Revised Guidelines for CPR

Earlier guidelines called for only 15 compressions for each two breaths. Another revised guideline was announced for the use of automated electronic defibrillators (AEDs), which now recommends that users lower the number of shocks delivered from three to one.

The changes are based on an analysis by 380 researchers of more than 20,000 animal and human studies, which revealed that more chest compressions led to an increase in coronary and cerebral blood flow. Although the compression ratio has changed, the rate of chest compression remains at 100 per minute. Now that AEDs are located in airports and other busy public places, the survival rate from sudden cardiac arrest has risen from 49% up to 74%. The authors of the study recommend that 911 or other emergency dispatchers be trained to provide CPR instructions by phone. They found that emergency medical care often includes too many ventilations, too many interruptions, with not enough focus on chest compressions.

Post-resuscitation research showed promise in using therapeutic hypothermia to improve neurologic outcome among comatose adult patients who have survived cardiac arrest. Brain cooling has also proven effective for treating newborns with asphyxia at birth.

The researchers presented their findings in an article in the November 28, 2005, online issue of Circulation, a journal of the American Heart Association (Dallas, TX, USA).