LIVES Level 4 Entonox PMA

Question 1

Entonox

Inclusion Criteria

Answer 1

Adult patients (12+ yrs, capable of following the administration instructions and activating the demand valve) presenting with:
- Moderate to severe pain from isolated limb injuries where movement of the patient is required (including removal from the scene) in the absence of any exclusion criteria

Question 2

Entonox

Exclusion Criteria

Answer 2

• Severe head injuries with impaired conscious level (entonox will further impair consciousness)
• Chest injuries and other conditions where pneumothorax is suspected, entonox may expand this
• Decompression sickeness (the bends) where entonox will expand nitrogen bubbles within the blood stream. Patients that have gone diving within the past 24hrs can be considered to be at risk.
• Patients that have had eye surgery within the past 4 weeks, a gas bubble may form within the eye globe
• Violently disturbed psychiatric patients

Question 3

Entonox

Cautions

Answer 3

• Any patient at risk of having air within body cavities as a result of penetrating injuries/ polytrauma/ abdominal obstruction
  e. g. pneumoperitoneum, pneumomediastinum
• Patients requiring > 50% O2 (i.e. critical patients per BTS oxygen guidelines)
• Alcohol and drug intoxication
• Young children
• Any individual unable to understand the concept of self-administration

Question 4

Entonox

Name, Form, Strength

Answer 4

Entonox is a combination of 50% Nitrous Oxide and 50% Oxygen.
It is stored in medical cylinders that have a blue body with white shoulders.

Question 5

Entonox

Legal Status

Answer 5

Prescription Only Medicine

Question 6

Entonox

Route of Administration

Answer 6

Patient self-administered inhalation via face mask or mouthpiece following suitable instruction.

Pt must be capable of holding the mouthpiece or mask to avoid inadvertent overdose.
Pt must be capable of generating sufficient negative pressure on inhalation to activate the valve.

Ensure gaseous admixture in cold temperatures

Question 7

Entonox

Cold Temperatures

Answer 7

In cold temperatures, the gases in the cylinder will separate. Administering this can lead to severe hypoxia, as no oxygen will be present.

Invert cylinder at least 3 times to ensure gaseous admixture.
Continue to invert cylinder during administration.

Question 8

Entonox
Dose:
Adults & Children (> 12 yrs)

Answer 8

Self-administered inhalation via face-mask or mouthpiece

Patient should be advised to stop inhaling gas once adequate analgesia has been achieved

Question 9

Entonox

Time to Take Effect & Time to Maximum Effect

Answer 9

With correct self-administration:
Time to take effect = 3-5 minutes
Time to maximum effect = 5-10 minutes

Question 10

Entonox

Maximum Dosing

Answer 10

For acute administration for analgesic purposes

Pt self-adminstered

Question 11

Entonox

Explanation of how to self-administer

Answer 11

Use button to open valve (before attaching mouthpiece to blow out dust)
When this is done, explain to the patient that this is the noise that should be made by them inhaling.
Pt should not press the button!

3-5 minutes to take effect!

Question 12

Entonox

Quantifying Effect

Answer 12

Take a patient pain score before administration.
Take a patient pain score after 3-5 minutes.
Take a patient pain score after 10 minutes.

Question 13

Entonox

Adverse Effects

Answer 13

Include:
Drowsiness
Confusion

Rapidly reversed on discontinuation