The Memphis Fire Department (MFD) and Richmond (Va.) Ambulance Authority (RAA) have a lot in common. Both services are innovators in EMS, have an enthusiastic staff that continues to implement ways to improve the care they render to their patients and both have been searching for ways to improve their resuscitation success rates.
Each also believes they’ve found that way by implementing mechanical CPR in their agency. MFD uses the Physio-Control LUCAS 2 chest compression system and RAA uses the ZOLL AutoPulse non-invasive cardiac support pump.
Though they’re using different devices, their results have been dramatic and have convinced their medical and administrative leadership that mechanical CPR offers many benefits over manual CPR, not the least of which is the ability to maintain consistent and uninterrupted CPR—a key ingredient in the successful resuscitation and discharge of patients neurologically intact from the receiving hospital.
MFD and RAA are both keenly aware that sudden cardiac arrest (SCA) is a leading cause of death among adults over the age of 40 in the United States, that approximately 424,000 people experience EMS-assessed out-of-hospital nontraumatic SCA annually (more than 1,000/day) and nine out of 10 victims currently die.1
The number of people who die each year from SCA is roughly equivalent to the combined number of people who die from Alzheimer’s disease, assault with firearms, breast cancer, cervical cancer, colorectal cancer, diabetes, HIV, house fires, motor vehicle accidents, prostate cancer and suicides combined.
SCA can be best impacted by early intervention with cardiopulmonary resuscitation (CPR), defibrillation, advanced cardiac life support, therapeutic hypothermia and other measures of comprehensive post-resuscitation care.
When bystanders intervene by providing early, high-quality CPR and using automated external defibrillators (AEDs) before EMS arrives, four out of 10 victims survive.1
This article will detail the path each service has taken to success in implementing mechanical CPR on their frontline ambulances.
The MFD Experience
The MFD, the largest EMS system in the state of Tennessee and the Midsouth, responds to more than 121,000 EMS calls annually. MFD is an all advanced life support (ALS) system that operates 36 ALS ambulances, 56 ALS engines, and 21 BLS ladder truck companies with a staff of 500 firefighter/paramedics and 1,100 firefighter/EMTs. The department operates 98 pieces of fire apparatus that are ALS capable. ALS response times average just over four minutes.
In addition to teaching a paramedic education program, MFD is a certified American Heart Association education center, and the only fire department in the U.S. authorized by the Continuing Education Coordinating Board for Emergency Medical Services to issue their own CEUs.
Operating one of the most progressive EMS systems in the U.S. means utilizing some of the latest treatment protocols and procedures. This includes induced hypothermia and mechanical CPR devices for cardiac arrest patients, continuous positive airway pressure for congestive heart failure patients, and intraosseous infusion for intravenous fluid access.
The Assisi Foundation provided the Memphis Fire Department with grant funds to ensure every MFD ambulance was equipped with a LUCAS 2 mechanical CPR device. Photo Roger Cotton
MFD also has an aggressive ST elevation myocardial infarction (STEMI) program with an average time of 65 minutes from first paramedic contact-to-balloon in a hospital cardiac catheterization lab.
The city of Memphis is in the heart of the cardiovascular disease belt, rating high on the incidences of heart disease and strokes, according to the American Heart Association. In addition, a 1994 study published in the Annals of Emergency Medicine found that the level of bystander CPR was significantly lower for African-Americans in Memphis when compared to whites.2 In addition, the traditional social morays prevalent in this region result in a large percentage of patients in cardiac arrest being transported.
Focus on Improving SCA Outcomes
Prior to 2012, the MFD initiated several changes to improve patient outcomes for sudden cardiac arrest. MFD first focused on quality CPR with effective compressions. EZ-IO intraosseous infusion drills and King Airways were added in an effort to reduce the times that compressions were being interrupted. Hypothermia treatment was also initiated in the field. Return of spontaneous circulation (ROSC) rates increased, but MFD continued to look for ways to improve patient outcomes.
In 2011, MFD piloted various mechanical CPR devices, examining cost, crew choice, outcomes and support logistics eventually selecting the Physio-Control LUCAS 2.
Initially, MFD budgetary constraints allowed only 18 devices to be purchased. The devices were deployed randomly throughout the city.
During the first year of deployment, no additional changes were made in protocol or procedure. Detailing of medics resulted in use of the product by a large majority of MFD paramedics.
At the completion of the first year, a comparison between those utilizing the mechanical CPR device and those without revealed a large increase in ROSC rates among patients treated with mechanical CPR.
In determining ROSC rates, MFD included all full arrests where CPR was attempted. While some departments have exclusion criteria for ROSC rates, MFD prefers to include all medical and trauma full arrests in order to more accurately gauge performance, including all heart rhythms.
MFD personnel performed CPR on a total of 1,204 patients in 2012, with ROSC occurring in 250 (21%) of those cases. The LUCAS 2 device was used on 114 full arrests, with ROSC occurring in 37 of those cases. This equaled a ROSC rate of 32% on the LUCAS 2 resuscitations, 11% higher than the overall average for the year.
This substantial improvement in patient care prompted an aggressive effort to fully implement the LUCAS 2 device on all MFD ambulances. To do so, the MFD partnered with the Assisi Foundation of Memphis, a foundation that serves nonprofit organizations working to improve Memphis and the Midsouth.3
Due to the initial success with LUCAS 2 devices, the Assisi Foundation provided grant funds to outfit the remaining MFD ambulances with the mechanical CPR devices.
In 2013, with all 35 ambulances equipped with the LUCAS 2 device, the overall ROSC rate rose to 31%, a 10% increase over the previous year. MFD personnel performed CPR on a total of 1,134 patients in 2013, with ROSC occurring in 348 (30%) of those cases. However, for those receiving mechanical CPR, the ROSC rate was an astounding 49%!
The devices are now widely hailed by MFD paramedics, who feel the impact of the device has been profound. Cardiac arrest care now seems less stressful and more organized. And clearly the results speak for themselves.
What Makes the Difference
The MFD medical direction, training and quality assurance team believes the difference is resuscitation results and ROSC improvement is a result of the consistency of CPR delivery. Despite having plenty of personnel on scene at cardiac arrests, there was always a lack of consistency between the quality of first responders CPR, frequency of compressor rotation and frequent pauses in CPR.
These pauses often occurred for inventions to be performed, but also occurred due to patient movement to locations more conducive to CPR or transportation to the ED.
Despite CPR feedback after the call, improvements were hard to maintain. Training wasn’t frequent enough.
Knowing that the three most important aspects of high-quality CPR are a compression fraction of 90%, a compression rate of 110, and a compression depth of 2 inches, the MFD found that the LUCAS 2 provided the consistency that their system lacked. At the MFD’s 2014 EMS Star of Life reception, nearly every cardiac arrest survivor present had benefited from the LUCAS 2 device. One woman had actually been successfully resuscitated twice in two months with the device.
And the results continue to drive change; EDs in the Memphis area are now adding mechanical CPR. Cardiologists in Memphis are also now performing cardiac catheterization while the LUCAS 2 device helps maintain a pulse.
The RAA Experience
The Richmond Ambulance Authority (RAA) is a high-performance EMS system that’s well-known for technological innovation, operational efficiency and research focusing on CPR, field management of major traumatic injury and safety.
Richmond Fire & EMS provides primary first response and automated external defibrillator care and RAA functions as the sole, all-ALS ambulance provider in the city of Richmond. Fire crews are positioned conventionally in fire stations while RAA’s ALS ambulances are positioned dynamically 24/7 throughout the city using advanced system status management (SSM) that bases the unit placement on data analysis of where the most likely next life-threatening call will occur.
The SSM strategy, refined by more than 24 years of experience, is extraordinarily effective, resulting in an ALS-response time interval to scene consistently greater than 90% in all sectors of the city in 8 minutes, 59 seconds or less.
In 2004, RAA added ZOLL AutoPulse load-distributing band chest compression devices on all of its ALS ambulances. The RAA protocol calls for early application of the device during resuscitation when there’s still maximum patient viability.
RAA has found that the primary advantage of the device is that it provides consistent, high-quality, minimally interrupted chest compressions that can be maintained during defibrillation and, on rare occasions when required, during patient transport. It can be applied quickly by a well-trained crew.
In a before/after implementation of mechanical chest compression comparison, RAA demonstrated a significantly improved survival to hospital discharge.4
However, RAA was cautious to point out that, in its “control period” prior to deploying the mechanical device in 2004, the quality of manual CPR being performed was highly variable. Thus, RAA hypothesized that much of the improvement seen in survival might represent the difference between not-so-well-performed manual CPR (as was the case in most EMS systems and hospitals prior to 2004) vs. consistent, high-quality, mechanical chest compression.
This hypothesis has proven to be well-founded. In a follow-up clinical trial, 522 randomized out-of-hospital cardiac arrest patients in three U.S. and two European sites compared high-quality manual CPR using real-time feedback vs. load-distributing band chest compression with the AutoPulse device.5
Sustained ROSC, 24-hour survival and survival to hospital discharge were statistically equivalent. The 20-minute CPR fraction (the % of time each minute that chest compressions were being performed) in the trial was excellent in both groups (80.4% for AutoPulse and 80.2% for manual CPR).
The RAA conclusion is that mechanical chest compression with devices such as the AutoPulse can at least equal survival outcomes seen with optimally-performed CPR in a clinical trial setting with highly trained crews using real-time quality of CPR feedback devices. However, in the more typical EMS environment, mechanical CPR devices can deliver consistent, high-quality chest compressions over time with minimal interruption in blood flow.
In addition, these devices lessen the physical exhaustion that can occur when manual CPR needs to be sustained for more than a few minutes, and allow rescuers to focus their attention on other important tasks during resuscitation.
1. Newman MM. (n.d.) About SCA. Sudden Cardiac Arrest Foundation. Retrieved March 6, 2014, from www.sca-aware.org/about-sca.
2. Brookoff D, Kellermann AL, Hackman BB, et al. Do blacks get bystander cardiopulmonary resuscitation as often as whites? Ann Emerg Med. 1994;24(6):1147–1150.
3. Assisi Foundation. (n.d.) Our mission is effective philanthropy. Retrieved March 6, 2014, from www.assisifoundation.org.
4. Ong ME, Ornato JP, Edwards DP et al. Use of an automated, load-distributing band chest compression device for out-of-hospital cardiac arrest resuscitation. JAMA. 2006; 295(22):2629–2637.
5. Wik L, Olsen JA, Persse D, et al. Manual vs. integrated automatic load-distributing band CPR with equal survival after out-of-hospital cardiac arrest. The randomized CIRC trial. Resuscitation. 2014; 85(6):741–748.