CARDIOPULMONARY RESUSCITATION

Question 1

Common precipitants of cardiorespiratory arrest?

Answer 1

75% are cardiac:
Arrhythmia e.g. VF, PEA and asystole
Coronary artery abnormalities
MI
Myocardial hypertrophy e.g. HOCM
Valvular heart disease
Inflammatory heart diseases
Dilated cardiomyopathy
Inherited disorders e.g. brugada syndrome
HF
Congenital heart disease

25% respiratory
Airway obstruction e.g. Bronchospasm or severe asthma/COPD
PE
Respiratory muscle weakness e.g. due to spinal cord injury

Question 2

Shockable and non-shockable rhythms

Answer 2

Shockable: pulseless VT, VF
Non-shockable: asystole, PEA

Question 3

What is ROSC/

Answer 3

Return of Spontaneous circulation

Question 4

How can cardiac arrests be prevented?

Answer 4

Healthy diet
Not smoking
Keeping bp healthy
Low alcohol
Healthy weight
Exercise
Optimisation of medical conditions

Question 5

What is the chain of survival?

Answer 5

A series of action that, when properly executed, reduce the mortality associated with cardiac arrest

Question 6

What are the 4 links in the chain of survival?

Answer 6

Early recognition and call for help
Early CPR
Early defibrillation
Early advanced cardiac life support

Question 7

Where should a pt who has had a cardiac arrest be looked after in the hospital?

Answer 7

ICU or coronary care unit

Question 8

Outline ALS first few steps before shock/meds?

Answer 8

Check its safe to approach
Check carotid pulse and look for breathing.if not…
CPR 30:2 attach defibrillator
Call resuscitation team!
Assess rhythm

Question 9

What 3 factors in ALS are said to improve survival rates?

Answer 9

Performing high quality CPR, defibrillation asap and reducing hands off time to <5 seconds per cycle

Question 10

What should you do in thr ALS scenario when you identify a pt with a shockable rhythm e.g. VF or pulseless VT?

Answer 10

Give 1 shock with minimum interruption
Immediately resume CPR for 2 minutes
Then assess rhythm again

Continue this until you have return of spontaneous circulation or you have given 3 shocks

Question 11

Why is it important to have minimal time off the chest before giving a shock?

Answer 11

You want to keep the heart from dilating and this will make it mnore responsive to the shock

Question 12

If the arrest team deliver 3 shocks to the pt and the pt is still in a shockable rhythm what drugs should be administered?

Answer 12

Adrenaline 1mg 1 in 10,000 ever 3-5 minutes
Amiodarone 300mg single dose

Question 13

What drugs do you give in a non-shockable rhythm?

Answer 13

Adrenaline 1mg 1 in 10,000

Question 14

What is adrenaline?

Answer 14

An endogenous catecholamine hormone and neurotransmitter in the sympathetic nervous system
Usually synthesised in the adrenal medulla .

Question 15

Moa of adrenaline?

Answer 15

An alpha and beta adrenoreceptor agonist

In cardiac arrest…
Alpha 1 and 2 - vasoconstriction
Beta 1 - positive chronotropic and inotropic effects

Question 16

Cautions for adrenaline?

Answer 16

IHD
cerebrovascular disease
Diabetes
Hypertension
Hyperthyroidism
Hypokalaemia
Hypertension
Palpitations
Tissue necrosis
Metabolic acidosis

Note: not applicable to emergencies as pt is already dead!

Question 17

Interactions with adrenaline?

Answer 17

Amitrypriline - Increased effects of adrenaline
Beta blockers - causes severe hypertension
MAOI - hypertensive crisis

Question 18

How do you give adrenaline?

Answer 18

1mg IV using 1 in 10,000 solution followed by 20ml flush of 0.9% NaCl

Question 19

Why is there a risk of severe hypertension when beta blockers and adrenaline interact?

Answer 19

Beta blockers prevent adrenaline from acting on beta receptors in the heart but don’t prevent it from acting on alpha receptors in the body so the vasoconstrictive effects of adrenaline on alpha receptors can predominate
This causes severe narrowing of blood vessels without the compensatory vasodilatory effects normally produced by beta receptor activation = hypertension

Question 20

What drug class is amiodarone?

Answer 20

Class 3 anti-arrhythmia

Question 21

MOA of amiodarone?

Answer 21

Inhibits K+ channels involved in repolarisation which prolongs the cardiac action potential and delayed the refractory period

Question 22

Why is amiodarone used instead of lidocaine now in ALS/

Answer 22

As amiodarone does not drop the bp like lidocaine did!

Question 23

What are the challenges of amiodarone?

Answer 23

In complete oral absorption
Large volume of distribution
Extremely long Half-life

This means it needs a large loading dose of up to 3-6 weeks to load!

Question 24

Side effects of amiodarone?

Answer 24

Hypo/hyperthyroidism
Hepatitis
Interstitial lung disease and pulmonary fibrosis
Corneal micro deposits
N&V
Taste disturbance
Light-sensitive blue-grey discolouration
Bradycardia, heart blocks, dysrhythmias, prolonged QT interval
Epididymitis

Question 25

Monitoring for a pt on amiodarone?

Answer 25

TFTs LFTs If IV then ECG

Question 26

Contraindications for admiodarone?

Answer 26

Severe cardiac conduction disturbances (unless they have a pacemaker fitted) Thyroid dysfunction Iodine sensitivity Severe respiratory failure Circulatory collapse

Question 27

Interactions with amiodarone? And what are the effects?

Answer 27

BB, CCB, digoxin - bradycardia Lithium, ondansetron - prolonged QT Steroids, thiazide diuretics, loop diuretics - hypokalaemia Statins - rhabdomyolysis Phenytoin - peripheral neuropathy Warfarin - increased bleeding

Question 28

How do you manage a stable SVT?

Answer 28

Vagal manouvres Adenosine 6mg rapid IV bolus. If no effect give 12mg. If no effect give a further 12 mg. Monitor ECG continuously If sinus rhythm is achieves then probable re-entry paroxysmal SVT. If not achieved then seek expert help and consider possible atrial flutter

Question 29

MOA of adenosine?

Answer 29

Conduction time is decreased by inducing potassium efflux and inhibiting calcium influx through channels in nerve cells, leading to hyperpolarization and and increased threshold for calcium dependent action potentials. Decreased conduction time leads to an antiarrhythmic effect.

Question 30

Contraindications of adenosine?

Answer 30

Asthma/COPD Decompensated HR Long WT/AV block/sick sinus syndrome ?wolf parkinsons white Severe hypotension

Question 31

Interactions with adenosine?

Answer 31

Dipyridamole can increase adenosine exposure Aminophyline/theophylline can decrease adenosine efficacy Some local anaesthetic agents - can cause cardio depression

Question 32

SE of amiodarone?

Answer 32

Headaches Dizziness/syncope Apprehension / sensation of impending doom Sweating and flushing Blurred vision Metallic taste Angina, arrhythmias, AV block Hypotension N&V Bronchospasm, dyspnoea, resp failire

Question 33

Tx for sinus bradycardia if haemodynamically stable?

Answer 33

If no risk of asystole e.g. recent asystole, mobitz II etc then continue obersvation If any risk of asystole then give atropine 500mcg IV and repeat to a maximum of 3mg

Question 34

Tx for sinus bradycardia if haemodynamically unstable?

Answer 34

Atropine 500mcg IV If no satisfactory response repeat to a maximum of 3mg OR transcutaneous pacing OR isoprenaline/adrenaline/alternative

Question 35

MOA of atropine?

Answer 35

Muscarinic antagonist which increases firing of the SAN by blocking the actions of the vagus nerve on the heart

Question 36

Side effects of atropine?

Answer 36

Dry eye/blurry vision Dizziness or drowsiness Dry mouth Flushing Headache N&V Tachycardia Constipation Skin reactions Urinary retention

Question 37

Contraindications of atropine?

Answer 37

Any GI obstruction, urinary retention and myasthenia gravis

Question 38

Interactions with atropine?

Answer 38

Anything with antimuscarinics moa e.g. TCA, muscarinic antagonists, antihistamines, antipsychotics, Phenylephrine - can cause severe hypertension Levodopa - can decrease levodopa’s absorption

Question 39

Tx of anaphylaxis?

Answer 39

Remove allergen if possible IM adrenaline 0.5ml 1 in 1000 - can be repeated every 5 minutes After stabilisation: may give non-sedation oral antihistamine

Question 40

Advice to pt on using an epipen?

Answer 40

Any symptoms -> use epipen “Blue to sky orange to thigh” - use dominant hand, take blue cap off, can go through clothing, go into outside of thigh and count to 10 Remove and rub the thigh for 10 seconds Go to A&E after using epipen Lie on floor with legs in the air if you can tolerate it Advise them not to get up too fast as bp will drop Give epipen to ambulance drivers. Get new one at A&E If Sx dont get better after 5-10 minutes then use second epipen - can be done in either leg

Question 41

Investigations post cardiac arrest?

Answer 41

CXR Frequent 12 lead ECGs Potassium and lactate on VBG/ABG CTPA or echocardiogram USS chest