Research prospects
The feature opens multiple avenues for future research. Acquiring data by this method should be simple for any facility using LIFEPAK 20/20e defibrillators as its standard devices. Matching the existing handwritten code records with the time intervals obtained using this surrogate time marker will show how inaccurate the commonly reported data are. This can be done with a retrospective study comparing the time intervals from the archived event records with those from the handwritten records, to provide an example of the inaccuracy of data reported in the medical literature. The more accurate picture of time intervals can provide a much-needed yardstick for future research aimed at shortening response times.
The feature can facilitate aggregation of data across multiple facilities that use the LIFEPAK 20/20e as their standard defibrillator. Also, it is possible that other defibrillator manufacturers will duplicate this feature with their devices – it should produce valid data with any defibrillator – although there may be legal and technical obstacles to adopting it.
Combining data from multiple sites might lead to an important contribution to resuscitation research: a reasonably accurate overall survival curve for in-hospital tachyarrhythmic arrests. A commonly cited but crude guideline is that survival from tachyarrhythmic arrests decreases by 10%-15% per minute as defibrillation is delayed,10 but it seems unlikely that the relationship would be linear: Experience and the literature suggest that survival drops very quickly in the first few minutes, flattening out as elapsed time after arrest increases. Aggregating the much more accurate time-interval data from multiple facilities should produce a survival curve for in-hospital tachyarrhythmic arrests that comes much closer to reality.
Conclusion
It is unknown whether this feature will be used to improve the accuracy of reported code response times. It greatly facilitates acquiring more accurate times, but the task has never been especially difficult – particularly when balanced with the importance of better time data for QI and research.8 One possible impediment may be institutional obstacles to publishing studies with accurate response times due to concerns about public relations or legal exposure: The more accurate times will almost certainly be longer than those generally reported.
As was stated almost 2 decades ago and remains true today, acquiring accurate time-interval data is “the key to future high-quality research.”2 It is also key to improving any hospital’s quality of code response. As described in this article, better time data can easily be acquired. It is time for this important problem to be recognized and remedied.
Mr. Stewart has worked as a hospital nurse in Seattle for many years, and has numerous publications to his credit related to resuscitation issues. You can contact him at [email protected].
References
1. Kaye W et al. When minutes count – the fallacy of accurate time documentation during in-hospital resuscitation. Resuscitation. 2005;65(3):285-90.
2. The American Heart Association in collaboration with the International Liaison Committee on Resuscitation. Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care, Part 4: the automated external defibrillator: key link in the chain of survival. Circulation. 2000;102(8 Suppl):I-60-76.
3. Chan PS et al. American Heart Association National Registry of Cardiopulmonary Resuscitation Investigators. Delayed time to defibrillation after in-hospital cardiac arrest. N Engl J Med. 2008 Jan 3;358(1):9-17. doi: 10.1056/NEJMoa0706467.
4. Hunt EA et al. Simulation of in-hospital pediatric medical emergencies and cardiopulmonary arrests: Highlighting the importance of the first 5 minutes. Pediatrics. 2008;121(1):e34-e43. doi: 10.1542/peds.2007-0029.
5. Reeson M et al. Defibrillator design and usability may be impeding timely defibrillation. Comm J Qual Patient Saf. 2018 Sep;44(9):536-544. doi: 10.1016/j.jcjq.2018.01.005.
6. Hunt EA et al. American Heart Association’s Get With The Guidelines – Resuscitation Investigators. Association between time to defibrillation and survival in pediatric in-hospital cardiac arrest with a first documented shockable rhythm JAMA Netw Open. 2018;1(5):e182643. doi: 10.1001/jamanetworkopen.2018.2643.
7. Cummins RO et al. Recommended guidelines for reviewing, reporting, and conducting research on in-hospital resuscitation: the in-hospital “Utstein” style. Circulation. 1997;95:2213-39.
8. Stewart JA. Determining accurate call-to-shock times is easy. Resuscitation. 2005 Oct;67(1):150-1.
9. In infrequent cases, the code cart and defibrillator may be moved to a deteriorating patient before a full arrest. Such occurrences should be analyzed separately or excluded from analysis.
10. Valenzuela TD et al. Estimating effectiveness of cardiac arrest interventions: a logistic regression survival model. Circulation. 1997;96(10):3308-13. doi: 10.1161/01.cir.96.10.3308.