Справочник Пользователя для Innokas Yhtyma Oy VC150

KO00065K

VC150 Vital Signs Monitor

8-23

: Masimo rainbow

®

 SET

®

 SpO

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 and special features

rainbow Acoustic Monitoring (RAM) continuously measures a patient’s 
respiration rate based on airflow sounds generated in the upper airway. The 
Acoustic Sensor translates airflow sounds generated in the upper airway to an 
electrical signal that can be processed to produce a respiration rate, measured 
as breaths per minute.

Respiratory sounds include sounds related to respiration such as breath sounds 
(during inspiration and expiration), adventitious sounds, cough sounds, snoring 
sounds, sneezing sounds, and sounds from the respiratory muscles [1].

These respiratory sounds often have different characteristics depending on the 
location of recording [2] and they originate in the large airways where air 
velocity and air turbulence induce vibration in the airway wall. These vibrations 
are transmitted, for example, through the lung tissue, thoracic wall and trachea 
to the surface where they may be heard with the aid of a stethoscope, a 
stethoscope, a microphone or more sophisticated devices.

rainbow Acoustic Monitoring Architecture

The following figure illustrates how a respiratory sound produced by a patient 
can be turned into a numerical measurement that corresponds to a respiratory 
parameter.

Patient

The generation of respiratory sounds is primarily related to turbulent respiratory 
airflow in upper airways. Sound pressure waves within the airway gas and 
airway wall motion contribute to the vibrations that reach the body surface and 
are recorded as respiratory sounds.

Although the spectral shape of respiratory sounds varies widely from person to 
person, it is often reproducible within the same person, likely reflecting the 
strong influence of individual airway anatomy [2-6].

Respiratory airflow 
to sound

Sound to electrical 
signal

Electrical signal to 
digital signal

Digital signal to 
respiratory 
measurement