Microsoft Word - Table of Contents

Equipment*Package:*Pulse&Oximeter*UDMS*#:&17148&Date*of*Creation:&October&18,&2015&Creator:&Complied&by&Cassandra&Stanco&for*Engineering&World&Health&(EWH)***Equipment*Packet*Contents:*This&packet&contains&information&about&the&operation,&maintenance,&and&repair&of&pulse&oximeters.&&Part*I:*External*From*the*Packet:** 1. An*Introduction*to*Pulse*Oximeters:*&PowerPoint&*Part*II:*Included*in*this*Packet:** 1. Operation*and*Use:*a. Brief&Introduction&to&Pulse&Oximeters&(p.&3)&b. Introduction&to&Pulse&Oximeters&(p.&4N7)&c. Operation&and&Use&of&Pulse&Oximeters&(p.&8N13)&2. Diagrams*and*Schematics:*a. Figure&1:&Example:&Flowchart&for&Addressing&Hypoxia&(p.&15)&b. Figure&2:&WHO&Specification&for&Line&Powered&Pulse&Oximeter&(p.&16)*c. Figure&3:&WHO&Specification&for&Battery&Powered&Pulse&Oximeter&(p.&17)*3. Preventative*Maintenance*and*Safety:*a. Pulse&Oximeter&Preventative&Maintenance&(p.&19)*b. Pulse&Oximeter&Safety&(p&.20N22)*4. Troubleshooting*and*Repair:**a. Pulse&Oximeter&Troubleshooting&Flowchart&(p.&24N27)*b. Pulse&Oximeter&Troubleshooting&Table&(p.&28N29)*5. Resources*for*More*Information*a. Resources&for&More&Information&(p.&31)*b. Bibliography&(p.&32)** &** **




*1.*Operation*and*Use*of*Pulse*Oximeters*****Featured*in*this*Section:****Strengthening&Specialised&Clinical&Services&in&the&Pacific.&User(Care(of(Medical(Equipment:(A(first(line(maintenance(guide(for(end(users.&(2015).& *&Wikipedia.&“Pulse&Oximeter.”&Wikipedia,&p.&1N4.&Retrieved&from:&https://en.wikipedia.org/wiki/Pulse_oximetry&** *&* ** *




User Care of Medical Equipment – First line maintenance for end users


48


Chapter 4.14 Pulse Oximeters


Function
A pulse oximeter is a device that non-invasively monitors the oxygen saturation of a patient's blood. It


measures the amount of oxygen in a patient‟s arterial blood during operations and diagnosis. This level of
oxygen, or „oxygen saturation‟ is often referred to SpO2, measured in %, and this is displayed on the pulse
oximeter. A pulse oximeter also displays pulse rate.




How it works
The coloured substance in blood, haemoglobin, is carrier of oxygen and the absorption of light by


haemoglobin varies with the amount of oxygenation. Two different kinds of light (one visible, one invisible) are
directed through the skin from one side of a probe, and the amount transmitted is measured on the other side.
The machine converts the ratio of transmission of the two kinds of light into a % oxygenation. Pulse oximeter
probes can be mounted on the finger or ear lobe.















Pulse oximeter 1


Pulse oximeter


Typical measurement through the fingernail


A fingertip pulse oximeter with waveform


A handheld pulse oximeter


A pulse oximeter is a medical device that indirectly measures the
oxygen saturation of a patient's blood (as opposed to measuring oxygen
saturation directly through a blood sample) and changes in blood
volume in the skin, producing a photoplethysmograph. It is often
attached to a medical monitor so staff can see a patient's oxygenation at
all times. Most monitors also display the heart rate. Portable,
battery-operated pulse oximeters are also available for home
blood-oxygen monitoring. The original oximeter was made by Milliken
in the 1940s.[1] The precursor to today's modern pulse oximeter was
developed in 1972, by Aoyagi at Nihon Kohden using the ratio of red
to infrared light absorption of pulsating components at the measuring
site. It was commercialized by Biox in 1981. The device did not see
wide adoption in the United States until the late 1980s.


Function
A blood-oxygen monitor displays the percentage of arterial
hemoglobin in the oxyhemoglobin configuration. Acceptable normal
ranges are from 95 to 100 percent, although values down to 90% are
common. For a patient breathing room air, at not far above sea level,
an estimate of arterial pO2 can be made from the blood-oxygen monitor
SpO2 reading.


A pulse oximeter is a particularly convenient noninvasive
measurement instrument. Typically it has a pair of small light-emitting
diodes (LEDs) facing a photodiode through a translucent part of the
patient's body, usually a fingertip or an earlobe. One LED is red, with
wavelength of 660 nm, and the other is infrared, 905, 910, or 940 nm.
Absorption at these wavelengths differs significantly between
oxyhemoglobin and its deoxygenated form; therefore, the
oxy/deoxyhemoglobin ratio can be calculated from the ratio of the
absorption of the red and infrared light. The absorbance of
oxyhemoglobin and deoxyhemoglobin is the same (isosbestic point)
for the wavelengths of 590 and 805 nm; earlier oximeters used these
wavelengths for correction for hemoglobin concentration.[2]


The monitored signal bounces in time with the heart beat because the
arterial blood vessels expand and contract with each heartbeat. By
examining only the varying part of the absorption spectrum
(essentially, subtracting minimum absorption from peak absorption), a
monitor can ignore other tissues or nail polish, (though black nail
polish tends to distort readings)[3] and discern only the absorption
caused by arterial blood. Thus, detecting a pulse is essential to the operation of a pulse oximeter and it will not
function if there is none.




Pulse oximeter 2


Advantages
A pulse oximeter is useful in any setting where a patient's oxygenation is unstable, including intensive care,
operating, recovery, emergency and hospital ward settings, pilots in unpressurized aircraft, for assessment of any
patient's oxygenation, and determining the effectiveness of or need for supplemental oxygen. Assessing a patient's
need for oxygen is the most essential element to life; no human life thrives in the absence of oxygen (cellular or
gross). Although a pulse oximeter is used to monitor oxygenation, it cannot determine the metabolism of oxygen, or
the amount of oxygen being used by a patient. For this purpose, it is necessary to also measure carbon dioxide (CO2)
levels. It is possible that it can also be used to detect abnormalities in ventilation. However, the use of a pulse
oximeter to detect hypoventilation is impaired with the use of supplemental oxygen, as it is only when patients
breathe room air that abnormalities in respiratory function can be detected reliably with its use. Therefore, the
routine administration of supplemental oxygen may be unwarranted if the patient is able to maintain adequate
oxygenation in room air, since it can result in hypoventilation going undetected.


Because of their simplicity and speed, pulse oximeters are of critical importance in emergency medicine and are also
very useful for patients with respiratory or cardiac problems, especially COPD, or for diagnosis of some sleep
disorders such as apnea and hypopnea. Portable, battery operated pulse oximeters are useful for pilots operating in a
non-pressurized aircraft above 10,000 feet (12,500 feet in the US)[4] where supplemental oxygen is required. Prior to
the oximeter's invention, many complicated blood tests needed to be performed. Portable pulse oximeters are also
useful for mountain climbers and athletes whose oxygen levels may decrease at high altitudes or with exercise.
Those using portable pulse oximeters are also making use of blood oxygen charting software. These charting
methods provide print outs for the patients physician of blood oxygen and pulse, and reminders to check blood
oxygen levels.


Limitations and Advancements
Oximetry is not a complete measure of respiratory sufficiency. A patient suffering from hypoventilation (poor gas
exchange in the lungs) given 100% oxygen can have excellent blood oxygen levels while still suffering from
respiratory acidosis due to excessive carbon dioxide.


It is also not a complete measure of circulatory sufficiency. If there is insufficient bloodflow or insufficient
hemoglobin in the blood (anemia), tissues can suffer hypoxia despite high oxygen saturation in the blood that does
arrive.


A higher level of methemoglobin will tend to cause a pulse oximeter to read closer to 85% regardless of the true
level of oxygen saturation. It also should be noted that the inability of two-wavelength saturation level measurement
devices to distinguish carboxyhemoglobin due to carbon monoxide poisoning from oxyhemoglobin must be taken
into account when diagnosing a patient in emergency rescue, e.g., from a fire in an apartment. A Pulse CO-oximeter
measures absorption at additional wavelengths to distinguish CO from O2 and determines the blood oxygen
saturation more reliably.


Appropriate fluid levels are vital to reducing postoperative risks and improving patient outcomes as fluid volumes
that are too low (under hydration) or too high (over hydration) have been shown to decrease wound healing, increase
risk of infection and cardiac complications.[5]




Pulse oximeter 3


Increasing usage
According to a report by Frost & Sullivan entitled U.S. Pulse Oximetry Monitoring Equipment Market, US sales of
oximeters were worth $201 million in 2006. The report estimated that oximeter sales in the US would increase to
$310 million annually by 2013.[6]


In 2008, more than half of the major internationally-exporting medical equipment manufacturers in China were
producers of pulse oximeters.[7]


In June, 2009, video game company Nintendo announced an upcoming peripheral for the Wii console, dubbed the
"Vitality Sensor," which consists of a pulse oximeter. This marks the onset of the use of this device for non-medical,
entertainment purposes.[8] [9]


See also
• Arterial blood gas
• Medical equipment
• Pulse oximetry
• Capnography, measuring of carbon dioxide (CO2) in the respiratory gases
• Integrated Pulmonary Index


External links
• Principles of Pulse Oximetry Technology [10]


• How Pulse Oximetry Works [11]


References
[1] G.A. Millikan, The oximeter: an instrument for measuring continuously oxygen-saturation of arterial blood in man, Rev. Sci. Instrum. 13


(1942) 434– 444.
[2] Pulse Oximetry (a review) (http:/ / www. frca. co. uk/ SearchRender. aspx?DocId=1133& Index=D:\dtSearch\UserData\AUK&


HitCount=11& hits=3+ 10+ a7+ a8+ c8+ 10b+ 10c+ 17a+ 191+ 1ac+ 1b8+ ) Anaesthesia UK 11 Sept 2004.
[3] Brand TM, Brand ME, Jay GD. Enamel nail polish does not interfere with pulse oximetry among normoxic volunteers (http:/ / www. ncbi.


nlm. nih. gov/ entrez/ query. fcgi?cmd=Retrieve& db=pubmed& list_uids=12212998) J Clin Monit Comput. 2002 Feb;17(2):93-6.
[4] Code of Federal Regulations (http:/ / www. airweb. faa. gov/ Regulatory_and_Guidance_Library/ rgFAR. nsf/ 0/


BA9AFBF96DBC56F0852566CF006798F9?OpenDocument& Highlight=oxygen) Federal Aviation Administration
[5] Ishii M, Ohno K. Comparisons of body fluid volumes, plasma renin activity, hemodynamics and pressor responsiveness between juvenile and


aged patients with essential hypertension. (http:/ / www. unboundmedicine. com/ medline/ ebm/ record/ 870721/ full_citation/
Comparisons of body_fluid_volumes_plasma_renin_activity_hemodynamics_and_pressor_responsiveness_between_juvenile_and_aged_patients_with_essential_hypertension_)
Jpn Circ J 1977 Mar; 41(3):237-46.


[6] "Pulse Oximetry Market to Grow 150 Percent by 2013" (http:/ / homecaremag. com/ news/ pulse-oximetry-market/ index. html),
HomeCareMag.com (http:/ / homecaremag. com/ ) (Paramus, New Jersey: Penton Media Inc.), 2007-08-20, , retrieved 2009-01-19


[7] "Key Portable Medical Device Vendors Worldwide", China Portable Medical Devices Report (Beijing: ResearchInChina), December 2008
[8] Pigna, Kris (2009-06-02). "Satoru Iwata Announces Wii Vitality Sensor" (http:/ / www. 1up. com/ do/ newsStory?cId=3174528). 1UP.com. .


Retrieved 2009-06-02.
[9] "Nintendo Introduces New Social Entertainment Experiences at E3 Expo" (http:/ / e3. nintendo. com/ pressrelease/ ). Nintendo of America.


2009-06-02. . Retrieved 2009-06-02.
[10] http:/ / www. oximetry. org/ pulseox/ principles. htm
[11] http:/ / www. nda. ox. ac. uk/ wfsa/ html/ u05/ u05_003. htm




Article Sources and Contributors 4


Article Sources and Contributors
Pulse oximeter  Source: http://en.wikipedia.org/w/index.php?oldid=355619115  Contributors: Academic Challenger, Aiko, Alex.tan, Almazi, Alvinsagar, Animeronin, Arniebuteft,
Bambalabamba, Beelaj., Bgranat, Bryan Derksen, Bunnyhop11, Cburnett, CharlesHBennett, Colenso, DMacks, Damzow, Dkellner, Doctortomwiki, Dr.michael.benjamin, Draeco, DragonSlaveII,
Dreamyshade, Elonka, Evil saltine, Fluidcreativity, Folajimi, FourteenDays, GraemeL, Gurch, HJames, Hichris, Hu12, Islander, Jerrynovak, Jfdwolff, Joe Brigen, JoeBrigen, Karada, Karensams,
Katoa, Kauczuk, Kdtop, Kyoko, MER-C, Mani1, Medicaltechwriter, Mr Bungle, MrDolomite, Nono64, Not R, Notepadpage, PurpleHz, Rama, Rdarwin, Rjwilmsi, Rlcantwell, Ronk01, Rrburke,
SarekOfVulcan, Scientificone, Shaddack, Shushing3, Sortior, Spellman999, Spl4, Srice13, Struthious Bandersnatch, TaintedMustard, Thinkpaul, WacoJacko, Weregerbil, WhatamIdoing, Wiki
Jibiki, Wmghori, Wormholio, 97 anonymous edits


Image Sources, Licenses and Contributors
Image:FingertipPulseOximeter-MD300C1NoLogo.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:FingertipPulseOximeter-MD300C1NoLogo.jpg  License: GNU Free
Documentation License  Contributors: User:SarekOfVulcan, User:Thinkpaul
Image:PulseOximeterMD300C63.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:PulseOximeterMD300C63.jpg  License: Creative Commons Attribution-Sharealike 3.0
 Contributors: User:Thinkpaul
Image:HandheldPulseOximeter-MD300I.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:HandheldPulseOximeter-MD300I.jpg  License: Creative Commons Attribution-Sharealike
3.0  Contributors: User:Thinkpaul


License
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http:/ / creativecommons. org/ licenses/ by-sa/ 3. 0/




Pulse Oximeters 




Pulse Oximeters

General Description

The Ohmeda Biox 3700 Pulse Oximeter, for example, is a stand alone, noninvasive,
arterial oxygen saturation monitor. Ear, finger, and flex probes connect the monitor to the
patient, and provide continuous oxygen saturation (SaO2) and pulse rate readings.

The oximeter determines a patient’s arterial oxygen saturation and pulse rate by
measuring the absorption of selected wavelengths of light. The light generated in the
probe passes through the tissue and is converted into an electronic signal by the
photodetector. The electronic signal passes to the oximeter and photodetector. Analog
and digital signal processing converts the light intensity information into SaO2 and pulse
rate values. Two liquid crystal displays (LCD) present patient data and status
information. The digital LCD displays SaO2 and pulse rate, while the graphic LCD
displays the plethysmographic waveform, the Signal Strength Indicator, Trend Data,
Status Messages and Alarm Messages.

Theory

This chapter covers the theory of operation for

x The monitor’s oximetry function
x The circuit boards associated with the oximetry function: The MINX board and the


MINX interface board
x The front panel interconnect board, the printer terminator board, and the power


supply board
x The monitor’s printing function.
x The circuit boards associated with the printing function: the printer connector board


and the printer board.

The pulse oximeter determines a patient’s arterial oxygen saturation and pulse rate. It
measures the absorption of selected light wavelengths that are generated in a probe. The
light passes through the tissue and is converted into an electronic signal by a
photodetector (some light is absorbed by the tissue.) The electronic signal passes to the
Signal processing section of the MINX board where it is amplified and processed. The
light intensity information is converted into SaO2 and pulse rate values.

NOTE: The SaO2 read by oximeters and displayed on this monitor, is now referred to as
SpO2. This additional definition is now required because a two-wavelength instrument
cannot measure the presence of dyshemoglobins or other pigments. The presence of
appreciable amounts of these substances may result in erroneous readings.




81


Developing World Healthcare Technology Laboratory. “Pulse Oximeters.” From the Publication:


“Biomedical Technicians Training Program, Session 3 v2, Special Topics: Cardiac Equipment.”


Engineering World Health, March 1, 2011, p. 1-161.




Pulse Oximeters 




The functioning of the oximeter is based on the assumption that hemoglobin exists in two
principle forms in the blood:


x Oxygenated (with O2 molecules loosely bound) or HbO2.

x Reduced (with no O2 molecules bound) or Hb.



Arterial oxygen saturation (SaO2) is defined as the ratio of oxygenated hemoglobin
(HbO2) to total hemoglobin [HbO2 + Hb]:



HbHbO


HbO
SaO 2


2
2 *



(*Interfering substances: Carboxyhemoglobin may erroneously increase readings. The
level of increase is approximately equal to the amount of carboxyhemoglobin present.
Dyes, or any substances that contain dyes, that change usual arterial pigmentation may
cause erroneous readings.)

An oximeter measures the relative absorption of selected wavelengths of light passing
through a living tissue sample. Since oxygenated hemoglobin and reduced hemoglobin
absorb light as known functions of wavelengths, the relative percentage of these two
constituents, and SaO2 are calculated. The central problem in translating oximetry theory
into a medical device is differentiating between the absorption due to oxygenated and
reduced hemoglobin and the absorption due to all other tissue constituents.

The Ohmeda Biox 3700, for example, solves this problem with a patented two
wavelength, pulsatile system. The pulsation of arterial blood flow present at a particular
test site modulates the light the oximeter’s probe detects. Since other fluids and tissues
present at the test site generally do not pulsate, they do not modulate the light passing
through the test site area. Therefore, the attenuation of light energy due to arterial blood
flow can be detected, and isolated, thus providing the basis for the necessary calculations,
by using the pulsatile portion of the incoming signal.

Two wavelengths of light, red and infrared, are utilized to gauge the presence of
oxygenated and reduced hemoglobin.












82


Developing World Healthcare Technology Laboratory. “Pulse Oximeters.” From the Publication:


“Biomedical Technicians Training Program, Session 3 v2, Special Topics: Cardiac Equipment.”


Engineering World Health, March 1, 2011, p. 1-161.




Pulse Oximeters 



























EXTINCTION versus WAVELENGTH GRAPH

Oxygenated hemoglobin (HbO2) and reduced hemoglobin (Hb) exhibit markedly
different absorption (extinction) characteristics to red light @ 660 nm and infrared light
@ 940 nm.



















83


Developing World Healthcare Technology Laboratory. “Pulse Oximeters.” From the Publication:


“Biomedical Technicians Training Program, Session 3 v2, Special Topics: Cardiac Equipment.”


Engineering World Health, March 1, 2011, p. 1-161.




Pulse Oximeters 





The probe’s photodetector converts the light, which is partially absorbed and modulated
as it passes through the tissue sample, into an electronic signal. Since HbO2 and Hb allow
different amounts of light to reach the photodetector at the selected wavelengths, the
electronic signal varies depending on which light source is “on” and the oxygenation of
the arterial hemoglobin. The oximeter amplifies the electronic signals received. Analog
and digital signal processing converts the light intensity information into SaO2 and pulse
rate values and displays them on the oximeter front panel.












Functional components

Digital Processing

The microprocessor performs mathematical processes comparing the data from the red
and infrared channels to each other. A ratio of the change in voltage in the red channel
(▲RED) to the change in voltage of the infrared channel (▲IR) over some small interval
of time is used to calculate SaO2. This “instantaneous” oxygen saturation is calculated
30/25 (60/50 Hz) times per second.

A. From theory, oxygen saturation calculates as:


SaO2 = K1R2 + K2R + K3

Where R = ▲RED and K1, K2, K3 are constants
▲IR

where oxygen saturation at any point in time is a function of the change in the red
channel divided by the change in the infrared channel.

The physical optical characteristics of hemoglobin are the basis of the calibration
coefficients: K1, K2 and K3. The oximeter processes the instantaneous oxygen
saturation values to produce the “average saturation values.” The value appears on
the oximeter’s digital display.

One key digital processing function is to properly average the instantaneous
oxygen saturation values. A running average gives a reasonable, but not excellent


84


Developing World Healthcare Technology Laboratory. “Pulse Oximeters.” From the Publication:


“Biomedical Technicians Training Program, Session 3 v2, Special Topics: Cardiac Equipment.”


Engineering World Health, March 1, 2011, p. 1-161.




Pulse Oximeters 




result. A weighted average of instantaneous values provides for a much more
acceptable result. Perfusion at the test site and the current average saturation are
the basis for the weight assigned to each instantaneous calculation. For example,
movement at the probe site can create signal distortion, thus creating some
erroneous instantaneous oxygen saturation values.

Since there are many saturation measurements per second, it is possible to discard
bad values and the displayed saturation remains stable. The weighting function
provides a stable reading, with low sensitivity to motion while retaining the
capability of responding quickly to saturation changes. This running, weighted
average uses data over a 6/3 seconds of data (Slow Mode/Fast Mode) and is
updated every 0.67/0.33 seconds (Slow Mode/Fast Mode).



MODE


SAO2 AVERAGING
PERIOD



Slow
Normal
Fast



12 seconds
6 seconds
3 seconds





A DEFAULT PARAMETER refers to a Volume Level o High/Low alarm limit
automatically set by the oximeter when it is turned on.



Parameters Default Settings Ranges
High SaO2 Limit OFF indicated by “---“ 70 - 100 %
Low SaO2 Limit 90 % 50 – 100%
High Pulse Rate OFF indicated by “---“ 70 – 250 BPM*
Low Pulse Rate 50 BPM 40 – 200 BPM*
Alarm Volume 4 1 - 10
Pulse Volume 4 OFF - 10

*BPM = beats per minute

Perform the following tests daily to assure proper operation of the oximeter.

WARNING: Failure of Operation: If the oximeter fails to respond as described, do NOT
use it until the situation has been corrected by qualified personnel.


85




Pulse Oximeters 







Visual Inspection


1. Inspect the oximeter case for damage.

2. Ensure the display windows are clean.



Functional Inspection


1. Connect a probe to the oximeter. Attach the probe to either finger or ear.

CAUTION: Use ONLY the probes supplied for this model of oximeter. Check
the identification number/serial number tag (A) that is located on the cable
near the connector. The model number must read: MOD 8122-00X or MOD
8121-00X (X represents a digit from 1 through 7).


2. Turn the oximeter on. Verify that the oximeter displays OHMEDA-BIOX
3700/3710 REVISION: X SYSTEM CHECK on the Graphic Display during
the diagnostic self-test. Verify that the status message SYSTEM
OPERATIONAL appears after the diagnostic self-test. Adjust the displays
with the Viewing Angle Thumbwheel Adjustment located under the right side
of the front panel if necessary.



3. Verify that high and low SaO2 and pulse rate alarm limits and readings appear
on the digital display.

4. Verify that the patient alarms are functional. Set the high and low SaO2 and
pulse rate alarm limits beyond the patient readings. Ensure the alarm tone


sounds, and the violated alarm limit and reading flashes on the digital display
and the red alarm light flashes.

5. Verify the Probe Alarms are functional:


A. Remove the probe from the finger or ear. Ensure the Alarm Message
PROBE OFF PATIENT appears on the Graphic Display and the alarm
tone sounds and the red alarm light flashes.

NOTE: The PROBE OFF PATIENT Alarm Message occurs with
the finger probe and the ear probe and may occur with the flex
probes.


B. Unplug the probe from the oximeter. Ensure the Alarm Message NO
PROBE CONNECTED TO UNIT appears on the Graphic Display and
the alarm tone sounds and the red alarm light flashes.


86


Developing World Healthcare Technology Laboratory. “Pulse Oximeters.” From the Publication:


“Biomedical Technicians Training Program, Session 3 v2, Special Topics: Cardiac Equipment.”


Engineering World Health, March 1, 2011, p. 1-161.




2.*Diagrams*and*Schematics*of*Pulse*Oximeters*****Featured*in*this*Section:*****Developing&World&Healthcare&Technology&Laboratory.&“Pulse&Oximeters.”&From&the&Publication:&“Biomedical&Technicians&Training&Program,&Session&3&v2,&Special&Topics:&Cardiac&Equipment.”&Engineering(World(Health,&March&1,&2011,&p.&1N161.&**WHO.&“Pulse&Oximeter&Battery&Powered.”&From&the&publication:&“WHO&Technical&Specifications&for&61&Medical&Devices.&WHO.&Retrieved&from:&http://www.who.int/medical_devices/management_use/mde_tech_spec/en/&*WHO.&“Pulse&Oximeter&Line&Powered.”&From&the&publication:&“WHO&Technical&Specifications&for&61&Medical&Devices.&WHO.&Retrieved&from:&http://www.who.int/medical_devices/management_use/mde_tech_spec/en/&** *






WHO_TS_61_MDs_web.xlsx 45


1


i Version No. 1ii Date of initial version 6/13/12iii Date of last modification 6/18/14iv Date of publicationv Completed / submitted by WHO working group1 WHO Category / Code (under development)2 Generic name Pulse oximeter3 Specific type or variation (optional) line-powered4 GMDN name Pulse oximeter, line-powered5 GMDN code 171486 GMDN category 02 Anaesthetic and respiratory devices , 04 Electro mechanical medical devices , 06 In vitro diagnostic devices 7 UMDNS name Oximeters, Pulse 8 UMDNS code 171489 UNSPS code (optional)10 Alternative name/s (optional) Pulse oxymeter; Oximeter, pulse11 Alternative code/s (optional) MS 34378; MS 4224612 Keywords (optional) SpO2, oxygen, monitor13 GMDN/UMDNS definition (optional) A mains electricity (AC-powered) photoelectric device intended for the continuous transcutaneous measurement and display of haemoglobin oxygen saturation (SpO2). The signals, typically produced by light-emitting diodes (LEDs) and a receiving detector in a probe, or directly built-in, are used to make the measurements using the principle of spectrophotometry. The oximeter displays the SpO2 values and may calculate / display other parameters, e.g., pulse rate, electrocardiogram (ECG). The device is typically used at the bedside. 14 Clinical or other purpose monitor the haemoblobin oxygen saturation of patient, diagnosis for respiratory disorder15 Level of use (if relevant) Health center, district hospital, provincial hospital, specialized hospital16 Clinical department/ward(if relevant) Intensive-care unit, Inpatient ward, Operating room17 Overview of functional requirements Continuously displays patient oxygen saturation in real time using an external probe on the skinContains adjustable alarms to alert when either saturation or heart rate is lowReusable, sterilisable probes are robust and easily connected and disconnectedOperates from mains voltage or from internal rechargeable battery18 Detailed requirements SpO2 measurement range at least 70 to 99 %, minimum gradation 1%Accuracy of SpO2 better than ± 3%Pulse rate range at least 30 to 240 bpm, minimum gradation 1 bpmAccuracy of pulse rate better than ± 5 bpmSignal strength or quality to be visually displayed19 Displayed parameters20 User adjustable settings Audiovisual alarms required: high and low SpO2 and pulse rate (operator variable settings), sensor disconnected, sensor failure, low batteryAlarm override and temporary silence facility to be included21 Components(if relevant) Case is to be hard and splashproofDisplay must allow easy viewing in all ambient light levelsSupplied in protective case for clean storage and safe transport22 Mobility, portability(if relevant)23 Raw Materials(if relevant) N/A24 Electrical, water and/or gas supply (if relevant) Power input to be ************* fitted with ********** compatible mains plugInternal, replaceable, rechargeable battery allows operation for at least four hours in the event of power failureBattery charger to be integral to mains power supply, and to charge battery during mains power operation of unitVoltage corrector / stabilizer / UPS to allow operation at ± 30% of local rated voltageElectrical protection by resettable circuit breakers in both live and neutral supply linesMains supply cable to be at least 3m in length25 Accessories (if relevant) Two reusable probes each for adult, paediatric and infant use26 Sterilization process for accessories (if relevant)27 Consumables / reagents (if relevant)28 Spare parts (if relevant) Two sets of spare fuses (if non-resettable fuses used)29 Other components (if relevant)30 Sterility status on delivery (if relevant)31 Shelf life (if relevant)32 Transportation and storage (if relevant)33 Labelling (if relevant)34 Context-dependent requirements Capable of being stored continuously in ambient temperature of 0 to 50 deg C and relative humidity of 15 to 90%.Capable of operating continuously in ambient temperature of 10 to 40 deg C and relative humidity of 15 to 90%.35 Pre-installation requirements(if relevant)36 Requirements for commissioning (if relevant) Supplier to perform installation, safety and operation checks before handoverLocal clinical staff to affirm completion of installation37 Training of user/s (if relevant) Training of users in operation and basic maintenance shall be providedAdvanced maintenance tasks required shall be documented38 User care(if relevant) The case is to be cleanable with alcohol or chlorine wipes39 Warranty40 Maintenance tasks41 Type of service contract 42 Spare parts availability post-warranty43 Software / Hardware upgrade availability44 Documentation requirements User and maintenance manuals to be supplied in ************** language.Certificate of calibration and inspection to be provided.List to be provided of equipment and procedures required for local calibration and routine maintenanceList to be provided of important spares and accessories, with their part numbers and cost.Contact details of manufacturer, supplier and local service agent to be provided45 Estimated Life Span 7 years46 Risk Classification Class B (GHTF Rule 10);Class II (USA); Class II (EU, Japan, Canada and Australia)47 Regulatory Approval / Certification Must be FDA, CE or UL approved product.
48 International standards ISO 14971:2007 Medical devices -- Application of risk management to medical devices IEC 60601-1:2012 Medical electrical equipment - Part 1: General requirements for basic safety and essential performanceIEC 60601-1-1:2000 Medical electrical equipment - Part 1-1: General requirements for safety - Collateral standard: Safety requirements for medical electrical systemsIEC 60601-1-2:2007 Medical electrical equipment - Part 1-2: General requirements for basic safety and essential performance - Collateral standard: Electromagnetic compatibility - Requirements and tests ISO 80601-2-61:2011 Medical electrical equipment -- Part 2-61: Particular requirements for basic safety and essential performance of pulse oximeter equipmentISO/IEEE 11073-10404:2010 Health informatics -- Personal health device communication -- Part 10404: Device specialization -- Pulse oximeter49 Reginal / Local Standards50 Regulations US regulations 21 CFR part 820 21CFR part 870.2700 oximeter JP regulations MHLW Ordinance No.169 17148010 Pulse oximeter


DOCUMENTATION
DECOMMISSIONINGSAFETY AND STANDARDS


UTILITY REQUIREMENTS
ACCESSORIES, CONSUMABLES, SPARE PARTS, OTHER COMPONENTS
PACKAGING
ENVIRONMENTAL REQUIREMENTSTRAINING, INSTALLATION AND UTILISATION
WARRANTY AND MAINTENANCE


PHYSICAL/CHEMICAL CHARACTERISTICS


MEDICAL DEVICE SPECIFICATIONNAME, CATEGORY AND CODING


PURPOSE OF USE
TECHNICAL CHARACTERISTICS




WHO_TS_61_MDs_web.xlsx 46


1


1 WHO Category / Code (under development)2 Generic name Pulse oximeter3 Specific type or variation (optional) battery-powered4 GMDN name Pulse oximeter, battery-powered (handheld)5 GMDN code 456076 GMDN category 02 Anaesthetic and respiratory devices , 04 Electro mechanical medical devices , 06 In vitro diagnostic devices 7 UMDNS name Oximeters, Pulse 8 UMDNS code 171489 UNSPS code (optional)10 Alternative name/s (optional) Oximeter; Pulse oxymeter; Oximeter, pulse11 Alternative code/s (optional) MS 46612; MS 34378; MS 4224612 Keywords (optional) SpO2, oxygen, monitor, portable13 GMDN/UMDNS definition (optional) A portable, battery-powered, photoelectric device intended for the transcutaneous measurement and display of haemoglobin oxygen saturation (SpO2). The signals, typically produced by light-emitting diodes (LEDs) and a receiving detector in a probe, or directly built-in, are used to make the measurements using the principle of spectrophotometry. The oximeter displays the SpO2 values and may calculate/display other parameters, e.g., pulse rate, electrocardiogram (ECG). The device is typically applied to the fingertip or around the wrist; it may be used by healthcare facilities, emergency services, or in the home. 14 Clinical or other purpose monitor the haemoblobin oxygen saturation of patient, diagnosis for respiratory disorder15 Level of use (if relevant) Health post, health center, district hospital, specialized hospital16 Clinical department/ward(if relevant) Intensive-care unit, Inpatient ward, Operating room17 Overview of functional requirements Displays patient oxygen saturation and pulse rate in real time using an external probe on the skinDisplay and probe built into one caseIntended for time-limited spot checks, so alarm features not requiredOperates from internal battery (locally available type, rechargeable or non-rechargeable)
18 Detailed requirements SpO2 measurement range at least 70 to 99 %, minimum resolution 1%Accuracy of SpO2 better than ± 2%Pulse rate range at least 30 to 240 bpm, minimum gradation 1 bpmAccuracy of pulse rate better than ± 4 bpmSignal strength or quality to be visually displayedAutomatic power-off facility required after minimum of 1 minuteLow battery display requiredFacility for data download preferredDigital equipment with autocorrelation algorithm.19 Displayed parameters Integrated display for data visualization with size not less than 5 inches. Video display of at least the following parameters:a) SpO2 sensor connected;b) alarms disabled;c) low battery;d) battery in charge.12) Plethysmographic curves and tendency lines visualization capabilities for monitored parameters.13) At least the following audio alarms:a) high frequency;b) low frequency;c) low saturation.20 User adjustable settings21 Components(if relevant) Case is to be hard and splashproofDisplay must allow easy viewing in all ambient light levelsSupplied in protective case for clean storage and safe transportHandle bar or facilities for easy transportation.22 Mobility, portability(if relevant)Portable23 Raw Materials(if relevant) N/A24 Electrical, water and/or gas supply (if relevant) Charger electrical source requirements: Amperage: ______; Voltage: ______; Frequency: ______; Phases: ______.Protections against over-voltage and over-current line conditions.Compliance with ______ electrical standards and regulations.Battery charger (if required) to be ************* fitted with ********** compatible mains plugBattery to allow at least eight hours’ continuous operation25 Accessories (if relevant) Battery charger, Batteries Oxymetercable with a length of at least 1.2 m;1 adult patient reusable oxymeter sensors;1 pediatric patient reusable oxymeter sensor;1 neonatal patient reusable oxymeter sensor.26 Sterilization process for accessories (if relevant)27 Consumables / reagents (if relevant)28 Spare parts (if relevant)29 Other components (if relevant)30 Sterility status on delivery (if relevant) N/A31 Shelf life (if relevant) N/A32 Transportation and storage (if relevant) N/A33 Labelling (if relevant) N/A34 Context-dependent requirements Capable of being stored continuously in ambient temperature of 0 to 50 deg C and relative humidity of 15 to 90%.Capable of operating continuously in ambient temperature of 10 to 40 deg C and relative humidity of 15 to 90%.35 Pre-installation requirements(if relevant)36 Requirements for commissioning (if relevant) Supplier to perform installation, safety and operation checks before handoverLocal clinical staff to affirm completion of installation37 Training of user/s (if relevant) Training of users in operation and basic maintenance shall be providedAdvanced maintenance tasks required shall be documented38 User care(if relevant) The case is to be cleanable with alcohol or chlorine wipes39 Warranty40 Maintenance tasks41 Type of service contract 42 Spare parts availability post-warranty43 Software / Hardware upgrade availability44 Documentation requirements User and maintenance manuals to be supplied in ************** language.Certificate of calibration and inspection to be provided.List to be provided of equipment and procedures required for local calibration and routine maintenanceList to be provided of important spares and accessories, with their part numbers and cost.Contact details of manufacturer, supplier and local service agent to be provided45 Estimated Life Span 7 years46 Risk Classification Class B (GHTF Rule 10);Class II (USA); Class II (EU, Japan, Canada and Australia)47 Regulatory Approval / Certification Must be FDA, CE or UL approved product.
48 International standards ISO 13485:2003 Medical devices -- Quality management systems -- Requirements for regulatory purposes (Australia, Canada and EU)ISO 14971:2007 Medical devices -- Application of risk management to medical devices IEC 60601-1:2012 Medical electrical equipment - Part 1: General requirements for basic safety and essential performanceIEC 60601-1-1:2000 Medical electrical equipment - Part 1-1: General requirements for safety - Collateral standard: Safety requirements for medical electrical systemsIEC 60601-1-2:2007 Medical electrical equipment - Part 1-2: General requirements for basic safety and essential performance - Collateral standard: Electromagnetic compatibility - Requirements and tests ISO 80601-2-61:2011 Medical electrical equipment -- Part 2-61: Particular requirements for basic safety and essential performance of pulse oximeter equipmentISO/IEEE 11073-10404:2010 Health informatics -- Personal health device communication -- Part 10404: Device specialization -- Pulse oximeter49 Reginal / Local Standards50 Regulations US regulations 21 CFR part 820 21CFR part 870.2700 oximeter JP regulations MHLW Ordinance No.169 17148010 Pulse oximeter


DOCUMENTATIONDECOMMISSIONINGSAFETY AND STANDARDS


UTILITY REQUIREMENTS
ACCESSORIES, CONSUMABLES, SPARE PARTS, OTHER COMPONENTS
PACKAGING
ENVIRONMENTAL REQUIREMENTSTRAINING, INSTALLATION AND UTILISATION
WARRANTY AND MAINTENANCE


PHYSICAL/CHEMICAL CHARACTERISTICS


NAME, CATEGORY AND CODING


PURPOSE OF USE
TECHNICAL CHARACTERISTICS




3.*Preventative*Maintenance*and*Safety*of*Pulse*Oximeters****Featured*in*this*Section:*****Cooper,&Justin&and&Alex&Dahinten&for&EWH.&“Pulse&Oximeter&Preventative&Maintenance.”&From&the&publication:&Medical(Equipment(Troubleshooting(Flowchart(Handbook.&Durham,&NC:&Engineering&World&Health,&2013.&**Developing&World&Healthcare&Technology&Laboratory.&“Pulse&Oximeters.”&From&the&Publication:&“Biomedical&Technicians&Training&Program,&Session&3&v2,&Special&Topics:&Cardiac&Equipment.”&Engineering(World(Health,&March&1,&2011,&p.&1N161.&




Pulse&Oximeter&Preventative&Maintenance&
Preventive(Maintenance((


• !Inspect(exterior(of(equipment(for(damaged(or"missing"hardware."!• Inspect(the(power(cord,(strain(relief(and(plug/s(for(any(signs(of(damage.(!• Turn%unit%off,%unplug***,%open%user%accessible%covers%and%inspect%unit%for%damage.!• Clean&unit&interior&components&and&exterior&with&compressed&air.!• Inspect(interior$for$signs$of$corrosion$or$missing$hardware.$Repair$as$required.!• Inspect(electrical(components(for(signs(of(excessive(heat(or(deterioration.(!• Clean&exterior&with&warm&water&and&liquid&soap&or&mild%detergent.!• Replace'probe'if'disposable.!• Ensure' nothing' is# blocking# LEDs# or# photodetector# on# probe.# If# blocked,# clean# with#isopropyl( alcohol( solution( or( mild( detergent," mild" chlorine" bleach" solution," hydrogen"peroxide( solution,( or( isopropyl( alcohol.' Do' not' use! acetone,( butyl( alcohol,( denatured(ethanol,) Freon,) trichloroethylene* or* any* petroleum"based& solutions.! Verify' red' light' is'being&emitted&in&probe.!• Place&probe&on&finger&and&make&sure&SpO2!and$heart!rates%(if%applicable)!appear.!• Remove&probe&from&finger&and$verify$that$alarm$is$working.!• Unplug'probe'and'verify#that#alarm#is#working.!• Examine(switches(and(controls(for(proper(function.!• Confirm(lights,(indicators,(and(displays(are(working.!• Verify'machine'can'run'on'line'power'without'battery.!• Check!suggested!replacement!date!for!battery!to!see!if!date!is!passed!or!approaching!and!replace!battery!if!necessary.!&
&!!




Pulse Oximeters 





►IMPORTANT: All patient and probe alarms are audibly suppressed for one
minute, after the SYSTEM OPERATIONAL message.

6. Depress POWER/STANDBY to turn the oximeter off. No displays should be
visible.

Probes


1. Check probes for foreign material such as tape or cotton. Remove any
substances present that may interfere with transmission of light between
the emitter and detector.


2. Verify that the probes open and close smoothly. If there is any unevenness or
variations in the closing motion, replace the probe.


3. Check that the probe is the correct model before connecting it to the oximeter.


CAUTION: Use ONLY the probes supplied for this model of oximeter. Check the
identification number/serial number Tag (A) that is located on the


cable near the connector. The model number must read: MOD 8122-
OOX or MOD 8121-OOX (X represents a digit from 1 through 7).


4. Check that the probe connector makes a firm connection with the oximeter.

5. Check that the probe cable is not twisted.



6. Turn the oximeter on.



7. Check that the red probe LED is lit upon turning the oximeter on.



WARNING: EXPLOSION HAZARD: Do NOT use in the presence of
flammable anesthetics.


SAFETY


A WARNING indicates a potentially harmful situation.

Handle the oximeter equipment with care. Oximeter damage or inaccurate operation may
result from improper handling.

Electrical Shock Hazard: Do NOT remove top cover. Refer to qualified personnel.

Failure of Operation: If the oximeter fails to respond as described, do NOT use it until the
situation has been corrected by qualified personnel.


87


Developing World Healthcare Technology Laboratory. “Pulse Oximeters.” From the Publication:


“Biomedical Technicians Training Program, Session 3 v2, Special Topics: Cardiac Equipment.”


Engineering World Health, March 1, 2011, p. 1-161.




Pulse Oximeters 




Explosion Hazard: Do NOT use in the presence of flammable anesthetics.

Data Validity: Do NOT expose the probe detector to strong ambient light while it is being
used to monitor a patient. A poor signal may result.

Data Validity: Do NOT attach a probe to the same limb with an inflated blood pressure
cuff. Valid data will NOT be received when the cuff is inflated. Attach probe to the limb
opposite the site used for the blood pressure cuff.

Patient Safety: Patient condition may require changing the probe test site periodically.
This should diminish the possibility of pressure necrosis of the test site.

Patient Safety: LEDs (Light Emitting Diodes) generate a small amount of heat as a by-
product of light emission. Although the rise in temperature is minimal, the probe should
be checked periodically in the event of long term monitoring.

Patient Safety: The ear probe should be moved to the opposite ear periodically if it is
used for long term monitoring.

Patient Safety: Exercise extreme care to assure continued circulation distal to probe site
after application.

Electrical Shock Hazard: Always unplug the oximeter before cleaning.

Data Validity: Do NOT operate the oximeter unless it is properly calibrated. Inaccurate
patient SaO2 readings will result.


A CAUTION indicates a condition that may lead to
equipment damage or malfunction.



Do NOT apply tension to the probe cable. Probe damage may result.

Check rear panel voltage setting before connecting the oximeter to AC main power.

Avoid storing the oximeter and probes at temperatures exceeding 20°C (-4°F) to 60° C
(140°F).

Connect only a high impedance device (1K Ohm or higher) to the analog output jacks.
Improper loading will upset the correspondence between the measured voltage and the
intended output voltage.

Never immerse the oximeter in liquid.

Do NOT autoclave the oximeter.

Do NOT gas sterilize the oximeter.


88


Developing World Healthcare Technology Laboratory. “Pulse Oximeters.” From the Publication:


“Biomedical Technicians Training Program, Session 3 v2, Special Topics: Cardiac Equipment.”


Engineering World Health, March 1, 2011, p. 1-161.




Pulse Oximeters 





Do NOT soak or immerse the probes in any liquid solution.

Do NOT autoclave probes.

Following sterilization with ethylene oxide, probes should be quarantined in a well-
ventilated area to allow dissipation of residual ethylene oxide gas absorbed by the probe.
Follow sterilizer manufacturer’s recommendations for specific aeration periods required.

Do NOT turn on the oximeter after the RECHARGE BATTERY alarm condition is
displayed without plugging it into AC main power. Operating the oximeter on battery
power during a RECHARGE BATTERY alarm condition may permanently damage the
lead-acid battery.

No repair should be undertaken or attempted by unqualified personnel.

Use hospital-grade grounded receptacle only.

















FRONT PANEL

A. GRAPHIC DISPLAY: This displays the Signal Strength Indicator, Response Mode
Information, Battery Status Information, Plethysmographic Waveform, Trend Data,
Status Messages, and Alarm Messages.


1. SGNL” SIGNAL STRENGTH INDICATOR – The signal strength Bar Graph


provides a visual indication of the received pulsatile signal. The higher the bar,
the stronger the signal. The height of the bar is determined by several factors
including tissue perfusion at the probe site, and the capability of the tissue under
test to pass the incident light. If the bar is 5 pixels or less continuously for 5


89




4.*Troubleshooting*and*Repair*of*Pulse*Oximeters*****Featured*in*this*Section:****Cooper,&Justin&and&Alex&Dahinten&for&EWH.&“Pulse&Oximeter&Troubleshooting&Flowchart.”&From&the&publication:&Medical(Equipment(Troubleshooting(Flowchart(Handbook.&Durham,&NC:&Engineering&World&Health,&2013.&** Strengthening&Specialised&Clinical&Services&in&the&Pacific.&User(Care(of(Medical(Equipment:(A(first(line(maintenance(guide(for(end(users.&(2015).&* *




Pulse&Oximeter&Repair&and&Troubleshooting&
&
&Flowchart*!! !




Description*#! Text&Box! Explanation&or&Comment!
1! Begin:!Pulse!Oximeter! Begin!diagnostic!process!on!a!work!order!for!pulse!oximeter.!Maintenance!is!generally!requested!on!a!pulse!oximeter!when!it!cannot!read!SpO2!or!heart!rate!levels.!2! Does!the!pulse!oximeter!power!on?! The!displays!should!appear!on!working!pulse!oximeter!when!powered!on.!!
3! Troubleshoot!power!supply!(separate!chart).! If!no!power!reaches!the!machine,!there!may!be!problems!with!the!switch,!fuse,!or!wiring.!See!flowchart!for!Power!Supply!and!BTA!skills!on!Power!Supply.!
4! Does!the!pulse!oximeter!power!on!with!the!battery!only?! Though!the!machine!can!still!be!used!even!if!the!battery!charging!circuit!is!faulty,!the!battery!should!be!checked!for!functionality.!
5! Test!battery!voltage.! Use!a!multimeter!to!determine!if!proper!voltage!is!reaching!the!pulse!oximeter.!See!flowchart!for!Batteries!and!BTA!skills!on!Power!Supply.!6! Charge!battery!if!needed!by!plugging!into!wall.! The!battery!needs!fourteen!hours!to!recharge!completely.!!7! Does!the!battery!charge?! If!the!battery!does!not!hold!charge,!the!machine!may!still!be!used!when!plugged!in.!8! Check!battery!charging!circuit.! Ensure!that!the!circuitry!that!charges!the!battery!is!intact.!9! Change!battery!if!needed.! Check!the!battery’s!replacement!date!and!change!it!if!it!is!faulty!or!if!the!date!has!passed.!10! Go!to!begin.! Restart!the!diagnostic!process!to!see!if!the!corrective!measures!have!repaired!the!machine.!11! Disconnect!probe.! Remove!probe!from!pulse!oximeter.!
12! Does!the!alarm!sound?! The!alarm!should!not!only!sound!when!heart!rate!or!SpO2!levels!reach!outside!the!acceptable!ranges!but!when!the!probe!connection!with!the!machine!is!lost.!13! Check!connection.! Ensure!that!there!is!nothing!blocking!the!probe!




receptacle.!Clear!any!debris!or!dirt!that!may!interfere!with!probe!connection.!
14! Check!internal!circuitry!and!speakers.! Ensure!internal!circuitry!and!speaker!connections!are!intact.!See!BTA!skills!for!Electrical!Simple.!15! Reconnect!probe.! Reinsert!probe!into!pulse!oximeter.!
16! Does!the!alarm!stop!sounding?! Ensure!that!the!probe!connection!alarm!stops!when!the!probe!is!reconnected.!
17! Check!probe!connector.!Replace!if!pins!are!damaged.! If!the!pins!on!the!probe!connector!are!damaged,!bent,!or!broken,!the!probe!should!be!replaced.!
18! If!probe!is!still!not!being!recognized,!replace!probe.! If!the!alarm!continues,!the!problem!may!be!with!the!probe!itself.!Replace!the!probe.!
19! Is!one!light!sensor!visible!in!the!probe?! There!should!be!one!red!light!being!visibly!emitted!from!inside!the!probe.!
20! Clean!probe!with!a!70%!isopropyl!alcohol!solution!or!a!mild!detergent.!


Probe!can!also!be!cleaned!with!warm!water,!liquid!soap,!mild!chlorine!bleach!solution,!or!a!hydrogen!peroxide!solution.!Do!not!use!acetone,!butyl!alcohol,!denatured!ethanol,!Freon,!trichloroethylene!or!any!petroleum\based!solutions.!See!BTA!skills!on!Mechanical!Cleaning.!
21! Replace!probe!if!light!is!still!not!visible.! If!light!is!not!being!emitted,!the!photodetector!cannot!read!the!signals.!The!pulse!oximeter!cannot!calculate!the!SpO2!value!or!heart!rate.!
22! Place!probe!on!finger.!Ensure!ambient!light!cannot!enter!sensor.!


When!not!in!use,!the!probe!should!be!shielded!from!direct!light.!If!any!outside!light!enters!the!sensor,!it!can!drastically!affect!readings,!as!they!are!calculated!through!photodetection!sensors.! !
23! Does!SpO2!rate!(and!heart!rate,!if!applicable)!appear!when!probe!is!placed!on!finger?!


The!rate(s)!should!appear!on!the!display!one!the!probe!is!placed!on!the!finger.!
24! Reposition!probe!on!finger.! The!probe!may!be!placed!incorrectly!on!the!finger.!Ensure!it!is!not!too!tight!or!loose!and!no!outside!light!is!entering!the!sensor.!




25! If!readings!still!do!not!appear,!check!internal!circuitry.! Ensure!internal!circuitry!is!intact!and!connections!are!strong.!See!BTA!skills!on!Electrical!Simple.!
26! If!readings!still!do!not!appear,!replace!probe.! Ensure!correct!probe!is!being!used.!Other!probes!may!not!connect!correctly.!
27! Hold!breath!for!10\20!seconds.! This!is!to!manually!check!if!the!SpO2!readings!decrease!with!less!oxygen!supply.!
28! Do!SpO2!levels!decrease!to!under!95%!(or!at!least!by!2%)?! As!you!hold!your!breath!longer,!the!rate!should!decrease!a!few!percent!at!least.!!29! Replace!probe.! Attempt!again!with!a!new!probe.!
30! If!applicable,!calculate!true!heart!rate!using!stopwatch/neck!artery!technique.!


If!applicable,!calculate!heart!rate!manually!using!a!stopwatch!and!counting!pulse!rate!of!neck!artery!(or!wrist).!
31! Do!heart!rate!values!match!to!within!1bpm?! Compare!manually!calculated!values!to!pulse!oximeter!display.!32! Replace!probe.! If!values!are!not!with!1bpm,!replace!probe.!
33! Pulse!oximeter!is!working!properly.! Return!the!machine!to!the!appropriate!clinical!personnel.!!
& !*




User Care of Medical Equipment – First line maintenance for end users


49


Troubleshooting – Pulse Oximeters


Fault Possible Cause Solution


1.



Equipment is not running



No power from mains socket







Battery (if present) is discharged

Electrical cable fault





Check power switch is on.
Replace fuse with correct voltage
and current if blown.
Check mains power is present at
socket using equipment known to
be working. Contact electrician
for rewiring if power not present.

Recharge or replace battery

Try cable on another piece of
equipment. Contact electrician
for repair if required.



2.



SpO2 or pulse rate not displayed
or unstable



Probe is not mounted correctly

Probe not able to read through
dirt, nail polish, etc.

Patient movement

Patient‟s SpO2 value is too low to
be measured

Internal malfunction



Connect probe and cable properly

Remove grease, dirt, nail polish
and clean probe

Request patient to remain still

Further clinical examination of
patient. Resite probe if necessary

Call biomedical technician.



3.



“Probe off” displayed on screen





Probe is not connected properly

The connection between the
probe and oximeter is loose



Connect the sensor

Refer to biomedical technician for
repair



4.



“Error” displayed on screen



Faulty probe or control circuit



Refer to biomedical technician



5.



Continuous alarm sounds



Alarm limits set too low or high

Power disconnected

Internal malfunction



Set appropriate alarm limits

Connect power cable

Refer to biomedical technician



6.



Electrical shocks



Wiring fault



Refer to biomedical technician
immediately




User Care of Medical Equipment – First line maintenance for end users


50


User Care Checklist – Pulse Oximeters


Daily

Cleaning



9 Remove any dust / dirt

9 Remove any tape, paper or foreign body from equipment

9 Clean probe with alcohol wipe after each use




Visual checks



9 Check all parts are present and connected

9 Check cables are not twisted and remove from service if any


damage is visible



Function
checks



9 Check operation on healthy subject before use



9 Store probe and cable carefully, replace equipment cover






Weekly

Cleaning



9 Unplug, clean outside with damp cloth and dry off




Visual checks



9 Check all screws and parts are fitted tightly

9 If plug, cable or socket are damaged, replace



Function
checks



9 Check operation of all lights, indicators and visual displays

9 Check probe disconnection alarm.




Every six months
Biomedical Technician check required




** 5.*Resources*for*More*Information*about*Pulse*Oximeters****Featured*in*this*Section:****Malkin,&Robert.&“Pulse&Oximeter:&Use&and&Operation.”&Medical(Instrumentation(in(the(Developing(World.&Engineering&World&Health,&2006.&& *&& &**&&&&* *&&&&&




*Resources*for*More*Information:&*&&Internal*Resources*at*library.ewh.org:*For*More*Information*about*pulse*oximeters,*please*see*this*resource*in*the*BMET*Library!*& 1. Malkin,&Robert.&“Pulse&Oximeter:&Use&and&Operation.”&Medical(Instrumentation(in(the(Developing(World.&Engineering&World&Health,&2006.&&&&




Pulse*Oximeter*Bibliography:&&&&Developing&World&Healthcare&Technology&Laboratory.&“Pulse&Oximeters.”&From&the&Publication:&“Biomedical&Technicians&Training&Program,&Session&3&v2,&Special&Topics:&Cardiac&Equipment.”&Engineering(World(Health,&March&1,&2011,&p.&1N161.&&&&Cooper,&Justin&and&Alex&Dahinten&for&EWH.&“Pulse&Oximeter&Preventative&Maintenance.”&From&the&publication:&&Medical(Equipment(Troubleshooting(Flowchart(Handbook.&Durham,&NC:&Engineering&World&Health,&2013.&&&Cooper,&Justin&and&Alex&Dahinten&for&EWH.&“Pulse&Oximeter&Troubleshooting&Flowchart.”&From&the&publication:&Medical(Equipment(Troubleshooting(Flowchart(Handbook.&Durham,&NC:&Engineering&World&Health,&2013.&* Strengthening&Specialised&Clinical&Services&in&the&Pacific.&User(Care(of(Medical(Equipment:(A(first(line(maintenance(guide(for(end(users.&(2015).&&&Wikipedia.&“Pulse&Oximeter.”&Wikipedia,&p.&1N4.&Retrieved&from:&https://en.wikipedia.org/wiki/Pulse_oximetry&*&WHO.&“Pulse&Oximeter&Battery&Powered.”&From&the&publication:&“WHO&Technical&Specifications&for&61&Medical&Devices.&WHO.&Retrieved&from:&http://www.who.int/medical_devices/management_use/mde_tech_spec/en/&*WHO.&“Pulse&Oximeter&Line&Powered.”&From&the&publication:&“WHO&Technical&Specifications&for&61&Medical&Devices.&WHO.&Retrieved&from:&http://www.who.int/medical_devices/management_use/mde_tech_spec/en/&*&WHO.&“Using&the&Pulse&Oximeter,&Tutorial&2&–&Advanced.”&World(Health(Organization,&2011.&&* *




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