Ch 41 Storage And Delivery Of Medical Gases Flashcards
What are the three types of classifications for medical gases?
Laboratory
Therapeutic
Anesthetic
What are laboratory gases used for?
Used for equipment calibration and diagnostic testing
What are therapeutic gases used for?
Used to relieve symptoms and improve oxygenation of patients with hypoxemia
Which gases are combined with O2 to provide anesthesia during surgery?
Anesthetic Gases
What are the two classifications of medical compressed gases in terms of fire hazards
Nonflammable and Flammable
What do the molecular sieves absorb
Nitrogen, trace gases, and water vapor from air
What is left behind after sieves do their job
Concentrated mixture of more than 90% Oxygen for patient use
What is the most common and least expensive method for producing O2?
Fractional Distillation
What’s the second method of producing O2?
Semipermeable Plastic Membrane
This system can produce an O2
mixture of approximately 40%.
Semipermeable Plastic Membrane method uses a vacuum to pull ambient air
through a semipermeable plastic membrane
that allows O2 and water vapor to pass through
faster than N2
What are the characteristics of Oxygen?
Colorless, odorless, transparent, and tasteless
At STPD: Has a density of 1.429 g/L
• Slightly heavier than air (1.29 g/L)
• Not very soluble in water
• At room temperature and 1 atm pressure, only
3.3 ml of O2 dissolves in 100 ml of water
Characteristics of medical air
Colorless, odorless, naturally occurring
20.95% O2, 78.1%
nitrogen, about 1% trace gases,
STPD, density is 1.29 g/L
Characteristics of CO2
CO2 is a colorless, odorless gas and taste slightly acidic,
approximately 1.5 times heavier than air, does not
support life and is nonflammable.
• Common uses for CO2 mixtures
• Calibration of blood gas analyzers
• Diagnostic purposes in clinical laboratory
Characteristics of Helium (He)
Odorless, tasteless, nonflammable, and chemically
and physiologically inert
• Density of 0.1785 g/L; much less than air
• Does not support life therefore it must be mixed with
at least 20% O2
Characteristics of Heliox (He/O2)
Therapeutic use
• Manages severe cases of airway obstruction, reduces WOB
• Lower density makes gas flow more laminar
• If a Heliox regulator is not available, the use of an oxygen flowmeter is acceptable
however, the RT must calculate the new flow.
• 80/20% concentration use 1.8 factor
• 70/30% concentration use 1.6 factor
• Example: 80/20 mixture with a flow set at 10 lpm on an oxygen flowmeter.
• 10 lpm x 1.8 = 18 lpm
• Example: 70/30 mixture with a flow of 10 lpm on an oxygen flowmeter.
• 10 lpm x 1.6 = 16 lpm
Characteristics of Nitric Oxide (NO)
• Colorless, nonflammable, toxic gas that supports combustion
• Pulmonary vasodilator agent
• Strong respiratory irritant that can cause pneumonitis and pulmonary edema, must be mixed with O2
Exposure to high concentrations alone can cause methemoglobinemia, which can cause tissue hypoxia
• FDA approved for use in treatment of term and near-term infants with hypoxic respiratory failure.
• Dose: 20 part per million (ppm)
Laughing Gas
Nitrous Oxide (N2O)
How are gas cylinders marked and identified?
Color Coded and marked with metal stamping on shoulder
What does the metal stamping on the shoulder of gas cylinders indicate?
indicates size, normal filling pressure, serial number, ownership, and method of manufacturer
What is the sign for a DOT 10 year approval testing
An asterisk next to test date of metal stamping
How often are safety tests conducted by DOT on gas cylinders
Every 5 or 10 years
What are the sizes of the gas cylinders
Sizes E through AA referred to as “small cylinders”,
used most often for transporting patients and for
anesthetic gases, have unique valves and connecting
mechanisms known as a post valve and yoke
connector.
• Large cylinders (F through H and K) have a threaded
valve outlet
Large cylinders such as H/K, G and M, have the threaded valve outlet. true or false ?
True
Post valve used for yoke connector is on the smaller cylinders, such as E through AA
True
