Chapter 41: Storage and Delivery of Medical Gases (Exam 2)

Exam 2

What are 3 categories Medical Gases are classified as?

laboratory, therapeutic, or anesthetic

What is relationship of flammability and combustion of O2 gas?

nonflammable but greatly accelerates combustion

What are two physical separation methods of O2 concentrator?

Molecular sieves and Oxygen concentrators (vacuum)

Does CO2 support combustion?

no

How does density of Helium relate to Oxygen and what are the two mixtures?

He is less dense than O2; 20:80 and 30:70

What are the two factors for total flow for Heliox?

80/20 is 1.8 and 70/30 is 1.6

What is Heliox mainly used for and how does it help airways?

for severe cases of airway obstruction and produces laminar flow

What can high concentrations of Nitric Oxide cause?

methemoglobinemia which can cause tissue hypoxia

What set of patients is Nitric Oxide FDA approved for?

term and near-term infants with hypoxic respiratory failure

How often are safety tests conducted on gas cyclinders?

5 or 10 years

What does the Cylinder safety relief valve do?

designed to vent gas to atmosphere if tank is heated preventing tank pressure from becoming too high

What are the 3 basic designs for cylinder safety relief valves?

Frangible metal disk, Fusible plug melts, Spring-loaded valve opens

How much more can cylinders be filled above service pressure for compressed gas?

10%

What are 3 liquid gasses we deal with?

CO2, N2O, and O2

How is filling density calculated for liquified gasses?

the ratio between weight of liquid gas put into cylinder and weight water cylinder would contain if full

How does volume of gas in cylinder relate to pressure?

directly proportional

How to know how much liquid gas in cylinder?

only weight of cylinder indicates amount of gas inside, pressure does not relate

What 3 factors affect duration of flow for gas cylinder?

gas flow, cylinder size, and cylinder pressure at start of therapy

What are the 3 types of Bulk oxygen gas supply systems?

Alternating supply system or cylinder manifold system, Cylinder supply system with reserve supply, Bulk gas system with reserve

What is the Central piping system and what is pressure associated with it?

used to deliver compressed gas to all areas throughout hospital reduced to a standard working pressure of 50 psi

What are zone valves?

valve that shuts off gas use in system maintenance or in case of fire

What 3 systems are used to ensure correct gas source?

American Standard Safety System (ASSS), Pin-Index Safety System (PISS), Diameter-Index Safety System (DISS)

What is the DISS system used for?

low-pressure gas connectors such as flowmeter or pressure-reducing valves

What does a reducing valve do?

reduce gas pressure to useable level

What is Flowmeter and Regulator used to control?

Flowmeter to control flow to patient while regulator control both pressure and flow

What are the 3 categories of flowmeters?

Flow restrictor, Bourdon gauge, and Thorpe tube

What flowmeter is ideal for patient transport and why?

Bourdon gauge; not gravity dependent

What is the Integrated oxygen cylinder we might use?

Grab’n Go System

For Bourdon Gauge and Thorpe Tube, which is fixed or variable orifice?

Bourdon = Fixed orifice and Thorpe = Variable orifice

What is difference between compensated and uncompensated Thorpe Tube systems?

compensated prevents changes in downstream resistance or back pressure negating inaccuracy of meter while uncompensated is affected by these factors and leads to inaccuracy