MADISON, Wis. -- Heart attack survival rates have doubled in Madison, Milwaukee and five other places that were among the first to implement new resuscitation guidelines, including the use of a new airflow device, according to a new study.
Nearly 16 percent of heart attack patients in the locations survived after the new measures began in 2005, compared to 8 percent beforehand, the study found. Nationally, the survival rate has been 5 percent.
Of the half-million Americans who have heart attacks each year, an additional 40,000 could survive if every place followed the measures, said Dr. Tom Aufderheide, an emergency medicine professor at the Medical College of Wisconsin in Milwaukee, who conducted the study.
"This is one of the highest survival rates ever seen for patients with cardiac arrest," said Aufderheide, who presented the results this week at the annual meeting of the American Heart Association in Orlando, Fla.
"Our hats are off to hospitals in Madison and the other cities that are adopting what we believe to be the state of the art of care," he said.
The changes involve American Heart Association guidelines announced in 2005 for cardiopulmonary resuscitation, or CPR.
The guidelines instruct emergency medical workers to give 30 chest compressions for every two breaths, instead of the 15 compressions per two breaths generally advised before. Studies found that compressions improve blood flow better than breaths.
About 100 compressions should be given each minute, with the chest fully returned to its normal position each time, the guidelines said.
Furthermore, an "impedance threshold" device should be used to create negative pressure in the chest and thus improve blood flow throughout the body. This is done by blocking air from entering the chest during compression upstrokes.
The only such device on the market, called ResQPOD, is attached to a face mask or breathing tube. A valve allows air in during downstrokes but not during upstrokes.
Aufderheide previously worked on clinical studies of the device, invented by Dr. Keith Lurie of the University of Minnesota and sold by Lurie's Minneapolis-based company, Advanced Circulatory Systems.
For the new study, Aufderheide said, the seven locations selected were "early adopters" of the new CPR guidelines, including the use of the device.
In addition to Madison and Milwaukee, the places are Largo, Fla., Raleigh, N.C., Omaha, Neb., Cypress Creek, Texas and Anoka County, Minn.
Each location reported the outcomes of patients treated in the year before the new measures were implemented and those treated for roughly a year afterward. About 2,300 patients were involved.
After the new approach began, 16 percent of patients who had heart attacks outside of hospitals lived long enough to be discharged after hospitalization, up from 8 percent before, Aufderheide found.
Half of the patients who survived -- before and after the new measures were adopted -- had brain damage from impaired blood flow during their heart attack. That is proof that the new approach wasn't more harmful in that way, Aufderheide said.
Survival figures for just the Madison patients were not available.
But Dr. Marvin Birnbaum, former medical director of the Madison Fire Department, said that among Madison-area patients, the success rate nearly doubled in another important measure; 41 percent of heart attack patients regained pulses en route to the hospital after the new approach started, compared to 22 percent before.
"We saw some people come back that we expected would never come back," Birnbaum said.
Additional steps now being implemented in Dane County could improve survival rates even more, according to Dr. Darren Bean, the current medical director of the Madison Fire Department.
Bean, also a UW Hospital physician, is leading an effort to make three significant changes: using compression-only CPR in many situations, without any breaths; using manual defibrillators instead of automated external defibrillators in some situations; and inducing hypothermia in some patients to reduce brain injury.
NEW CPR APPROACHES: Emergency medical workers in Madison and other cities are implementing new ways of treating cardiac arrest to save more lives.
A device called a ResQPOD attached to a face mask or breathing tube, can improve blood flow by blocking air during chest compression upstrokes.
Madison police are being trained to do compression-only CPR, without breaths. Dispatchers at 911 are telling callers to do the same. The exceptions: if the victims are children or adults who have drowned or been electrocuted.
Madison police and some nearby emergency medical workers are being told to use manual defibrillators instead of automated external defibrillators, or AEDs. AEDs can sometimes delay chest compressions.Paramedics are being trained to induce hypothermia in some patients to reduce brain injury. This involves injecting cold saline into the veins.