3- managing cardiac arrest Flashcards
how do we recognise cardiac arrest?
- unresponsive
- abnormal breathing
- absent pulse
what is cardiac arrest
= sudden termination of cardiac function so no circulating oxygen to vital organs →ischaemia and cell death
what is good quality CPR?
- 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
what should you do if cardiac arrest?
- To prevent cardiac arrest happening in the first place & early recognition of arrest
- Call for help – 999/2222
- Early & good quality CPR – to buy time
- Early defibrillation
- Get hold of an AED
- Best chance of survival is defibrillation in a VF/VT arrest.
- Post resuscitation care
- to restore quality of life
- A to E assessment
how do we deliver oxygen to tissue? how do you calculate?
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
what is VO2 and DO2 and what balance leads to aerobic/anaerobic respiration?
VO2 = oxygen consumption by tissues
D02 = oxygen delivery to tissues
If DO2> VO2 →aerobic respiration
If VO2 > DO2 -> anaerobic respiration, tissue hypoxia, ischaemia…. death
in advanced life response what is criteria and what is priotity?
- unresponsive & cardiac arrest
- good quality CPR & early defib is still important - 5sec max interruptions
in advanced life response - what do you do if
a) shockable
b) non-shockable
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
is ventricular fibrillation shockable?
yes - it’s not compatible with life & always pulseless
is monomorphic ventricular tachycardia shockable? how does it look on ECG?
yes - can be pulseless or “conscious”
on ECG - regular, broad complex tachycardia, monomorphic hence uniform QRS complexes within each lead
is polymorphic ventricular tachycardia shockable?
Polymorphic VT or torsades de pointes (twisting of the peaks)
- QRS complexes not uniform
- can be pulseless or pulse - if pulseless can deliver shock
what are the 4H’s and 4T’s - causes of cardiorespiratory arrest?
4H’s:
- hypoxia
- hypovolaemia
- hypothermia
- hyperkalaemia, hypokalaemia
4T’s:
- Tension pneumothorax
- Tamponade
- Toxins
- Thrombus
is asystole shockable?
no - non shockable - it’s just flat line on ECG
is sinus rhythm shockable?
If no pulse -> pulseless electrical activity (PEA)
Non-shockable
pulseless electrical activity - although conduction normal, no contraction is occurring (or not effectively)
what are signs of returns of spontaneous circulation (ROSC)?
- signs of life (respiratory effort, pulse)
- rise in ETCO2 (product of respiration)
what is the ongoing care you would provide for post cardiac arrest (once ROSC)?
- 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
when do you terminate CPR?
- 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
what are most important things to prevent cardiac arrest?
Early recognition AND intervention
what is ABCDE assessment?
A = airways
B = breathing
C = circulation
D = disability
E = exposure
what is A in ABCDE?
A = airway
- head tilt, chin lift (then jaw thrust & suction if needed)
- assess by talking, distressed breathing, see saw breathing, shortness of breath
what is B in ABCDE?
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
what is C in ABCDE?
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
what is D in ABCDE?
D = disability
- maintain normoglycaemia, reversal agents (BZD, opoids), seizure control, patient positioning
- assess by profound hypoxia, hypercapnia, hypoglycaemia, AVCPU, pupils, blood glucose, temp
what is E in ABCDE?
E = exposure
- differentials & ensure normothermia
- remove clothes to enable examinations for bleeding, injury, rashes - avoid heat loss & maintain dignity
