The addition of chest compressions to mask ventilation led to a significant reduction in inflation rate , from 63.9 to 32.9 breaths per minute ( p < 0.0001 ) , mean airway pressure reduced from 7.6 to 4.9 cm H2 O ( p < 0.001 ) , minute ventilation reduced from 770 to 451 mL/kg/min ( p < 0.0001 ) , and there was a significant increase in paired mask leak of 6.8 % ( p < 0.0001 ) .