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Blood Pressure Units

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Blood Pressure Units

A blood pressure unit is used to determine the pressure inside the blood vessels of a patient.  There are two numbers that are important when taking a patient’s blood pressure, they are the systolic and diastolic pressures.  The systolic pressure is higher than the diastolic in a healthy adult and it corresponds to when the heart contracts.  While the diastolic number corresponds to when the heart is relaxed between beats.  Blood pressure readings are read as a fraction in a way for example 120/80 or 120 over 80 and readings can be classified as either low, normal, or high.  A person with low blood pressure has a blood pressure lower than 90/60 and the only real risk associated with this being that the patient may feel light headed or faint if it gets too low.  Normal blood pressure is any reading that is higher than 90/60 and lower than 140/90.  High blood pressure is any reading higher than 140/90 there are many health risks associated with high blood pressure and any patient with a blood pressure on the high side should consider changing their lifestyle.
How it works

There are two different types of blood pressure units either an automatic or a manual but they both work on the same principle.  First, the cuff is wrapped around the patients arm then the cuff is inflated to a point where it cuts off flow.  Next, the pressure in the cuff is slowly deflated until vibrations or Korotkoff sounds are heard.  When the sounds are first heard this is the systolic pressure of the patient and when the sounds stop this is the diastolic pressure.


Preventative Maintenance

The preventative maintenance of a blood pressure unit consists of, if applicable, an electrical safety inspection followed by a physical inspection of the unit and all accessories.  Next the blood pressure unit is tested for accuracy at different blood pressures and the system is tested for leaks.  Finally, the battery is checked to ensure that it has been changed within the past 2 years.  This is done for 2 reasons the first being so the battery does not corrode and damage the inside electronics.  The second reason being, so there is a functional battery in case of an emergency.

Common Errors

Electrical safetyElectrical safety failures are failures found during electrical safety testing and can potentially pose a risk to the patient.  This may be a high leakage current, ground wire resistance or too high of an operating current.

Damaged cuff or air hoseA damaged blood pressure cuff or air hose is common especially in a device that is highly used and this is because the Velcro gets worn to a point where it will not hold properly. Blood pressure units also develop leaks over time in the cuff itself or in any of the connectors used to interface the cuff with the air hose.  These failures can result in an error or false readings.

Internal Malfunctions – An internal malfunction of a blood pressure unit typically is one of 3 things.  First, the motor on the unit may fail; this will cause the cuff to not inflate fast enough or at all.  Second, is the pressure transducer which is responsible for reading the pressure inside the circuitry and detecting the vibrations of the patient’s blood pressure. The final internal error that can occur is an internal leak which may give the same errors and false readings as a leaky cuff.

Calibration failure – If a unit will not calibrate when attempted it can be caused by a main board failure, pressure transducer failure or because of a leak in the system.  When any of these typically the unit will need to be further assessed to determine exactly what is the cause.


How to get an accurate measurement

  • Allow the patient to rest for 5 minutes or more with their arm at heart level and their feet flat on the floor.
  • Find the right cuff for the patient as there are multiple sizes for patients with different size arms (If the patient fits in 2 cuff sizes pick the smaller of the 2).
  • Wrap the cuff around the arm with the artery marker in line with the patient’s brachial artery so you can comfortably fit one finger under the cuff.
  • Inflate the cuff and instruct the patient to no talk or make any sudden movements as this can mimic Korotkoff sounds and give false reading.
  • If more even more accurate readings are desired repeat the process on both arms and average the total.

The TRH Value

The added valve of choosing TRH Services to complete your maintenance and repairs on your blood pressure units is that we will ensure that your device will be in great working condition for you and your patients for the next year and it will be fully certified.  At TRH Services our expertise can help educate you on your blood pressure systems and make sure that your unit is in top performance. We can provide onsite service to your facility if you are located in South-Western Ontario (London, Toronto, Kitchener, Waterloo, Cambridge, Guelph, Hamilton, etc.).


Common Blood Pressure Units

Listed below is a short list of some common blood pressure units that we work on, a regular basses:

ManufacturerModel Number
A&D Engineering Inc.UA-779
A&D Engineering Inc.UB-521
A&D Engineering Inc.UA-787
A&D Engineering Inc.UA-774
A&D Engineering Inc.UA-767PC
A&D Engineering Inc.UA-767 Plus
A&D Engineering Inc.UA-767
A&D Engineering Inc.UA-705
A&D Engineering Inc.UA-704
A&D Engineering Inc.UA-702
A&D Engineering Inc.UA-631V
A&D Engineering Inc.UA-1020CN
A&D Engineering Inc.5534
A&D Engineering Inc.UA-789
ActusHand Held
AlmedicHand Held
Almedica AgHand Held
ALPK2Hand Held
Amber SpaN/A
American Diagnostic Corp. (ADC)6013
American Diagnostic Corp. (ADC)6023
American Diagnostic Corp. (ADC)Hand Held
American Diagnostic Corp. (ADC)6021
AMG Medical IncProfessional Series
AMG Medical IncHand Held
AMG Medical Inc106-960
AMG Medical Inc106-955
AMG Medical Inc106-950
AMG Medical Inc106-945
AMG Medical Inc106-940
AMG Medical Inc106-920
Barrington DiagnosticsHand Held
Barrington DiagnosticsFloor Model
BMSHand Held
Body CheckHand Held
BpTRU Medical DevicesBPM-200
Briggs Healthcare04-620-001
BV Medical StandardHand Held
Chattanooga GroupPressure Feedback
E.R.P LTD.MS-001
HealthmateHand Held
Heine GermanyWall
Heine GermanyHand Held
Heine GermanyGamma G7
Heine GermanyGamma XXL Wall Mount
Heine GermanyGamma G5
Heine GermanyGamma XXL LF
Henry ScheinHand Held
HoMedics, LLC.BPA-110-2CA
HoMedics, LLC.BP-A06-00CA
IMCOHand Held
Keller Medical SpecialtiesKMS890
Keller Medical SpecialtiesKMS 890
LabTronHand Held
Life Brand5534
Mabis Health Care Inc.Hand Held Sphygmomanometer
Mabis Health Care Inc.Hand Held
Mabis Health Care Inc.04-244-001
Mabis Match MatesHand Held
Mansfield Medical Distributors LtdHand Held
McCoy RigbySingle Tube
Medisana AGETP
Microlife CorporationBP3MX1-1
N/AFloor Model
N/AHand Held
Nasco Iso PlasticsLF03956
Omron Healthcare Inc.12-605
Omron Healthcare Inc.BP760CAN (HEM-7220-CA)
Omron Healthcare Inc.HEM-629
Omron Healthcare Inc.HEM-605
Omron Healthcare Inc.HEM-601
Omron Healthcare Inc.HEM-431
Omron Healthcare Inc.HEM-412CRELN2
Omron Healthcare Inc.HEM – 7411CAN
Omron Healthcare Inc.Hand Held
Omron Healthcare Inc.BP785CAN
Omron Healthcare Inc.BP785 (HEM-7222-Z)
Omron Healthcare Inc.BP762CAN
Omron Healthcare Inc.BP760CAN
Omron Healthcare Inc.BP755CAN-CD6
Omron Healthcare Inc.BP742CAN (HEM-7200-CA)
Omron Healthcare Inc.BP710CAN
Omron Healthcare Inc.BP710(HEM-7113-Z)
Omron Healthcare Inc.964804
Omron Healthcare Inc.705IT
Omron Healthcare Inc.412CREL
Omron Healthcare Inc.2Z01998L
Omron Healthcare Inc.BP785
Omron Healthcare Inc.HEM-7000-CANCS
Omron Healthcare Inc.HEM-650
Omron Healthcare Inc.HEM-712c
Omron Healthcare Inc.HEM-780
Omron Healthcare Inc.HEM-775CAN
Omron Healthcare Inc.HEM-775 CAN
Omron Healthcare Inc.HEM-773
Omron Healthcare Inc.HEM-757
Omron Healthcare Inc.HEM-741CAN
Omron Healthcare Inc.HEM-741
Omron Healthcare Inc.HEM-7220-CACS
Omron Healthcare Inc.HEM-780CANN
Omron Healthcare Inc.HEM-712CN2
Omron Healthcare Inc.HEM-780N2
Omron Healthcare Inc.HEM711LXCAN
Omron Healthcare Inc.HEM-711DLXCAN
Omron Healthcare Inc.HEM-711DLX
Omron Healthcare Inc.HEM-711DCXCAN
Omron Healthcare Inc.HEM-711ACCANN
Omron Healthcare Inc.HEM-711ACCANIN
Omron Healthcare Inc.HEM-711
Omron Healthcare Inc.HEM-705CPCAN
Omron Healthcare Inc.HEM-705CP
Omron Healthcare Inc.HEM-7121-CA
Omron Healthcare Inc.HEM-7220-CA
Omron Healthcare Inc.HEM-780CAN
Omron Healthcare Inc.HEM-650CANN
Omron Healthcare Inc.N/A
Omron Healthcare Inc.Marshall 85
Omron Healthcare Inc.HEM-907xl
Omron Healthcare Inc.HEM-790ITCAN
Omron Healthcare Inc.HEM790ITCAN
Omron Healthcare Inc.HEM-780N3
ParaMed Technology Inc.910
Prestige MedicalOne Pieace
Prestige MedicalHand Held
Rexall Brands CorpRX800
Rexall Brands CorpRX100
Riester GmbHWall Mount
Riester GmbHFloor Model
Riester GmbHMinimus II
Shoppers Drug Mart, Ltd.BC03
Smiths Medical PM INC.N/A
Smiths Medical PM INC.Mini-Torr Plus
SphygmomanometerHand Held
Summit Doppler SystemsHand Held
Sunbeam-Oster Company7621
SunTech Medical Inc.Hand Held
TaylorMOD II
TaylorHand Held
TechnomedicHand Held
Thermor Ltd.33601
Thermor Ltd.3MS1-4K
Thermor Ltd.3AL1-3E
Tremblay Harrison, Inc.ABP-A1
Tyco Healthcare Group LPN/A
Tyco Healthcare Group LPWall mounted
Tyco Healthcare Group LPWall Mount
Tyco Healthcare Group LPWall Model
Tyco Healthcare Group LPWall
Tyco Healthcare Group LPSuper Shock Resistant
Tyco Healthcare Group LPOne Piece
Tyco Healthcare Group LPMercury Wall Mount
Tyco Healthcare Group LPMercury
Tyco Healthcare Group LPHand Held
Tyco Healthcare Group LPHand
Tyco Healthcare Group LPFloor Model
Tyco Healthcare Group LPDual Tube
Tyco Healthcare Group LPCart
Tyco Healthcare Group LPSingle Tube
UtilityHand Held
Veridian Healthcare LLCFloor Model
VetlineVet HDO
VSM MedTech LtdBP3-300
W. A. Baum Co. Inc.N/A
W. A. Baum Co. Inc.Wall Model
W. A. Baum Co. Inc.Wall Mount
W. A. Baum Co. Inc.Wall
W. A. Baum Co. Inc.Standby
W. A. Baum Co. Inc.Riester
W. A. Baum Co. Inc.Mercury Wall Mount
W. A. Baum Co. Inc.Mercury
W. A. Baum Co. Inc.Hand Held
W. A. Baum Co. Inc.Floor Model
W. A. Baum Co. Inc.Baumanometer
W. A. Baum Co. Inc.1050
W. A. Baum Co. Inc.0950NL
W. A. Baum Co. Inc.Wall Mounted
Wal-Mart Canada20457
Welch AllynWall Mount
Welch AllynN344
Welch AllynFloor Model
Welch AllynD-72417
Welch Allyn5300
Welch AllynHand Held
Yamasu PakistanHand Held




Written By: Greg Kishimoto

Edited By: Tyler Hasenpflug CET

2 Responses

  1. Jeff Heilbraun

    Hello, I hope all is going well. I wanted to see if you still support the maintenance of the BpTRU-200 device. I work for a cardiac safety core lab in support of the pharmaceutical R&D arena and have an inventory of BpTRU -200 devices. With the BpTRU company closing I am trying to identify resources for technical support and maintenance.

    Thanks in advance for your follow-up

    Jeff Heilbraun
    VP Strategic Development
    +1-301-792-5073 cell phone

    • Tyler Hasenpflug

      HI Jeff,

      If you need more information on this please e-mail me at info@trhservices.ca and I will gladly assist you.