CPR Flashcards
What is ROSC?
Return of spontaneous circulation
What is the in-hospital mortality of patients who survive a cardiac arrest?
71%
What is post-cardiac arrest syndrome?
AKA post-resucitation syndrome
Occurs following ROSC following cardiorespiratory arrest, involves multiple systems
Severity depends on the duration and cause of cardiac arrest
Causes of death following cardiac arrest
Early: due to cardiovascular intability
Late: brain injury (most common), multi organ failure and sepsis
Mechanism of post-cardiac arrest syndrome
Thought to be due to production of free radicals during hypoxia
🧠 1. Brain injury: ischaemia or hyperaemia due to micro and macro circulatory compromise
🫀 2. Myocardial dysfunction: hypokinesis occurs aka myocardial stunning, decreased heart wall motion
- Ischaemia/ reperfusion response: release of inflammatory cytokines
- Persistent precipitating pathology: the cause of the cardiac arrest continues to impact on physiological parameters
Management following ROSC
A-E
A: if patient not waking 10-15mins after ROSC then intubate
B: maintain sats 94-98%
C: aim for MAP 65-100 and use arterial line to continually monitor
D: record GCS before any sedation, control seizures (they cause metabolism to be 3x which quickly causes hypoxia)
E: control temp
G: glucose: avoid hypoglycaemia
Identify and treat underlying pathology
Discuss post-cardiac arrest hypothermia
Mild hypohtermia may suppress chemical reactions associated with reperfusion injury following arrest
There is some evidence that all survivors of cardiac arrest benefit from mild hypothermia
ALS group recommend cooling the patient to 32-34 degrees for 12-24hrs after an out of hospital arrest but evidence is mixed
Pyrexia must be prohibited after arrest
Clinical features of cardiac arrest
Suspect in any patient who is unconscious and does not have signs of life
Pulse: check for a central pulse for no more than 10s
> Other confirmatory clinical features e.g. colour, pupil size or response waste time and do not help
Respiratory efforts may persist for several mins after arrest
Information to obtain from ambulance crew/ relatives
Patient details: age, PMHx, current medication, chest pain before event
Time of collapse, 999 call, start of CPR, first defib shock, other management and ROSC
Any bystander CPR?
Discuss the team in a cardiac arrest case
Hospital will have be pre-alerted by ambulance and therefore team ready in resus with equipment needed
Team leader: controls and coordinates the CPR
4-6 team members is optimal
Each member should know role
Perform CPR with minimal interruption unless when using defib
What to do when encountering a collapsed or sick patient?
Call for help
Assess patient
Signs of life?
Yes: assess A-E, recognise and treat, call resus team if needed
No: call resus team, CPR 30:2, apply defib and assess rhythm, shock if appropriate, ALS when tram arrives
How long should each breath last when giving CPR?
~1s
Rate of chest compressions
100-120/min
How far away from a pacemaker should a defib pad be?
>15cm
How long, after giving a defib shock, should we continue CPR before checking rhythm?
2 mins
What can be done for patients in a shockable rhythm when a defib is not immediately available?
Precordial thump: tighly clench fist and give one direct blow from 20cm to the lower 1/2 of the sternum
How can we confirm correct tracheal tube placement?
End tidal CO2 - partial pressure of CO2 at the end of an exhaled breath
Detected by a sensor located between the patients airway and the ventilator
Routes of drug administration in cardiac arrest
Peripheral cannula: useful to flush the drug through with saline and elevate the limb when given
Central venous cannulation isn’t recommended because its time consuming, tricky and interrupts CPR
Intra-osseus infusion is also an option
Not recommended to put drugs down ET tube or to give intracardiac injections
Drug of choice in cardiac arrest
Adrenaline
Given after 3 shocks in VF or pulseless VT
Given immediately in asystole/ PEA
What is PEA?
Pulseless electrical activity
The clinical situation of cardiac arrest with an ECG trace compatible with a cardiac output
What can cause PEA?
Failure of the pump:
- MI, drugs e.g. b-blockers/ calcium antagonists, electrolyte disturbances e.g.hypo/hyperkalaemia
Obstruction to cardiac filling or output:
- Tension pneumothorax (compresses heart and prevents filling), tamponade, myocardial rupture, PE, prosthetic valve occlusion, hypovolaemia
How long do we do CPR for?
Depends on the situation, time since onset and estimated prospect of survival
Generally: always continue whilst patient is in a shockable rhythm, try changing pad position if repeated defib attempts do not work
Asystole lasting >1hr is rarely associated with survival
>>> exceptions being asystole in the young, hypothermia, near drowning and drug overdose <<<
ALS CPR algorithm revision
What should be given to patients in torsades de pointes and refractory VF due to digoxin toxicity or hypomagnesaemia?
Magnesium sulfate
Which vessels are used for central venous access?
Internal jugular and subclavian veins
Risk of subclavian cannulation is pneumothorax so jugular is preferred
USS guidance is used, right side of neck is ideal as less risk of thoracic duct damage
Femoral vein is used for temporary access in severe trauma and burns
