Within the last several years a new method of
CPR, termed active compression-
decompression (ACD)
CPR was developed. Based upon the theory that active rather than passive chest wall
decompression would augment venous return and ventilation by causing an increase in negative intrathoracic pressure during the
decompression phase of
CPR, a hand-held device was designed and is now being used clinically. Studies in dogs and pigs in
ventricular fibrillation have demonstrated a significant improvement in systolic blood pressure, coronary perfusion pressure and total brain and myocardial blood flow with ACD
CPR compared with standard
CPR. Animal and human studies suggest that the mechanism of ACD
CPR is complex, with coronary perfusion occurring during both the compression and
decompression phases. Clinical studies comparing ACD to standard
CPR in patients in
cardiac arrest demonstrate that immediate
resuscitation rates are nearly doubled when ACD
CPR is started within 10 min after
cardiac arrest. The potential long term benefits of ACD
CPR remain under investigation.