This slide shows how important the compression rate is and how outcomes directly correlate.
The percentage shown on the bar represents how many victims can be converted from VF to a coordinated rhythm, such as Sinus Rhythm, with defibrillation. A significant drop off is seen below 87 compressions per minute.
With Normal Respirations, the pressure in the chest becomes negative when the diaphragm contracts and pulls down.
The negative pressure in the chest now does 2 things:
1. Draws air into the lungs.
2. Draws venous blood into the inferior and superior vena cava increasing the priming pressure for the heart.
The priming effect is lost with artificial Positive Ventilation. This loss of venous priming changes we deliver CPR.