Managing Cardiac Arrest Flashcards
d: cardiac arrest
effective cessation of the heart, so no circulation and therefore no oxygen delivered
How is CA recognised?
unresponsive patient
not breathing normally
no pulse
O2 delivery equation?
DO2 = SaO2 x [Hb] x O2cc1 x CO (HR x SV2)
What is the presenting rhythm in most cases? and whgat does this mean?
VF/VT
shockable able to be defibrillated
In hospital what is CA more commonly shockable/non-shockable?
not shockable
Name 2 preceding symptoms that are common of CA
hypoxia
hypotension
Name the common causes of cardiac arrest
problems involving: breathing
airway
circulation
How can we improve O2 sats?
– ↑FiO2, Clear airway, Adequate breathing
How can improve O2 delivery factors in relation [Hb]?
- Transfusion trigger, Treat anaemia - Gp&S / X-match, IV access, (Fe etc)
How can improve O2 delivery factors in relation BP/HR?
– Atropine or β-stimulant (e.g. ephedrine) for bradycardia, pace
hOW CAN WE INCREASE Cardiac preload?
– IV fluids, raise legs
How can we improve contractility CPR?
treat cause (e.g. PCI for MI)
How can we treat XS afterload? and eg
e.g. HBP) use vasodilators
How can we reduce afterload? and eg
e.g. septic shock) use vasoconstrictors
What approach do you use for CPR?
ABCDE
How is SaO2 assessed clinically?
), pulse oximetry, arterial blood gas (gold standard)
How is haemoglobin concentration monitored clinically?
clinical (not reliable), part of FBC (full blood count), bedside (e.g. Hemocue)
How is HR measured clinically?
pulse, pulse oximetry, ECG monitor with sound on or arterial BP monitor
How do we assess BP?
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
Name some causes of cardiorespiratory arrest?
CNS depression - tongue
Lumen blocked - blood, vomit, foreign body
Swelling - trauma, infection, inflammation
Muscle - laryngospasm, bronchospasm
how is airway obstruction recognised?
Talking
Difficulty breathing, distressed, choking
Shortness of breath
Noisy breathing
stridor, wheeze, gurgling
See-saw respiratory pattern, accessory muscles
How is airway opbstruction treated?
Airway opening - i.e. head tilt, chin lift, jaw thrust, suction Simple adjuncts Advanced techniques - e.g. LMA, tracheal tube Oxygen! (increase FiO2)
Name the causes of breathing problems?
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
How are breathing problems recognised?
Look respiratory distress, accessory muscles, cyanosis, respiratory rate, chest deformity, conscious level Listen noisy breathing, breath sounds Feel expansion, percussion, tracheal position
How are breathing problems ttreated?
Airway Oxygen Treat underlying cause to improve breathing - e.g. drain pneumothorax Support breathing if inadequate - e.g. ventilate with bag mask
Name the primary causes or circulatory problems?
Acute coronary syndromes Dysrhythmias Hypertensive heart disease Valve disease Drugs Hereditary cardiac diseases Electrolyte / acid base abnormalities Electrocution
Name the secondary causes of circulatory problems?
Asphyxia Hypoxaemia Blood loss Hypothermia Septic shock
Describe the ABCDE approach to ill circulation?
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
How are circulatory problems treated ABCDE?
1st ensure Airway, Breathing, O2 IV / IO access, take bloods Treat cause Fluid challenge Inotropes/vasopressors Oxygen/Aspirin/Nitrates/ Morphine for ACS Haemodynamic monitoring
Describe the ABCDE approach to critically ill for disability?
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
Describe the ABCDE approach to ill exposure?
Remove clothes to enable thorough examination (to avoid missing causes of problems) - e.g. injuries, bleeding, rashes BUT! Avoid heat loss Maintain dignity
If there’s no response what do you do?
shout help
describe ECG for VF?
Bizarre irregular waveform No recognisable QRS complexes Random frequency and amplitude Unco-ordinated electrical activity Coarse / fine Exclude artifact movement electrical interference
Describe the VT ECG? both the monomorphic and polymorphic type
Monomorphic VT Broad complex rhythm Rapid rate Constant QRS morphology Polymorphic VT Torsade de pointes
When is a precordial thump only used?
Only used if defibrillator not immediately available in witnessed and monitored VF/VT cardiac arrest
When is VT shockable?
if it pulses
describe how manual defibrillator is used?
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
