Devices and or methods for monitoring respiratory functions of a subject. The system includes a first sensor for measuring the motion of at least on surface of a subject for abdominal, chest, or other area motion to determine volume changes in the area. The second sensor measures the thermal temperature of a target area or device on a surface of the patient, for example near the upper lip of the subject. Specific aspects of the patients breathing health may be analyzed from comparison of respiratory rates calculated from the two sensors. The systems and methods can detect regular breathing, slow breathing (hypopnea), fast breathing (tachypnea), no breathing (apnea), obstructed breathing, or other anomaly. The systems and method may further be configured to trigger an alarm in predetermined situations.