Hands-Only cardiopulmonary resuscitation (CPR) is a simplified emergency procedure focusing solely on continuous chest compressions for a person experiencing sudden cardiac arrest. This technique is designed as a quick, immediate intervention performed by a bystander while professional medical help is on the way.
The Core Purpose of Hands-Only CPR
The core objective of Hands-Only CPR is to maintain blood circulation to the body’s most sensitive organs, particularly the brain and the heart. When cardiac arrest occurs, the heart stops pumping effectively, halting the flow of oxygenated blood. Without this flow, brain cells begin to die rapidly, often within four to six minutes.
Starting compressions right away pushes blood through the circulatory system, delaying irreversible damage. This sustains the viability of the brain and heart muscle until emergency medical services (EMS) arrive with advanced life support equipment. Hands-Only CPR is effective in the first few minutes because the victim’s blood still contains residual oxygen that can be circulated. The technique buys time, significantly increasing the chance of survival compared to receiving no aid.
Recognizing When to Use Hands-Only CPR
Hands-Only CPR is intended for adults who are unresponsive. The first step for any bystander is to quickly assess the scene for safety and then check the person for responsiveness by tapping and shouting. If the adult does not respond and is either not breathing or only gasping, they are likely experiencing sudden cardiac arrest.
The primary action before starting compressions is to call 911 or the local emergency number immediately, or instruct another bystander to do so. Activating EMS ensures professional help is dispatched quickly, providing the highest level of care. Once the call is made, the bystander should immediately begin providing chest compressions.
The Physiological Mechanism of Chest Compressions
Pushing on the chest creates the pressure needed to move blood throughout the body. When a rescuer pushes down in the center of the chest, the heart is squeezed between the sternum (breastbone) and the spine. This compression forces blood out of the heart’s ventricles and into the major arteries, generating circulation.
This mechanism is referred to as the cardiac pump theory, simulating the heart’s normal function. The subsequent release of pressure, or recoil, allows the chest to return to its normal position, creating negative pressure that lets the heart chambers refill with blood from the veins. Compressions should be performed at a rate of 100 to 120 times per minute and a depth of about two inches to ensure effective blood movement.
Why Hands-Only CPR Is Recommended for Lay Rescuers
Hands-Only CPR is promoted for lay rescuers because it removes the psychological and technical barriers associated with conventional CPR. Eliminating rescue breaths simplifies the technique to two steps: calling 911 and pushing hard and fast on the chest. Many individuals hesitate to perform mouth-to-mouth resuscitation due to lack of training or concerns about infection, often leading them to do nothing.
This simpler approach increases the confidence and willingness of bystanders to intervene immediately. Since immediate action leads to a better outcome in adult sudden cardiac arrest, increased bystander intervention outweighs the omission of rescue breaths in the first few minutes. Focusing on continuous, high-quality compressions with minimal interruptions maximizes blood flow, offering the best chance of survival until medical professionals arrive.