Pennsylvania Paramedics to Test Promising EMS Techniques

Regional paramedics will soon be testing intravenous fluids, an airway device and altered CPR protocols on some of their most critically ill patients to try to better the odds of surviving trauma and sudden cardiac arrest.

Emergency and trauma researchers from the University of Pittsburgh Medical Center and UPMC Trauma Services, members of the 10-city Resuscitation Outcomes Consortium, will be holding public forums to discuss the studies, which are funded by the National Institutes of Health and other agencies. One will be held in Oakland on Friday.

According to the American Heart Association, 95 percent of people who suffer cardiac arrest will die before they get to a hospital. It kills 900 Americans daily.

If frontline paramedics can't restart a stopped heart, "I never have opportunity to take care of that patient," said UPMC emergency medicine specialist Dr. Clifton Callaway. "This is something where paramedics save lives and nobody else does."

Researchers hope the upcoming studies will show them which rescue procedures will be most effective.

Federal authorities have waived typical informed consent processes because people who will be in the trial could be unconscious or otherwise incapable of agreeing to participate.

Ambulance services in Pittsburgh, Washington, Fayette and Westmoreland counties will be part of the project, as will STAT MedEvac, Dr. Callaway said. Seattle, Milwaukee, San Diego and Toronto are among the cities in the consortium.

One of the studies, led locally by trauma surgeon Dr. Samuel Tisherman, will focus on trauma patients who either have a head injury or are in shock due to blood loss. During initial treatment, paramedics will give them one bag of either standard saline solution; a more concentrated, or hypertonic, saline solution; or the hypertonic solution mixed with a starch called Dextran.

The paramedics will not know which one they will be administering.

Fluids are used to restore blood pressure and circulation, Dr. Tisherman explained. Paramedics currently only give standard saline.

The hypertonic Dextran solution being studied here is already in use in Europe. In cases of head injury, the more concentrated fluids can limit brain swelling and "seem to have beneficial effects on the immune response to trauma," Dr. Tisherman said.

Lab research and small studies in trauma patients hint that giving hypertonic fluids as soon as possible, instead of switching to them after the patient arrives at the hospital, may be of benefit in the long run.

"They look promising," Dr. Callaway said. "They appear to reverse shock more quickly and they seem to eliminate some of those delayed effects of shock that may play out in the hospital."

He is leading the local arm of the second study, which centers on cardiac arrest and has two components.

Cardiac arrest often stems from ventricular fibrillation, in which the heart stops contracting rhythmically and instead quivers chaotically, interrupting blood flow to the body.

If an electrical shock is delivered promptly, the heart could resume pumping normally. That concept has inspired the installation of easy-to-use automated external defibrillators, or AEDs, in public places and other sites.

Paramedics typically don't witness a cardiac arrest, but must drive several minutes to get to the patient, Dr. Callaway pointed out. By then, a fibrillating heart may be less responsive.

"It's used up all its energy stores," he explained. "Defibrillation is less energetic. The most common thing to happen is that rescue shock stops all the electrical activity and the heart is completely silent."

Lab studies suggest that performing for several minutes the chest compressions of cardiopulmonary resuscitation, or CPR, can re-energize the heart and increases the likelihood of restoring a normal beat with a rescue shock, Dr. Callaway said.