Welch Allyn 420 Series - Maximum and Minimum Spo 2 Ranges; Pulse Rate

Spot Vital Signs 15
The Spot Vital Signs determines pulse rate as an adjunct to blood pressure measurement and
SpO
2
measurement.
The pulse rate, in beats per minute, is determined primarily from the SpO
2
measurement meth-
odology. In the case where SpO
2
is not available, or is disabled, the pulse rate display is driven
from data collected as part of the blood pressure measurement method.
Removal of the SpO
2
sensor from the patient initiates an audible beep, to alert you to the fact
that the sensor is no longer attached to the patient.
SpO
2
is generally measured via pulses detected using a finger sensor, and performs most accu-
rately with the finger clip sensor. All fingers, except the thumb, can use the finger clip sensor. For
certain situations, measurement and alternate site measurements for SpO
2
can include the ear-
lobe, forehead, and toes. These situations require special sensors (see “Appendix A - SpO2 Sen-
sors” on page 55). The finger clip sensor is recommended for spot checks or short-term
evaluation (less than 60 minutes). Patient supervision is required, since the Spot Vital Signs has
no alarm capability.
Oxygen saturation and pulse rate are displayed on the LCD screen. On each detected pulse, the
pulse signal bar graph flashes. The intensity of this signal is a simple visual indicator of wave-
form signal strength, and can identify possible situations of inadequate pulsatile nature of tissue
for an accurate SpO
2
reading. The update interval bar of the bar graph should correspond to the
patient’s pulse rate. This is an indication of the quality of the SpO
2
signal.
Maximum and Minimum SpO
2
Ranges
The maximum and minimum SpO
2
ranges are as follows:
Pulse Rate
The Welch Allyn Spot Vital Signs determines pulse rate as an adjunct to blood pressure measure-
ment and SpO
2
measurement.
The pulse rate, in beats per minute, is determined primarily from the SpO
2
measurement meth-
odology. In the case where SpO
2
is not available or is disabled, the pulse rate display is derived
by data from the blood pressure measurement method.
Measurement Maximum Minimum
SpO
2
100% 40%