Adrenaline

Question 1

Adrenaline Mechanism of Action

Answer 1

• Adrenaline stimulates alpha and beta receptors, with the predominant effects occurring at alpha 1, beta 1 and beta 2 receptors.
• Alpha 1 stimulation causes smooth muscle contraction, vasoconstriction of
blood vessels and stimulation of glycogenolysis and gluconeogenesis.
• Beta 1 stimulation causes an increase in inotropy (cardiac contractility), an increase in chronotropy (heart rate) and an increase in dromotropy (speed of electrical conduction within the heart).
• Beta 2 stimulation causes smooth muscle relaxation, skeletal muscle vasodilation, bronchodilation, and stabilisation of mast cell membranes,
reducing histamine release.

Question 2

Adrenaline Scope of Practice

Answer 2

• EMTs: nebulised, IM, IN and topical adrenaline.
• Paramedics: all of the above and adrenaline IV for cardiac arrest.
• ICPs: all indications and all routes.

Question 3

Adrenaline Indications

Answer 3

Cardiac arrest.
Anaphylaxis.
Severe asthma.
Imminent respiratory arrest from COPD.
Severe bradycardia.
Blood pressure support if unresponsive to metaraminol.
Septic shock, cardiogenic shock and neurogenic shock unresponsive to 0.9% sodium chloride IV and metaraminol IV.
Moderate to severe stridor.
IN for clinically significant epistaxis.
Topical for clinically significant bleeding from a wound.

Question 4

Adrenaline Contraindications

Answer 4

None

Question 5

Adrenaline Cautions

Answer 5

Myocardial ischaemia. Adrenaline will increase myocardial oxygen consumption.
Tachydysrhythmias. Adrenaline will usually make tachydysrhythmias worse.

Question 6

Adrenaline Use in pregnancy or breastfeeding

Answer 6

• Safe and should be administered when indicated.

Question 7

Adrenaline Topical Administration

Answer 7

Topical: dilute each mg of adrenaline to a total of 10 ml using 0.9% sodium chloride. This solution is 1:10,000 and contains 0.1 mg/ml. Apply topically in addition to direct pressure.

Question 8

Adrenaline IN Administration

Answer 8

dilute each mg of adrenaline to a total of 10 ml using 0.9% sodium chloride.
This solution is 1:10,000 and contains 0.1 mg/ml. Administer the appropriate dose into each bleeding nostril using a mucosal atomising device, in addition
to direct pressure.

Question 9

Adrenaline Nebuliser administration

Answer 9

Undiluted

Question 10

Adrenaline IM administration

Answer 10

Administer undiluted. The preferred IM site is the lateral thigh. If this site is
not suitable use the lateral upper arm.

Question 11

Adrenaline Cardiac Arrest administration

Answer 11

Adults and children whose weight has been rounded to 50 kg or more:
administer undiluted as an IV bolus.
b) Children whose weight has been rounded to 40 kg or less: dilute 1 mg of adrenaline to a total of 10 ml using 0.9% sodium chloride. This solution is 1:10,000 and contains 0.1 mg/ml. Draw up the dose from this solution and administer as an IV bolus.

Question 12

Adrenaline IV administration (Infusion)

Answer 12

1mg adrenaline in 1 L Sodium chloride
1 : 1,000,000
0.001mg/ml

Question 13

Adrenaline Adverse effects

Answer 13

• Tachycardia.
• Tachydysrhythmia.
• Myocardial ischaemia.
• Ventricular ectopy.
• Hypertension.
• Nausea and vomiting.
• Tremor, anxiety and sweating.
• Hyperglycaemia.

Question 14

Adrenaline Usual onset of effect

Answer 14

• IV: 5-10 seconds.
• IM: 2-5 minutes.
• Nebulised, IN and topical: on contact with the target site.

Question 15

Adrenaline Usual duration of effect

Answer 15

• The cardiovascular effects last 5-15 minutes.

* The mast cell membrane effects may last for several hours.

Question 16

Adrenaline Pharmacokinetics

Answer 16

• Adrenaline is metabolised by the liver and taken up by sympathetic nerve endings.
• There are no significant effects from liver impairment on acute administration.

Question 17

Adrenaline Common interactions

Answer 17

• Increased doses may be required if the patient is taking a beta-blocker or a calcium channel blocker. This effect is particularly prominent in the setting of
poisoning if a large dose of a beta-blocker and/or calcium channel blocker has
been taken.

Question 18

Adrenaline a1 Receptor Locations

Answer 18

Located in smooth muscle membrane

Promotes contraction of smoot muscle of peripheral blood vessels

Question 19

Adrenaline b1 Receptor Locations

Answer 19

Located in cardiac muscle cell membrane

Stimulates HR and myocardial contractility

Question 20

Adrenaline b2 Receptor Locations

Answer 20

Located in brochioles of the heart, and arteries of skeletal muscles
Stimulate increased diameter of bronchioles
Stimulates dilation of vessels in skeletal muscles