[A device for monitoring respiration during anesthesia: the para-tracheal monitor].

The paratracheal audible respiratory monitor (PTARM) was assessed in anaesthetized patients who were not intubated. Its working principle is simple: the sound generated by the passage of air between the vocal cords is picked up by a microphone placed on the patient's neck; the electronic signal is then amplified and changed into an audible one. It can also be recorded.