OHSU Study Hopes To Determine Best Method Of Reviving Cardiac Arrest Victims

02/23/11  Portland, Ore.

Study will be conducted by EMS professionals at the scene of a person's collapse.

EMS agencies across North America currently use slightly varying methods to try to revive victims of cardiac arrest. OHSU, along with local EMS and health system partners, hopes to conduct a study in the Portland metropolitan area that will determine the best methods of treatment.

The ROC Primed study is the next in a series of federally funded studies known as the Resuscitation Outcomes Consortium (ROC). Portland was designated as a ROC community by the National Institutes Health in 2004. The ROC Primed study will test methods of increasing blood flow to the heart and brain of people who experience cardiac arrest outside of the hospital.

“Outcomes for cardiac arrest patients have not significantly improved in more than 30 years,” said Mohamud Daya, M.D., ROC PRIMED lead study investigator and associate professor of emergency medicine in the OHSU School of Medicine. “The ROC PRIMED study will look at two resuscitation strategies that have shown considerable promise in smaller trials within selected populations to see if they improve the survival rates from cardiac arrest across a wide range of communities in North America.”

Cardiovascular disease is the most common cause of death in the United States and Canada. More than 350,000 people die every year from cardiac arrest in North America. About half of these people have shown no prior symptoms of heart disease, and only about 5 percent will survive.

The first treatment to be used in the ROC PRIMED is an Impedance Threshold Device (ITD). This small, plastic device about the size of a fist fits onto the facemask or breathing tube used during cardiopulmonary resuscitation (CPR). The ITD provides increased blood flow back to the heart during the decompression phase of CPR, allowing more blood to move forward and circulate during the compression phase. People eligible for the study will randomly receive either CPR with the ITD or CPR with a device that looks identical to the ITD, but does nothing. Neither the paramedics nor the investigators will know which one the person receives until after transport to the hospital.

The other treatment in the ROC PRIMED study will look at the use of CPR before shocking the heart of someone experiencing an abnormal heart rhythm that leads to cardiac arrest (ventricular fibrillation). Smaller studies have shown that a sustained amount of CPR before shocking the heart may lead to increased blood flow and improved outcomes, though for many years the standard treatment has involved immediately shocking the heart. Subjects in the ROC PRIMED study will randomly receive either about 30 seconds of CPR or three minutes of CPR before having their heart rhythm checked to determine if a defibrillatory shock is needed.

People eligible for this study will be unconscious as a result of cardiac arrest. Food and Drug Administration (FDA) guidelines allow an investigational treatment to be given in certain life-threatening situations without first getting a person’s permission. The federal regulations that allow this waiver of consent require representatives of the community be consulted and informed of the risks and benefits of the proposed study. ROC investigators will be meeting with neighborhood organizations and community groups to explain the proposed research and answer any questions. The study will also be reviewed and approved by local Institutional Review Boards (IRBs) to ensure the safety of people enrolled in the study.

The ROC PRIMED study will exclude anyone with a known order for refusing life saving treatment, such as a Physicians Orders for Life Sustaining Treatment (POLST) form or other advanced directives, women with an obvious pregnancy and people under arrest at the time of the attack. The study will only enroll people ages 18 and older, though the expected median age of enrollees is 63. ROC investigators hope to enroll about 600 people annually in the ROC PRIMED study while the ROC consortium as a whole aims to enroll about 15,000 people. Knowledge gained from this study should help guide treatment for future cardiac arrest victims in the Portland community and others throughout North America.

ROC is funded by the National Institutes of Health. This group of 11 regional medical centers across the United States and Canada seeks to find promising scientific and clinical advances to improve survival from cardiac arrest and severe trauma. The ROC will consist of multiple studies during the course of several years, testing new or alternative drugs, tools and techniques. Investigators with local EMS agencies and hospitals in Multnomah, Clackamas, Washington and Clark counties will together to conduct this important research.

“We couldn’t conduct this research without the cooperation of the EMS community and local health systems,” said Jerris Hedges, M.D., Oregon ROC principal investigator, professor of emergency medicine and vice dean of the OHSU School of Medicine. “For the EMS community and the investigators, this is about improving the public’s health by determining the best way to treat cardiac arrest victims. Only by testing these promising treatments outside the hospital will we be able to decide what works best for the citizens in the greater Portland area.”

People who would like a presentation to a community group, and people wishing to exclude themselves from the study should call Denise Griffiths at 503 494-7015.