Real-time monitoring and feedback improves cardiopulmonary resuscitation
15 November 2005
Dallas, Texas USA. Verbal and visual feedback improves the quality of
cardiopulmonary resuscitation (CPR) delivered by paramedics and emergency
medical technicians, according to the findings of a study announced by Royal
Philips Electronics, in partnership with Laerdal.
Studies presented last week at the American Heart Association's
Scientific Sessions 2005 support the value of Q-CPR, the companies'
proprietary technology that provides real-time CPR monitoring and feedback
for advanced life support (ALS) - trained responders.
Q-CPR, developed by Laerdal and Philips and available only on the
HeartStart MRx monitor/defibrillator, offers medical professionals
corrective feedback on the rate and depth of chest compressions, as well as
the frequency and quality of ventilations (breaths), encouraging them to
adjust their technique, as needed, to improve CPR performance.
Investigators announced the results of the second phase of studies on the
quality of CPR delivered by professional responders in and out of the
hospital. Two papers published in the January 19, 2005 issue of the Journal
of the American Medical Association (JAMA) reported poor adherence to
international guidelines of CPR during both out-of-hospital and in-hospital
cardiac arrest. The studies measured the level of accuracy of CPR delivery
and discovered that, a high percentage of the time, chest compression rates
were too slow, chest compression depth too shallow, and breath rates too
high. The follow-up studies announced at AHA found that incorporating Q-CPR
into their rescue protocol helped professional responders improve the
quality of CPR they deliver.
Dr. Jo Kramer-Johansen of Ulleval University Hospital, Oslo, Norway,
reported on 108 cardiac arrests in three ambulance services in Europe, where
the automatic verbal and visual feedback features of Q-CPR improved the
quality of CPR delivered by the paramedics and emergency medical technicians
(EMTs). With the use of Q-CPR, the median percentage of chest compressions
within CPR guidelines more than doubled from 24% to 53%. Additionally, there
was a significant increase in the mean depth of compressions in those
utilizing Q-CPR (34+/-9 mm to 38+/-6 mm), and a reduction in mean
compression rate (121+/-18 to 109+/-12), which means that the performance
was closer to current AHA guidelines for compression depth of 38 to 51mm and
compression rate of 100 per minute.
"Improving CPR quality is the key factor for improving outcomes after
cardiac arrest in the coming decade," said Professor Petter Steen, the
principal investigator on the study. "While this investigation was not
powered to study outcomes, the results strongly support the need for a
Dr. Ben Abella, from the University of Chicago, presented results showing
that Q-CPR also improved multiple parameters of CPR quality for cardiac
arrest patients treated in-hospital. A related study on how the quality of
CPR affects the success rates of defibrillation, by his colleague Dr. Dana
Edelson, reported that a modest increase in the depth of chest compressions
doubled the chance of defibrillation success, which is associated with more
patients leaving the hospital alive. Dr. Edelson's study garnered her the
Resuscitation Science Symposium's (ReSS) Young Investigator of the Year
Quality CPR and early defibrillation are inextricably linked - the
combination is essential to increase the survival rate for victims of sudden
cardiac arrest (SCA). When breath rates or chest compression targets are not
being met, Q-CPR provides visual and audio cues that encourage rescuers to
adjust their technique. Laerdal, the worldwide leader in CPR solutions,
developed Q-CPR technology with Philips over a five-year period to enable
caregivers to go beyond having a "feel" for doing CPR, by allowing them to
actually see and hear how they are doing, helping to improve the quality of
CPR for their patients in real time.
In addition, Q-CPR enables collection of CPR data for post-event review
and de-brief. This data management feature enables system-wide analysis of
how well CPR is being performed and can help drive improvements in the
quality of CPR in an emergency medical response (EMS) system or hospital.
The Q-CPR device weighs less than a half a pound, adding virtually no weight
to the HeartStart MRx, and is easy to use and apply to the patient.
About CPR and Defibrillation
CPR, or cardiopulmonary resuscitation, is a technique designed to
temporarily circulate oxygenated blood through the body of a person whose
heart has stopped or has an irregular rhythm. It involves determining if the
person is without a pulse, assessing the airway, breathing for the person,
and performing chest compressions to circulate blood to the body's vital
organs. CPR "primes" the heart to receive a defibrillation shock by
perfusing it with blood. It is critical for emergency medical responders to
perform CPR quickly and effectively to maximize the victim's chances of
survival. However, performing and sustaining the appropriate breaths and
chest compressions is difficult, further complicated by such factors as a
chaotic environment or fatigue.
SCA affects 340,000 people each year in the U.S. alone, and fewer than
five percent survive, largely because defibrillators do not get to them in
time or bystander CPR is not always performed. For each minute that passes
before defibrillation therapy reaches a victim, the chance for survival
decreases by about 7 to10 percent. After 10 minutes, few attempts at
resuscitation are successful. Early CPR and defibrillation together with
good post-resuscitation care can improve survival rates substantially.