Using Electronically Captured Data to Provide Feedback to Rescuers

Newer monitor/defibrillators may allow documentation of real-time CPR quality indicators including compression rate and depth (when used with an accelerometer), ventilation rate, endtidal CO2 values, and hands-off time throughout the resuscitation (CPR fraction), including pauses for defibrillation. Some systems are able to use voice recordings in combination with electronic data recordings which allows precise documentation of all activities as they occur during the resuscitation.

Data downloaded from monitor/defibrillators can be viewed and analyzed using programs available from the monitor vendor. These programs allow capture, review, and analysis of electronic ECG recordings after they are downloaded from the monitor/defibrillator following a cardiac arrest. Once the ECG file is uploaded into the program, key components of the arrest such as number and timing of defibrillations, pauses in care, CPR fraction, and ventilation ratios can be visualized and quantified. Some programs allow additional data entry in a registry style and will incorporate the ECG file and the CPR metrics as well as provide summary reports of the case.

Examples of some of these programs can be found at the following web sites:


Use of these technologies allows a timely review of CPR metrics with the rescuers. They are useful to quantify interruptions in chest compressions which are frequently encountered while waiting for the defibrillator to charge, and after a shock, when changing rescuers, or when providing other interventions such as intubation or IV placement. Addressing all sources of pauses during a complete review of the case using these available tools can highlight areas for improvement.

While new technologies help us to understand the overall quality of the resuscitation, there are few, if any, controlled studies to inform the precise value of each component. In the near future, as the literature in this field grows, it will be evaluated and translated into informed guidelines to help in decision making regarding technology investments for individual systems.

Among the American Heart Association’s 2010 Guidelines for CPR and ECC, there is a new recommendation which states “Resuscitation systems should establish ongoing systems of care assessment and improvement.” The rational from the AHA on this topic focuses around the lack of understanding about the causes of such extremely divergent regional variation in both the incidence and outcome for SCA. A plea is made for both EMS systems and hospitals to systematically monitor cardiac arrests and outcome and to employ quality improvement measures including feedback, and benchmarking in order to improve performance.



Benchmarking of SCA survival should be performed internally, using comparisons to prior performance on an annual basis, and externally comparing the system’s survival rates to those of similar systems. Ensure that your measurements are made using the standard case definition, and that the other systems, to which you will be compared, use the same standard case definition. Benchmarking results should be shared with all stakeholders in your community.

Because so many factors influence survival outcomes in an EMS system, it is challenging to determine precisely how each affects the resuscitation care process and how they may influence survival in your community. If your system is just beginning to systematically improve SCA survival, take care NOT to benchmark your system immediately against systems like Seattle and Rochester that have reached their excellent survival rates by making incremental improvements steadily for decades. Although these organized and dedicated systems have pushed their survival for witnessed VF cases near to 50%,15 resuscitation experts agree that improving survival is an iterative process. Any improvements over your systems baseline survival rates will result in additional survivors each year, and will serve as a stepping stone to the next improvement.