A method for treating a patient is provided where a sensed cardiac rhythm is used to adjust electrical stimulation that is used to activate a diaphragm to cause contraction. A cardiac rhythm management device in combination with a diaphragm stimulation device is also provided which includes a cardiac stimulation device configured to provide stimulation to control cardiac rhythm of a subject; and an electrical stimulation device configured to provided electrical stimulation to a subject to activate a diaphragm to increase functional residual capacity of the subject.