3- managing cardiac arrest

Question 1

how do we recognise cardiac arrest?

Answer 1

• unresponsive
• abnormal breathing
• absent pulse

Question 2

what is cardiac arrest

Answer 2

= sudden termination of cardiac function so no circulating oxygen to vital organs →ischaemia and cell death

Question 3

what is good quality CPR?

Answer 3

• start chest as soon as possible
• deliver compressions on lower half of the sternum (centre of chest)
• compress to depth of at least 5 cm but no more than 6cm
• compress the chest at rate of 100-120 bpm
• allow chest to recoil completely after each compression
• perform chest compressions on firm surface

Question 4

what should you do if cardiac arrest?

Answer 4

1. To prevent cardiac arrest happening in the first place & early recognition of arrest
2. Call for help – 999/2222
3. Early & good quality CPR – to buy time
4. Early defibrillation
5. Get hold of an AED
6. Best chance of survival is defibrillation in a VF/VT arrest.
7. Post resuscitation care
8. to restore quality of life
9. A to E assessment

Question 5

how do we deliver oxygen to tissue? how do you calculate?

Answer 5

arterial oxygen content (CaO2) x cardiac output (CO)

CaO2 = (1.34 x haemoglobin saturated with oxygen x peripheral oxygen saturation (SpO2)) x (0.003 x partial pressure of oxygen (PaO2))

CO = stroke volume x HR

Question 6

what is VO2 and DO2 and what balance leads to aerobic/anaerobic respiration?

Answer 6

VO2 = oxygen consumption by tissues
D02 = oxygen delivery to tissues

If DO2> VO2 →aerobic respiration

If VO2 > DO2 -> anaerobic respiration, tissue hypoxia, ischaemia…. death

Question 7

in advanced life response what is criteria and what is priotity?

Answer 7

• unresponsive & cardiac arrest
• good quality CPR & early defib is still important - 5sec max interruptions

Question 8

in advanced life response - what do you do if
a) shockable
b) non-shockable

Answer 8

a) if shockable (ventricular fibrillation, pulseless ventricular tachycardia)
- after 3 shocks→amiodarone given
- also adrenaline given every 3-5 mins after that

b) if non-shockable:
- just go straight into chest compressions
- you give adrenaline straight away and give repeat dose every 3-5 mins

Question 9

is ventricular fibrillation shockable?

Answer 9

yes - it’s not compatible with life & always pulseless

Question 10

is monomorphic ventricular tachycardia shockable? how does it look on ECG?

Answer 10

yes - can be pulseless or “conscious”

on ECG - regular, broad complex tachycardia, monomorphic hence uniform QRS complexes within each lead

Question 11

is polymorphic ventricular tachycardia shockable?

Answer 11

Polymorphic VT or torsades de pointes (twisting of the peaks)

• QRS complexes not uniform
• can be pulseless or pulse - if pulseless can deliver shock

Question 12

what are the 4H’s and 4T’s - causes of cardiorespiratory arrest?

Answer 12

4H’s:
- hypoxia
- hypovolaemia
- hypothermia
- hyperkalaemia, hypokalaemia

4T’s:
- Tension pneumothorax
- Tamponade
- Toxins
- Thrombus

Question 13

is asystole shockable?

Answer 13

no - non shockable - it’s just flat line on ECG

Question 14

is sinus rhythm shockable?

Answer 14

If no pulse -> pulseless electrical activity (PEA)

Non-shockable

pulseless electrical activity - although conduction normal, no contraction is occurring (or not effectively)

Question 15

what are signs of returns of spontaneous circulation (ROSC)?

Answer 15

• signs of life (respiratory effort, pulse)
• rise in ETCO2 (product of respiration)

Question 16

what is the ongoing care you would provide for post cardiac arrest (once ROSC)?

Answer 16

• ABCDE approach
• urgent cardiac catheterisation +/- PCI if cardiac origin of arrest
• ICU: targeted temperature management (TTM) for those unresponsive after ROSC; neuro-protective ventilation; CV support; seizure management
• Neurological prognostication >72h
• Ongoing treatment, rehabilitation and secondary prevention for patients that survive

Question 17

when do you terminate CPR?

Answer 17

• Valid and relevant advance directive / DNAR
• Obvious mortal injury / irreversible death
• Safety threat to ALS provider
• Persistent asystole >20 min despite ALS without reversible cause identified

Question 18

what are most important things to prevent cardiac arrest?

Answer 18

Early recognition AND intervention

Question 19

what is ABCDE assessment?

Answer 19

A = airways
B = breathing
C = circulation
D = disability
E = exposure

Question 20

what is A in ABCDE?

Answer 20

A = airway

• head tilt, chin lift (then jaw thrust & suction if needed)
• assess by talking, distressed breathing, see saw breathing, shortness of breath

Question 21

what is B in ABCDE?

Answer 21

B = breathing

• early SpO2 monitoring, supplement O2, ventilation support, drugs, acute interventions (needle decompression)
• assess: look respiratory rate & effort, sweating or fatigue. listen: wheezing or crackle sounds. feel: trachea, expansion, percussion, surgical emphysema

Question 22

what is C in ABCDE?

Answer 22

C = circulation

• CCM 3-lead, Large bore (14G/16G) intravenous cannulae, Bloods (FBC,UE, VBG, Lactate, G+S, coag), Fluid challenge, ECG, Reassess
• assess colour temp & capillary refill, heart rate, peripheral pulse, heart sounds, clinical signs of hemorrhage etc

Question 23

what is D in ABCDE?

Answer 23

D = disability

• maintain normoglycaemia, reversal agents (BZD, opoids), seizure control, patient positioning
• assess by profound hypoxia, hypercapnia, hypoglycaemia, AVCPU, pupils, blood glucose, temp

Question 24

what is E in ABCDE?

Answer 24

E = exposure

• differentials & ensure normothermia
• remove clothes to enable examinations for bleeding, injury, rashes - avoid heat loss & maintain dignity