CPR – Cardiopulmonary Resuscitation / Basic Life Support (BLS)

CPR is a lifesaving procedure for a victim who has signs of cardiac arrest.

High quality CPR can improve the chance of survival in such patient.

Signs Of Cardiac Arrest
1. Unresponsiveness 
2. No normal breathing (Agonal respiration / apnoea)
3. No pulse 
High Quality CPR
1. Start compressions within 10 seconds of recognition of cardiac arrest. 
Push hard, push fast: Compress at a rate of 100 to 120/min with a depth of 
— At least 5 cm for adults 
— At least one third the depth of the chest, about 5 cm, for children 
— At least one third the depth of the chest, about 4 cm, for infants 
2. Allow complete chest recoil after each compression. 
3. Minimize interruptions in compressions (try to limit interruptions to less than 10 seconds). 
4. Give effective breaths that make the chest rise. 
5. Avoid excessive ventilation. 
Chest Compression Depth….
At least 5 cm for adults 
More than 6cm can cause injury
Personal protective equipment (PPE) helps to protect the rescuer from health or safety risks.
Adult Chain Of Survival

AHA has developed 2 distinct adult chains of survival, which are….
     In-hospital cardiac arrest (IHCA)
     Out-of-hospital cardiac arrest (OHCA)

In-Hospital Cardiac Arrest (IHCA)
The links in the Chain of Survival for an adult who has a cardiac arrest in the hospital are….
1. Surveillance, prevention, and treatment of prearrest conditions 
2. Immediate recognition of cardiac arrest and activation of the emergency response system 
3. Early CPR with an emphasis on chest compressions 
4. Rapid defibrillation 
5. Multidisciplinary post-cardiac arrest care (After ROSC)
These conditions are less likely to happen because of careful observation and early interventions.
Usually occurs due to respiratory or circulatory conditions.
Out-Of-Hospital Cardiac Arrest (OHCA)
The links in the Chain of Survival for an adult who has a cardiac arrest outside the hospital are…. 
1. Immediate recognition of cardiac arrest and activation of the emergency response system 
2. Early CPR with an emphasis on chest compressions 
3. Rapid defibrillation with an AED 
4. Effective advanced life support (Including rapid stabilization and transport to post-cardiac arrest care) 
5. Multidisciplinary post-cardiac arrest care (After ROSC)
Immediate recognition of cardiac arrest and activation of the emergency response system
First, recognize that the victim is in cardiac arrest based on….
Apnoea / Agonal respiration
No pulse

Activate the emergency response system or ask someone else to do it

Early CPR with an emphasis on chest compressions
Begin high-quality CPR without delay to improve the victim’s chance of survival

Bystanders who are not trained in CPR are encouraged to at least provide chest compressions (Guided by dispatchers over the telephone)

Rapid defibrillation with an AED
Rapid defibrillation + high-quality CPR, increases the survival chance by x2 or x3

Defibrillation with a manual defibrillator or AED as soon as the device is available

Effective advanced life support
Advanced life support (ALS) bridges the transition from BLS to more advanced care.
ALS can occur in any setting (both out of hospital and in hospital).
Effective ALS teams may provide the patient with additional care if needed, such as….
12-lead ECG
Electrical therapy interventions
Obtaining vascular access
Giving appropriate drugs

Placing an advanced airway

Multidisciplinary post-cardiac arrest care
(After ROSC)
Once ROSC is achieved, the next link is post-cardiac arrest care
Paediatric Chain Of Survival
Cardiac arrest is often secondary to respiratory failure and shock 


The links in the Chain of Survival for an paediatric patient who has cardiac arrest are…. 
1. Prevention of arrest 
2. Early high-quality bystander CPR 
3. Rapid activation of the emergency response system 
4. Effective advanced life support (Rapid stabilization and transport to post-cardiac arrest care) 
5. Integrated post-cardiac arrest care 
Sudden Cardiac Arrest Vs Heart Attack
Sudden Cardic Arrest
Heart Attack
1. Definition
It occurs when the heart develops an abnormal rhythm and cant pump blood
It occurs when the blood flow to part of the heart muscle is blocked
2. Presentation
Within seconds the patient become unresponsive and apnoeic
Death may occur within minutes if the victim does not receive immediate lifesaving medication
Severe chest pain / discomfort
Radiation to jaw, arms, back or neck
Shortness of breath
Cold sweats
Nausea, vomiting
* Heart attack rarely develop sudden cardiac arrest
* But heart attack is a common cause for sudden cardiac arrest 
Adult 1-Rescuer Sequence
1. Verify scene safety, check for responsiveness and get help
Verify that the scene is safe for you and the victim
Check for responsiveness – Tap the victim’s shoulder and shout, “Are you OK?” 
If the victim is not responsive, shout for nearby help
Activate the emergency response system
If you are alone, get the AED/defibrillator and emergency equipment. If someone else is available, send that person to get it
2. Assess for breathing and pulse 
To minimize delay in starting CPR, breathing and pulse should be assessed simultaneously 
Should no take more than 10 seconds 
Breathing : Check the rise of victims chest for not more than 10 seconds to detect apnoea / abnormal pattern of breathing   
Pulse : Palpate carotid pulse for not more than 10 seconds to detect absence of pulse 
Steps to check the carotid pulse 
a. Locate the trachea (on the side closest to you), using 2 or 3 fingers
b. Slide these 2 or 3 fingers into the groove between the trachea and the muscles at the side of the neck, where you can feel the carotid pulse 
c. Feel for a pulse for at least 5 but no more than 10 seconds. If you do not definitely feel a pulse, begin CPR, starting with chest compressions
3. Next step depends on breathing and pulse 
a. If breathing is normal and pulse present 
Monitoring of the victim 
b. If breathing is abnormal and pulse is present 
Confirm that emergency response system is active 
Begin rescue breathing 
Check pulse every 2 minutes 
Be ready to give high quality CPR if pulse become absent 
c. If breathing is abnormal and pulse is absent 
Begin high-quality CPR
4. High-quality CPR
Explained below 
5. Defibrillation with AED
Should be done as soon as it is available 
6. Resume high-quality CPR 
This is continued till advance life support arrives 
Adult Cardiac Arrest Algorithm

Components Of CPR
1. Chest compression 
2. Airway 
3. Breathing 
Chest Compression
Single rescuer should use the compression to ventilation ratio of 30 compressions to 2 breaths (30:2)
Chest compressions….
1. Compress at a rate of 100 – 120/min
2. Compress the chest at least 5cm 
3. Allow complete chest recoil after each compression
4. Minimize interruptions in compressions 
Compressions are given on a flat firm surface to increase the effectiveness
Chest compression technique….
a. Position yourself at the victim’s side
b. Make sure the victim is lying faceup on a firm, flat surface
c. Position your hands and body to perform chest compressions 
   Put the heel of one hand in the center of the chest, on the lower half of the sternum
   Put the heel of your other hand on top of the first hand 
   Straighten your arms and position your shoulders directly over your hands
d. Give chest compressions at a rate of 100 to 120/min. 
e. Press down at least 5 cm with each compression 
f. Allow the chest to recoil completely
g. Minimize interruptions of chest compressions



* Should avoid interruptions of chest compressions as much as possible as blood flow to the brain and heart will decrease significantly 
   It takes several compressions to increase the blood flow back to the brain and heart which was  present before the interruption
* Chest recoil allows the to flow into the heart
   Incomplete recoils reduces the filling of the heart
Opening The Airway
There are two methods to open the airway
1. Head tilt-chin lift
2. Jaw thrust 

If head neck injury is suspected – Use jaw thrust 
Each breath is given over one second, to make the victim’s chest rise 
Resume chest compression in less than 10 seconds 
Head Tilt-Chin Lift
Place one hand on the victim’s forehead and push with your palm to tilt the head back
Place the fingers of the other hand under the bony part of the lower jaw near the chin 
Lift the jaw to bring the chin forward
Jaw Thrust 
Place one hand on each side of the victim’s head. You may rest your elbows on the surface on which the victim is lying. 
Place your fingers under the angles of the victim’s lower jaw and lift with both hands, displacing the jaw forward
If the lips close, push the lower lip with your thumb to open the lips. 
Jaw thrust is used when head tilt – chin lift doesn’t work or a spinal / neck injury is suspected


Barrier devices such as pocket masks can be used to give rescue breaths 

There is low risk of infection from CPR


Oxygen content of the air we breath in is 21% 
Oxygen content of the air we breath out is 17% 

Bag-Mask Ventilation 
After head tilt-chin lift, bag-mask device can be used to give breaths to the victim 

In adult 2-Rescuer / Multiple Rescuer BLS



When giving compression, rescuers should switch compressors after every 5 cycles of CPR / every 2 minutes or sooner, if fatigue to ensure high quality CPR
The switch should take less then 5 seconds 
An AED analyzes the heart rhythm to identify the presence of a rhythm that responds to shock therapy (shockable rhythm). 
If VF or PVT is identified, the device prompts the delivery of an electrical shock to the heart. 
The shock temporarily “stuns” the heart muscle. 
This stops the VF or PVT and “resets” the electrical system of the heart, so a normal (organized) heart rhythm can return. If an organized rhythm returns and high-quality CPR continues, the heart muscle can begin to contract and pump blood effectively. 
If circulation returns, a pulse is palpable, and this is called return of spontaneous circulation (ROSC). 

Automated External Defibrillators (AED)
An automated external defibrillator (AED) is a lightweight, portable, computerized device that can identify an abnormal heart rhythm that needs a shock. 
The AED can then deliver a shock that can stop the abnormal rhythm (ventricular fibrillation or pulseless ventricular tachycardia) and allow the heart’s normal rhythm to return. 
AEDs are simple to operate, allowing laypersons and healthcare providers to attempt defibrillation safely
Defibrillation is used in….
Ventricular fibrillation
Pulseless ventricular tachycardia
To make it more effective the time interval between compression and shock delivery has to be kept minimal 
Life Threatening Arrhythmias
1. Ventricular fibrillation
2. Pulseless ventricular tachycardia
Procedure Of Using AED
1. Open the case and power on the AED
2. Attach the pads – Adults pads for victims of 8 years or above 
3. Allow AED to analyze the rhythm 
4. If its a shockable rhythm 
Clear the victim – Say loudly “Everybody clear”
Look to confirm that no one is in contact with the victim 
Delivery the shock – It will produce a sudden contraction of the victim’s muscles 
Immediately after delivering a shock, resume CPR, by chest compression
5. If its not a shockable rhythm 
Immediately resume CPR, by chest compression
5. After about 5 cycles or 2 minutes of CPR, the AED will prompt to repeat another shock 
AED Pad Placement
1. Anteolateral placement 
One pad directly below the right collarbone 
Other pad to the side of the left nipple with the top edge of the pad few centimeters below the armpit 
2. Anteroposterior placement 
One pad on the left side of the chest, between the victim’s left side of the sternum and left nipple 
Other pad on the left side of the victim’s back, next to the spine 
* Child pads should be used when giving defibrillation for a child < 8 years of age 

Team Dynamics


BLS For Children and Infants

Children – From 1 year to age of puberty 
Infants – Less than one year (Excluding newly born)
Signs Of Poor Perfusion
1. Cold extremities
2. Altered mental state (Decline in consciousness / responsiveness)
3. Weak pulses
4. Skin – Pale, mottling and later cyanosis
Pulse is checked….
Children : Carotid or femoral pulse
Infants : Brachial pulse 
Locating brachial artery in infants 
Place 2 or 3 fingers on the inside of the upper arm, midway between the infant’s elbow and shoulder
Locating femoral artery in children 
Place 2 fingers in the inner thigh, midway between the hipbone and the pubic bone and just below the crease where the leg meets the torso 
Chest compression
Infant : 2 finger chest compressions
Children : 1 or 2 hands 
Rate of chest compression 
For 1-rescuer BLS, the ratio is 30:2
For 2-rescuer BLS, the ratio is 15:2 (For both child and infants)
Depth of chest compression
1/3rd of the anteroposterior diameter of the chest
Infant : About 4 cm 
Children : About 5 cm   

Breathing techniques for infants
1. Mouth to mouth
2. Mouth to mouth and nose 

Paediatric Cardiac Arrest Algorithm For 1-Rescuer

Paediatric Cardiac Arrest Algorithm For 2 Or More Rescuers



Summary Of High-Quality CPR For BLS Providers
Latest posts by Dr. Pasindu Suriapperuma (see all)
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1 year ago

It was very useful. Thank you 😘

1 year ago

It was very useful. Thank you 😘