Medical gases are gases used in medical procedures for treatment, anesthesia, and driving medical devices. The main gases used are oxygen, nitrogen, nitrous oxide, argon, helium, carbon dioxide, compressed air, and medical vacuum. They are delivered through specialized medical gas pipeline systems and used in areas like operating rooms and ICUs. Key purposes for the different gases include oxygen supplementation, anesthesia, pneumatic pressure, and insufflation during surgery. Safety measures like color coding and emergency shut-off valves are important components of medical gas systems.
2. DEFINITION
• Medical gases are gases used
in medical procedures
• A medical gas is defined as one that is
manufactured, packaged, and intended
for administration to a patient in
anesthesia, therapy, or diagnosis.
3. • Medical gases are considered
prescription drugs because their
use as drugs is unsafe without
the supervision of a licensed
practitioner or by properly
instructed emergency personnel.
4. • Medical gases are gases used
in medical procedures.
• Some are used for treatment, some
for anesthesia, and some for
driving medical devices and tools.
5. • There are 7 kinds
of gases commonly used:
oxygen, nitrogen, nitrous oxide,
argon, helium, carbon dioxide
and compressed air (medical air)
& medical vaccum
6. PURPOSE OF MEDICAL GAS
Medical gases are used within hospital
settings for many purposes.
Oxygen, used to provide supplemental
oxygen to the respiratory system ; in
dentistry in combination with nitrous
oxide ; and as an emergency standby.
7. • Nitrous oxide, used as an anesthetic
agent in surgery; mixed with oxygen
to help patients relax during dental
procedures; and in cryosurgery (the
use of extreme cold to destroy
tissue).
8. • Nitrogen, used to provide
pneumatic pressure in medical
equipment; to prevent combustion
and other chemical reactions; and
as a component of many gas
mixtures.
9. • Carbon dioxide, used to inflate
areas of the body for "keyhole"
surgery (small incisions made to
accommodate surgical
instruments ); mixed with air or
oxygen to stimulate breathing; and
in cryosurgery or testing tooth
sensitivity in dentistry.
10. • Medical air, used in
administering breathing
treatments and as a mixing
component for other respiratory
gases.
11. • Helium, used in breathing mixtures
for patients with impaired lung
functions.
12. WHERE MEDICAL GAS IS USED
The departments that use medical
gases in hospitals include operating
rooms, pre-communicators,
recovery rooms, debridement
rooms, obstetrics and gynecology
wards, ICU wards, and general
wards.
13. POINTS TO CONSIDER
• Medical gas systems are
commonly color coded to identify
their contents.
• Emergency shut-off valves, or zone
valves, are often installed in order
to stop gas flowing to an area in the
event of fire or substantial leak, as
well as for service.
15. Cont.......
• Valves may be positioned at the
entrance to departments, with
access provided via emergency pull-
out windows.
16. OXYGEN
Oxygen is the most basic gas for life,
and it is used medically to
supplement oxygen to oxygen-
deficient patients.
• Direct inhalation of high purity
oxygen is harmful to the human
body.
17. • Long-term use of oxygen concentration
generally does not exceed 30-40%.
Ordinary patients breathe oxygen
through oxygen flowmeter; critically ill
patients breathe oxygen through the
ventilator.
• Oxygen is also used in high-pressure
tanks to treat diving, gas poisoning, and
for drug nebulization.
18. • Oxygen may be used for patients
requiring supplemental oxygen via
mask.
• A large storage system of liquid
oxygen at the hospital which is
evaporated into a concentrated
oxygen supply, pressures are usually
around 345–380 kPa (50.0–55.1 psi)
19. • This arrangement is described as
a vacuum insulated evaporator or
bulk tank.
• In small medical centers with a low
patient capacity, oxygen is usually
supplied by a manifold of multiple
high-pressure cylinders.
20. • In areas where a bulk system or high-
pressure cylinder manifold is not
suitable, oxygen may be supplied by
an oxygen concentrator.
• However, on site production of oxygen
is still a relatively new technology.
21. NITROUS OXIDE
• Inhalation of a small amount of
nitrous oxide has an anesthetic and
analgesic effect, but a large amount
of inhalation can suffocate people.
22. • Medically, a mixture of nitrous
oxide and oxygen is used as an
anesthetic agent, and anesthesia is
inhaled by the patient through a
closed manner or a ventilator.
23. • Nitrous oxide is supplied to various
surgical suites for its anaesthetic
functions during preoperative
procedures.
• It is delivered to the hospital in
high-pressure cylinders and
supplied through the Medical Gas
system.
24. • Some bulk systems exist, but are no
longer installed due to
environmental concerns and overall
reduced consumption of nitrous
oxide. System pressures are around
345 kPa (50.0 psi), 4 bar (400 kPa;
58 psi) UK.
25. CARBON DIOXIDE
Medically, carbon dioxide is used to
inflate the abdominal cavity and
colon for laparoscopy and
colonoscopy.
• In addition, it is also used for
laboratory culture of bacteria
(anaerobic bacteria).
26. • Carbon dioxide can be made into dry
ice by applying pressure (5.2
atmospheres) and cooling (-56.6°C
below).
• Medical dry ice is used for cryotherapy
to treat cataracts and vascular
diseases.
27. Typically used for insufflation during
surgery, and also used in laser
surgeries.
• System pressures are maintained at
about 345 kPa (50.0 psi), UK 4 bar
(400 kPa; 58 psi). It is also used for
certain respiratory disorders. It
contains 5 percent.
28. ARGON, HELIUM
They are colorless, odorless,
non-toxic inert gas.
Medically used for argon gas
knife, gas knife, and other
surgical instruments.
29. NITROGEN
Nitrogen is a colorless, odorless,
non-toxic, non-flammable gas.
It is inactive at room
temperature and does not react
chemically with ordinary metals.
30. Nitrogen is used to drive
medical equipment and tools.
Liquid nitrogen is commonly
used in cryosurgery in surgery,
stomatology, gynecology, and
ophthalmology.
31. Nitrogen is typically used to
power pneumatic surgical
equipment during various
procedures, and is supplied by high-
pressure cylinders. Pressures range
around 1.2 MPa (170 psi) to various
locations.
32. MEDICAL AIR
• Medical air is compressed air supplied
by a special air compressor, through a
dryer (in order to maintain correct dew
point levels), and distributed to patient
care areas by half hard BS:EN 13348
copper pipe and also use isolation ball
valve for operating the services of
compressed air 4 bar. It is also called
medical air 4 bar.
33. • In smaller facilities, medical air may
also be supplied via high-pressure
cylinders. Pressures are maintained
around 345–380 kPa (50.0–55.1 psi).
• Compressed air is used to deliver
power to oral surgical instruments,
orthopedic instruments, and
ventilators.
34. INSTRUMENT AIR/SURGICAL AIR
Like nitrogen, instrument air is used
to power surgical equipment.
It is generated on site by an air
compressor (similar to a medical air
compressor) rather than high-
pressure cylinders
35. Early air compressors could not
offer the purity required to drive
surgical equipment.
Therefore instrument air is
becoming a popular alternative
to nitrogen.
37. As with nitrogen, pressures range
around 1.2 MPa (170 psi). UK
systems are supplied at 11 bar
(1.1 MPa; 160 psi) to the local area
and regulated down to 7–8 bar
(700–800 kPa; 100–120 psi) at point
of use.
38. MEDICAL VACUUM
Medical vacuum in a hospital
supports suction equipment and
evacuation procedures, supplied
by vacuum pump systems
exhausting to the atmosphere.
39. Vacuum will fluctuate across the
pipeline, but is generally
maintained around −75 kPa
(−560 mmHg; −22 inHg),
−450 mmHg (−60 kPa; −18 inHg)
UK.
40. WASTE ANAESTHETIC GAS
DISPOSAL/ANAESTHETIC GAS SCAVENGING
SYSTEM
Waste anaesthetic gas disposal,
or anaesthetic gas scavenging
system, is used in
hospital anaesthesia evacuation
procedures.
41. • Although it is similar to a medical
vacuum system, some building
codes require anaesthetic gases to
be scavenged separately.
• Scavenging systems do not need to
be as powerful as medical vacuum
systems, and can be maintained
around −50 to −65 kPa (−380 to
−490 mmHg; −15 to −19 inHg).
42. MEDICAL GAS MIXTURES
There are many gas mixtures
used for clinical and medical
applications. They are used for
patient diagnostics such as lung
function testing or blood gas
analysis.
43. Test gases are also used to calibrate
and maintain medical devices used
for the delivery of anaesthetic
gases.
In laboratories, culture growth
applications include controlled
aerobic or anaerobic incubator
atmospheres for biological cell
culture or tissue growth.
44. Controlled aerobic conditions are
created using mixtures rich in
oxygen and anaerobic conditions
are created using mixtures rich in
hydrogen or carbon dioxide. Supply
pressure is 4 bar (400 kPa; 58 psi).
• Two common medical gas mixtures
are entonox and heliox.
45. REFERENCES
^ NFPA 99: Health Care Facilities Code (2015)
• ^ CSA Z7396.1-17 - Medical gas pipeline systems - Part 1: Pipelines for
medical gases, medical vacuum, medical support gases, and anaesthetic
gas scavenging systems
• ^ ISO 7396-1:2016 Medical gas pipeline systems - Part 1: Pipeline systems
for compressed medical gases and vacuum
• ^ http://www.frca.co.uk/article.aspx?articleid=100342
• External links[edit]
• British Compressed Gases Association website: Department of Health
(United Kingdom) HTM02-01 Medical Gas Pipeline Systems Part A:
Design, installation, validation and verification
• British Compressed Gases Association website: Department of Health
(United Kingdom) HTM02-01 Medical Gas Pipeline Systems Part B:
Operational Management