CPR Quality Improves Survival
Q&A with Dr. Ben Bobrow and Dr. Graham Nichol
On June 30, Dr. Ben Bobrow of the University of Arizona, who chairs the American Heart Association’s BLS Subcommittee and served as guest editor of the JEMS supplement, CPR Performance Counts, and Dr. Graham Nichol of the University of Washington focused on the latest resuscitation science and the evolution of the 2010 AHA Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Guidelines in our webcast, CPR Quality Improves Survival. During the presentation, they were able to answer only a few questions. Below are answers to additional questions posed by the participants:
Q: When you say to activate the emergency response system, how far do you go? If you're alone, do you just yell for help? I've had some students ask if they can they use their cell phone, dial 9-1-1, turn on speaker mode and talk while they're giving compressions.
A: You should activate the emergency response system by whatever means is available while still initiating CPR for the patient. If a cell phone is available, turning on the handsfree speaker is a good strategy.
Q: Can you explain the ACLS recommendation about the use of adenosine for wide complex tachycardia (monomorphic)? Is this in case it's a supraventricular beat with conduction delay?
A: Here is the link to the AHA Guideline discussion of adenosine for wide complex tachycardia: http://circ.ahajournals.org/cgi/reprint/122/18_suppl_3/S729
Q: Is there any data showing the survival rates with paramedic care vs. EMT care?
A: Likely paramedic care is important, although the core of resuscitation care involves BLS and early defibrillation. So if a community has only BLS available, they can still have an effective system of cardiac resuscitation care and save lives.
Q: Can capnography be a factor in survival rates if it’s being used in areas where survival is higher?
A: Capnography is a tool that can help guide the quality of CPR, which may impact survival.
Q: Any comment on the use of capnography as a measure of viability to continue CPR (recent Mayo 96-minute resuscitation)?
Related Question: Is a CO2 capnometer beneficial for a patient intubated with a CombiTube?
A: When quantitative waveform capnography is used for adults, the Guidelines now include recommendations for monitoring CPR quality and detecting ROSC based on PETCO2 values.
Q: Where's the evidence you speak of regarding identifying which cities are doing well and which are doing poorly with survival rates?
A: Check out the following study: Nichol G, Thomas E, Callaway CW, et al. Resuscitation Outcomes Consortium Investigators. Regional variation in out-of-hospital cardiac arrest incidence and outcome. JAMA. Sept.24, 2008;300(12):1423–1431. http://jama.ama-assn.org/content/300/12/1423.full.pdf
Q: How do other interventions contribute to ROSC and survival -- namely post cardiac arrest hypothermia, intubations, therapeutics administered -- and how are these interventions separated from the 500% difference?
A: Each of the links in the chain of survival is cumulatively reflected in the survival rate for communities. It is challenging to separate out individual interventions.
Q: How can you implement a system, like in Seattle, where every high school senior is trained in CPR?
A: The Seattle and King County systems focus on strengthening and measuring the entire chain of survival, including community CPR training. They have done this consistently for several decades. Some states also have standards for school CPR training. You could check with your Alabama statutes.
Q: What is considered the benchmark tool for measuring CPR quality?
A: The important components of CPR quality are defined in the Guidelines (CC rate, depth, recoil, interruptions, and ventilation), but the benchmark for achieving CPR quality is not well defined. Electronic CPR feedback devices can be helpful to guide providers during CPR, but they are not yet considered the "benchmark."
Q: How long does it take for CPP to ramp back up? You have to pause for certain aspects of patient care. If you can give 10-15 seconds of compressions between, does it impact CPP?
A: The time to ramp CPP up likely depends on the quality of CPR. The CPP does fall during a 15-second pause in compressions and we know from the recent ROC study that a 20-second pause is associated with worse survival from OHCA.
Q: Do we know that passive O2 via non-rebreather mask is inferior to bagging the patient via endotracheal tube, even if the patient isn't hyperventilated?
A: The optimal method of ventilation and amount of oxygen during resuscitation are still being defined. Not interrupting CPR for prolonged periods of time for advanced airway placement and not providing excessive ventilation are important.
Q: Could trained rescuers just put a pulse oximeter to the patient instead of feeling for a pulse?
A: Using a pulse oximeter to determine if a patient has a pulse would likely delay the initiation of CPR, which is not recommended. Checking for responsiveness and normal breathing are more rapid methods to determine the need for CPR. Remember that the harm lies in not providing CPR, not in initiating CPR on a patient who ends up not being in cardiac arrest.
Q: Are manual CPR devices beneficial? I recall the Thumper from earlier parts of my career, which fell out of favor.
A: Mechanical CPR devices are being actively studied, and we should have more science on this topic soon. Some of the current mechanical CPR devices work under the same cardiac compression principle as the "Thumper," and some work differently, under what is called the thoracic compression principle.
Q: What do you think of the mechanical CPR devices available? What rate and depth would you want them to go at?
A: Until we have more science to determine other optimal ranges for CPR, the current "at least 2 inches" and at least 100 compressions/min" would be the recommendations.
Q: How have you addressed the hesitation of some professionals to have the audio feedback system turned on at a scene due to a patient's family/bystanders possibly hearing that the crew is not doing CPR properly?
A: The devices are designed so that providers are able to turn down the audio feedback system on scene. However the visual feedback is still available.
Q: Presuming 100 compressions per minute at correct depth and without ventilation, how long before blood flow is considered de-oxygenated?
A: This is an important question that is debated. Adults with cardiac etiology arrests likely have oxygen stores for at least 5-10 minutes and maybe longer.
Q: Is there a standard data set that EMS providers can use so we can compare our community to others?
A: Look at the Utstein template for the core of data elements and data definitions to collect and measure.
Q: When a shock results in ROSC, the AHA guidelines still specify 2 minutes of CPR because the heart is weak and can return to V-fib. If you are using a monitor or ZOLL AED with ECG display, should you try to sync your compressions with the patient’s heart rate, or just stay with an unsynchronized 100/min?
A: This is an interesting question. I think it would be very challenging to coordinate compressions with the ECG display (often a lot of ectopy after defibrillation), but theoretically this would make sense to help "augment" the underlying hearth rhythm. Regardless, this is only for 2 minutes when providers should check for pulse and signs of life (purposeful movement).
Q: Can you please explain the acronym ROSC and what it means?
A: ROSC stands for return of spontaneous circulation and basically means the patient has regained their heartbeat.
Q: OK, so we know what our cardiac arrest rates are in our area. We know how many we transport, but we don't know their outcomes. We are currently working to gather outcome data, but our difficulty lies in cooperation from hospitals in sharing their data with us.
A: You should continue to work with your local hospitals and show them that this is part of your system’s QI program, and thus the protected health information is HIPAA-exempt.
Q: Are you advocating standard CPR for EMS rescuers rather than continuous compressions? If CCC CPR is your recommendation, is it ever appropriate to provide positive pressure ventilations without an advanced airway? Also, for how long should CCC CPR be done before starting 30:2 standard CPR?
A: We are not advocating one method over another.
Q: What are your thoughts on drips after ROSC from VF/pulseless VT? Some systems still have this in protocol although the 2010 guidelines don’t really address drips (e.g., lidocaine/amiodarone).
A: There is insufficient evidence to recommend a specific timing or sequence (order) of drug administration and advanced airway placement during cardiac arrest. In most cases, the timing and sequence of these secondary interventions will depend on the number of providers participating in the resuscitation and their skill levels. Moreover, the 2010 algorithms are much simplified compared to 2005. Finally, there is insufficient evidence to recommend a specific sequence of post-resuscitation infusions. Practically, you might consider using whatever is available and worked. For example, if the patient converted with lidocaine, start a lidocaine infusion. Ditto for amiodarone.
Q: Are there any changes regarding when to terminate prehospital care for non-ROSC arrests?
A: There are no large changes in when to terminate care in the field. However, many regions have noted less need to do so as they measure and improve CPR.
Q: What are your thoughts on the order of management for sympathetic bradycardia? There’s no real order given in the Guidelines. Atropine. dopamine/epi drips, and TCP all are discussed. Is there a better modality than another?
A: No particular order was stated because there is no demonstrated benefit of one of these treatments over another. Part of the answer will depend on which intervention is most quickly available. Usually, this will be atropine then drop, then TCP.
Q: Why no atropine? Isn't it a vagolytic? Is it being assumed that the vagus nerve is NOT involved in PEA or asystole?
A: You are correct. Atropine is no longer recommended in patients with PEA or asystole because there is no evidence that it is beneficial in this population.
Q: VF as a proportion of cardiac arrest cases has fallen. How come?
A: That is a good question. We do not know the precise answer, but it is likely due largely to the benefits of primary and secondary prevention of heart disease.
Q: Hands-only CPR is touted as being only for witnessed adult arrest but it is the general consensus that it should/could be applied to all ages as SOME CPR is better than NO CPR. Granted pediatrics need respiratory support more than adults, but again, some is better than none? What say you?
A: Unwitnessed arrest is less likely to be in a shockable rhythm; children are more likely to have a respiratory cause of arrest. We say that, at present, hands-only compressions by lay people is recommended for ADULTS with WITNESSED collapse.
Q: What are your thoughts on delaying airway management for several minutes into the arrest even when EMS personnel are on scene?
A: At present, hands-only (aka continuous compressions) CPR is recommended for untrained lay rescuers. It remains unclear whether hands-only CPR by EMS providers is better than traditional CPR. The Resuscitation Outcomes Consortium is conducting a large randomized trial to test which method is better. Results should be available in 2+ years. You should follow your local medical direction on when to insert an advanced airway until better evidence for or against continuous compressions becomes available.
Q: What's your take on paramedics doing compression-only CPR for the first 2 minutes prior to insertion and ventilation via supraglottic airway device?
Related Question: If an airway is in place (e.g., a King airway) during transport to hospital, should the one rescuer stop to ventilate or only do compressions?
A: At present, hands-only (aka continuous compressions) CPR is recommended for untrained lay rescuers. It remains unclear whether hands-only CPR by EMS providers is better than traditional CPR. The Resuscitation Outcomes Consortium is conducting a large randomized trial to test which method is better. Results should be available in 2+ years. You should follow your local medical direction until better evidence for or against continuous compressions becomes available.
Q: How can more "bystanders" be made aware of the C-A-B protocol, as a change to A-B-C protocol. Thank you for this great & concise presentation. Happy 4th!
A: The public is being educated about changes in guidelines for emergency cardiac care and CPR by using a variety of techniques, including innovative public service announcements. Check out http://www.youtube.com/watch?v=n5hP4DIBCEE.
Q: Is there any value in giving compressions while waiting for the AED to charge after it analyzes?
Related Question: When the defib unit is analyzing a rhythm, do you need to pause while doing CPR?
A: You should try to minimize preshock pauses by continuing compressions while the device charges. Cheskes S, et al. Perishock pause: An independent predictor of survival from out-of-hospital shockable cardiac arrest. Circulation. 2011. http://circ.ahajournals.org/content/early/2011/06/20/CIRCULATIONAHA.110.010736.abstract.
Q: Might you discuss how your respective institutions have had buy-in for post-ROSC cooling programs by the ICU intensivists? Specifically cooling for asystole and PEA as this is a point of contention for us at my hospital.
A: Two trials have demonstrated that post-ROSC induced hypothermia is beneficial in patients resuscitated from ventricular fibrillation. Hypothermia has not been well studied in patients resuscitated from non-shockable rhythms. Absence of evidence does not mean evidence of absence. At my own hospital [Nichol], we induce hypothermia in patients resuscitated from any rhythm.
Q: How can we introduce this information to inner city areas in Ohio to improve CPR survival rates?
A: Each EMS agency has local opportunities for improvement. For many, the first step is starting to audit and feedback process and outcome for patients with out-of-hospital cardiac arrest. Neumar RW. Implementation strategies for improving survival after out-of-hospital cardiac arrest in the United States: Consensus recommendations from the 2009 American Heart Association Cardiac Arrest Survival Summit. Circulation. Jun 21,2011;23(24):2898-2910. Epub May 16, 2011.
Q: My region requires that BLS wait for the arrival of ALS even if transport is delayed, even if CPR is being performed. What's your thought on this?
A: If we understand the question correctly, you are asking whether BLS should transport the patient with ongoing CPR without receiving ALS in the field. Although some EMS agencies may choose to transport patients during ongoing CPR (especially in the presence of persistent VF), transport to an appropriate hospital with a comprehensive post-cardiac arrest treatment system of care is not usually recommended until ROSC has occurred in the field.
Q: Within training scenarios that evaluate CPR administration quality, do you think BLS providers rate higher in quality delivered than ALS providers who often get focused on devices and meds?
A:To the best of our knowledge, there is no evidence that CPR by BLS is better than CPR by ALS providers. But there is evidence that interruptions of compression are harmful, whether as preshock pauses (Cheskes S, et al. Perishock pause: An independent predictor of survival from out-of-hospital shockable cardiac arrest. Circulation. 2011.) or as lower chest compression fractions (Christenson J, et al. Chest compression fraction determines survival in patients with out-of-hospital ventricular fibrillation. Circulation. Sept. 29,2009;120(13):1241-1247. Epub 2009 Sep 14.)
Q: Even though recent studies suggest that epinephrine does not increase survival to discharge, it has shown promise in animal studies. Could this be due to late and infrequent administration, and could epinephrine infusion be helpful if initiated early?
A: Exactly, the timing of epinephrine administration during out-of-hospital cardiac arrest is likely part of the reason for the lack of survival benefit. Although speculative, earlier epinephrine is likely important.