Medical Gases

Question 1

Contraindications for the use of oxygen

Answer 1

For patients with Chronic Obstructive Pulmonary Disease, oxygen in high concentrations is potentially deleterious, however it is unlikely high levels of oxygen within the first hour of trauma or serious illness will cause significant side effects.

Question 2

What is Entonox gas ?

Answer 2

Inhaled analgesic to assist in the safe management of fractures or dislocations.

Question 3

Contra-indications to the use of Entonox

Answer 3

Head Injuries and ↓GCS: Increasing the possibility of drowsiness or loss of consciousness and possibly expanding an aerocele.

Chest Injuries: Entonox is 34 times more soluble than nitrogen. Consequently it diffuses in to cavities more rapidly than nitrogen diffuses out . This will cause an increase in the volume of a space and an increase in the pressure effect of a gas filled cavity. This increases the risk of a pneumothorax or the conversion of a simple pneumothorax to a tension pneumothorax.

Air Embolism: increased expansion

Maxillofacial Injuries: increased risk of surgical emphysema and blow out fracture

Decompression Sickness: due to increased solubility of nitrogen bubbles in the bloodstream

Intoxication: May increase the effects of alcohol or drugs

Question 4

What is Penthrox?

Answer 4

Analgesic gas

Question 5

Penthrox is contraindicated when?

Answer 5

Head injuries & ↓ GCS: Increasing the possibility of drowsiness or loss of consciousness

Patient with hepato renal disease

Under 18’s

Athletes with reactions to general anaesthetics

Severely shocked athletes

6 mls previously used within the 24 hour period