MAJOR CHANGES AFFECTING ALL RESCUERS

The 5 major changes in the 2005 guidelines are these:
o Emphasis on, and recommendations to improve, delivery of effective chest compressions
o A single compression-to-ventilation ratio for all single rescuers for all victims 
(except newborns)
o Recommendation that each rescue breath be given over 1 second and should produce 
visible chest rise
o A new recommendation that single shocks, followed by immediate CPR, be used to attempt 
defibrillation for VF cardiac arrest. Rhythm checks should be performed every 2 minutes.
o Endorsement of the 2003 ILCOR recommendation for use of AEDs in children 1 to 8 years 
old (and older); use a child dose-reduction system if available.

This section presents an overview of these major changes. The changes are also discussed 
in the sections for lay rescuers and healthcare providers.

Defibrillation

The changes recommended in the 2005 guidelines are designed to minimize interruptions in 
chest compressions. In addition, they acknowledge the high first-shock success of 
biphasic waveforms in eliminating VF or rapid ventricular tachycardia (VT). Major changes 
in defibrillation:

o Immediate defi brillation is appropriate for all rescuers responding to sudden 
witnessed collapse with an AED on site (for victims ?1 year of age). Compression before 
defi brillation may be considered when EMS arrival at the scene of sudden collapse is >4 
to 5 minutes after the call.

o One shock followed by immediate CPR, beginning with chest compressions, is used for 
attempted defi brillation. The rhythm is checked after 5 cycles of CPR or 2 minutes.

o For attempted defibrillation of an adult, the dose using a monophasic manual 
defibrillator is 360 J.

o The ideal defibrillation dose using a biphasic defibrillator is the dose at which the 
device waveform has been shown to be effective in terminating VF. The initial selected 
dose for attempted defibrillation using a biphasic manual defi brillator is 150 J to 200 
J for a biphasic truncated exponential waveform or 120 J for a rectilinear biphasic 
waveform. The second dose should be the same or higher. If the rescuer does not know the 
type of biphasic waveform in use, a default dose of 200 J is acceptable.

o Reaffirmation of 2003 ILCOR statement that AEDs may be used in children 1 to 8 years of 
age (and older). For children 1 to 8 years of age, rescuers should use an AED with a 
pediatric dose-attenuator system if one is available.

o Elements of successful community lay rescuer AED programs were revised.

o Instructions for shocking VT were clarified. What did NOT change:

o The initial dose for attempted defibrillation for infants and children using a 
monophasic or biphasic manual defibrillator. First dose 2 J/kg; second and subsequent 
doses 4 J/kg.

o The dose for synchronized cardioversion for infants and children

o The dose for synchronized cardioversion for supraventricular arrhythmias and for 
stable, monomorphic VT in adults