8 Monitoring SpO2
Apply the sensor to the patient. The application site should match the sensor size so that the
sensor can neither fall off, nor apply excessive pressure.
When using the M1195A Infant Finger Sensor, select a finger or toe with a diameter of between 7
and 8 mm (0.27" and 0.31"). When applying a M1193A neonatal sensor do not overtighten the
Check that the light emitter and the photodetector are directly opposite each other. All light from
the emitter must pass through the patient's tissue.
Loose Sensor: If a sensor is too loose, it might compromise the optical alignment or fall off. If it is
too tight, for example because the application site is too large or becomes too large due to edema,
excessive pressure may be applied. This can result in venous congestion distal from the application site,
leading to interstitial edema, hypoxemia and tissue malnutrition. Skin irritations or lacerations may
occur as a result of the sensor being attached to one location for too long. To avoid skin irritations and
lacerations, periodically inspect the sensor application site and change the application site at least every
Venous Pulsation: Do not apply sensor too tightly as this results in venous pulsation which may
severely obstruct circulation and lead to inaccurate measurements.
Ambient Temperature: At elevated ambient temperatures be careful with measurement sites that are
not well perfused, because this can cause severe burns after prolonged application. All listed sensors
operate without risk of exceeding 41°C on the skin if the initial skin temperature does not exceed
Extremities to Avoid: Avoid placing the sensor on extremities with an arterial catheter, an NBP cuff
or an intravascular venous infusion line.
Connecting SpO2 Cables
Connect the sensor cable to the color-coded socket on the measurement device (MMS or module).
You can connect some Philips sensors directly to the measurement device. For other sensors, use the
corresponding adapter cable.
Extension cables: Do not use more than one extension cable (M1941A). Do not use an extension
cable with Philips reusable sensors or adapter cables with part numbers ending in -L (indicates "long"
Electrical Interference: Position the sensor cable and connector away from power cables, to avoid
Humidity: For neonatal patients, make sure that all sensor connectors and adapter cable connectors
are outside the incubator. The humid atmosphere inside can cause inaccurate measurements.