regulator,Gauges, and fitting should never come into contact of oils , greases ,
organic lubricants etc .
Cylinders should not be subjected to extreme of temperatures .
Connection to piping , regulator, and other equipments should always be kept tight to prevent
leakage.
No part of the cylinders should be tainted , painted or modified by users .
A cylinder should never come into contact of electricity .
Before use ,cylinder should be identified by the label.
The color of the cylinder should not be relied upon for identification .
RULES FOR SAFE USE OF CYLINDERS

22. Only DOT or ICC approved cylinder should be used .
A pressure regulator should always be used before any fitting is applied to cylinder valve
, the valve should be opened slowly and briefly to remove dust or any other
particle ( cracking) .
A sealing washer or gasket in good condition should always be used with small cylinder
valve .
 If more than one seal is used the pin on yoke may not extrude far enough to engage
mating whole or safety pin index.
A cylinder valve should be opened slowly ,because if gases passes quickly into the space
between valve and the yoke or the regulator , the rapid recompression in this space will
generate large amount of heat ,because there is no space for dissipation of heat , this
constitutes an adiabatic process. Particle of dust, grease, etc present in that space may be
ignited by the heat causing a flash fire or explosion.
Do not drag slide or roll- use cylinder cart

23. Cylinder Manifold System
Intermediate
pressure system
High pressure
system

25. One of the most serious mishaps that occurred was depletion of the oxygen supply.
The result was delivery of 100% anesthetic gas.
Numerous inventions have been devised to prevent this-
• Oxygen failure
safety device.1.
• Oxygen failure
supply alarm.2.
Oxygen pressure failure devices

27. Operates in a threshold manner: either open or shut.
Pressure Sensor Shut-off Valve:
 Oxygen pressure moves the piston and pin upward and the valve opens for N2O
When pressure of oxygen falls below preset value, force of the valve return spring completely closes the valve

28. Based on a proportioning principle rather than a threshold principle. Pressure
of N2O falls in Propotion of decrease of Oxygen.
Total cutoff seen at <12 psig.
Seat nozzel assembly connected to a spring loaded conical tapered piston.
Oxygen Failure Protection Device

31. The oxygen flush receives oxygen from the pipeline inlet or cylinder pressure
regulator and directs a high unmetered flow directly to the common gas outlet.
It is commonly labeled “02+.”
It can be activated regardless of whether the master switch is turned ON or OFF.
A flow between 35 and 75 L/minute must be delivered.
Oxygen flush
“Single purpose, self closing device & recessed”

32. BALL AND SPRING
VALVE

33. Mechanical device : Link 25 system
Pneumatic device : Oxygen Ratio Monitor Controller (ORMC)
Electronically controlled : Penlon Ltd
ANTI HYPOXIA DEVICES
Mechanical Linking of O2 & N2O.
O2 – 14 tooth sprocket, & N2O – 29 tooth sprocket,
connected by metal chain.
• Both knobs turn together – to maintain min 25%
O2 conc.
 • Disadvantage – if 3rd gas is administered (eg
He,air) – hypoxic mixture may be delivered.
Mechanical device : Link 25 system

34. • Mandatory Min O2 Flow (MMOF):- A MMOF – 50-250 ml/min – must as
soon as the master switch is turned on.
•O2 flow – cant be reduced below that.
• Min O2 Ratio :- ASTM Stds require that; A Min O2 conc of 21% in the
FGF at common gas outlet.

35. • Pressure is reduced to a 50 psi working pressure in the patient’s
room where it can be used to operate respiratory equipment.
• Provide connections for gas-delivery devices such as flowmeters and
mechanical ventilators.
Station outlet

36. Therapy
•Oxygen is also like a drug.
• It must be used meticulously & deligently.
• If abused it can cause complications.
•
FATHER OF MODERN
O2 THERAPY
J S HALDANE

38. INDICATIONS FOR O2 THERAPY
1.Hypoxia – when PaO2 comes down to 60mmhg, like low cardiac output
states,M.I,anemia,hemodilution,CO poisoning,acute hypermetabolic states.
2.Trapped gases – like obstruction.
3.Special situations – like anesthesia.

39. Indications of hyperbaric oxygen therapy
Poisoning: CO
Infections: clostridium myonecrosis
Acute ischaemia:crush injury
Chronic ischaemia: radiation necrosis
Ischaemic ulcers: diabetic ulcers

40. 1.Nasal catheters.
8-14 G ,passed through into oropharynx.
Reservoir of O2 builds up in pharynx.
O2 DELIVERY SYSTEMS:
1.Low flow or variable performance systems.
2.High flow fixed performance systems.
LOW FLOW SYSTEMS:
O2 Flowrate (L/min) FIO2
1 0.24
2 0.28
3 0.32
4 0.36
5 0.40
6 0.44
Demerits • Mucosal irritation (uncomfortable) • Gastric dilatation (especially with high flows)

41. 2.Nasal prongs:
-The prongs protrude 1cm into nares.
-Well tolerated.
-Useless in mouth breathers.
-No reservoir system.
3.Simple O2 masks:
- Covers the nose & mouth.
-4-6 lits/min.
O2 Flowrate (L/min) FIO2
5-6 0.40
6-7 0.50
7-8 0.60

42. 4.Mask with reservoir bags:
-High FiO2 with 5-6 lits of O2.

43. 1.VENTURI MASKS:
- Works on Bernoulli principle.
- Can deliver O2 at accurate concs.
HIGH FLOW SYSTEMS:
- Total flow is high with or without entrainment

44. 3. O2 tent:
-Used in pediatric practise.
-10-12 lits/min.
-Fire accidents.
2. O2 hood:
-Used in bed bound infants not intubated.
-Made of plexi glass.
-Humidified O2, 3 times M.V.
4.JET VENTILATION:
- High frequency oscillation.

45. Drying of
mucus
membrane
Depression of
ventilation in
COPD
Atelectasis due
to absorption
collapse
O2 toxicity
HAZARDS OF O2 THERAPY

46. OXYGEN TOXICITY
• Increase in oxygen concentration leads to free radical formation
• Reacts with cellular DNA proteins, lipids and membrane.
1.Pulmonary oxygen toxicity
(LorrainSmith effect)
3.C.N.S O2 toxicity (Paul-Bert effect)
2.Retrolental fibroplasia

47. 1.Pulmonary oxygen toxicity (LorrainSmith effect):
Symptoms: substernal pain,
irresistable cough,
dyspnoea,V.C dec.,
compliance dec.,
pulmonary interstitial edema leading to fibrosis.
Safe dose of oxygen
100%O2 given not more than12 hours
-80% O2 for not more than 24hrs.
- 60%O2 not more than 36hrs.

48. 2.Retrolental fibroplasia –
Occurs when PaO2 is more than 80mmhg for more than 3 hrs in new born.
Very premature babies are more susceptible. - O2 saturation must be around 90-92 %.
3.C.N.S O2 toxicity (Paul-Bert effect): -
Seizures or convulsions
Depressed ventilatory drive
Coma
Brain death and eventually death

50. Take home message
No drug is more important than oxygen.
Medical oxygen is of high purity >99.5%, manufacturing of oxygen by fractional
distillation and PSA techniques give us O2 of >99.5% purity.
Cylinders has various specifications marked over it, must be checked before.
Medical gas supply system has 3 different pneumatic zones, having various safety
features.
Oxygen is like a drug, life saving when used meticulously otherwise toxic.
SAFE DOSE- 100% not>12hrs, 80%not>24hrs, 60%not>36hrs.

52. THANKS THANK YOU

56. Defintions
Psi: Pounds per square inch
Psig: Pounds per square inch gauge
GAUGE PRESSURE
It is the difference between the measured pressure and the atmospheric pressure Most gauges
are measured to read zero at atmospheric pressure
• Psia: Pounds per square inch absolute
ABSOLUTE PRESSURE It is based on reference point of zero in a perfect vacuum Psia = Psig
+ atmospheric pressure Eg: at sea level- atmospheric pressure is 0 but psia is 14.7psia
•Critical temperature: – It is defined as the temperature below which no gas can be liquefied
irrespective of which pressure is applied
• Critical Pressure: – Defined as the minimum pressure required to liquefy a gas at its critical
temperature