Abstract: An orally inserted probe and method for measuring vital signs of a mammalian subject is disclosed. Respiratory sensors and a pulse oximetry sensor can measure respiratory rate, heart rate, and oxygen saturation. The sensors are kept in position by a mouthpiece held in the mouth, and by other features of the probe described herein. The mouthpiece can also contain a body temperature sensor. The probe is easy to use, even by an untrained caregiver. A method of measuring frequency of physical changes near a mammalian subject's nose or nostrils can be used to measure respiratory rate. A method of sharing vital signs measurement data with an external device and utilization of the data by medical personnel and caregivers is also disclosed.