Gas, Breathing systems and Ventilators Flashcards Preview

FRCA Physics > Gas, Breathing systems and Ventilators > Flashcards

Flashcards in Gas, Breathing systems and Ventilators Deck (206)
Loading flashcards...
1

With regard to the Bain System It requires a test of the bag integrity using the Pethick procedure

False
The Pethick procedure is used to test for Fracture of the inner fresh gas tube at the common gas outlet

2

With regard to the Bain System It is most efficient in controlled ventilation

True

3

With regard to the Bain System It risks failure of safe scavenging if the inner tube fractures at the common gas outlet

False
fracture of the inner fresh gas tube at the common gas outlet results in a massive increase in dead space within the system rather than scavenging failure.

4

With regard to the Bain System It is a coaxial variant of the Mapleson D system

True

5

With regard to the Bain System It can safely be extended to over 5 m in length with no loss in efficiency

True
The length of the system does not affect efficiency and this makes the Bain a useful alternative to the Circle when long systems are required for example in the MRI scanner.

6

The critical temperature of a gas can be correctly defined as ‘The temperature…

Above which it cannot be liquefied by pressure alone

7

With regard to Entonox:
It is a 50:50 mix by weight of oxygen and nitrous oxide

False
Entonox is oxygen and nitrous oxide 50:50 by volume.

8

With regard to Entonox:
It is supplied in cylinders at a pressure of 137 bar

True

9

With regard to Entonox:
It has a pseudo-critical temperature of 5.5 degrees Celsius

False
The two components separate below the pseudo-critical temperature of -5.5 Celsius.

10

With regard to Entonox:
Cylinders should be stored upright

False
horizontal storage increases the surface area for diffusion of oxygen back into the liquid nitrous oxide to reform the entonox mix more quickly but this is not a normal storage requirement per se.

11

With regard to Entonox:
It exists only in gaseous form in a cylinder

True

12

Essential elements of the oxygen VIE include:
A double-skinned steel pressure vessel

True

13

Essential elements of the oxygen VIE include:
A secondary outlet to remove additional vapour from the top of the tank in times of high demand

False
During high demand or cold temperatures, vapour pressure will fall within the VIE and so liquid must be removed from the bottom of the tank and vapourized to meet demand.

14

Essential elements of the oxygen VIE include:
A bourdon gauge to indicate remaining contents of the vessel

False
Because the tank contains predominantly liquid oxygen, contents are primarily measured by weighing scales which form the support base for the tank.

15

Essential elements of the oxygen VIE include:
A system of regulators to reduce supply pressure to 4.1 bar

True

16

Essential elements of the oxygen VIE include:
A safety valve to open at 15 bar

True

17

With regard to standard medical gas cylinders:
Undergo safety checks every three years

False
Cylinders are checked every five years

18

With regard to standard medical gas cylinders:
Have plastic neck rings to signify year of manufacture

False
Safety check dates rather than those of manufacture, are indicated by coloured plastic rings around the cylinder neck.

19

With regard to standard medical gas cylinders:
Are made of molybdenum steel

True

20

With regard to standard medical gas cylinders:
Can withstand pressures 65-70% above working pressure

True

21

With regard to standard medical gas cylinders:
Are safe in MRI scanners

False
Standard cylinders are ferromagnetic (molybdenum steel) and are extremely dangerous in MRI scanners – specialist composite or aluminium cylinders are required in this environment.

22

With regard to the Mapleson A System:
It is most efficient when used for controlled ventilation

False
The Mapleson A system is most efficient in spontaneous ventilation

23

With regard to the Mapleson A System:
It is available in parallel and coaxial configurations

True

24

With regard to the Mapleson A System:
It removes the weight of the APL valve from the patient’s face when used in the Magill configuration

False
The Lack modification of the original Magill removes the APL valve from the patient mask to the anaesthestic machine end of the system.

25

With regard to the Mapleson A System:
It requires a fresh gas flow 1.5-2 x minute volume when used for spontaneous ventilation

False
spontaneous ventilation requiring a fresh gas flow of approximately 70% minute ventilation.

26

With regard to the Mapleson A System:
It has an inner expiratory and outer inspiratory tube in the coaxial variants

True

27

With regard to soda lime:
It is primarily composed of calcium salts

True

28

With regard to soda lime:
It is the active component of a Cardiff Aldasorber

False
The Cardiff Aldasorber adsorbs anaesthetic volatile agents onto activated charcoal.

29

With regard to soda lime:
1kg will absorb 120 L of carbon dioxide

True

30

With regard to soda lime:
It will become white when exhausted

False
Commonly, dyes change granules from white to violet or pink to white when exhausted.