A chest compression feedback device is a tool used during cardiopulmonary resuscitation (CPR) to measure and evaluate the quality of a rescuer’s technique. These devices utilize sensors and accelerometers to monitor the physical mechanics of compressions, providing objective, real-time data. The goal is to ensure rescuers adhere to established resuscitation guidelines, such as those from the American Heart Association, which focus on delivering high-quality compressions. By providing immediate guidance, the device helps maintain consistent and effective circulation until professional medical help can take over.
Compression Rate Metrics
The device closely tracks the speed at which compressions are delivered, measuring the number of compressions per minute (CPM). Current resuscitation guidelines emphasize maintaining a rate between 100 and 120 compressions per minute for adults. Staying within this specific speed range dictates the pace at which blood is circulated throughout the body.
A rate slower than 100 CPM may not generate enough blood flow to vital organs. Conversely, delivering compressions faster than 120 CPM can become counterproductive, potentially leading to incomplete chest filling between pushes. This consistent timing helps the artificial pumping action simulate the heart’s function most effectively.
Compression Depth Metrics
Compression depth is measured by the physical distance the chest wall is pushed down during each press. For adults, the device monitors to ensure the depth is at least 2 inches (5 centimeters) but not more than 2.4 inches (6 centimeters). Achieving this precise depth determines the pressure applied to the heart, which is situated between the sternum and the spine.
If compressions are too shallow, insufficient pressure is created, and not enough blood moves to sustain the brain and organs. Pushing deeper than the recommended 2.4 inches can raise the risk of injury, such as rib fractures or damage to internal organs. The device provides feedback to help the rescuer balance achieving adequate circulation and preventing excessive force.
Monitoring Chest Recoil
The feedback device also monitors chest recoil, which is the complete return of the chest wall to its normal, resting position after each compression. This metric is tracked to ensure that the rescuer is not leaning on the chest between pushes. Full recoil is necessary because it creates a vacuum-like effect, or negative intrathoracic pressure, inside the chest cavity.
This negative pressure allows the heart’s chambers to fully refill with blood from the veins before the next compression occurs. Incomplete recoil, often called “leaning,” limits the amount of blood that can flow back into the heart. If the heart does not refill properly, the subsequent compression will pump a reduced volume of blood, diminishing the overall effectiveness of the CPR effort.
How Real-Time Feedback Is Delivered
Based on the data collected on rate, depth, and recoil, the device provides immediate, actionable guidance to the rescuer. This feedback is typically delivered through a combination of auditory and visual cues designed to facilitate instant correction of technique. Visual feedback often includes an LED light bar or a screen display that changes color or position to indicate if the current metric is within the acceptable range.
Auditory cues are common, such as a metronome-like clicking sound to help maintain the correct rate. The device might also provide verbal prompts, such as “push harder” for shallow compressions, or signal an alert if the rescuer is leaning. This instant, objective information allows the rescuer to adjust their performance on the spot, improving the quality of the resuscitation attempt without delay.