During your initial assessment of a patient in cardiac arrest you make the initial determination of the presence, rate and rhythm of breathing. In cardiac arrest, respirations are absent and the proper compression to ventilation ratios are performed. When performing bag-mask or bag-to-tracheostomy ventilations it is important to deliver ventilations with enough volume to make the chest rise.
If possible, provide ventilations using a bag-valve-mask using 100% oxygen. Oxygen should be administered at 10-15 liters per minute; enough to inflate the oxygen reservoir. Similar to what we hear on an airplane; even though the reservoir bag is not fully inflated, oxygen is still flowing.
With an advanced airway in place, including a secured tracheostomy tube CPR should be continuous and ventilations performed at a rate of 1 breath every 6 – 8 seconds.
