Managing Cardiac Arrest

Question 1

d: cardiac arrest

Answer 1

effective cessation of the heart, so no circulation and therefore no oxygen delivered

Question 2

How is CA recognised?

Answer 2

unresponsive patient
not breathing normally
no pulse

Question 3

O2 delivery equation?

Answer 3

DO2 = SaO2 x [Hb] x O2cc1 x CO (HR x SV2)

Question 4

What is the presenting rhythm in most cases? and whgat does this mean?

Answer 4

VF/VT

shockable able to be defibrillated

Question 5

In hospital what is CA more commonly shockable/non-shockable?

Answer 5

not shockable

Question 6

Name 2 preceding symptoms that are common of CA

Answer 6

hypoxia

hypotension

Question 7

Name the common causes of cardiac arrest

Answer 7

problems involving: breathing
airway
circulation

Question 8

How can we improve O2 sats?

Answer 8

– ↑FiO2, Clear airway, Adequate breathing

Question 9

How can improve O2 delivery factors in relation [Hb]?

Answer 9

• Transfusion trigger, Treat anaemia - Gp&S / X-match, IV access, (Fe etc)

Question 10

How can improve O2 delivery factors in relation BP/HR?

Answer 10

– Atropine or β-stimulant (e.g. ephedrine) for bradycardia, pace

Question 11

hOW CAN WE INCREASE Cardiac preload?

Answer 11

– IV fluids, raise legs

Question 12

How can we improve contractility CPR?

Answer 12

treat cause (e.g. PCI for MI)

Question 13

How can we treat XS afterload? and eg

Answer 13

e.g. HBP) use vasodilators

Question 14

How can we reduce afterload? and eg

Answer 14

e.g. septic shock) use vasoconstrictors

Question 15

What approach do you use for CPR?

Answer 15

ABCDE

Question 16

How is SaO2 assessed clinically?

Answer 16

), pulse oximetry, arterial blood gas (gold standard)

Question 17

How is haemoglobin concentration monitored clinically?

Answer 17

clinical (not reliable), part of FBC (full blood count), bedside (e.g. Hemocue)

Question 18

How is HR measured clinically?

Answer 18

pulse, pulse oximetry, ECG monitor with sound on or arterial BP monitor

Question 19

How do we assess BP?

Answer 19

BP = CO x TPR (total peripheral resistance main physiological “afterload”)
Once Heart Rate accounted for then BP determined by SV and/or TPR
SV depends on preload, contractility, afterload
BP change ALWAYS due to HR, preload, contractility or afterload change
Use clinical info to determine which

Question 20

Name some causes of cardiorespiratory arrest?

Answer 20

CNS depression - tongue

Lumen blocked - blood, vomit, foreign body

Swelling - trauma, infection, inflammation

Muscle - laryngospasm, bronchospasm

Question 21

how is airway obstruction recognised?

Answer 21

Talking
Difficulty breathing, distressed, choking
Shortness of breath
Noisy breathing
stridor, wheeze, gurgling
See-saw respiratory pattern, accessory muscles

Question 22

How is airway opbstruction treated?

Answer 22

Airway opening
		- i.e. head tilt, chin lift, jaw thrust, suction
Simple adjuncts
Advanced techniques
		- e.g. LMA, tracheal tube
Oxygen! (increase FiO2)

Question 23

Name the causes of breathing problems?

Answer 23

Airway problems!

Decreased respiratory drive
CNS depression
Decreased respiratory effort
muscle weakness, nerve damage, restrictive chest defect, pain from fractured ribs
Lung disorders
pneumothorax, haemothorax, infection, acute exacerbation COPD, asthma, pulmonary embolus, ARDS

Question 24

How are breathing problems recognised?

Answer 24

Look
respiratory distress, accessory muscles, cyanosis, respiratory rate, chest deformity, conscious level
Listen
noisy breathing, breath sounds
Feel
expansion, percussion, tracheal position

Question 25

How are breathing problems ttreated?

Answer 25

``` Airway Oxygen Treat underlying cause to improve breathing - e.g. drain pneumothorax Support breathing if inadequate - e.g. ventilate with bag mask ```

Question 26

Name the primary causes or circulatory problems?

Answer 26

``` Acute coronary syndromes Dysrhythmias Hypertensive heart disease Valve disease Drugs Hereditary cardiac diseases Electrolyte / acid base abnormalities Electrocution ```

Question 27

Name the secondary causes of circulatory problems?

Answer 27

``` Asphyxia Hypoxaemia Blood loss Hypothermia Septic shock ```

Question 28

Describe the ABCDE approach to ill circulation?

Answer 28

Recognition of circulation problems ([Hb], CO = HR x SV) ``` General exam – distress, pallor etc Indicators of organ perfusion chest pain, mental state, urine output Blood pressure Pulse – tachycardia, bradycardia Peripheral perfusion - capillary refill time (CRT) Bleeding, fluid losses, JVP, CVP ```

Question 29

How are circulatory problems treated ABCDE?

Answer 29

``` 1st ensure Airway, Breathing, O2 IV / IO access, take bloods Treat cause Fluid challenge Inotropes/vasopressors Oxygen/Aspirin/Nitrates/ Morphine for ACS Haemodynamic monitoring ```

Question 30

Describe the ABCDE approach to critically ill for disability?

Answer 30

Recognition – AVPU or GCS + pupils Treatment - ABC ``` Treat underlying cause Blood glucose if < 3 mmol l-1 give glucose Consider lateral (recovery) position Check drug chart ```

Question 31

Describe the ABCDE approach to ill exposure?

Answer 31

``` Remove clothes to enable thorough examination (to avoid missing causes of problems) - e.g. injuries, bleeding, rashes BUT! Avoid heat loss Maintain dignity ```

Question 32

If there's no response what do you do?

Answer 32

shout help

Question 33

describe ECG for VF?

Answer 33

``` Bizarre irregular waveform No recognisable QRS complexes Random frequency and amplitude Unco-ordinated electrical activity Coarse / fine Exclude artifact movement electrical interference ```

Question 34

Describe the VT ECG? both the monomorphic and polymorphic type

Answer 34

``` Monomorphic VT Broad complex rhythm Rapid rate Constant QRS morphology Polymorphic VT Torsade de pointes ```

Question 35

When is a precordial thump only used?

Answer 35

Only used if defibrillator not immediately available in witnessed and monitored VF/VT cardiac arrest

Question 36

When is VT shockable?

Answer 36

if it pulses

Question 37

describe how manual defibrillator is used?

Answer 37

``` Diagnose VF/VT from ECG and signs of cardiac arrest Select correct energy level Charge paddles on patient Shout “stand clear/O2 away” Visual check of area Check monitor “Stand clear” to CPR provider Deliver shock Resume CPR immediately Minimise pause 5 secs by planning/communicating actions ```