How to perform a CPR

C.P.R. AND CEREBRAL PROTECTION

Definition: Cardiopulmonary Resuscitation 

Includes: Basic Life Support (B.L.S.) and Advanced Cardiac Life Support (A.C.L.S.) 

All part of a spectrum of Emergency Cardiac Care (E.C.C 

Basic Life Support 

1. Improves survival following cardiac  arrest 

2. Supports circulation +/- respiration when arrest has already occurred
3. Includes Defibrillation 

Advanced Cardiac Life Support

BLS + use of drugs/equipment to: 

1. Support airway/ventilation 
2. Establish intravenous access 
3. Give drugs 
4. Monitor 
5. Control arrhythmias 

Goal of Resuscitation 

• Return of victim to pre-arrest quality of life
• Return to pre-arrest state of health

Chain of Survival 

• 5 critical interventions 
• Not done or delayed => death 
• Called the “Chain or Survival” 

1. Early Access 

• Recognition: Collapse, unresponsiveness, arrested state
• Rapid arrival of help

2. Early Cardiopulmonary Resuscitation 

• The nearer to time of collapse resuscitation begins, the more effective

3. Early Defibrillation 

• Includes Automated External Defibrillator (A.E.D.)

4. Early advanced care

• Access to drugs  and trained medical staff

5. Integrated Post-arrest care

• Access to multidisciplinary intensive care, coronary reperfusion facilities etc 

Time!

4min – brain damage begins

4 – 6 min – brain damage likely

6min – brain damage certain 

Prevention better than cure! 

Unstable Patient (Pre-arrest) 

• Pallor
• Sweating
• Cold, clammy extremities
• Impaired consciousness
• Hypotension (Sys <90)
• Chest pain

Unstable Patient – 1^st steps
  

1. Oxygen
2. I.V. access
3. 12 lead E.C.G. (if possible)
4. Electrolytes – Correct

Arrhythmias 

1. Brady arrhythmias 

• HR < 60
• Absolute bradycardia HR < 40
• Unstable?
  1. Sys BP < 90 mmHg
  2. HR < 40
  3. Ventricular arrhythmias 
  4. CCF 
• Sequence for Brady arrhythmias 

2. Tachyarrhythmias (with pulse) 

C.P.R. 

Definition:

• A series of actions performed on a victim of cardiac arrest that improve the chances of survival 
• 1^st published use of chest compressions 1960 – 14 survivors 

JAMA 1960; 173:1064-67

• 1^st use of defibrillator – 1962
• 1^st published CPR guidelines – 1966 

C.P.R. Today 

•  MAIN EMPHASIS 
• High quality Chest Compressions
  • Adequate rate and depth
  • Complete recoil of chest wall
  • Minimal interruptions
• Avoid excessive ventilation
• Post CPR care 
• A.B.C. to C.A.B. 

Reasons :

1. Most survivors
   1. VF & pulseless VT
   2. Witnessed arrest
2. Delay of chest compressions  => reduced survival
3. Airway control (Intubation) => greater level of ‘competence’ => delay 

Cerebral Protection  (Post-resuscitation) 

1. Mechanisms of Cerebral injury
   1. Cerebral ischaemia 
      • Failure of ion/energy pumps at cellular level
      • Release of free radicals
      • Reperfusion injury -> Release of inflammatory mediators:
        • Leucotriene B
        • Arachidonic acid
        • Heat-shock protein 
2. Cerebral Protection 
   1. Cooling – blunts cerebral ischaemic injury
   2. Normoglycaemia 
   3. Avoid hyperoxia 
   4. Barbiturate coma 

Specific actions – Early CPR: 

Recognition of arrest 

1. Immediate recognition of arrest and activation of emergency response system
   • Unresponsive
   • Not breathing or gasping
2. Chest Compressions 

• Rate – 100/min
• Depth – 5cm
• Complete chest wall recoil in-between
• Rotate person compressing every 2mts
• Minimal interruptions – maximum 10 seconds 

Patient position for adequate chest compressions

1. Patient horizontal & supine
2. Head level or lower than heart
3. Firm backboard

3. Airway 
   • Head tilt/chin lift
   • Jaw thrust – cervical spine injury
   • If untrained in airway control – ‘Hands Only’ CPR
   • Airway more important in asphyxial causes of arrest e.g. drowning and in children 
4. Breathing 

CPR

• Ratio of compression:ventilation  30:2

• After advanced airway:
  • Independent compressions 100/min
  • Independent ventilation 10/min 
• Early Defibrillation 
• Once arrest recognized, collect AED/Defibrillator or send helper
• Defibrillation should not interrupt chest compressions for more than 10seconds
• Defibrillation more effective with quality chest compressions
• Defibrillation the key intervention for VF and pulseless VT 

Types of Cardiac Arrest 

• Cardiac arrest associated with 2 groups of arrhythmias:
  • Shockable 
    • VF
    • VT
  • Non-shockable 
    • Asystole 
    • PEA

Sequence of actions 

Shockable Rhythms (VF/VT) 

• For a patient coming in with unwitnessed arrest, CPR  for 2min, then defibrillation
• For in-hospital or witnessed arrest, immediate defibrillation 
• Attempt defibrillation
  • One shock
  • CPR x 2min
  • Check rhythm (<10sec)
• VF/VT persists
  • 2^nd shock
  • CPR x 2min
  • Check rhythm
• VF/VT persists
  • Adrenaline 1mg
  • 3^rd shock
  • CPR x2min
  • Check rhythm
  • VF/VT persists
  • Amiodarone 300mg
  • 4^th shock
  • CPR x2min
  • Check rhythm
• VF/VT persists
  • Adrenaline 1mg
  • Shock
  • CPR x2min
  • Check rhythm
  • Repeat sequence of Shock, CPR, rhythm, check. Give Adrenaline 1mg after every alternate shock/CPR sequence 
• If organised electrical activity seen during rhythm check, feel for pulse
  • Pulse present, post-resuscitation care
  • Pulse absent, resuscitate as for non-shockable rhythm
  • If Asystole, continue resuscitation as for non-shockable rhythm 

Non-shockable Rhythms (Asystole/PEA) 

PEA , Asystole & Slow PEA 

• CPR 30:2
• Adrenaline 1mg as soon as i.v. access achieved
• Atropine 3mg only in asystole and slow PEA (<60/min)
• CPR 30:2 until airway secured
• Once airway secured
  • Chest compressions are continuous 
  • Ventilation independent at 10 breaths per min 
• Recheck rhythm after 2 min
• If no change
  • Continue CPR
  • Recheck rhythm ever 2 min
  • Give adrenaline 1mg iv every 3 – 5 min
• If organised activity seen on ECG, check pulse
• Pulse
  • Post resuscitation care
• No pulse
  • Continue CPR, rhythm check, adrenaline cycle
• If VF or VT occurs switch to shockable rhythm sequence 

As CPR goes on, remember to treat cause of arrest, if possible…
4Hs & 4Ts

The 4Hs

• Hypoxia
• Hypovolaemia 
• Hyperkalaemia, hypokalaemia, hypocalcaemia, acidaemia, other metabolic disorders
• Hypothermia 

The 4Ts

• Tension pneumothorax 
• Tamponade 
• Toxic substances
• Thromboembolism (PE/MI) 

Summary 

• CPR includes basic and advance life support
• Time is of essence in successful management of arrest
• Aim is to return patient to pre-arrest state through implementing “chain of survival”
• Recognition of pre-arrest rhythms key to preventing arrest
• Emphasis is on chest compressions, judicious ventilation, post CPR cerebral protection
• Proper sequencing important
• Treat possible causes as CPR goes on