IHS

Question 1

Facts about N2O

Answer 1

Colourless gas
Sweet odour
Stored as a liquid
1.5x heavier than air
Non flammable
Non irritant
Insoluble in blood

Question 2

What are clinical effectS of N2O

Answer 2

Rapid onset and recovery
Depression of CNS
Relaxation
Parasthesia
Sedation
Analgesia
Euphoria

Question 3

What is a beneficial side effect of IHS for IVS

Answer 3

Vasodilation

Question 4

What is the max therapeutic doses of N2O

Answer 4

Never above 70% rarely above 50%

Question 5

What are chronic side effects of N2O exposure

Answer 5

Oxidation of vitamin B12 causing a reduction in methionine synthetase which increases risk of cancer neurological hepatic renal and haematological issues.

Question 6

How does N2O work

Answer 6

Increased concentration in lungs forces into blood where it then acts on brain

Question 7

What are the indications for IHS

Answer 7

Same as IVS but this has less risk and is less invasive

Question 8

Contraindications of IHS

Answer 8

URTI, blocked nose, chronic respiratory disease, methotrexate and bleomycin

Question 9

What are benefits of IHS

Answer 9

Non invasive, titrateable, minimal effects on CV &RS systems, easily reversed and minimal interactions

Question 10

What are disadvantages of IHS

Answer 10

Nasal hood is not nice, compliance required to an extent, continuous N2O required

Question 11

What are the IHS guidelines

Answer 11

IACSD SDCEP NICE