A breathing assistance device is provides guidance to the rescuer, guidance to the victim, and modifies treatment parameters automatically based upon feedback loops relating to patient needs. Guidance can include pictograms showing cartoons of lung expansion, airway patency, breathing rate, and depth of breathing. A microprocessor preferably produces the pictorial guidance as a function of at least one of estimated end tidal CO2, estimated fractional inspired oxygen, estimated fractional expired oxygen, estimated airway resistance, and estimated lung compliance. The microprocessor can also execute a software code that executes a feedback loop that attempts to normalize values of a parameter over time, by controlling at least one pressure in a neck pillow, mask pressure, breathing rate, breathing volume, inspiration time, and expiration time. Contemplated parameters can include estimated end tidal CO2, estimated fractional inspired oxygen, estimated fractional expired oxygen, estimated airway resistance, and estimated lung compliance.