WHO_TS_61_MDs_web.pdf

Equipment*Packet:*Fetal&Doppler&and&Fetal&Monitor*UMDNS*#:&11692& &535&Date*of*Creation:&November&13,&2015&Creator:&Complied&by&Cassandra&Stanco&for*Engineering&World&Health&(EWH)***Equipment*Packet*Contents:*This&is&a&twoKpart&packet&that&contains&information&about&the&operation,&maintenance,&and&repair&of&fetal&monitors&and&fetal&Doppler.&Section&A&of&this&packet&discusses&fetal&monitors&and&Section&B&of&this&packet&discusses&fetal&Doppler.&&Part*I:*External*From*the*Packet:*1. An*Introduction*to*Fetal*Monitors:&PowerPoint**Part*II:*Included*in*this*Packet:** Section*A:*Fetal*Monitor*1. Operation*and*Use:*a. Brief&Overview:&Fetal&Monitor&(p.&4)*b. Operation&and&Use&of&Fetal&Monitors&(p.&5K10)*2. Diagrams*and*Schematics:*a. Figure&1:&Proper&Placement&of&Fetal&Monitor&Electrodes&(p.&12)*b. Figure&2:&&Examples&of&Readings&from&Fetal&Monitors&(p.&13K15)*c. Figure&3:&WHO&Specification&for&Neonatal&Physiological&Monitors&(p.&16K18)*3. Preventative*Maintenance*and*Safety:*a. Fetal&Monitor&Preventative&Maintenance&(p.&20)&4. Troubleshooting*and*Repair:**a. Fetal&Monitor&Troubleshooting&Flowchart&(p.&22K25)&& Section*B:*Fetal*Doppler*5. Operation*and*Use:*a. Brief&Overview:&Fetal&Heart&Detector,&Ultrasonic&(p.&28)&b. The&Doppler&Effect&(p.&29K35)&c. Operation&and&Use&of&Fetal&Monitor&and&Fetal&Doppler&(p.&36K38)&6. Diagrams*and*Schematics:*a. Figure&4:&Fetal&Heart&Activity&Signals&(p.&40)&b. Figure&5:&The&Fetal&Circulatory&System&(p.&41)&c. Figure&6:&WHO&Specification&for&Foetal&Heart&Detector&(p.&42K44).&7. Resources*for*More*Information*a. Bibliography&(p.&46K47)*&




*****SECTION*A:*Fetal*Monitors* *




**1.*Operation*and*Use*of*Fetal*Monitors****Featured*in*this*Section:** *Developing&World&Healthcare&Technology&Laboratory.&“Fetal&Monitors.”&From&the&Publication:&“Biomedical&Technicians&Training&Program,&Session&3&v2,&Special&Topics:&Cardiac&Equipment.”&Engineering'World'Health,&March&1,&2011,&p.&115K159.&& &WHO.&“Fetal&Monitor.”&From&the&publication:&Core'Medical'Equipment.&Geneva,&Switzerland,&2011.&&&WHO.&“Neonatal&Physiological&Monitor.”&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/&&& &




http://www.who.int/medical_devices/en/index.html
© Copyright ECRI Institute 2011 (not including the GMDN code and device name).


Reproduced with Permission from ECRI Institute’s Healthcare Product Comparison System.


© Copyright GMDN Agency 2011. GMDN codes and device names are reproduced with permission from the GMDN Agency.


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Electronic fetal monitoring (EFM) provides graphic and numeric
information on fetal heart rate (FHR) and maternal uterine
activity (UA) to help clinicians assess fetal well-being before and
during labor. FHR often exhibits decelerations and accelerations
in response to uterine contractions or fetal movements; certain
patterns are indicative of hypoxia. Examination of these patterns,
the baseline level, and variability characteristics can indicate
the need to alter the course of labor with drugs or perform an
operative delivery.


Product description
Fetal monitors are bedside units that consist of a monitoring unit,
cables, and electrodes. They are designed to measure, record, and
display FHR, uterine contractions, and/or maternal blood pressure
and heart rate before and during childbirth. These monitors
may sense FHR and uterine contraction indirectly through the
mother’s abdomen and/or directly by placing an electrode on
the fetal scalp (or other exposed skin surface) and measuring the
change in pressure within the uterus. Antepartum fetal monitors
are typically used in physician’s offi ces and clinics long before the
beginning of labor. Most hospital-based monitors have additional
capabilities, including fetal and maternal ECG recording.


Principles of operation
Fetal monitors detect FHR externally by using an ultrasound
transducer to transmit and receive ultrasonic waves; the
frequency (or Doppler) shift of the refl ected signal is proportional
to the velocity of the refl ecting structure—in this case, the fetal
heart. A transducer contains one or more piezoelectric elements
that convert an electrical signal into ultrasonic energy that can
be transmitted into tissues. When this ultrasonic energy is
refl ected back from the tissues, the transducer reconverts it to
an electrical signal that can be used to create a waveform for
display and recording and an audible FHR (sound created by the
frequency shift of the ultrasonic signal).


Operating steps
Continuous electronic FHR monitoring can be performed
indirectly, by applying an ultrasound transducer to the mother’s
abdomen, or directly, by attaching an electrode assembly to
the fetus after rupture of the amniotic membranes. Uterine
contractions can be recorded along with FHR by placing a
pressure transducer on the mother’s abdomen or by directly
measuring the change in pressure in the uterus with a catheter.


Reported problems
Common errors include doubled or halved rates, masked
fetal arrhythmias, and presentation of the maternal heart
rate as the FHR. Another error is the report of false FHR
decelerations during uterine contractions due to ultrasonic
signal-processing circuits holding the last FHR on occasional
signal peaks during noisy signals. Reported complications


of fetal scalp electrode application include
infection, uterine perforation, and soft tissue
injuries; mostly resulting from poor technique.
Some investigators have expressed concern
about the possible risks associated with fetal
exposure to ultrasound.


Use and maintenance
User(s): Physicians, obstetric nurses,
community midwives


Maintenance: Biomedical or clinical engineer/
technician, medical staff, manufacturer/servicer


Training: Initial training by manufacturer,
operator’s manuals, user’s guide


Environment of use
Settings of use: Obstetrics (hospital, OB/GYN
practices), emergency medicine


Requirements: Uninterruptible power source,
battery backup, appropriate transducer/
electrodes/sensors


Product specifi cations
Approx. dimensions (mm): 100 x 150 x 200
Approx. weight (kg): 6
Consumables: Batteries, cables, electrodes/
sensors, gel
Price range (USD): 1,200 - 15,000
Typical product life time (years): 8
Shelf life (consumables): NA


Types and variations
Tabletop, cart, some portable


Fetal monitor
UMDNS GMDN
18339
18340


Monitors, Bedside, Fetal, Antepartum
Monitors, Bedside, Fetal, Intrapartum


43958 Foetal cardiac monitor


Other common names:
Cardiotocographs; fetal electrocardiogram (ECG) monitors; fetal heart rate monitors; ultrasonic fetal monitors; Monitor,
cardiac, fetal; Monitor, heart valve movement, fetal, ultrasonic; Monitor, phonocardiographic, fetal.




Fetal Monitors 




Fetal Monitors
Introduction

There are six types of measurements that can be made with the fetal monitor: four to
measure fetal heart rate (FHR) and two for uterine activity (UA). The techniques selected
for a particular patient depend on the clinical assessment of the needs of the patient and
the personal preferences of the staff. The monitor also computes and records heart rate
variability and uterine activity units from data obtained with direct modes. These modes
can be further subdivided into two categories:


A. External – Patient connections are made on the material abdomen. The
fetal heart rate (FHR) external modes include abdominal
electrocardiogram (AFECG), phono, and ultrasound. A
relative measure of uterine activity is obtained by means of a
tocotransducer.
B. Internal --In the internal mode (FECG), FHR is determined from
measurements obtained by electrodes attached to the fetal
presenting part. Uterine activity is measured by means of an
intrauterine catheter and strain gauge.

Each technique has advantages and disadvantages that must be weighed against the
condition of the patient and the data desired.

Only properly trained and qualified personnel should be permitted access to any internal
parts of this equipment.

WARNING: LIVE ELECTRICAL TERMINALS AND COMPONENTS CAN
PRESENT A SHOCK HAZARD TO UNTRAINED PERSONNEL. FAILURE TO
HEED THESE WARNINGS COULD RESULT IN SERIOUS ELECTRICAL
SHOCK INJURIES.

Patient safety

As with all patient monitoring devices, reasonable caution must be exercised with
equipment and patient connections. When properly followed, the following procedures
will ensure maximum patient safety.

Leakage current

Leakage current, which flows from the frame of the equipment to ground, is present in all
electronics equipment. Most monitors are equipped with isolated inputs, and leakage
current is limited to a few microamperes even if full power-line voltage is applied to the
patient leads. However, for maximum patient safety, the following procedures are
recommended.

x Do not touch the patient while making adjustments on the monitor.


115




Fetal Monitors 





x Do not allow patient cables to come in contact with grounded items.

x Keep equipment clean and free of transducer gel, EKG electrode cream, and other


lubricants.

x Do not operate if unit is wet due to spills or condensation. Condensation could occur


if a monitor is moved from building to building.

x Monitors should be plugged into the same circuit as other equipment in use on the


same patient. Your hospital engineering staff should identify outlets that are on the
same circuit in patient areas.



Direct Measuring Hazards

When using direct measuring techniques, there are some potential hazards that must be
considered.

Do not re-use any disposable product.

This equipment is not designed for use in an explosive atmosphere, in the presence of
concentrations of inflammable anesthetics, or inside an oxygen tent. Use in such
atmospheres may present an explosion hazard.

Repairs to this equipment should be made only by authorized personnel. All repairs or
changes to equipment must be entered on a repair record form, along with the data and
signature of repairer.

In all cases, should questions arise, consult the operator’s manual for your particular
monitor.


Figures 1 and 2 on the following pages show the front and back panel displays of a fetal
monitor. A wide variety of accessories is available for fetal monitors. These are featured
in figures 3 and 4.











116




Fetal Monitors 





Figure 0-1: Front panel, fetal monitor
























































117




Fetal Monitors 






Figure 0-2: Rear panel, fetal monitor






















































118




Fetal Monitors 






Figure 0-3: Accessories for fetal monitor






















































119




Fetal Monitors 






Figure 0-4: Additional accessories for fetal monitor






















































120




**2.**Diagrams*and*Schematics*of*Fetal*Monitors&***Featured*in*this*Section:****Developing&World&Healthcare&Technology&Laboratory.&“Fetal&Monitors.”&From&the&Publication:&“Biomedical&Technicians&Training&Program,&Session&3&v2,&Special&Topics:&Cardiac&Equipment.”&Engineering'World'Health,&March&1,&2011,&p.&115K159.&






Fetal Monitors 




Waveform Examples

The following waveform examples illustrate various patterns that may be presented on
the CRT.


1. EXCELLENT-QUALITY SIGNAL. FECG/MECG pattern where FECG is
clearly defined. FECG (F) is clearly distinguished from noise signals and from
much larger MECG. FECG/MECG signals that are coincident © are also
illustrated.





















2. GOOD QUALITY SIGNAL. Noise signals are more evident. FECG (F) is


still clearly distinguishable.


















129




Fetal Monitors 





3. FAIR-QUALITY SIGNAL. FECG sometimes obliterated by sporadic


electrical noise. Some monitors edit these signals (in EDIT) mode and obtain
and display FECG.

















4. POOR-QUALITY SIGNAL. FECG/MECG patterns, where excessive noise


completely obliterates the fetal signal on the monitor display. Some monitors
may still obtain and present FHR on the strip chart recorder, but normally a
visibly discernible fetal signal is required.




























130




Fetal Monitors 







5. NO FETAL SIGNAL. No discernible FECG. Perform search process until
acceptable FECG is obtained, or use alternate method to obtain FHR
recording.


















Search Procedure

If a good recording is not obtained with original electrode positions, a search procedure
must be performed.

Each time the electrode is positioned, wait for AGC to optimize the signal.

If the signal is still not acceptable after the three electrodes have been moved, another
measurement technique should be used.

Edit/unedit modes of operation

The use of electronic logic and pulse insertion makes the FHR record cosmetically
acceptable. However, the actual proportion of accurate event-to-event FHR data may be
quite small. It is difficult to separate precise from imprecise event-to-event FHR data on a
record so treated.

To aid the medical staff in their evaluation of edited and unedited FHR records, the EDIT
and UNEDIT modes of operation are described.









131




WHO_TS_61_MDs_web.xlsx 34


1


i Version No. 1ii Date of initial version 8/27/12iii Date of last modification 7/4/14iv Date of publicationv Completed / submitted by WHO working group1 WHO Category / Code (under development)2 Generic name Neonatal physiological monitor3 Specific type or variation (optional)4 GMDN name Neonatal physiologic monotoring systems5 GMDN code 355696 GMDN category Anaesthetic and respiratory devices , Electro mechanical medical devices7 UMDNS name Monitors, Bedside, Physiologic, Neonatal 8 UMDNS code 157919 UNSPS code (optional)10 Alternative name/s (optional) Physiologic monitoring system; Neonatal patient monitor; Physiologic monitoring system, neonatal11 Alternative code/s (optional) MS 12636; S 34379; S 1579112 Keywords (optional) patient monitor, ECG, EKG, vital signs, physiological
13 GMDN/UMDNS definition (optional)


A device assembly designed to continuously measure and display multiple vital physiological parameters of newborn and premature infants, especially those under critical care. It is typically capable of monitoring parameters such as electrocardiogram (ECG), respiration rate, heart rate, blood pressure, and body temperature; it may also assess haemoglobin oxygen saturation (SpO2) through transcutaneous sensors that measure both transcutaneous oxygen (tcpO2) and transcutaneous carbon dioxide (tcpCO2) saturation. The system typically includes sensors with appropriate size and design for infant use.
14 Clinical or other purpose Designed to continuously measure and display multiple vital physiological parameters of newborn and premature infants, especially those under critical care. 15 Level of use (if relevant) district hospital, provincial hospital, specialized hospital16 Clinical department/ward(if relevant) Neonatal intensive care unit (NICU), Emergency room (ER), Operating Theatre17 Overview of functional requirements Continuous display on screen of neonatal or infant ECG, respiration and heart rates, invasive / non-invasive blood pressure, body temperature and SpO2.
18


Detailed requirements Hard copy printout of traces will not be required. Heart rate measurement range to be at least 30 to 250 bpm, with accuracy better than ± 5 bpm and minimum gradation 1 bpm.SpO2 measurement range at least 70 to 99 %, with accuracy better than ± 3% and minimum gradation 1%.NIBP blood pressure monitoring range at least 30 to 300 mmHg, minimum gradation 1 mmHg.Respiration rate measurement range at least 0 to 100 bpm, minimum gradation 1 bpmTemperature range at least 30 to 40 deg C, minimum gradation 0.1 deg C.
19


Displayed parameters Multichannel (up to 12 leads) ECG measurement and selectable display.Allows display of single, 3 lead ECG or simultaneous display of at least 3 waves selected from up to 12 points.Unwanted parameters can be deselected from display.Display to be digital of all active parameters and trace display of at least three selectable parameters.Trend display of each parameter over at least previous 24 hours to be selectableDisplay must allow easy viewing in all ambient light levels.
20 User adjustable settings Operator can set audio visual alarm levels for low or high levels of each parameter independently.User operated 1mV ECG test marker function requiredAlarm override and temporary silence facility to be included. Audio Visual alarms required: high and low levels for each parameter (operator variable settings), sensor / wire / probe disconnected, low batteryPHYSICAL/CHEMICAL CHARACTERISTICS


MEDICAL DEVICE SPECIFICATION
NAME, CATEGORY AND CODING


PURPOSE OF USE


TECHNICAL CHARACTERISTICS




WHO_TS_61_MDs_web.xlsx 34


2


21 Components(if relevant) Case is to be hard and splash proof. Cable connectors to be designed so as fit correct socket onlyWired patient cable connections will be preferred above wireless connection 22 Mobility, portability(if relevant)Supplied in protective case for clean storage and safe transport23 Raw Materials(if relevant)
24


Electrical, water and/or gas supply (if relevant) Power input to be ************* fitted with ********** compatible mains plugBattery charger to be integral to mains power supply, and to charge battery during mains power operation of unit.Battery powered, silenceable alarm for power failure.Internal, replaceable, rechargeable battery allows operation for at least one hour in the event of power failure. Voltage corrector / stabilizer to allow operation at ± 30% of local rated voltage.Electrical protection provided by fuses in both live and neutral supply linesMains cable to be at least 3m length
25


Accessories (if relevant) 12 lead ECG cable. ECG patient connectors that are sterilisable and reusable are preferred, though reusable cables that attach to disposable connection patches are also acceptable.5 sets of ECG connection electrodes (if reusable type), 100 sets of ECG connection electrodes (if disposable type) shall be supplied. 5 tubes electrode gel (if required).5 lead ECG cable (if option offered).Two reusable SpO2 probes each for neonatal and infant use.Blood pressure – invasive: one sensor for each channel offered; non-invasive: two reusable neonatal cuffs.Two reusable, external skin temperature probes.26 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).List to be provided of other important spares and accessories, with their part numbers and cost.29 Other components (if relevant)An extra option for simple five lead connection would be preferred.
30 Sterility status on delivery (if relevant)31 Shelf life (if relevant)32 Transportation and storage (if relevant)33 Labelling (if relevant) Unit shall be supplied protectively packed for safe onward shipping
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 handover.Local clinical staff to affirm completion of installation37 Training of user/s (if relevant) Training of users in operation and basic maintenance shall be provided.38 User care(if relevant) The case is to be cleanable with alcohol or chlorine wipes.
39 Warranty Duration of warranty to be stated, minimum one year. Specific inclusions and exclusions to be listed.One service visits shall be made under warranty.Contact details of manufacturer, supplier and local service agent to be provided


UTILITY REQUIREMENTS


ACCESSORIES, CONSUMABLES, SPARE PARTS, OTHER COMPONENTS


PACKAGING
ENVIRONMENTAL REQUIREMENTS
TRAINING, INSTALLATION AND UTILISATION


WARRANTY AND MAINTENANCE




WHO_TS_61_MDs_web.xlsx 34


3


40 Maintenance tasks List shall be provided of equipment and procedures required for local calibration and routine maintenanceAdvanced maintenance tasks required shall be documented41 Type of service contract Costs and types of post-warranty service contract available shall be described.42 Spare parts availability post-warrantyGuaranteed time period of availability of spare parts post-warranty shall be described.43 Software / Hardware upgrade availabilityGuaranteed time period of support and software upgrade (if relevant) availability post-warranty shall be described.
44 Documentation requirements User, technical and maintenance manuals to be supplied in ************** language. Supplier to describe any materials contained in the device that are classified as hazardous under local regulations.45 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 Shall 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 IEC 60601-1-8 :2012 (Part 1-8: General requirements for basic safety and essential performance - Collateral Standard: General requirements, tests and guidance for alarm systems in medical electrical equipment and medical electrical systems)IEC 60601-2-49:2011 (Part 2-49: Particular requirements for the basic safety and essential performance of multifunction patient monitoring equipment)Optional:IEC 60601-2-23:2011 (Part 2-23: Particular requirements for the basic safety and essential performance of transcutaneous partial pressure monitoring equipment)IEC 60601-2-26:2012 (Part 2-26: Particular requirements for the basic safety and essential performance of electroencephalographs)IEC 60601-2-27:2011 (Part 2-27: Particular requirements for the basic safety and essential performance of electrocardiographic monitoring equipment)IEC 60601-2-34:2011 (Part 2-34: Particular requirements for the basic safety and essential performance of invasive blood pressure monitoring equipment)IEC 60601-2-40:1998 (Part 2-40: Particular requirements for the safety of electromyographs and evoked response equipment)IEC 60601-2-47:2012 (Part 2-47: Particular requirements for the basic safety and essential performance of ambulatory electrocardiographic systems)IEC 80601-2-30:2009 (Part 2-30: Particular requirements for the basic safety and essential performance of automated non-invasive sphygmomanometers)ISO 80601-2-55:2011 (Part 2-55: Particular requirements for the basic safety and essential performance of respiratory gas monitors)ISO 80601-2-61:2011 (Part 2-61: Particular requirements for basic safety and essential performance of pulse oximeter equipment)
49


Reginal / Local Standards AAMI/ANSI EC38:2007 (Part 2-47: Particular requirements for the safety, including essential performance, of ambulatory electrocardiographic systems)IEEE Std 11073-10406-2011 (Health informatics - Personal health device communication Part 10406: Device specialization - Basic electrocardiograph)EN 12470-4:2000 Clinical thermometersPerformance of electrical thermometers for continuous measurementJIS T 1115:2005 Non-invasive Automated SphygmomanometersJIS T 3323:2008 Pressure transducers
50 Regulations US regulations 21 CFR part 820 21CFR section 870.1025 monitor, physiological, patient(with arrhythmia detection or alarms) JP regulations MHLW Ordinance No.169 35569000 Neonatal monitor


DOCUMENTATION
DECOMMISSIONINGSAFETY AND STANDARDS




3.*Preventative*Maintenance*and*Safety*of*Fetal*Doppler****Featured*in*this*Section:*****Cooper,&Justin&and&Alex&Dahinten&for&EWH.&“Fetal&Monitor&Preventative&Maintenance.”&From&the&publication:&&Medical'Equipment'Troubleshooting'Flowchart'Handbook.&Durham,&NC:&Engineering&World&Health,&2013.& ** ** *




EQUIPMENT))Fetal)Doppler)Preventative)Maintenance))
Preventive(Maintenance((Fetal&Doppler/Monitor&Preventative&Maintenance&1. Clean&the&probe&before&every&use&to&disinfect.&2. Clean&the&probe&and&cable&after&every&use&with&a&damp&cloth&to&remove&gel.&&3. Check&the&batteries&periodically&to&ensure&no&corrosion&and&proper&charge.&&Fetal&Doppler&Proper&usage&guidelines&1. Remove&the&battery&if&not&in&use&for&an&extended&period.&2. When&cleaning&the&probe&prior&to&use,&use&a&sort&nonFabrasive&cloth&or&disposable&wipe&soaked&in&disinfectant.&Avoid&aerosol&disinfectants&or&solutions&containing&organic&solvents&or&alcohol.&Then&wipe&the&probe&with&a&nonFabrasive&cloth&soaked&in&water.&Finally&dry&the&probe&and&package&in&a&clean&bag,&covered&tray&or&other&way&or&careful&storage&and&transport.&3. To&sterilize&the&Fetal&Doppler&or&probes,&use&cold&gas&sterilization&such&as&ethylene&oxide&at&less&than&140&⁰F&or&the&Sterad&System.&4. Store&at&a&temperature&between&F10⁰C&and&60⁰C&with&a&humidity&of&between&15&and&90%.&Printer&Usage&


• For&Thermal&Paper&(must&use&company&provided&paper)&o Thermal&side&facing&up&o Make&sure&plastic&cover&and&sticky&tab&are&removed&o Printer&door&must&be&closed&correctly&o 30F240&BPM&(USA)&scale&or&50F210&BPM&scale&(foreign)&&&




*4.*Troubleshooting*and*Repair*of*Fetal*Monitors*****Featured*in*this*Section:****Cooper,&Justin&and&Alex&Dahinten&for&EWH.&“Fetal&Monitor&Troubleshooting&Flowchart.”&From&the&publication:&Medical'Equipment'Troubleshooting'Flowchart'Handbook.&Durham,&NC:&Engineering&World&Health,&2013.&& *** *




Fetal&Doppler&Repair&and&Troubleshooting&Flowchart* !* *




Description*& Textbox! Explanation!1! !Begin!Fetal!Doppler!Flow!Chart! Begin!diagnostic!process!for!a!work!order!on!Fetal!Doppler!2! !Does!it!turn!on?! Does!it!turn!on?!
3! Trouble!shoot!Power!Supply! See!Flowchart!on!Power!Supply,!and!BTA!skills!on!Power!Supply.!4! Does!the!screen!turn!on?! Does!the!screen!turn!on?!
5! Check!circuit!components! Troubleshoot!the!electrical!components.!See!BTA!skills!on!Electrical!Simple.!6! Does!the!speaker!work?! Is!sound!audible?!
7! Check!speaker/!circuit!components! Troubleshoot!the!electrical!components.!See!BTA!skills!on!Electrical!Simple.!8! Is!it!measuring!a!signal?! Is!the!monitor/Doppler!producing!HR!sound?!9! Check!if!probe!is!connected! Check!if!the!probe!is!connected!to!the!fetal!doppler/monitor.!
10! !Connect!the!probe! Connect!the!probe.!See!BTA!skills!on!Mechanical!–!Attachments.!11! !Check!if!probe!is!clean! Clean!the!probe.!See!BTA!skills!on!Cleaning.!
12! !Check!internal!circuitry,! Troubleshoot!the!electrical!components.!See!BTA!skills!on!Electrical!Simple.!13! !Check!if!you!need!more!gel! Apply!ultrasound!gel!to!the!probe.!14! !Is!the!heart!rate!in!a!normal!range?! Is!the!heart!rate!in!a!normal!range?!
15! !Check!circuitry!and!check!gel! Troubleshoot!the!electrical!components!and!apply!ultrasound!gel!to!the!probe!as!necessary.!See!BTA!skills!on!Electrical!Simple.!16! !Does!the!printer!print?! Is!there!a!marking!on!the!paper?!17! !Is!the!correct!paper!in>! Do!you!have!the!proper!thermal!paper?! !18! !Check!paper! Check!to!see!whether!paper!is!full.! !
19! !Is!it!calibrated?! Is!the!proper!Heart!Rate,!timing,!and!contraction!output?!Is!the!proper!calibration!signal!upon!start?!20! !Close!printer!door! Close!door.!




21! !Does!the!needle!work?! Does!the!needle!work?!22! !Clean!or!replace!needle! Clean!or!replace!needle.!See!BTA!skills!on!Mechanical.!23! !Does!the!motor!run?! Does!the!motor!rotate?!24! !Check!motor! See!motor!guide!and!BTA!skills!on!Motors.!
25! !Does!the!roller!work?! Does!the!roller!move!the!paper!at!the!correct!rate!without!slipping?!Are!there!cracks!or!damage!to!the!roller?!Is!the!roller!hard!and!showing!signs!of!age?!26! !Fix!or!replace!Roller! Fix!or!replace!Roller.!27! !Go!to!begin.! Go!to!begin.!
28! !Is!the!machine!reading!the!contractions?! Does!the!machine!show!numbers!for!the!uterine!contractions?!
29! !Is!the!belt!fastened?! Is!the!belt!fastened?!
30! !Fasten!belt.! Fasten!belt.!
31! !Go!to!begin.! Go!to!begin.!
32! !Does!the!signal!make!sense?! Does!the!uterine!contraction!signal!correlate!with!the!contractions!the!mother!is!having?!
33! !Does!the!machine!give!the!appropriate!metrics?! Does!the!machine!output!sensible!numbers!for!contraction!force!and!frequency?!
34! !Check!the!circuitry.! Troubleshoot!the!electrical!components.!See!BTA!skills!on!Electrical!Simple.!
35! !Is!the!belt!connected?! Is!the!belt!connected!to!the!fetal!monitor?!
36! !Connect!the!belt.! Connect!the!belt.!
37! !Does!the!tachometer!record!force?! Does!the!tachometer!record!force!numbers?!




38! !Replace!or!check!circuitry.! Replace!the!contraction!belt!or!troubleshoot!the!circuit!(see!troubleshooting!guide)!39! !End! End!the!flow!chart.!
40! !Go!to!begin.! Go!to!begin.!
41! !Go!to!begin.! Go!to!begin.!!




****SECTION*B:*Fetal*Doppler*** *




** 5.*Operation*and*Use*of*Fetal*Doppler****Featured*in*this*Section:***& Malkin,&Robert.&“Fetal&Monitor&and&Fetal&Doppler:&Use&and&Operation.”&From&the&publication:&&Medical'Instrumentation'in'the'Developing'World.&Engineering&World&Health,&2006.&&& WHO.&“Fetal&Heart&Detector,&Ultrasonic.”&From&the&publication:&Core'Medical'Equipment.&Geneva,&Switzerland,&2011.& ** Wikipedia.&“Doppler&Effect.”&Wikipedia,'p.'1K8.&Retrieved&from:&&https://en.wikipedia.org/wiki/Doppler_effect&*&* ** *




http://www.who.int/medical_devices/en/index.html
© Copyright ECRI Institute 2011 (not including the GMDN code and device name).


Reproduced with Permission from ECRI Institute’s Healthcare Product Comparison System.


© Copyright GMDN Agency 2011. GMDN codes and device names are reproduced with permission from the GMDN Agency.


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Ultrasonic fetal heart detectors are low-cost devices used in
a variety of healthcare settings to provide audible and visual
information about the fetus. The unit provides quick reassurance
of fetal well-being to both the mother and the healthcare worker.
Fetal heart detectors can easily detect fetal heart sounds
throughout the pregnancy, starting as early as 8 weeks. The
ability of most units to accurately calculate the fetal heart rate
has also made these devices valuable diagnostic tools.


Product description
Fetal heart detectors are devices that use ultrasonic waves to
provide audible and/or visual information. They consist of an
ultrasound-frequency electrical generator and appropriate
ultrasound transducers housed in a probe that is placed on
the maternal abdomen. Ultrasonic heartbeat detectors amplify
the audible frequency shift signal of the returned ultrasonic
waves and deliver it to speakers or headphones; the heart rate
is determined either by measuring the timing of the peaks in
the Doppler signal or, more accurately, by using automated
autocorrelation procedures. These devices can detect fetal heart
activity as soon as 10 weeks after conception. Advanced units
can even detect bidirectional blood fl ow, allowing the clinician
to evaluate maternal vessels, such as the uterine artery.


Principles of operation
Fetal heart detectors transmit high-frequency sound waves
either continuously or in pulses. In continuous-wave (CW)
units, a crystal vibrates as an electrical current passes through
it, creating and transmitting acoustic energy, while a second
crystal detects echoes from structures in the body. In pulsed-
Doppler systems, a single crystal alternately transmits periodic
bursts of ultrasonic waves and senses the echoed energy. In both
systems, the refl ected wave is reconverted to an electrical signal
that can be used to create an audible sound or a waveform.
Ultrasonic heartbeat detectors amplify the audible frequency
shift signal of the returned ultrasonic waves and deliver it to
speakers or headphones; the heart rate is determined either by
measuring the timing of the peaks in the Doppler signal or by
using automated autocorrelation procedures.


Operating steps
An acoustic coupling gel is spread over the skin to facilitate the
effi cient transmission of ultrasound waves into and out of the
body. The probe is placed against the mother’s abdomen. If the
scanned structures are in motion, the frequency of the returning
sound waves changes in proportion to the velocity and direction
of the moving structures. Fetal heart detectors amplify this
audible frequency change, known as Doppler shift, and channel
it to speakers or headphones.


Reported problems
Although researchers have yet to establish
whether a signifi cant risk exists, there is some
concern about whether exposure to ultrasonic
energy during diagnostic procedures is safe.
Many factors can affect the ability of the unit
to detect the fetal heartbeat (i.e., body fat and
blood fl ow can absorb acoustic energy). Since
pathogens may be present on the patient’s
skin, transmission of these organisms to the
transducer head commonly occurs.


Use and maintenance
User(s): Physicians, obstetric nurses,
community midwives


Maintenance: Biomedical or clinical engineer/
technician, medical staff, manufacturer/servicer


Training: Initial training by manufacturer,
operator’s manuals, user’s guide


Environment of use
Settings of use: Obstetrics (hospital, OB/GYN
practices), emergency medicine


Requirements: Battery, uninterruptible power
source (recharge batteries), appropriate
transducer with gel


Product specifi cations
Approx. dimensions (mm): 100 x 150 x 200
Approx. weight (kg): 1
Consumables: Batteries, gel
Price range (USD): 350 - 800
Typical product life time (years): 8
Shelf life (consumables): NA


Types and variations
Portable, handheld, tabletop units


Fetal Heart Detector, Ultrasonic
UMDNS GMDN
11696 Detectors, Fetal Heart, Ultrasonic 35068 Foetal heart detector, ultrasonic


Other common names:
Ultrasonic stethoscopes; fetal Dopplers; Monitor, heart rate, fetal ultrasonic; Monitor, heart sound, fetal, ultrasonic;
monitor, hemic sound, ultrasonic.




&QRRNGT GាGEV


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%PQQMFS FઢFDU PG XBUFS તPX BSPVOE B TXBO


6JG Doppler effect QT Doppler shift KU VJG EJCPIG
KP HTGSWGPE[ QH C YCXG QT QVJGT RGTKQFKE GXGPV HQT CP
QDUGTXGT OQXKPI TGNCVKXG VQ KVU UQWTEG +V KU PCOGF CHVGT
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TGEGFGU HTQO CP QDUGTXGT %QORCTGF VQ VJG GOKVVGF HTG
SWGPE[ VJG TGEGKXGF HTGSWGPE[ KU JKIJGT FWTKPI VJG CR
RTQCEJ KFGPVKECN CV VJG KPUVCPV QH RCUUKPI D[ CPF NQYGT
FWTKPI VJG TGEGUUKQP
9JGP VJG UQWTEG QH VJG YCXGU KU OQXKPI VQYCTF VJG QD
UGTXGT GCEJ UWEEGUUKXG YCXG ETGUV KU GOKVVGF HTQO C RQUK
VKQP ENQUGT VQ VJG QDUGTXGT VJCP VJG RTGXKQWU YCXG 6JGTG
HQTG GCEJ YCXG VCMGU UNKIJVN[ NGUU VKOG VQ TGCEJ VJG QD
UGTXGT VJCP VJG RTGXKQWU YCXG *GPEG VJG VKOG DGVYGGP


VJG CTTKXCN QH UWEEGUUKXG YCXG ETGUVU CV VJG QDUGTXGT KU
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HTQPVU KU TGFWEGF UQ VJG YCXGU ནDWPEJ VQIGVJGTཔ %QP
XGTUGN[ KH VJG UQWTEG QH YCXGU KU OQXKPI CYC[ HTQO VJG
QDUGTXGT GCEJ YCXG KU GOKVVGF HTQO C RQUKVKQP HCTVJGT
HTQO VJG QDUGTXGT VJCP VJG RTGXKQWU YCXG UQ VJG CTTKXCN
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TGNCVKXG VQ VJG OGFKWO KP YJKEJ VJG YCXGU CTG VTCPUOKV
VGF 6JG VQVCN &QRRNGT GាGEV OC[ VJGTGHQTG TGUWNV HTQO
OQVKQP QH VJG UQWTEG OQVKQP QH VJG QDUGTXGT QT OQVKQP
QH VJG OGFKWO 'CEJ QH VJGUG GាGEVU KU CPCN[\GF UGRC
TCVGN[ (QT YCXGU YJKEJ FQ PQV TGSWKTG C OGFKWO UWEJ CU
NKIJV QT ITCXKV[ KP IGPGTCN TGNCVKXKV[ QPN[ VJG TGNCVKXG FKH
HGTGPEG KP XGNQEKV[ DGVYGGP VJG QDUGTXGT CPF VJG UQWTEG
PGGFU VQ DG EQPUKFGTGF


1 Developments


&QRRNGT ិTUV RTQRQUGF VJKU GាGEV KP KP JKU VTGCVKUG
œCFS EBT GBSCJHF -JDIU EFS %PQQFMTUFSOF VOE FJOJHFS BO
EFSFS (FTUJSOF EFT )JNNFMT 1P VJG EQNQWTGF NKIJV QH
VJG DKPCT[ UVCTU CPF UQOG QVJGT UVCTU QH VJG JGCXGPU=?
6JG J[RQVJGUKU YCU VGUVGF HQT UQWPF YCXGU D[ $W[U $CN
NQV KP =? *G EQPិTOGF VJCV VJG UQWPFཐU RKVEJ YCU
JKIJGT VJCP VJG GOKVVGF HTGSWGPE[ YJGP VJG UQWPF UQWTEG
CRRTQCEJGF JKO CPF NQYGT VJCP VJG GOKVVGF HTGSWGPE[
YJGP VJG UQWPF UQWTEG TGEGFGF HTQO JKO *KRRQN[VG
(K\GCW FKUEQXGTGF KPFGRGPFGPVN[ VJG UCOG RJGPQOGPQP
QP GNGEVTQOCIPGVKE YCXGU KP KP (TCPEG VJG GH
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2 General


+P ENCUUKECN RJ[UKEU YJGTG VJG URGGFU QH UQWTEG CPF VJG
TGEGKXGT TGNCVKXG VQ VJG OGFKWO CTG NQYGT VJCP VJG XG
NQEKV[ QH YCXGU KP VJG OGFKWO VJG TGNCVKQPUJKR DGVYGGP
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VJG QVJGT
6JG CDQXG HQTOWNC CUUWOGU VJCV VJG UQWTEG KU GKVJGT FK
TGEVN[ CRRTQCEJKPI QT TGEGFKPI HTQO VJG QDUGTXGT +H
VJG UQWTEG CRRTQCEJGU VJG QDUGTXGT CV CP CPING DWV UVKNN
YKVJ C EQPUVCPV XGNQEKV[ VJG QDUGTXGF HTGSWGPE[ VJCV KU
ិTUV JGCTF KU JKIJGT VJCP VJG QDLGEVཐU GOKVVGF HTGSWGPE[
6JGTGCHVGT VJGTG KU C OQPQVQPKE FGETGCUG KP VJG QDUGTXGF
HTGSWGPE[ CU KV IGVU ENQUGT VQ VJG QDUGTXGT VJTQWIJ GSWCN
KV[ YJGP KV KU EQOKPI HTQO C FKTGEVKQP RGTRGPFKEWNCT VQ
VJG TGNCVKXGOQVKQP CPFYCU GOKVVGF CV VJG RQKPV QH ENQUGUV
CRRTQCEJ DWV YJGP VJG YCXG KU TGEGKXGF VJG UQWTEG CPF
QDUGTXGT YKNN PQ NQPIGT DG CV VJGKT ENQUGUV CPF C EQPVKP
WGF OQPQVQPKE FGETGCUG CU KV TGEGFGU HTQO VJG QDUGTXGT
9JGP VJG QDUGTXGT KU XGT[ ENQUG VQ VJG RCVJ QH VJG QDLGEV
VJG VTCPUKVKQP HTQO JKIJ VQ NQY HTGSWGPE[ KU XGT[ CDTWRV
9JGP VJG QDUGTXGT KU HCT HTQO VJG RCVJ QH VJG QDLGEV VJG
VTCPUKVKQP HTQO JKIJ VQ NQY HTGSWGPE[ KU ITCFWCN
+H VJG URGGFU v U CPF v T CTG UOCNN EQORCTGF VQ VJG URGGF
QH VJG YCXG VJG TGNCVKQPUJKR DGVYGGP QDUGTXGF HTGSWGPE[
f CPF GOKVVGF HTGSWGPE[ f KU CRRTQZKOCVGN[=?


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3 Analysis


6Q WPFGTUVCPF YJCV JCRRGPU EQPUKFGT VJG HQNNQYKPI CPCN
QI[ 5QOGQPG VJTQYU QPG DCNN GXGT[ UGEQPF CV C OCP
#UUWOG VJCV DCNNU VTCXGN YKVJ EQPUVCPV XGNQEKV[ +H VJG


VJTQYGT KU UVCVKQPCT[ VJG OCP YKNN TGEGKXG QPG DCNN GX
GT[ UGEQPF *QYGXGT KH VJG VJTQYGT KU OQXKPI VQYCTFU
VJG OCP JG YKNN TGEGKXG DCNNU OQTG HTGSWGPVN[ DGECWUG
VJG DCNNU YKNN DG NGUU URCEGF QWV 6JG KPXGTUG KU VTWG KH VJG
VJTQYGT KU OQXKPI CYC[ HTQO VJG OCP 5Q KV KU CEVWCNN[
VJG XBWFMFOHUI YJKEJ KU CាGEVGF CU C EQPUGSWGPEG VJG
TGEGKXGF HTGSWGPE[ KU CNUQ CាGEVGF +V OC[ CNUQ DG UCKF
VJCV VJG XGNQEKV[ QH VJG YCXG TGOCKPU EQPUVCPV YJGTGCU
YCXGNGPIVJ EJCPIGU JGPEG HTGSWGPE[ CNUQ EJCPIGU
9KVJ CP QDUGTXGT UVCVKQPCT[ TGNCVKXG VQ VJG OGFKWO KH C
OQXKPI UQWTEG KU GOKVVKPI YCXGU YKVJ CP CEVWCN HTGSWGPE[
f KP VJKU ECUG VJG YCXGNGPIVJ KU EJCPIGF VJG VTCPUOKU
UKQP XGNQEKV[ QH VJG YCXG MGGRU EQPUVCPV PQVG VJCV VJG
USBOTNJTTJPO WFMPDJUZ QH VJG YCXG FQGU PQV FGRGPF QP VJG
WFMPDJUZ PG UIF TPVSDF VJGP VJG QDUGTXGT FGVGEVU YCXGU
YKVJ C HTGSWGPE[ f IKXGP D[


f =
(


c
c + v U


)
f0


# UKOKNCT CPCN[UKU HQT C OQXKPI PCTFSWFS CPF C UVCVKQPCT[
UQWTEG KP VJKU ECUG VJG YCXGNGPIVJ MGGRU EQPUVCPV DWV
FWG VQ VJG OQVKQP VJG TCVG CV YJKEJ VJG QDUGTXGT TGEGKXGU
YCXGU CPF JGPEG VJG USBOTNJTTJPO WFMPDJUZ QH VJG YCXG
=YKVJ TGURGEV VQ VJG QDUGTXGT? KU EJCPIGF [KGNFU VJG
QDUGTXGF HTGSWGPE[


f =
(


c + v T
c


)
f0


6JGUG ECP DG IGPGTCNK\GF KPVQ VJG GSWCVKQP VJCV YCU RTG
UGPVGF KP VJG RTGXKQWU UGEVKQP


f =
(


c + v T
c + v U


)
f0


#P KPVGTGUVKPI GាGEV YCU RTGFKEVGF D[ .QTF 4C[NGKIJ KP
JKU ENCUUKE DQQM QP UQWPF KH VJG UQWTEG KU OQXKPI CV
VYKEG VJG URGGF QH UQWPF C OWUKECN RKGEG GOKVVGF D[ VJCV
UQWTEG YQWNF DG JGCTF KP EQTTGEV VKOG CPF VWPG DWV CBDL
XBSET=? 6JG &QRRNGT GាGEV YKVJ UQWPF KU QPN[ ENGCTN[
JGCTF YKVJ QDLGEVU OQXKPI CV JKIJ URGGF CU EJCPIG KP HTG
SWGPE[ QH OWUKECN VQPG KPXQNXGU C URGGF QH CTQWPF OG
VGTU RGT UGEQPF CPF UOCNNGT EJCPIGU KP HTGSWGPE[ ECP GCU
KN[ DG EQPHWUGF D[ EJCPIGU KP VJG CORNKVWFG QH VJG UQWPFU
HTQO OQXKPI GOKVVGTU 0GKN # &QYPKG JCU FGOQPUVTCVGF
=?JQY VJG &QRRNGT GាGEV ECP DG OCFG OWEJ OQTG GCUKN[
CWFKDNG D[ WUKPI CP WNVTCUQPKE GI M*\ GOKVVGT QP VJG
OQXKPI QDLGEV 6JG QDUGTXGT VJGP WUGU C JGVGTQF[PG HTG
SWGPE[ EQPXGTVGT CU WUGF KP OCP[ DCV FGVGEVQTU VQ NKUVGP
VQ C DCPF CTQWPF M*\ +P VJKU ECUG YKVJ VJG DCV FG
VGEVQT VWPGF VQ IKXG HTGSWGPE[ HQT VJG UVCVKQPCT[ GOKVVGT
QH *\ VJG QDUGTXGT YKNN RGTEGKXG C HTGSWGPE[ UJKHV
QH C YJQNG VQPG *\ KH VJG GOKVVGT VTCXGNU CV OGVGTU
RGT UGEQPF




"11-*$"5*0/


9QTNF 9CT ++ TGNKGU WRQP &QRRNGT TCFCT VQ FGVQPCVG GZ
RNQUKXGU CV VJG EQTTGEV VKOG JGKIJV FKUVCPEG GVE
$GECWUG VJG FQRRNGT UJKHV CាGEVU VJG YCXG KPEKFGPV WRQP
VJG VCTIGV CU YGNN CU VJG YCXG TGីGEVGF DCEM VQ VJG TCFCT
VJG EJCPIG KP HTGSWGPE[ QDUGTXGF D[ C TCFCT FWG VQ C VCT
IGV OQXKPI CV TGNCVKXG XGNQEKV[ ∆ v KU VYKEG VJCV HTQO VJG
UCOG VCTIGV GOKVVKPI C YCXG


∆f = 2 ∆vc f0 =?


4.4 Medical imaging and blood flow mea-
surement


/CKP CTVKENG /GFKECNAWNVTCUQPQITCRJ[ h
&QRRNGTAWNVTCUQPQITCRJ[
#P GEJQECTFKQITCO ECP YKVJKP EGTVCKP NKOKVU RTQFWEG


$PMPVS તPX VMUSBTPOPHSBQIZ %PQQMFS PG B DBSPUJE BSUFSZ
TDBOOFS BOE TDSFFO


CP CEEWTCVG CUUGUUOGPV QH VJG FKTGEVKQP QH DNQQF ីQY CPF
VJG XGNQEKV[ QH DNQQF CPF ECTFKCE VKUUWG CV CP[ CTDKVTCT[
RQKPV WUKPI VJG &QRRNGT GាGEV 1PG QH VJG NKOKVCVKQPU
KU VJCV VJG WNVTCUQWPF DGCO UJQWNF DG CU RCTCNNGN VQ VJG
DNQQF ីQY CU RQUUKDNG 8GNQEKV[ OGCUWTGOGPVU CNNQY
CUUGUUOGPV QH ECTFKCE XCNXG CTGCU CPF HWPEVKQP CP[
CDPQTOCN EQOOWPKECVKQPU DGVYGGP VJG NGHV CPF TKIJV
UKFG QH VJG JGCTV CP[ NGCMKPI QH DNQQF VJTQWIJ VJG XCNXGU


XCNXWNCT TGIWTIKVCVKQP CPF ECNEWNCVKQP QH VJG ECTFKCE
QWVRWV %QPVTCUVGPJCPEGF WNVTCUQWPF WUKPI ICUិNNGF
OKETQDWDDNG EQPVTCUV OGFKC ECP DG WUGF VQ KORTQXG
XGNQEKV[ QT QVJGT ីQYTGNCVGF OGFKECN OGCUWTGOGPVU
#NVJQWIJ ན&QRRNGTཔ JCU DGEQOG U[PQP[OQWU YKVJ ནXG
NQEKV[ OGCUWTGOGPVཔ KP OGFKECN KOCIKPI KP OCP[ ECUGU
KV KU PQV VJG HTGSWGPE[ UJKHV &QRRNGT UJKHV QH VJG TGEGKXGF
UKIPCN VJCV KU OGCUWTGF DWV VJG RJCUG UJKHV XIFO VJG TG
EGKXGF UKIPCN CTTKXGU
8GNQEKV[ OGCUWTGOGPVU QH DNQQF ីQY CTG CNUQ WUGF KP
QVJGT ិGNFU QH OGFKECN WNVTCUQPQITCRJ[ UWEJ CU QDUVGVTKE
WNVTCUQPQITCRJ[ CPF PGWTQNQI[ 8GNQEKV[ OGCUWTGOGPV
QH DNQQF ីQY KP CTVGTKGU CPF XGKPU DCUGF QP &QRRNGT GH
HGEV KU CP GាGEVKXG VQQN HQT FKCIPQUKU QH XCUEWNCT RTQDNGOU
NKMG UVGPQUKU=?


4.5 Flow measurement


+PUVTWOGPVU UWEJ CU VJG NCUGT &QRRNGT XGNQEKOGVGT
.&8 CPF CEQWUVKE &QRRNGT XGNQEKOGVGT #&8 JCXG
DGGP FGXGNQRGF VQ OGCUWTG XGNQEKVKGU KP C ីWKF ីQY 6JG
.&8 GOKVU C NKIJV DGCO CPF VJG #&8 GOKVU CP WNVTCUQPKE
CEQWUVKE DWTUV CPF OGCUWTG VJG &QRRNGT UJKHV KP YCXG
NGPIVJU QH TGីGEVKQPU HTQO RCTVKENGU OQXKPI YKVJ VJG ីQY
6JG CEVWCN ីQY KU EQORWVGF CU C HWPEVKQP QH VJG YCVGT
XGNQEKV[ CPF RJCUG 6JKU VGEJPKSWG CNNQYU PQPKPVTWUKXG
ីQY OGCUWTGOGPVU CV JKIJ RTGEKUKQP CPF JKIJ HTGSWGPE[


4.6 Velocity profile measurement


&GXGNQRGF QTKIKPCNN[ HQT XGNQEKV[ OGCUWTGOGPVU KP OGF
KECN CRRNKECVKQPU DNQQF ីQY 7NVTCUQPKE &QRRNGT 8G
NQEKOGVT[ 7&8 ECP OGCUWTG KP TGCN VKOG EQORNGVG XG
NQEKV[ RTQិNG KP CNOQUV CP[ NKSWKFU EQPVCKPKPI RCTVKENGU KP
UWURGPUKQP UWEJ CU FWUV ICU DWDDNGU GOWNUKQPU (NQYU
ECP DG RWNUCVKPI QUEKNNCVKPI NCOKPCT QT VWTDWNGPV UVCVKQP
CT[ QT VTCPUKGPV 6JKU VGEJPKSWG KU HWNN[ PQPKPXCUKXG


4.7 Satellite communication


(CUV OQXKPI UCVGNNKVGU ECP JCXG C &QRRNGT UJKHV QH FQ\GPU
QH MKNQJGTV\ TGNCVKXG VQ C ITQWPF UVCVKQP 6JG URGGF VJWU
OCIPKVWFG QH &QRRNGT GាGEV EJCPIGU FWG VQ GCTVJ EWT
XCVWTG &[PCOKE &QRRNGT EQORGPUCVKQP YJGTG VJG HTG
SWGPE[ QH C UKIPCN KU EJCPIGF OWNVKRNG VKOGU FWTKPI VTCPU
OKUUKQP KU WUGF UQ VJG UCVGNNKVG TGEGKXGU C EQPUVCPV HTG
SWGPE[ UKIPCN=?


4.8 Audio


6JG .GUNKG URGCMGT CUUQEKCVGF YKVJ CPF RTGFQOKPCPVN[
WUGF YKVJ VJG *COOQPF $ QTICP VCMGU CFXCPVCIG QH
VJG &QRRNGT 'ាGEV D[ WUKPI CP GNGEVTKE OQVQT VQ TQVCVG CP
CEQWUVKE JQTP CTQWPF C NQWFURGCMGT UGPFKPI KVU UQWPF KP




C EKTENG 6JKU TGUWNVU CV VJG NKUVGPGTཐU GCT KP TCRKFN[ ីWEVW
CVKPI HTGSWGPEKGU QH C MG[DQCTF PQVG


4.9 Vibration measurement


# NCUGT &QRRNGT XKDTQOGVGT .&8 KU C PQPEQPVCEV
OGVJQF HQT OGCUWTKPI XKDTCVKQP 6JG NCUGT DGCO HTQO
VJG .&8 KU FKTGEVGF CV VJG UWTHCEG QH KPVGTGUV CPF VJG XK
DTCVKQP CORNKVWFG CPF HTGSWGPE[ CTG GZVTCEVGF HTQO VJG
&QRRNGT UJKHV QH VJG NCUGT DGCO HTGSWGPE[ FWG VQ VJG OQ
VKQP QH VJG UWTHCEG


5 Inverse Doppler effect


5KPEG UEKGPVKUVU UWEJ CU 8KEVQT 8GUGNCIQ JCXG URGE
WNCVGF CDQWV VJG RQUUKDKNKV[ QH CP +PXGTUG &QRRNGT GាGEV
#P GZRGTKOGPV VJCV ENCKOGF VQ JCXG FGVGEVGF VJKU GាGEV
YCU EQPFWEVGF D[ 0KIGN 5GFFQP CPF 6TGXQT $GCTRCTM KP
$TKUVQN 7PKVGF -KPIFQO KP =?


4GUGCTEJGTU HTQO 5YKPDWTPG 7PKXGTUKV[ QH 6GEJPQNQI[
CPF VJG 7PKXGTUKV[ QH 5JCPIJCK HQT 5EKGPEG CPF 6GEJPQN
QI[ UJQYGF VJCV VJKU GាGEV ECP DG QDUGTXGF KP QRVKECN
HTGSWGPEKGU CU YGNN 6JKU YCU OCFG RQUUKDNG D[ ITQYKPI
C RJQVQPKE ET[UVCN CPF RTQLGEVKPI C NCUGT DGCO KPVQ VJG
ET[UVCN 6JKU OCFG VJG ET[UVCN CEV NKMG C UWRGT RTKUO CPF
VJG +PXGTUG &QRRNGT 'ាGEV EQWNF DG QDUGTXGF=?


6 See also


• 4GNCVKXKUVKE &QRRNGT GាGEV


• &QRRNGTITCRJ


• &QRRNGT EQQNKPI


• (K\GCW GZRGTKOGPV


• (CFKPI


• 2JQVQCEQWUVKE &QRRNGT GាGEV


• &KាGTGPVKCN &QRRNGT GាGEV


• 4C[NGKIJ HCFKPI


• 4GFUJKHV


7 References


=? #NGE 'FGP 5IF TFBSDI GPS $ISJTUJBO %PQQMFS5RTKPIGT
8GTNCI 9KGP %QPVCKPU C HCEUKOKNG GFKVKQP YKVJ CP
'PINKUJ VTCPUNCVKQP


=? $W[U $CNNQV ན#MWUVKUEJG 8GTUWEJG CWH FGT
0KGFGTN¥PFKUEJGP 'KUGPDCJP PGDUV IGNGIGPVNKEJGP
$GOGTMWPIGP \WT 6JGQTKG FGU *TP 2TQH &QRRNGT


KP )GTOCP "OOBMFO EFS 1IZTJL VOE $IFNJF
11 ཊ $KDEQFG#P2$
FQKCPFR


=? (K\GCW ན#EQWUVKSWG GV QRVKSWGཔ -FDUVSF 4PDJ©U© 1IJMP
NBUIJRVF EF 1BSJT &GEGODGT #EEQTFKPI VQ
$GEMGT RI VJKU YCU PGXGT RWDNKUJGF DWV TGEQWPVGF
D[ / /QKIPQ ན4ªRGTVQKTG FQRVKSWG OQFGTPGཔ
KP (TGPEJ XQN RR CPF NCVGT KP HWNN D[
(K\GCW ན&GU GាGVU FW OQWXGOGPV UWT NG VQP FGU XKDTC
VKQPU UQPQTGU GV UWT NC NQPIGWT FQPFG FGU TC[QPU FG NW
OK©TG =2CTKU ? "OOBMFT EF $IJNJF FU EF 1IZTJRVF


• $GEMGT $CTDCTC , $GEMGT 6OSBWFM
MJOH 4UBSMJHIU 8JMMJBN BOE .BSHBSFU )VHHJOT BOE
UIF 3JTF PG UIF /FX "TUSPOPNZ KNNWUVTCVGF 'FK
VKQP %CODTKFIG 7PKXGTUKV[ 2TGUU +5$0
:


=? 5EQVV 4WUUGNN ,QJP ན1P EGTVCKP GាGEVU RTQFWEGF
QP UQWPF D[ VJG TCRKF OQVKQP QH VJG QDUGTXGTཔ 3FQPSU
PG UIF &JHIUFFOUI .FFUJOH PG UIF #SJUJTI "TTPDJBUJPO GPS UIF
"EWBODFNFOU PG 4DJFODF ,QJP /WTTC[ .QPFQP KP
18 ཊ 4GVTKGXGF


=? 4QUGP ,QG )QVJCTF .KUC 3WKPP &ODZDMPQFEJB
PG 1IZTJDBM 4DJFODF +PHQDCUG 2WDNKUJKPI R +5$0
'ZVTCEV QH RCIG


=? 5VTWVV .QTF 4C[NGKIJ ,QJP 9KNNKCO /CE/KNNCP
%Q GF 5IF 5IFPSZ PG 4PVOE 2 GF R


=? &QYPKG 0GKN # 8CEWWO $C\QQMCU 'NGEVTKE 4CKPDQY
,GNN[ CPF QVJGT RTQLGEVU HQT 5CVWTFC[ 5EKGPEG 2TKPEG
VQP +5$P


=? 6JG FKUVKPEVKQP KU OCFG ENGCT KP *CTTKUQP 'FYCTF 4QDGTV
$PTNPMPHZ 5IF 4DJFODF PG UIF 6OJWFSTF PF GF
%CODTKFIG 7PKXGTUKV[ 2TGUU RR ઢ +5$0
:


=? JVVRYYYTCFCTVWVQTKCNGWEQJGTGPVEQGPJVON


=? 'XCPU & * /E&KEMGP 9 0 %PQQMFS 6MUSB
TPVOE PF GF 0GY ;QTM ,QJP 9KNG[ CPF 5QPU +5$0


=? 3KPIEJQPI .KW ན&QRRNGT OGCUWTGOGPV CPF EQO
RGPUCVKQP KP OQDKNG UCVGNNKVG EQOOWPKECVKQPU U[UVGOUཔ
.JMJUBSZ $PNNVOJDBUJPOT $POGFSFODF 1SPDFFEJOHT .*-
$0. 1 ཊ FQKOKNEQO


=? -Q\[TGX #NGZCPFGT $ XCP FGT9GKFG &CPKGN 9
ན'ZRNCPCVKQP QH VJG +PXGTUG &QRRNGT 'ាGEV 1DUGTXGF KP
0QPNKPGCT 6TCPUOKUUKQP .KPGUཔ 1IZTJDBM 3FWJFX -FU
UFST 94 $KDEQFG2J4X.V-
FQK2J[U4GX.GVV 2/+&
.C[ UWOOCT[ ཊ 1IZTPSH /C[


=? 4DJFOUJTUT SFWFSTF %PQQMFS &ઢFDU RJ[UQTIEQO /CTEJ
TGVTKGXGF




&95&3/"- -*/,4


8 Further reading


• &QRRNGT % œCFS EBT GBSCJHF -JDIU EFS
%PQQFMTUFSOF VOE FJOJHFS BOEFSFS (FTUJSOF EFT )JN
NFMT "CPVU UIF DPMPVSFE MJHIU PG UIF CJOBSZ TUBST BOE
TPNF PUIFS TUBST PG UIF IFBWFOT 2WDNKUJGT #D
JCPFNWPIGP FGT -·PKIN $·JO )GUGNNUEJCHV FGT
9KUUGPUEJCHVGP 8 (QNIG $F 5 =2TQ
EGGFKPIU QH VJG 4Q[CN $QJGOKCP 5QEKGV[ QH 5EKGPEGU
2CTV 8 8QN ? 2TCIWG 4GKUUWGF
5QOG UQWTEGU OGPVKQP CU [GCT QH RWDNKECVKQP
DGECWUG KP VJCV [GCT VJG CTVKENG YCU RWDNKUJGF KP VJG
2TQEGGFKPIU QH VJG $QJGOKCP 5QEKGV[ QH 5EKGPEGU
&QRRNGT JKOUGNH TGHGTTGF VQ VJG RWDNKECVKQP CU ན2TCI
DGK $QTTQUEJ WPF #PFTª DGECWUG KP JG
JCF C RTGNKOKPCT[ GFKVKQP RTKPVGF VJCV JG FKUVTKDWVGF
KPFGRGPFGPVN[


• ན&QRRNGT CPF VJG &QRRNGT GាGEVཔ ' 0 FC % #P
FTCFG &OEFBWPVS 8QN :8+++ 0Q ,CPWCT[
RWDNKUJGF D[ +%+ .QPFQP *KUVQTKECN CEEQWPV QH
&QRRNGTཐU QTKIKPCN RCRGT CPF UWDUGSWGPV FGXGNQR
OGPVU


• #FTKCP 'NGPK ,WPG ན&QRRNGT 'ាGEVཔ
0%5# 4GVTKGXGF


9 External links


• &QRRNGT 'ាGEV =5EKGPEG9QTNF?


• ,CXC UKOWNCVKQP QH &QRRNGT GាGEV


• &QRRNGT 5JKHV HQT 5QWPF CPF .KIJV CV /CVJ2CIGU


• (NCUJ UKOWNCVKQP CPF ICOG QH &QRRNGT GាGEV QH
UQWPF CV 5ETCVEJ RTQITCOOKPI NCPIWCIG


• 6JG &QRRNGT 'ាGEV CPF 5QPKE $QQOU &# 4WUUGNN
-GVVGTKPI 7PKXGTUKV[


• 8KFGQ /CUJWR YKVJ &QRRNGT 'ាGEV XKFGQU


• 9CXG 2TQRCICVKQP GSPN +PIO EF 1JMMJT #P CPKOCVKQP
UJQYKPI VJCV VJG URGGF QH COQXKPIYCXG UQWTEG FQGU
PQV CាGEV VJG URGGF QH VJG YCXG


• '/ 9CXG #PKOCVKQP GSPN +PIO EF 1JMMJT *QY CP
GNGEVTQOCIPGVKE YCXG RTQRCICVGU VJTQWIJ C XCEWWO


• &QRRNGT 5JKHV &GOQ +PVGTCEVKXG ីCUJ UKOWNCVKQP
HQT FGOQPUVTCVKPI &QRRNGT UJKHV


• +PVGTCEVKXG CRRNGVU CV 2J[UKEU




10 Text and image sources, contributors, and licenses


10.1 Text
• Doppler effect 4PVSDF JVVRUGPYKMKRGFKCQTIYKMK&QRRNGTAGHHGEV!QNFKF $POUSJCVUPST #ZGN$QNFV #R #PFTG 'PIGNU
:CQPQP &T$QD 5VGXGTVKIQ 2CVTKEM /KEJCGN *CTF[ #NCP 2GCMCNN #NិQ #JQGTUVGOGKGT <QG$ 9OOQTTQY ,WNGUF .NWNN #PFTGU 'X
GTECV 9KMKDQTI 5JCWP1H6JG.KXG #PFTGYOCP *[CEKPVJ ,PE (KDQPCEEK ,OCTVKPG\QV ,QTIG)) ,GាS %FCPI (TGFTKM <CPFRGTN
.QYGNNKCP 5XGTFTWR &*0 *CNKDWVV *CFCN 9KMKDQV ,GTT[(TKGFOCP %CTPKNFQ )KHVNKVG &QE9CVUQP &T URQTM *CTR 9QNHMGGRGT
$TCFGQU )TCRJQP %WTRU %CPVWU .GQPCTF ) &OOCWU 'XQNV 4CJ 7VEWTUEJ 8CPKUJGF WUGT UXKPGVLQIKHOYLHIQKVLQUHI $CTV 8GT
UKGEM #PVCPFTWU )WPPCT .CTUUQP /COK\QW 4FUOKVJ ,GTGO[MGOR &QWICNE +CPVTGUOCP 7TJKZKFWT ,Q[QWU #UMGYEJCP 7MGZRCV
(NGZ /KMG 4QUQHV %#.4 ,60 *CTWQ &KUEQURKPUVGT 2GPKUDTGCVJ 8UOKVJ 5RWPFWP /WTVCUC $GPFGT <CUNCX 4QDGTV 2 15JGC
9CVGT (KUJ 5RGCTJGCF 5KGVUG 5PGN 2GTHGEVQ $QDQ -GTQP %[UV .GQPCTFQ)TGIKCPKP 'XIGP[ 7PWUGF 5RCTMICR .C IQWVVG FG
RNWKG 0M 5EGPVQPK 1DTCFQXKE )QTCP 5CO -QTP 0UCC 'TWCPVCNQP #NCPUQJP -CTNVJGITGCV #TVJGPC 5OUMKF 'MMQ %QOTCFG
2#4 (CYEGVV $CTV 8GTM ;QUUKGC`GPYKMK %DWTPGVV &KTCE 2GVJT 4DKHCP )GPG 0[ICCTF &LUCUUQ 1NGI #NGZCPFTQX %COY
2QN 'UULC[ 2HCNUVCF 6GXCVTQP`GPYKMK 4PV &GNVCDGKIPGV /CTQU ;WTKM &RT )TCOOCTDQV 5CRGTCWF`GPYKMK 4LYKNOUK %GKP
VWTKQP ,KRJGZ 5CPIQ -GXOKVEJ .GKVJR (NC$QV &CDWGM 4GZ0. )WTEJ $OKEQOR -KPI QH *GCTVU %JQDQV &8FO ;WTKM$QV
9CXGNGPIVJ &CTM#XGPIGT %JTKU %CRQEEKC ,CDDGT9QM )CKWU %QTPGNKWU 5CNUD 0CYNKP9KMK 4QDGTVXCP 'TM&GOQP ,CZN +TKUJIW[
$TCPFQP /KMGDNCU 'ODV`GPYKMK &DិTU 5KNXGTJKNN 2JCGFTWU #NCTQD ,QUJ .GQPCTFQ4QDV :QTZ 5VCZTKPIQNF -WPIHWCFCO
6.5WFC &CTTGN HTCPEKU )TKP$QV`GPYKMK 0KRRQQ 5GNOQ &8& 4 9 &WF\EQO 5OCEM$QV (QECN2QKPV 2'*QYNCPF 5CTCXCUM 5ME[
1\QPG <GTQF'IQ %CPVJWUWU $K6 5GRVGITCO )Cា 5KGDTGP /CEKPVQUJ 7UGT )KNNKCO 1JPQKVULCOKG #VK -WT[MJ 4CLGGX
OCUU`GPYKMK 6JWORGTYCTF 5KNN[ TCDDKV 5EJិHV[6JTGG -TCNNLC /CZ5GO %CPV UNGGR ENQYP YKNN GCV OG *CTT[ 3 *COOGT 1TRJCP$QV
%Y[ ,QUJWC`GPYKMK #NFCTQP #SPIW[GP 5RGEVTQITCO *IKNDGTV $QIUCV -WMKPK .RYP 5TKMGKV .QQFQI 'XGP ,QJP9KVVNG
*XP 5VYCNMGTUVGT 1YNDWUVGT $CUOCPFWFG +CFKUVCT 2 %DWEMNG[ *QOG[ECV :KQPDQZ 2GLOCP +TKFGUEGPV #\ 6CYMGT
DQV %JGVXQTPQ ,(QTIGV 4QFPG[UOCNN $GGP#TQWPF#9JKNG 0KPGV[QPG )*G &IY 107PKEQTP ,QJPLQJPUVQP 6\CRJMKGN %CJM /%
5JCFYUVCNMT 9KMKRGFKCTWNGU 1FKG /KEJCGN % 2TKEG 1OKETQPRGTUGK 2KPM[ UN 6JKLUDQV 'RDT $KNN 0[G VJG YJGGNKP IW[
&GEQTKCP 0KNP HCP %CTTQV/CP *GCFDQOD 9KNNKCO* /CTGM 8GTVKWO ,COGU 6JNLEN 8CPKCE 'UECTDQV /GPVKិUVQ +CNUQC
ITGG #PVK8CPFCN$QV .WPC 5CPVKP 5GCRJQVQ ,HQUQTKQ 4KEQ 2GVGT *CTTKOCP .GWMQ /'4% #PFQPKE 1LEJCUG -KTTCIGU $GCWOQPV
/T ) 9KNNKCOU #ETQVGTKQP /CIKQNCFKVKU $QPIYCTTKQT 8Q#$QV ++ $CP4C[ 8QNQUJKPQX :CPVJ[O 6YUZ %QNKPUYGGV ,CាC%CMG.QXGT
2+TKUJ %LGOOQVV %KCEEQPC .V*KLC -H[HF /CTVKP$QV 56$QV 7NVTCXKQNGV UEKUUQT ីCOG 2DTQMU 9QNHRWR ,FGNCPQ[ /CPIG
)TCGOGGUOKVJ 0WODQ 2GVGT %JCUVCKP *CPU &WPMGNDGTI 7PENG &KEM )KPUGPIDQOD /CO[NGU $TQMGP5RJGTG /E5N[ ,GGRFC[ ,QP
/E.QQPG +PQO[CDEU #OETCYHQTF 2FEQQM 'CTPJCTFV %CTFKPCN&CP %5WOKV 2NGCUCPVXKNNG 5VTCPIGT%CXG&WEM 2JKNKR 6TWGOCP
6:K-K$Q6 6GGVGVQ`GPYKMK ,C[% 5KIGNJQDKV ,CEMHQTM 2U[EJG $QV-WPI 53. (CNEQP $CTVNGX 5GTGUKP 6JKUKUO[TQី 6JGJCO
OGT /QPV[ 2LQGH .QICP 5KG$QV ;KPVCP 0WOGPQTGCP (N[GT 4GDQTP 6KRVQGV[ 4CFQP 2TCVKM OCNN[C 1FC /CTK ,5RWPI
2QDRPWM 1Z[OQTQP #PVQPKQ .QRG\ 5LN %JCPUQPJ $GPQPK$QV`GPYKMK 1OPKKORQVGPV -GXKPDEQNNKPU /CTM/.N ,QPOVMKUEQ
6YKPUFC[ %NWG$QV $KPMUVGTPGV 6JG 6JKPI 6JCV 5JQWNF 0QV $G .#IWTN 4CHCGNICTEKC &CPKGN&GKDNGT %QWPVGT8CPFCNKUO$QV 2KNGFJKIJ
GTCPFFGGRGT 5QOPQ &TCIQP$QV 'ZEKTKCN 1VVTG 8CPKUJGFWUGT 2TKGVQSWKNOGU 6PZOCP 6JKPII *QPG[OCP #TKUVQUNC[GT
5QZ$QV +++ :.KPM$QV 4TGCICP 9KM*GCF 0GNNKG$N[ /CTEJKLG 4GVQQ #FFDQV 9KNNMKPI *CNQUGCP -WRQNQXGT ;QGPKV ,Q
LJWVVQP 1VKULKOO[ ,PETCVQP +TQPJQNFU #DQEVQM &QYPNQCF 7UGT&Ĕ )NCPG #PPC(TCPEG 65VGKP 6KFG TQNNU 5OCTV[GRR $GCVU
DQZ ,QJPEQNVQP .GIQDQV .WEMCUDQV ;QDQV & 2VDQVIQWTQW 4*$ 6*'0 9*1 9#5 2*10'! +9*) 04-7&5-
$CEMUNCUJ (QTYCTFUNCUJ #PQOKG$16 5CHFCTOCTYCV 'HC 6WEQZP 'VCP , 6CN 2KCPQ PQP VTQRRQ #FLWUV5JKHV ;CEJVUOCP $NCMGHTKIQ
/CPQMCTVJKMG[CPM /CVGTKCNUEKGPVKUV 4CV1OGVGT 2GCXG[ %KVCVKQP DQV 'WOQNRQ $WI :SDQV $NGPPQY 01TDGEM 2KUJCYDCD[
)TQWEJQ$QV ,JDFGN 5EKDGT&QE 2TWPGUSWCNGT 4KDQV$16 /CVJQPKWU #OCWT[ &QWNQU %JTKUVQU 4COUJGPICNG 5JCFQYLCOU #DC%CN
,QCSWKP 6JGJGNRHWNDQV $CLRG[GG .KSWKFNWEM .QQMCPI 6JG-KPI 2KPGVJKEMGV ,KXGG $NCW խնծչս 6QO4GFKPI 'NGXCPV 9KM
KVCPXKT /CIKEMCNNYK\ 0QQP\ 6QP[OCPI ,WLWVCEWNCT &CXKFEQP 2[PH (QZ$QV 6QDG$QV #MUJKV )Q[CN 4GCRGT 'VGTPCN /GCP CU
EWUVCTF /E5CMU 4LYKNOUK$QV 2K\EQ 0GTF[5EKGPEG&WFG 0GYV[ ,OKNGU 'OCWU$QV 1TRJCP 9KMK /QTGVKO +PEQIPKVQ
'TIQ5WO 4# (KPKEM[ ETQE 'FKVQTRGTUQP 9KMKRGNNK -MC 'TRGTV 6JGEJGGU[MKF *JJKRRQ *WPVGTU ,COGUTGKFCP *F
OKECDNG #ZZQPPិTG &QPPGT $KGIGNUGP .NKIJVGZ &#5*$QV#8 4GUGCTEJ4CXG )YGPEJCP %NWG$QV 0) %QEW$QV %JGUVGT /CTMGN
/KNNGTOM 7RVJGVTCKN #OQU DGP #XTCJCO (TKGVLGU (KPPKICPCYCMGPU /WQP *GNRHWN 2KZKG $QV 6KVQFWVVC $KDEQFG $QV 5Z[DWMUC $OW
UKEKCP (WTMJCQEGCP *CUJGO UHCTKO .CF[ICIC 6LDKTF ,CEMLCEM , *GTQZF\GTQ #V[JYG[ ࣓࣭ࣣࣩ &QPTGCEJ
2YPCIG 8NCUQXCF +PMYQP /CVGHMT 6JG +NNWUKXG /CP %JTKU)WCNVKGTK 6JKPMU RNCPGU 5CG *CTTDGCTJCTTDGCT &GZDQV 9GD
ENKGPV 0QRG,WUV#NGZ /CZTKIJVYKPI .WIKC (TQUV[ 4GCVNCU -CGTQ&QV )TGGPITGGPITGGPTGF 5QPKEDCO -KF# 5WTXKXCN
1DUGTXGT 5FCGWP 8KRKPXKPW &WUVKP 8 5 &CXKF.GKIJ'NNKU ,COKGDDDDD *K6JGTG %JKDSE /KMCGNW 3WCPVWO/CVV ,CUJIFL
ICM[C 2QGRMQR ,UJCTDGT ,2CTM .CWTGP)TCEG $NWGUVGGNOCIPWO -GNN[EJCW 6GVTC SWCTM 7P9GCXG 4QFQNHQJKFCNIQ
-CURCT$QV $-05 CPF #PQP[OQWU


10.2 Images
• File:CarotidDoppler1.jpg 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPU%CTQVKF&QRRNGTLRI -JDFOTF %% $;
$POUSJCVUPST 1YP YQTM 0SJHJOBM BSUJTU 'VCP , 6CN


• File:Commons-logo.svg 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCGPC%QOOQPUNQIQUXI -JDFOTF ! $POUSJCVUPST ! 0SJHJOBM
BSUJTU !


• File:Doppler_effect_diagrammatic.svg 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPUH&QRRNGTAGHHGEVA
FKCITCOOCVKEUXI -JDFOTF %%$;5# $POUSJCVUPST +OCIG&QRRNGT GាGEV FKCITCOOCVKERPI 0SJHJOBM BSUJTU 6MCTEJGT KORTQXGF D[
6CVQWVG


• File:Doppler_hattyu.jpg 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPU&QRRNGTAJCVV[WLRI -JDFOTF %% $;5#
$POUSJCVUPST 1YP YQTM 0SJHJOBM BSUJTU <¢VQP[K 5¢PFQT KHL (K\RGF


• File:Dopplereffectsourcemovingrightatmach0.7.gif 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPUEE
&QRRNGTGHHGEVUQWTEGOQXKPITKIJVCVOCEJIKH -JDFOTF %% $;5# $POUSJCVUPST 1YP YQTM 0SJHJOBM BSUJTU .QQMCPI OCP[
VJCPMU VQ (W-YWP *YCPI CPF CWVJQT QH 'CU[ ,CXC 5KOWNCVKQP (TCPEKUEQ 'USWGODTG




5&95 "/% *."(& 4063$&4 $0/53*#65034 "/% -*$&/4&4


• File:Dopplereffectsourcemovingrightatmach1.0.gif 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPUFF
&QRRNGTGHHGEVUQWTEGOQXKPITKIJVCVOCEJIKH -JDFOTF %% $;5# $POUSJCVUPST 1YP YQTM 0SJHJOBM BSUJTU .QQMCPI OCP[
VJCPMU VQ (W-YWP *YCPI CPF CWVJQT QH 'CU[ ,CXC 5KOWNCVKQP (TCPEKUEQ 'USWGODTG


• File:Dopplereffectsourcemovingrightatmach1.4.gif 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPUGG
&QRRNGTGHHGEVUQWTEGOQXKPITKIJVCVOCEJIKH -JDFOTF %% $;5# $POUSJCVUPST 1YP YQTM 0SJHJOBM BSUJTU .QQMCPI OCP[
VJCPMU VQ (W-YWP *YCPI CPF CWVJQT QH 'CU[ ,CXC 5KOWNCVKQP (TCPEKUEQ 'USWGODTG


• File:Dopplereffectstationary.gif 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPUGG&QRRNGTGHHGEVUVCVKQPCT[IKH -JDFOTF
%% $;5# $POUSJCVUPST 1YP YQTM 0SJHJOBM BSUJTU .QQMCPI OCP[ VJCPMU VQ (W-YWP *YCPI CPF CWVJQT QH 'CU[ ,CXC 5KOWNCVKQP
(TCPEKUEQ 'USWGODTG


• File:Dopplerfrequenz.gif 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPU&QRRNGTHTGSWGP\IKH -JDFOTF %%$;5#
$POUSJCVUPST 1YP YQTM 0SJHJOBM BSUJTU %JCTN[ 9JKUM[ ,CPWCT[ [[[


• File:Gnome-mime-sound-openclipart.svg 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPU
)PQOGOKOGUQWPFQRGPENKRCTVUXI -JDFOTF 2WDNKE FQOCKP $POUSJCVUPST 1YP YQTM $CUGF QP (KNG)PQOGOKOGCWFKQQRGPENKRCTV
UXI YJKEJ KU RWDNKE FQOCKP 0SJHJOBM BSUJTU 7UGT'WDWNKFGU


• File:Question_book-new.svg 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCGP3WGUVKQPADQQMPGYUXI -JDFOTF %ED[UC
$POUSJCVUPST
%TGCVGF HTQO UETCVEJ KP #FQDG +NNWUVTCVQT $CUGF QP +OCIG3WGUVKQP DQQMRPI ETGCVGF D[ 7UGT'SWC\EKQP 0SJHJOBM BSUJTU
6MIF


• File:Redshift.svg 4PVSDF JVVRUWRNQCFYKMKOGFKCQTIYKMKRGFKCEQOOQPUC4GFUJKHVUXI -JDFOTF %%$;5# $POUSJCVUPST
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Medical Instruments in the Developing World Malkin


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2.9 Fetal Monitor and Fetal Doppler


2.9.1 Clinical Use and Principles of Operation

Fetal monitors document two major functions: 1) the heart rate of the fetus, and 2) the
contractions of the mother. A normal fetal heart rate is between 110 to 160 beats a minute. The
sound of the beat is usually strong and regular. It is normal to have some changes in the fetal
heart rate during labor, but drastic changes in heart rate before or after a contraction may
indicate that the fetus is in distress. A fetus with large changes in heart rate may need to be
removed from the womb immediately, by Caesarean section.

Fetal monitoring during labor, when it is most commonly applied, has been controversial since its
inception. Some claim that fetal monitoring offers a monitoring tool that can reduce fetal
mortality and morbidity. Others blame the technology for the large increases in Caesarean
sections and the attendant maternal morbidity.

Currently, there are three widely used methods of monitoring the fetal heart rate: Doppler,
Surface Electrodes, and a Scalp Electrode.

Surface electrodes are applied directly to the mother’s body, typically with adhesive silver-silver
chloride electrodes. The surface electrode technique operates identically to a typical
electrocardiogram, but with much more complex signal processing to reduce the probability of
mistaking a maternal heart beat for a fetal heart beat. The surface electrode approach to
measuring the fetal heart rate has the advantages of being not invasive, being applicable at any
time during pregnancy, and are very low cost. However, they are subject to artifacts from the
maternal heart beat, don’t work well with certain fetal positions and can’t resolve multiple fetal
pregnancies.

For the Doppler technique, a doctor, nurse, or technician applies ultrasound gel to the end of a
flat transducer and moves it across the abdomen until a good reflection is found from the heart.
The Doppler technique is the most common as it is less prone to artifacts than the surface
electrodes and it is equally easy to apply. However, the transducer and accompanying
electronics are expensive, may require repositioning during labor, and don’t resolve multiple fetal
pregnancies well.

The fetal Doppler probe is also used by itself to detect the fetal heart beat. As a hand-held
device it can be used from about the end of the first trimester to delivery. The probe produces
ultrasonic pressure waves at about 2.5 MHz and hand-held unit produces a sound with heart
beat. A typically hand held device has no display or chart. The doctor must time or count the
heart beats to determine the fetal heart rate.

The principle of operation of the Doppler probe is the Doppler Effect. If waves of a given
frequency are transmitted to a stationary reflector, the reflected waves are of the same
frequency as those transmitted. If the reflector is moving towards the transmitter-receiver, the
reflected frequency will be higher than the transmitted frequency. In this case, the waves are
bounced off the fetal heart. The occurrence of a frequency shift is taken as the presence of a
heart beat by the machine.

Scalp electrodes are applied directly on the fetus’ head and operate in a manner identical to a
standard electrocardiogram. This approach is used only with high-risk patients, if labor is going




Equipment found in the OR, ICU and ER


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very slowly or if the external fetal monitor is not detecting the fetal heart rate. The amniotic sac
must be broken to apply the electrode. The scalp electrode gives accurate fetal
electrocardiograms. However, it is invasive, opens the amniotic sac for infection, and cannot be
easily applied to multiple fetal pregnancies.

The contractions are measured with a strain gage transducer (usually called TOCO) either
mounted externally or with a belt around the abdomen.

The fetal heart rate is displayed digitally on many units and in graphic form on a chart. Typical
fetal heart rates are in the range of 110 to 160 beats per minute. During contractions the heart
rate will decrease and revert to previous levels after the end of the contraction. If there is a
delay in the heart rate returning to its previous level it can indicate that there is fetal distress.


2.9.2 Common Problems

User errors are common with fetal monitoring. Incorrect connections of the transducers and
incorrect loading of the paper, or the loading of the wrong paper are the most common of these
problems. Power supply problems, typically dead batteries, are common with the hand held fetal
Doppler devices. Be sure that gel is being used between the ultrasonic transducer and the
patient.

The Doppler probe is the most sensitive part of both the handheld and bedside devices. When it
breaks no output is heard, even when a stethoscope or fetoscope indicate the presence of a fetal
heart beat. You can quickly check the probe operation by gently tapping the probe surface about
once per second. If this is not detected, there is certainly a probe problem.

The probe consists of the transducer assembly, the cable, and a multi-pin fixable connector. The
cable contains between 5 and 80 separate conductors. The most frequent malfunction occurs as
a result of a break in one or more of the cable conductors. Such malfunctions are usually the
result of mishandling of the cable or of soaking it with gel. The probe is expensive and typically
cannot be replaced in the developing world.

Fortunately, the cable can often be mended. The face of the probe is usually an acoustic lens. It
must be handled with care. Do not drop the probe, and avoid scratching the face with sharp
objects. Keep the probe assembly clean of oil and gel. Always clean the probe and cable with a
tissue or damp cloth, after finishing work.

The surface electrode problems are similar or identical to those discussed in the chapter on
electrocardiograms. Poor electrode function will result in no fetal heart beat being reported.
Check that the patient electrode connections are clean and in good condition. Check that the
leads to the patient are in good condition, that the conductor is not broken, and that there is not
a short circuit to the shielding that surrounds the other connectors.

The last most common problem is with the paper. The paper is often installed wrong or the
wrong paper is used with the device. Check that the digital heart beat and the paper trace are
giving the same reading when you tap the transducer, or apply the electrodes to yourself. The
chart recorders themselves are identical to those used for electrocardiograms. Check that
chapter for ideas on what could be wrong with a chart recorder.




Medical Instruments in the Developing World Malkin


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2.9.3 Suggested Minimal Testing

All of the transducers designed to measure the fetal heart rate can be used to measure your own
heart rate. For surface electrodes, you may have to attach one set of electrodes to yourself (as
the mother) and one set of electrodes to a friend (as the fetus) in order to satisfy any alarm
conditions before operating the machine. The Doppler probe should work when placed on your
chest, with the proper gel, near your heart. Check for the accuracy of both the digital display
and the paper trace by comparing their output with a measure of your own heart rate from a
watch. The two should be within 1 or 2 beats per minute of the correct rate.

For the contraction monitor, stretch the belt, or very gently press on the transducer at a rate of
about one gentle push every minute. Use a watch to verify the time between applications. The
monitor should reflect your application pressure (approximately) and rate (accurately – about
10%).

If both contraction rate and fetal heart rate are reported accurately, then the device is ready to
release to the floor.







**6.*Diagrams*and*Schematics*of*Fetal*Doppler****Featured*in*this*Section:****Jezewski,&L.&et.al.&“A&Novel&Technique&for&Fetal&heart&Rate&Estimation&for&Doppler&Ultrasound&Signal.”&BioMedical'Engineering'OnLine,'Vol.&10,&No.&92&(2011).&Retrieved&from:&http://www.biomedicalKengineeringKonline.com/content/10/1/92&&&Openstax&College.&“28.17&Fetal&Circulatory&System.”&From&the&publication:&Biology.&Rice&University:&2013,&pgs.&1274.&&&WHO.&“Foetal&Cardiac&Monitor.”&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/&* * *








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1 WHO Category / Code (under development)2 Generic name Foetal heart detector3 Specific type or variation (optional)4 GMDN name Foetal heart detector, ultrasonic5 GMDN code 350686 GMDN category 04 Electro mechanical medical devices12 Diagnostic and therapeutic radiation devices7 UMDNS name Detectors, Fetal Heart, Ultrasonic8 UMDNS code 116969 UNSPS code (optional)10 Alternative name/s (optional) Fetal heart detector, ultrasonic; Monitor, heart rate, fetal, ultrasonic; Monitor, heart sound, fetal, ultrasonic; Monitor, hemic sound, ultrasonic11 Alternative code/s (optional) S 11696; S 32624; S 39604; S 3262212 Keywords (optional) electrocardiograph (ECG), heart rate, fetal heart13 GMDN/UMDNS definition (optional) A device intended to enable audible detection of the foetal heart through the use of ultrasound.
14 Clinical or other purpose Detect, measure, and display foetal heart activity.The primary purpose of the fetal heart detector is to provide quick reassurance of fetal well-being to both the mother and the healthcare worker. The fetal heartbeat cannot be heard with an obstetric stethoscope until 24 weeks after conception. Ultrasonic fetal heart detectors can easily detect fetal heart sounds throughout the pregnancy, starting as early as 8 weeks. 15 Level of use (if relevant) Health centre, district hospital, provincial hospital, specialized hospital, General hospital
16 Clinical department/ward(if relevant) Obstetrics and Gynecology, gynecology physician office17 Overview of functional requirements Fetal heart detectors are routinely used by physicians, obstetric nurses, and community midwives to record FHR values. Abnormal readings can quickly alert the healthcare worker to possible complications.


18


Detailed requirements Microprocessor controlled equipment.LCD display with visualization of at least fetal heart rate.Integrated fetal heart processing software.Ultrasound working frequency in the range 2MHz -10% to 3MHz +10%.Sensitivity to detect fetal heart beats of at least a 10-12 weeks fetus.At least two high sensitivity equipment compatible probes provided: 2 and 3 MHz.Heart rate measurement range not smaller than 50-210 bpm with resolution not higher than 2 bpm.Audio output reproduction of the fetal heart rate with integrated speaker and with headphones.Audio volume control system integrated.At least 1 of system compatible headphones provided.At least one integrated serial port for PC connection and data transmission.Memory storage capacity of at least 4 hours of working data.Cable for data transmission.1 pair of spare system compatible headphones.At least 1 bottle of gel for patient application.Carry case for easy transportation.19 Displayed parameters FHR20 User adjustable settings Controls: volume, power on/off
21 Components(if relevant)PHYSICAL/CHEMICAL CHARACTERISTICS


NAME, CATEGORY AND CODING


PURPOSE OF USE


TECHNICAL CHARACTERISTICS




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22 Mobility, portability(if relevant) Bench top, handheld models and small tabletop units23 Raw Materials(if relevant) N/A
24 Electrical, water and/or gas supply (if relevant) Batteries, rechargeable batteries should be considered to save on the cost of replacement batteries. Electrical source requirements: Amperage: ______; Voltage: ______. Compliance with ______ electrical standards and regulations.
25 Accessories (if relevant) Mandatory
26 Sterilization process for accessories (if relevant) Mandatory
27 Consumables / reagents (if relevant)28 Spare parts (if relevant) specific spare parts to consider in the maintenance of 2 year29 Other components (if relevant)
30 Sterility status on delivery (if relevant) N/A31 Shelf life (if relevant) 10 years32 Transportation and storage (if relevant) N/A33 Labelling (if relevant) N/A
34 Context-dependent requirements Normal conditions
35 Pre-installation requirements(if relevant) None36 Requirements for commissioning (if relevant)37 Training of user/s (if relevant) user training is required38 User care(if relevant) Capable of easy sterilization with both alcohol and chlorine based agentsPatient worn straps to be detachable and washable
39 Warranty 2 years full warranty40 Maintenance tasks preventive periodical warranty41 Type of service contract None42 Spare parts availability post-warranty for 8 years43 Software / Hardware upgrade availability


PACKAGING


ENVIRONMENTAL REQUIREMENTS
TRAINING, INSTALLATION AND UTILISATION


WARRANTY AND MAINTENANCE


DOCUMENTATION


UTILITY REQUIREMENTS
ACCESSORIES, CONSUMABLES, SPARE PARTS, OTHER COMPONENTS




10/4/15 WHO_TS_61_MDs_web.xlsx 15


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44 Documentation requirements service & operation manual45 Estimated Life Span 10 years46 Risk Classification Class B (GHTF Rule 10-1); Class II (USA); Class II (EU, Japan, Canada and Australia)47 Regulatory Approval / Certification
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 IEC 61266:1994 Ultrasonics - Hand-held probe Doppler foetal heartbeat detectors - Performance requirements and methods of measurement and reporting49 Reginal / Local Standards JIS T 1506:2005 Ultrasonics -- Hand-held probe Doppler foetal heartbeat detectors -- Performance requirements and methods of measurement and reporting
50 Regulations US regulations 21 CFR part 820 21 CFR section 884.2660 monitor, heart sound, fetal, ultrasonic JP regulations MHLW Ordinance No.169 35068000 Ultrasonic foetal heart detector


SAFETY AND STANDARDS DECOMMISSIONING




**7.*Resources*for*More*Information*about*Fetal*Monitors*and*Fetal*Doppler****&&&&&




&*Fetal*Monitor*Bibliography:*&&&Developing&World&Healthcare&Technology&Laboratory.&“Fetal&Monitors.”&From&the&Publication:&“Biomedical&Technicians&Training&Program,&Session&3&v2,&Special&Topics:&Cardiac&Equipment.”&Engineering'World'Health,&March&1,&2011,&p.&115K159.&&& WHO.&“Fetal&Monitor.”&From&the&publication:&Core'Medical'Equipment.&Geneva,&Switzerland,&2011.&&& WHO.&“Fetal&Heart&Detector,&Ultrasonic.”&From&the&publication:&Core'Medical'Equipment.&Geneva,&Switzerland,&2011.&&&WHO.&“Neonatal&Physiological&Monitor.”&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/&&&&&&&&&&&*********




*Fetal*Doppler*Bibliography:*&&&Cooper,&Justin&and&Alex&Dahinten&for&EWH.&“Fetal&Doppler&Preventative&Maintenance.”&From&the&publication:&&Medical'Equipment'Troubleshooting'Flowchart'Handbook.&Durham,&NC:&Engineering&World&Health,&2013.&&&Cooper,&Justin&and&Alex&Dahinten&for&EWH.&“Fetal&Doppler&Troubleshooting&Flowchart.”&From&the&publication:&Medical'Equipment'Troubleshooting'Flowchart'Handbook.&Durham,&NC:&Engineering&World&Health,&2013.&&&Jezewski,&L.&et.al.&“A&Novel&Technique&for&Fetal&heart&Rate&Estimation&for&Doppler&Ultrasound&Signal.”&BioMedical'Engineering'OnLine,'Vol.&10,&No.&92&(2011).&Retrieved&from:&http://www.biomedicalKengineeringKonline.com/content/10/1/92&& &Malkin,&Robert.&“Fetal&Monitor&and&Fetal&Doppler:&Use&and&Operation.”&From&the&publication:&&Medical'Instrumentation'in'the'Developing'World.&Engineering&World&Health,&2006.&&& Openstax&College.&“28.17&Fetal&Circulatory&System.”&From&the&publication:&Biology.&Rice&University:&2013,&pgs.&1274.&&&WHO.&“Foetal&Cardiac&Monitor.”&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/&&&Wikipedia.&“Doppler&Effect.”&Wikipedia,'p.'1K8.&Retrieved&from:&&https://en.wikipedia.org/wiki/Doppler_effect&* *




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