What is cardiac arrest?
Cardiac arrest is a serious medical condition. During a cardiac arrest the heart stops beating effectively and is unable to pump blood to the organs of the body. It usually occurs suddenly and unexpectedly. Death can occur within minutes unless treatment is started.
What is an out-of-hospital cardiac arrest?
Cardiac arrest can happen any place. If the cardiac arrest occurs outside of the hospital, it is referred to as an out-of-hospital cardiac arrest.
What is the incidence of out-of-hospital cardiac arrest?
Cardiac arrest is one of the most common killers of Americans each year. It is estimated that 300,000 persons have a cardiac arrest each year in the United States, the vast majority of whom die before ever reaching the hospital.
What causes a cardiac arrest?
The most common underlying reason for patients to die suddenly from cardiac arrest is coronary heart disease. These people are at varying risks for cardiac arrest. In general, those with damaged hearts are at greater risk. Specific risk factors include a previous episode of cardiac arrest, a history of heart failure and a family history of sudden cardiac arrest. Other factors besides heart disease can cause cardiac arrest. They include respiratory arrest, electrocution, drowning, choking and drug overdoses. Cardiac arrest can also occur without any identifiable cause.
What is the treatment for out-of-hospital cardiac arrest?
The first step in the treatment of an out-of-hospital cardiac arrest is quick identification of the problem. This can be done by checking for signs of life (consciousness, movement, normal breathing). Once a cardiac arrest is confirmed, quick access to the 911 system is essential. The standard treatment for cardiac arrest is immediate CPR, which can be started by citizens before emergency medical services providers are on the scene. Once the emergency medical providers are on scene they continue CPR. Many times an electrical shock or shocks are given to the heart to try and restore a normal heartbeat. This electrical shock is called defibrillation. Other procedures to treat patients in cardiac arrest are the placement of electrodes to monitor the heart’s electrical rhythm, the placement of an intravenous line (needle into the vein or other portion of the circulation) to give fluids and medications, and the placement of an endotracheal tube (a tube placed into the throat through the mouth) to support breathing.
How does CPR help?
During a cardiac arrest the heart no longer pumps blood and the organs of the body no longer receive oxygen and so begin to die. CPR consists of pumping on the patient’s chest and delivering breaths to produce some circulation until the heart can be restarted. When the chest is compressed, oxygen-rich blood is pumped forward. When the chest is released, oxygen-poor blood is brought back to the heart where it can be restored with oxygen before being pushed out to the body with another compression. Both actions – pushing oxygen-rich blood forward and bringing oxygen-poor blood back to the heart - are important. CPR produces some blood flow – but only about 30% of normal circulation. Methods to improve the circulation produced by CPR may lead to better survival.
How continuous chest compression affect blood flow?
Each time the chest is compressed, blood is circulated in the body. Each time a breath is given, the blood in the lungs is enriched with oxygen, which is then circulated to the body. It is not known if circulation and oxygen delivery to the body is improved by not interrupting chest compressions when a breath is given, or if the brief time chest compressions are interrupted for breathing is compensated for by better breathing and oxygen delivery to the body. These two methods of CPR will be compared in this study to determine whether survival is better improved by one or the other forms of CPR.
What is the effect of heart rhythm medications on the heart?
Evidence indicates that an electrical shock applied early after cardiac arrest helps restart the heart so that common practice is to administer a shock for dangerous heart rhythms. When a shock is given to the heart during cardiac arrest, it resets the abnormal heart rhythm. However, this does not always work, nor necessarily keep a dangerous rhythm from coming back. Heart rhythm medications such as lidocaine or amiodarone are often used in such circumstances to help restore or maintain a normal heart beat. However, no study has yet shown that the use of these medications improves survival after cardiac arrest. It is possible that commonly used rhythm medicines like amiodarone and lidocaine are not actually helpful for treating cardiac arrest, might have side effects that could cancel out any good they might do, or could even make outcome from cardiac arrest worse. This can’t be known unless the drugs are compared against one another, as well as compared against giving neither one. This study will compare these medications, treating some patients with standard treatments for cardiac arrest, in addition to which some patients will receive lidocaine, some amiodarone, and some will receive neither of these rhythm medications (or what is called placebo (a harmless water solution)).
Who will be eligible to be enrolled in the study?
Many adult subjects treated by King County EMS for a cardiac arrest during the study period will be eligible for these studies. The cardiac arrest cannot be due to trauma such as a gunshot wound, stabbing, or severe motor vehicle accident. And persons with an advance directive (“do not resuscitate”) will not be treated in the trial, in respect of their wishes. Similarly, patients who are known to be pregnant, children, and those who are known to have indicated in advance that they do not wish to be enrolled in a research trial (wearing an “opt out” bracelet) will not be enrolled.
How will the study decide which treatment is provided?
Each type of CPR (chest compressions that are interrupted or not interrupted for breaths) is the accepted standard of care in adults with cardiac arrest, depending upon the community in which cardiac arrest occurs. It is not known if one type of CPR is better than the other for treating cardiac arrest. During the study period, all adults with cardiac arrest in King County will receive one or the other type of CPR described as part of standard care. That is, in some communities within King County one type of CPR will be being performed during some months of the year, and the other type during other months of the year. Thus the choice of which type of CPR someone in cardiac arrest might receive will be by chance, depending upon where and when the cardiac arrest occurs. In this study, one or the other type of will be performed during only the first few minutes of CPR, or until a breathing tube is placed in the throat through the mouth. After a breathing tube is placed, only the kind of standard CPR that is customarily done in patients with a breathing tube will be performed.
For the drug study (ALPS), if the heart rhythm is also resistant to an electrical shock a person enrolled in this study may receive one of two heart rhythm medications (lidocaine or amiodarone), or neither (that is a placebo). The choice of these treatments will be decided by chance (similar to the toss of a coin.) All other standard treatments will be given. We believe that this type of study, called a randomized trial, will enable the truest determination of the best approach for the treatment of cardiac arrest.
There is a chance of receiving one or both of the treatments described here (that is, the CPR study treatment, and the drug study treatment).
What are the alternatives to taking part in the studies?
Anyone wishing to “opt out” in advance of possibly being enrolled in either of these studies will have an opportunity to do so (see section
Can I “opt out” in advance of potentially being treated in the study? below).
For both trials, the best known treatments will be provided during the cardiac arrest. The alternative to taking part in the CPR study will be to have received the same standard CPR treatment, but not have any research information gathered about the response to it. The alternative to taking part in the drug study (ALPS) is to have possibly received one of the identical medicines (lidocaine), but for this not to have been decided by chance, nor to have any research information gathered about the response to it.
For those who receive either or both of these emergency study treatments, but do not wish to have any further involvement with the studies, they will also have the opportunity to withdraw from further participation when notified about their treatment.
Who is supporting the study?
The study is supported by the National Institutes of Health, a branch of the U. S. Federal government.
Are other communities participating?
Yes, a total of 10 communities from the US and Canada are participating. More information about the collaboration of communities to help learn more about treatment of cardiac arrest is available at (CTC Website).
How long will the study take?
Once underway, the studies will take about 3 years to complete.
Who are the investigators for the study?
Investigators from the University of Washington and Harborview Medical Center in collaboration with the Emergency Medical Services agencies of King County will conduct the study.
What about consent for the study?
The studies are being done under “exception from consent”. This means subjects are enrolled in the study without their prior consent. Federal regulations usually do not allow patients to be enrolled in a study without their informed consent or without the consent of their next of kin. However, in certain limited situations, such as emergency medicine research, the U. S. Food and Drug Administration (FDA) does allow some studies to be conducted without prior consent. In order to be able to do a study using “waiver of consent” all of the following requirements established by the FDA must be met.
-
A life-threatening situation with unproven or unsatisfactory treatment where research is necessary to improve outcome.
-
Obtaining informed consent is not feasible because the patient is unresponsive and treatment must begin immediately.
-
Participation in research has the prospect of direct benefit because the situation necessitates an intervention, science supports the potential of direct benefit and the risks of the research are reasonable compared to the medical condition.
-
The research could not practicably be done without waiver of informed consent.
-
The potential therapeutic window is short (in the case of cardiac arrest, treatment needs to be given within minutes)
-
The researchers must notify persons who were treated in the trial, providing them with information about it, and giving them opportunity to withdraw from further participation, if desired. There is no further participation involved in this trial, apart from the review of medical records to determine the effects of treatment.
-
An Institutional Review Board (IRB) must approve the study.
-
A Data Safety Monitoring Board must regularly evaluate the study for safety.
-
Subjects or their legally authorized representative will be contacted as soon as possible after enrollment into the study. The purpose of this contact will be to provide information about the study and provide an opportunity to withdraw from further participation, if desired. That is, anyone not wishing to have any further involvement with the study will have the opportunity to withdraw from further participation when notified about their treatment.
Can I “opt out” in advance of potentially being treated in the study?
Yes. Anyone not wishing to be enrolled in the trial will be provided opportunity to “opt out” in advance of treatment by contacting us at the address, phone, or email shown below. Those contacting us will be mailed a bracelet without cost which, when worn indicates being ineligible for the study. This bracelet must be worn or displayed in a recognizable manner in order to be identified by prehospital providers. Prehospital providers will be trained to recognize such bracelets and that its presence excludes the patient from enrollment in the trial. Every effort will be made to comply with the patient’s wishes. However, in some circumstances, emergency treatment may begin before the presence of the bracelet is recognized. Should this happen, we will inform the patient and family of this occurrence. In previous trials of cardiac arrest performed in Seattle/King County, no patient wearing an “opt out” bracelet ever received research treatment.
How will I know if my relative or I was enrolled in the study?
You or your legally authorized representative will be notified soon after enrollment into the study.
Community consultation is required before any study can be done using a waiver of consent. The purpose of this consultation is to make sure the community agrees to participate in the study and that any concerns about that participation are addressed. Researchers are required to disclose to the public the nature, risks, and benefits of the study. This is being done through a variety of means:
- This website
- Press releases
- Local advertising
- Community telephone survey (using random digit dialing)
How will enrolled subjects’ medical information be kept confidential?
By law, researchers must protect the privacy of health information about subjects. We make every effort to keep the information confidential. All subjects enrolled in the trial will be assigned a code number. This code number is used on any data we collect. A key linking the subject to the code number is kept locked in a secure location and will be available only to the investigators. After this study is completed this key will be destroyed
Who oversees this study?
This study is being conducted by the investigators listed below, who are directly responsible for its conduct. In addition, this study has been reviewed and approved by the University of Washington Institutional Review Board (IRB), and the heart rhythm medication study by the U. S. Food and Drug Administration (FDA). As an added safety measure, an independent Data Safety and Monitoring Board (DSMB) receives regular reports on the trial, and periodically reviews and evaluates outcomes with the various treatments that are under study. The DSMB has the authority to alter or stop the trial should it identify any concerns that it feels requires doing so.
Who are the investigators for the study?
Principal Investigator:
Peter J. Kudenchuk, MD
Professor of Medicine
Division of Cardiology
University of Washington
Co-investigators:
Tom Rea, MD
Professor of Medicine
Division of General Medicine
Harborview Medical Center
Medical Director: King County Medic One
Public Health – Seattle & King County
Mickey Eisenberg, MD
Professor of Medicine
Division of Emergency Medicine
University of Washington
Medical Director: King County Emergency Medical Services
Public Health – Seattle & King County
Nurse Coordinators:
Karen Dong, RN (ALPS)
Michele Olsufka, RN (ALPS)
Sally Ragsdale, RN (CPR Study and ALPS)
Debi Solberg, RN (CPR Study and ALPS)
On-line Survey:
Click here to let us know your opinions!
How can I get more information about the study?
We anticipate that these studies will contribute to a better understanding of how we can improve the treatment of patients that experience cardiac arrest. We hope that this study will improve outcomes from this very serious condition.
We are very interested in your comments.
Please call Sally Ragsdale RN or Debi Solberg RN, Research Coordinators, with any questions or comments regarding the CPR study.
Phone: 206.447.5671
Email:
skcroc@u.washington.edu
(PLEASE NOTE THAT WE CANNOT GUARANTEE THE CONFIDENTIALITY OF EMAIL CORRESPONDENCE)
Address: Resuscitation Outcomes Consortium (ROC)
Logan Building,
500 Union Street, Suite #805
Seattle, WA 98101
www.uwheartroc.org
Additional Information and Publications:
www.uwctc.org