SlideShare una empresa de Scribd logo
1 de 64
Descargar para leer sin conexión
INTRODUCTION
TO
STETHOSCOPE &
SPHYGMOMANOMETER
Dr.Sudeesh Shetty,
Assistant Professor,
Department of Roganidan and Vikriti Vijnana,
Mobile:+91-9481818631
Email: drsudeeshshetty@gmail.com
drsudeeshshetty@gmail.com 1
•The stethoscope (stethophone) is an acoustic medical
device for auscultation, or listening to the internal sounds
of an animal or human body
•Listen to intestines and blood flow in arteries and veins.
drsudeeshshetty@gmail.com 2
STETHOSCOPE
drsudeeshshetty@gmail.com 3
drsudeeshshetty@gmail.com 4
drsudeeshshetty@gmail.com 5
A French doctor named Rene -Theophile- Hyacinthe-Laennec
invented the first stethoscope in 1816.
Laennec's Stethoscope
drsudeeshshetty@gmail.com 6
• In the early 1850's there was a
rush of designs for a new
stethoscope that used both ears.
• This new 'Bi-aural' or 'Binaural'
instrument was felt to be the
future of auscultation.
Binaural Stethoscope/ Predeccessor to Modern Stethoscope
drsudeeshshetty@gmail.com 7
 Acoustic stethoscopes are familiar to most people, and
operate on the transmission of sound from the chest piece,
via air-filled hollow tubes, to the listener's ears
Acoustic stethoscopes/Modern Stethoscope
drsudeeshshetty@gmail.com 8
Parts:
•Ear pieces, binaural pieces, flexible tubing, a stem, and a
chestpiece.
drsudeeshshetty@gmail.com 9
drsudeeshshetty@gmail.com 10
Principle-Stethoscope works on the principle of multiple
reflection of sound.
Working-
• When a doctor or nurse places a stethoscope diaphragm on a
patient's chest, sound waves traveling through the patient's
body cause the flat surface of the diaphragm to vibrate.
• Those vibrations would travel outward, but because the
vibrating object is attached to a tube, the sound waves are
channeled in a specific direction.
• Each wave bounces, or reflects, off the inside walls of the
rubber tube, a process called multiple reflection.
• In this way, each wave, in succession, reaches the eartips, or
rubber nubs on the ends of the device, and finally the listener's
eardrums.
drsudeeshshetty@gmail.com 11
Specifications
Stethoscope Head Specifications
• The size of an adult stethoscope head is 45mm, while a pediatric head is
35mm.
• Some stethoscopes have single chest pieces, which mean they are
specifically made for either an adult or pediatric patient. However, some
have dual heads.
• These stethoscopes are designed with both chest pieces and can be used
for either adults or children.
• The chest piece is made from surgical stainless steel.
drsudeeshshetty@gmail.com 12
Tube Specifications
• The tubing varies on each model. Stethoscopes with tapered inner
bores provide a better sound transmission when listening to the heart
or lungs.
• If the stethoscope has extra-thick tubing, outside noise is reduced.
• You can choose between stethoscopes with a 21-inch single bore
flexible tubing or 19-inch two-in-one bi-lumen tubing.
• The length of the stethoscope can vary from 27 inches to 29 inches.
• It can weigh between 6 ounces and 7.6 ounces.
• Tubing can come in black, blue, green, orange, pink and burgundy
colors.
drsudeeshshetty@gmail.com 13
Type of Stethoscope
1.ACOUSTIC STETHOSCOPE-
• This stethoscope-operate on the transmission of sound from the
chestpiece, via air-filled hollow tubes, to the listener's ears
• Demerit:-Demerit of acoustic stethoscopes was that the sound level is
extremely low.
• Price of stethoscope:- It is vary from Rs-300 to Rs-20,000.
drsudeeshshetty@gmail.com 14
drsudeeshshetty@gmail.com 15
2.Electronic stethoscope
• An electronic stethoscope (or) overcomes the low sound levels by
electronically amplifying body sounds and may be broadcast through
loudspeakers, but in both instances the results are mediocre
• The simplest and least effective method of sound detection is achieved
by placing a microphone in the chest piece.
• can be a wireless device, can be a recording device, and can provide
noise reduction, signal enhancement, and both visual and audio output.
•Price of stethoscope:- It is vary from Rs-10,000 to Rs-50,000.
drsudeeshshetty@gmail.com 16
drsudeeshshetty@gmail.com 17
drsudeeshshetty@gmail.com 18
drsudeeshshetty@gmail.com 19
drsudeeshshetty@gmail.com 20
SPHYGMOMANOMETER
• A sphygmomanometer, blood pressure meter, or blood pressure gage (also referred
to as a sphygmometer) is a device used to measure blood pressure.
• The sphygmomanometer was invented by Samuel Siegfried Karl Ritter von
Basch in the year 1881.
• Scipione Riva-Rocci introduced a more easily used version in 1896.
drsudeeshshetty@gmail.com 21
Construction/Specifications
• A sphygmomanometer consists of an inflatable cuff, a measuring unit
(the mercury manometer, or aneroid gauge), and a mechanism for
inflation which may be a manually operated bulb and valve or a pump
operated electrically.
drsudeeshshetty@gmail.com 22
Working :
• There are two numbers in a blood pressure reading: systolic and
diastolic.
• When the doctor puts the cuff around your arm and pumps it up, what
he/she is doing is cutting off the blood flow with the pressure exerted by
the cuff.
• As the pressure in the cuff is released, blood starts flowing again and
the doctor can hear the flow in the stethoscope.
• The number at which blood starts flowing (120) is the measure of the
maximum output pressure of the heart (systolic reading).
• The doctor continues releasing the pressure on the cuff and listens until
there is no sound.
• That number (80) indicates the pressure in the system when the heart is
relaxed (diastolic reading).
drsudeeshshetty@gmail.com 23
• If the numbers are too high, it means that the heart is
having to work too hard because of restrictions in the
pipes.
• Other things that can increase the blood pressure include
deposits in the pipes and a loss of elasticity as the blood
vessels age.
• High blood pressure can cause the heart to fail (from
working too hard), or it can cause kidney failure (from
too much pressure).
For example, a typical reading might be 120/80 or 110/80
mm Hg.
drsudeeshshetty@gmail.com 24
1. Should be Portable mercurial type.
2. Should have ISI mark.
3. Should have ON and OFF provision for mercury reservoir.
4. Should have a measuring range from 0 to 300 mmHg.
5. Should be provided with adult arm cuffs of size medium & large and paediatric
cuff.
6. The control valve should have a knurled thumb control device.
7. The leak rate should not exceed 10 mm of mercury per minute.
8. The manometer scale markings and graduations should be permanent and clearly
visible and filled with pigments.
9. The internal diameter of the manometer glass tube should be 4.1 ± 0.1 mm and
the thickness not less than 2 mm.
10. All plastic parts, if any used should not crack, flake, peel or disintegrate in
normal use.
11. The inflating rubber bag should be capable of withstanding an internal pressure
of 450 mmHg without leaking.
12. The inflating bulb should be soft and should not have any joints or ridges.
Technical Specification
drsudeeshshetty@gmail.com 25
Aneroid sphygmomanometers :
• Mmechanical types with a dial are in common use; they require
regular calibration checks, unlike mercury manometers.
• Aneroid sphygmomanometers are considered safer than mercury
based, although less accurate.
• A major cause of departure from calibration is mechanical jarring.
• Aneroids mounted on walls or stands are less susceptible to this
particular problem.
Mercury sphygmomanometers :
• They are considered to be the gold standard.
• They measure blood pressure directly by observing the height of a
column of mercury; errors of calibration cannot occur
TYPES
drsudeeshshetty@gmail.com 26
Digital:
• Digital sphygmomanometers are automated, providing blood pressure
reading without needing someone to operate the cuff or listen to the
blood flow sounds.
• However digital types are less accurate.
• Some healthcare providers use digital for screening but use manual
sphygmomanometers to validate readings in some situations.
Price:-The price of sphygmomanometer vary from Rs-600 to
Rs-6000.
drsudeeshshetty@gmail.com 27
Blood pressure measurement
• Arterial blood pressure is most commonly measured via
a sphygmomanometer, which historically used the height of a column
of mercury to reflect the circulating pressure.
• Blood pressure values are generally reported in millimeters of
mercury (mmHg), though aneroid and electronic devices do not
contain mercury. For each heartbeat, blood pressure varies between
systolic and diastolic pressures.
• Systolic pressure is peak pressure in the arteries, which occurs near
the end of the cardiac cycle when the ventricles are contracting.
Diastolic pressure is minimum pressure in the arteries, which occurs
near the beginning of the cardiac cycle when the ventricles are filled
with blood.
drsudeeshshetty@gmail.com 28
• Systolic and diastolic arterial blood pressures are not static but undergo
natural variations from one heartbeat to another and throughout the day
(in a circadian rhythm).
• They also change in response to stress, nutritional factors, drugs,
disease, exercise, and momentarily from standing up.
• Sometimes the variations are large.
• Along with body temperature, respiratory rate, and pulse rate, blood
pressure is one of the four main vital signs routinely monitored by
medical professionals and healthcare providers.
drsudeeshshetty@gmail.com 29
Location of measurement
• The standard location for blood pressure measurement is the
brachial artery.
• Monitors that measure pressure at the wrist and fingers have
become popular, but it is important to realize that systolic and
diastolic pressures vary substantially in different parts of the
arterial tree with systolic pressure increasing in more distal
arteries, and diastolic pressure decreasing.
1.INVASIVE 2.NONINVASIVE
drsudeeshshetty@gmail.com 30
Basic techniques of blood pressure measurement:
drsudeeshshetty@gmail.com 31
Non-invasive
• The non-invasive auscultatory and oscillometric measurements
are simpler and quicker than invasive measurements, require less
expertise, have virtually no complications, are less unpleasant
and less painful for the patient.
• However, non-invasive methods may yield somewhat lower
accuracy and small systematic differences in numerical results.
• Non-invasive measurement methods are more commonly used
for routine examinations and monitoring.
1.Palpation/Manual /Placatory method
• A minimum systolic value can be roughly estimated
by palpation, most often used in emergency situations, but
should be used with caution
• A more accurate value of systolic blood pressure can be
obtained with a sphygmomanometer and palpating the radial
pulse
drsudeeshshetty@gmail.com 32
2.Auscultatory
• The auscultatory method (from the Latin word for "listening")
uses a stethoscope and a sphygmomanometer
• Listening with the stethoscope to the brachial artery at
the antecubital area of the elbow, the examiner slowly releases
the pressure in the cuff.
• When blood just starts to flow in the artery, the turbulent
flow creates a "whooshing" or pounding (first Korotkoff sound).
• The pressure at which this sound is first heard is the systolic
blood pressure.
• The cuff pressure is further released until no sound can be heard
(fifth Korotkoff sound), at the diastolic arterial pressure.
• The auscultatory method is the predominant method of clinical
measurement
drsudeeshshetty@gmail.com 33
• Although the auscultatory method using mercury sphygmomanometer is
regarded as the ‘gold standard’ for office blood pressure measurement,
widespread implementation of the ban in use of mercury
sphygmomanometers continues to diminish the role of this technique.
• The situation is made worse by the fact that existing aneroid manometers,
which use this technique, are less accurate and often need frequent
calibration.
• New devices known, as “hybrid” sphygmomanometers, have been
developed as replacement for mercury devices.
• Basically, these devices combine the features of both electronic and
auscultatory devices such that the mercury column is replaced by an
electronic pressure gauge, similar to oscillometric devices, but the blood
pressure is taken in the same manner as a mercury or aneroid device, by an
observer using a stethoscope and listening for the Korotkoff sounds
drsudeeshshetty@gmail.com 34
drsudeeshshetty@gmail.com 35
3. The oscillometric technique
• The oscillometric method was first demonstrated in 1876 and
involves the observation of oscillations in the sphygmomanometer
cuff pressure which are caused by the oscillations of blood flow, i.e.,
the pulse.
• The electronic version of this method is sometimes used in long-term
measurements and general practice.
• It uses a sphygmomanometer cuff, like the auscultatory method, but
with an electronic pressure sensor (transducer) to observe cuff
pressure oscillations, electronics to automatically interpret them, and
automatic inflation and deflation of the cuff.
• The pressure sensor should be calibrated periodically to maintain
accuracy.
drsudeeshshetty@gmail.com 36
This was first demonstrated by Marey in 1876,and it was subsequently shown that
when the oscillations of pressure in a sphygmomanometer cuff are recorded during
gradual deflation, the point of maximal oscillation corresponds to the mean intra-
arterial pressure.The oscillations begin at approximately systolic pressure and
continue below diastolic, so that systolic and diastolic pressure can only be estimated
indirectly according to some empirically derived algorithm. This method is
advantageous in that no transducer need be placed over the brachial artery, and it is
less susceptible to external noise (but not to low frequency mechanical vibration),
and that the cuff can be removed and replaced by the patient during ambulatory
monitoring, for example, to take a shower. The main disadvantage is that such
recorders do not work well during physical activity when there may be considerable
movement artifact. The oscillometric technique has been used successfully in
ambulatory blood pressure monitors and home monitors. It should be pointed out that
different brands of oscillometric recorders use different algorithms, and there is no
generic oscillometric technique. Comparisons of several different commercial models
with intra-arterial and Korotkoff sound measurements, however, have shown
generally good agreement.
drsudeeshshetty@gmail.com 37
4.Ultrasound techniques
Devices incorporating this technique use an ultrasound transmitter and receiver
placed over the brachial artery under a sphygmomanometer cuff. As the cuff is
deflated, the movement of the arterial wall at systolic pressure causes a Doppler
phase shift in the reflected ultrasound, and diastolic pressure is recorded as the
point at which diminution of arterial motion occurs. Another variation of this
method detects the onset of blood flow at systolic pressure, which has been found
to be of particular value for measuring pressure in infants and children. In patients
with very faint Korotkoff sounds (for example those with muscular atrophy)
placing a Doppler probe over the brachial artery may help to detect the systolic
pressure, and the same technique can be used for measuring the ankle-brachial
index, in which the systolic pressures in the brachial artery and the posterior tibial
artery are compared, to obtain an index of peripheral arterial disease.
drsudeeshshetty@gmail.com 38
5.The finger cuff method of Penaz
This interesting method was first developed by Penaz and works on the principle of
the “unloaded arterial wall.” Arterial pulsation in a finger is detected by a photo-
plethysmograph under a pressure cuff. The output of the plethysmograph is used to
drive a servo-loop, which rapidly changes the cuff pressure to keep the output
constant, so that the artery is held in a partially opened state. The oscillations of
pressure in the cuff are measured and have been found to resemble the intra-arterial
pressure wave in most subjects This method gives an accurate estimate of the
changes of systolic and diastolic pressure when compared to brachial artery
pressures; the cuff can be kept inflated for up to 2 hours. It is now commercially
available as the Finometer and Portapres recorders and has been validated in several
studies against intra-arterial pressures.The Portapres enables readings to be taken
over 24 hours while the subjects are ambulatory, although it is somewhat
cumbersome.
drsudeeshshetty@gmail.com 39
Invasive Method
• There are a variety of invasive vascular pressure monitors for
trauma, critical care, and operating room applications.
• These include single pressure, dual pressure, and multi-parameter
(i.e. pressure / temperature).
• The monitors can be used for measurement and follow-up of
arterial, central venous, pulmonary arterial, left atrial, right atrial,
femoral arterial, umbilical venous, umbilical arterial, and
intracranial pressures.
drsudeeshshetty@gmail.com 40
drsudeeshshetty@gmail.com 41
Arterial blood pressure is most accurately measured invasively through an arterial
line. Invasive arterial pressure measurement with intravascular cannulae involves
direct measurement of arterial pressure by placing a cannula needle in an artery
(usually radial, femoral, dorsalis pedis or brachial). The cannula is inserted either
via palpation or with the use of ultrasound guidance.The cannula must be
connected to a sterile, fluid-filled system, which is connected to an electronic
pressure transducer. The advantage of this system is that pressure is constantly
monitored beat-by-beat, and a waveform (a graph of pressure against time) can be
displayed. This invasive technique is regularly employed in human and
veterinary intensive care medicine, anesthesiology, and for research purposes.
Cannulation for invasive vascular pressure monitoring is infrequently associated
with complications such as thrombosis, infection, and bleeding. Patients with
invasive arterial monitoring require very close supervision, as there is a danger of
severe bleeding if the line becomes disconnected. It is generally reserved for
patients where rapid variations in arterial pressure are anticipate
drsudeeshshetty@gmail.com 42
Technical issues with measurement from the arm
• There are important potential sources of error with measurements from the
upper arm, which are discussed in the following sections.
Effects of posture
• There is no consensus as to whether blood pressure should be routinely
measured while seated or supine, although most guidelines recommend sitting.
• In a survey of 245 subjects of different ages, Netea et al found that systolic
pressures were the same in both positions, but there was a systematic age-
related discrepancy for diastolic pressure such that at the age of 30 the sitting
diastolic was about 10 mm Hg higher than the supine reading, whereas at the
age of 70 the difference was only 2 mm Hg.
drsudeeshshetty@gmail.com 43
Body position
• Blood pressure measurements are also
influenced by the position of the arm.
• As shown in, there is a progressive
increase in the pressure of about 5 to 6
mm Hg as the arm is moved down from
the horizontal to vertical position.
• These changes are exactly what would be
expected from the changes of hydrostatic
pressure.
• It is also important that the patient’s back
be supported during the measurement; if
the patient is sitting bolt upright the
diastolic pressure may be up to 6.5 mm
Hg higher than if sitting back.
drsudeeshshetty@gmail.com 44
Ambulatory monitors
First developed almost 40 years ago, ambulatory blood pressure monitoring is only
now beginning to find acceptance as a clinically useful technique. Recent technologic
advances have led to the introduction of monitors that are small and relatively quiet
and that can take up to 100 readings of blood pressure over 24 hours while patients go
about their normal activities. They are reasonably accurate while the patient is at rest
but less so during physical activity.
drsudeeshshetty@gmail.com 45
drsudeeshshetty@gmail.com 46
Thresholds for intervention
BP ≥ 220/120 mmHg: treat immediately
BP >180-189/110/119 mmHg: confirm over 1-2 weeks, then treat
BP 160-179/100-109 mmHg: with CVD complications: confirm
over 3-4 weeks, then treat
BP 140-159/90-99 mmHg: with CVD risk confirm over 12 weeks,
then treat.
drsudeeshshetty@gmail.com 47
Blood pressure measurement sources of error
Errors due to manometer
Errors due to cuff
Errors due to the observer
Errors due to the patient.
drsudeeshshetty@gmail.com 48
Manometers – automatic disadvantages
Inadequate choice of cuff sizes
Large cuffs are long enough but too deep
Need for the equivalent of the ‘alternative adult cuff’ only
available with the mercury manometer.
drsudeeshshetty@gmail.com 49
BP measurement
Three or more readings, separated by 1 minute
Discard first reading and average last two
If large difference take further readings.
drsudeeshshetty@gmail.com 50
BP measurement -cuffs
Cuff too small or too big
Normal cuff too small for 15% of patients
Cuff not level with the heart
Leaky rubber tubing or bladder
Faulty inflation/deflation device
Applies to mercury manometers only.
drsudeeshshetty@gmail.com 51
Cuff sizes
Type Size Suitability
Adult 12cm by 23cm
for smaller
arms
Alternative
cuff
12cm by 36cm
will cover 95%
arms
Large adult 15cm by 36cm
Often too wide
for ‘fat’ arms
drsudeeshshetty@gmail.com 52
Cuff Arm
circumference
(cm)
Bladder width
(cm)
Bladder length
(cm)
Newborn <6 3 6
Infant 6–15 5 15
Child 16–21 8 21
Small adult 22–26 10 24
Adult 27–34 13 30
Large adult 35–44 16 38
Adult thigh 45–52 20 42
drsudeeshshetty@gmail.com 53
6% of hypertensives can have as much as a 10 mmHg
difference between arms
If BP higher in one arm than the other, this arm must be
used from then on
Document this in records so that everyone uses the same
arm.
Which arm?
drsudeeshshetty@gmail.com 54
Technique
Patient seated and relaxed, not talking, legs uncrossed
Tight arm clothing removed
Correct cuff size
Arm supported with cuff horizontal with heart
Inform patient of discomfort and that several measurements will be
taken
Mercury manometer on firm and level surface at eye level
Locate brachial or radial pulse.
drsudeeshshetty@gmail.com 55
Technique – cont’d
Place stethoscope gently over brachial artery
Inflate mercury rapidly, 30 mmHg above occlusion of pulse
Deflate very slowly, 2 mmHg per second
Record first of regular sounds (systolic BP)
Record diastolic as disappearance of sound
Record measurements to the nearest 2 mmHg
Repeat twice more and average last two.
drsudeeshshetty@gmail.com 56
BP measurement – observer
Mercury column not level with the eyes
Failure to hear the Korotkoff sounds
Wrong diastolic endpoint (K4 or K5)
Subjective detection of Korotkoff sounds
Rapid cuff deflation
Single one off reading.
drsudeeshshetty@gmail.com 57
Stethoscope
Good quality
Short tubing
Well fitting ear pieces (cleaned regularly)
Place gently over the brachial artery
Avoid touching the cuff and tubing.
drsudeeshshetty@gmail.com 58
Posture
Routine - seated
Standing in patients with symptoms or diabetic (diabetic
nephropathy) and the elderly
Supine position unnecessary, inconvenient and cuff position often
below the heart.
drsudeeshshetty@gmail.com 59
BP measurement – patient
Anxiety and unfamiliarity
Animated discussion about the latest news
Ambient temperature
Full bladder!
Postural hypotension
Difference between arms.
drsudeeshshetty@gmail.com 60
Patient
Consent is taken as read when patient rolls up sleeve
Explain the procedure, that it may be a little uncomfortable and that
several readings will be taken
Seated, relaxed, not speaking
Tight arm clothing removed
Arm supported (not hyper extended)with cuff level with the heart.
drsudeeshshetty@gmail.com 61
Explanation to the patient
Tell the patient their blood pressure reading
Write BP down – use co-operation cards
Give relevant leaflets/booklets on life style issues (not too many at a
time)
Reassure patient that this is a risk factor not a disease (unless left
untreated)
Do not lose to follow-up.
drsudeeshshetty@gmail.com 62
‘White coat’ hypertension
Effective method of diagnosing a rise in blood pressure
associated with having blood pressure measured
Maybe from anxiety
10-20% of subjects labelled ‘hypertensive’ may have
‘white coat’ effect.
drsudeeshshetty@gmail.com 63
THANK YOU
drsudeeshshetty@gmail.com 64

Más contenido relacionado

La actualidad más candente (20)

Pulse oxymetry
Pulse oxymetryPulse oxymetry
Pulse oxymetry
 
Blood pressure
Blood pressure Blood pressure
Blood pressure
 
Measurement of Blood Pressure
Measurement of Blood PressureMeasurement of Blood Pressure
Measurement of Blood Pressure
 
Blood pressure
Blood pressureBlood pressure
Blood pressure
 
Suction
SuctionSuction
Suction
 
The Glucometer
The GlucometerThe Glucometer
The Glucometer
 
Glucose meter
Glucose meterGlucose meter
Glucose meter
 
Pulse oximeter
Pulse oximeterPulse oximeter
Pulse oximeter
 
universal precautions
 universal precautions universal precautions
universal precautions
 
Body Temperature
Body TemperatureBody Temperature
Body Temperature
 
Measurement of blood pressure in humans
Measurement of blood pressure in humansMeasurement of blood pressure in humans
Measurement of blood pressure in humans
 
Pulse
PulsePulse
Pulse
 
Defibrillators
DefibrillatorsDefibrillators
Defibrillators
 
Vital sign
Vital signVital sign
Vital sign
 
Syringe
SyringeSyringe
Syringe
 
Multipara monitor -Application and Maintenance
Multipara monitor -Application and MaintenanceMultipara monitor -Application and Maintenance
Multipara monitor -Application and Maintenance
 
Blood Pressure Measurement (2011)
Blood Pressure Measurement (2011)Blood Pressure Measurement (2011)
Blood Pressure Measurement (2011)
 
blood pressure
blood pressureblood pressure
blood pressure
 
Infection control
Infection controlInfection control
Infection control
 
Blood pressure
Blood pressureBlood pressure
Blood pressure
 

Similar a Stethoscope and BP apparatus (Sphygmomanometer)

Peripheral pulsations and blood pressure measurement
Peripheral pulsations and blood pressure measurementPeripheral pulsations and blood pressure measurement
Peripheral pulsations and blood pressure measurementabeerabdulkareem
 
Clinical instruments|| PPT||
Clinical instruments|| PPT||Clinical instruments|| PPT||
Clinical instruments|| PPT||Vikash Raj
 
Subjective assignment 2
Subjective assignment 2Subjective assignment 2
Subjective assignment 2amjad hussain
 
Hemostasis during surgery
Hemostasis during surgeryHemostasis during surgery
Hemostasis during surgeryAnkita Singh
 
Non invasive blood pressure monitoring
Non invasive blood pressure monitoringNon invasive blood pressure monitoring
Non invasive blood pressure monitoringrazishahid
 
CHECKING BLOOD PRESSURE.pptx
CHECKING BLOOD PRESSURE.pptxCHECKING BLOOD PRESSURE.pptx
CHECKING BLOOD PRESSURE.pptxJustmiel
 
Blood collection, and Anticoagulants Trial.pptx
Blood collection, and Anticoagulants Trial.pptxBlood collection, and Anticoagulants Trial.pptx
Blood collection, and Anticoagulants Trial.pptxDanAndrewCruzRMTcPhT
 
Peripheral angiography
Peripheral angiographyPeripheral angiography
Peripheral angiographyInosRagan
 
FUNDAMENTAL NURSING -I.ppt
FUNDAMENTAL NURSING -I.pptFUNDAMENTAL NURSING -I.ppt
FUNDAMENTAL NURSING -I.pptBatMan752678
 
VITAL SIGNS.pptx
VITAL SIGNS.pptxVITAL SIGNS.pptx
VITAL SIGNS.pptxSamboGlo
 
Cardiovascular assessment and diagnostic investigations ppt slideshare
Cardiovascular assessment and diagnostic investigations ppt slideshareCardiovascular assessment and diagnostic investigations ppt slideshare
Cardiovascular assessment and diagnostic investigations ppt slidesharesonam
 
RESPIRATORY AND BLOOD PRESSURE ASSESSMENT
RESPIRATORY AND BLOOD PRESSURE ASSESSMENTRESPIRATORY AND BLOOD PRESSURE ASSESSMENT
RESPIRATORY AND BLOOD PRESSURE ASSESSMENTjhonee balmeo
 
Hospital Instruments.ppt
Hospital Instruments.pptHospital Instruments.ppt
Hospital Instruments.pptbkjyotsna
 

Similar a Stethoscope and BP apparatus (Sphygmomanometer) (20)

BLOOD PRESSURE-WPS Office.pptx
BLOOD PRESSURE-WPS Office.pptxBLOOD PRESSURE-WPS Office.pptx
BLOOD PRESSURE-WPS Office.pptx
 
Peripheral pulsations and blood pressure measurement
Peripheral pulsations and blood pressure measurementPeripheral pulsations and blood pressure measurement
Peripheral pulsations and blood pressure measurement
 
Clinical instruments|| PPT||
Clinical instruments|| PPT||Clinical instruments|| PPT||
Clinical instruments|| PPT||
 
Transportation.pptx
Transportation.pptxTransportation.pptx
Transportation.pptx
 
Subjective assignment 2
Subjective assignment 2Subjective assignment 2
Subjective assignment 2
 
VITAL SIGNS.pptx
VITAL SIGNS.pptxVITAL SIGNS.pptx
VITAL SIGNS.pptx
 
Hemostasis during surgery
Hemostasis during surgeryHemostasis during surgery
Hemostasis during surgery
 
Non invasive blood pressure monitoring
Non invasive blood pressure monitoringNon invasive blood pressure monitoring
Non invasive blood pressure monitoring
 
CHECKING BLOOD PRESSURE.pptx
CHECKING BLOOD PRESSURE.pptxCHECKING BLOOD PRESSURE.pptx
CHECKING BLOOD PRESSURE.pptx
 
Blood collection, and Anticoagulants Trial.pptx
Blood collection, and Anticoagulants Trial.pptxBlood collection, and Anticoagulants Trial.pptx
Blood collection, and Anticoagulants Trial.pptx
 
Peripheral angiography
Peripheral angiographyPeripheral angiography
Peripheral angiography
 
FUNDAMENTAL NURSING -I.ppt
FUNDAMENTAL NURSING -I.pptFUNDAMENTAL NURSING -I.ppt
FUNDAMENTAL NURSING -I.ppt
 
VITAL SIGNS.pptx
VITAL SIGNS.pptxVITAL SIGNS.pptx
VITAL SIGNS.pptx
 
BLOOD PRESSURE.ppt
BLOOD PRESSURE.pptBLOOD PRESSURE.ppt
BLOOD PRESSURE.ppt
 
Poster template
Poster templatePoster template
Poster template
 
Cardiovascular assessment and diagnostic investigations ppt slideshare
Cardiovascular assessment and diagnostic investigations ppt slideshareCardiovascular assessment and diagnostic investigations ppt slideshare
Cardiovascular assessment and diagnostic investigations ppt slideshare
 
RESPIRATORY AND BLOOD PRESSURE ASSESSMENT
RESPIRATORY AND BLOOD PRESSURE ASSESSMENTRESPIRATORY AND BLOOD PRESSURE ASSESSMENT
RESPIRATORY AND BLOOD PRESSURE ASSESSMENT
 
A case about Atherosclerosis
A case about AtherosclerosisA case about Atherosclerosis
A case about Atherosclerosis
 
VITAL SIGN ASSESSMEN.ppt
VITAL SIGN ASSESSMEN.pptVITAL SIGN ASSESSMEN.ppt
VITAL SIGN ASSESSMEN.ppt
 
Hospital Instruments.ppt
Hospital Instruments.pptHospital Instruments.ppt
Hospital Instruments.ppt
 

Más de Dr.Sudeesh Shetty

Más de Dr.Sudeesh Shetty (13)

1.importance of rogi roga pareeksha in panchakarma
1.importance of rogi roga pareeksha in panchakarma1.importance of rogi roga pareeksha in panchakarma
1.importance of rogi roga pareeksha in panchakarma
 
Clinical methods by Dr.Sudeesh
Clinical methods by Dr.SudeeshClinical methods by Dr.Sudeesh
Clinical methods by Dr.Sudeesh
 
4. importance and knowledge of dashavidha pariksha
4. importance and knowledge of dashavidha pariksha4. importance and knowledge of dashavidha pariksha
4. importance and knowledge of dashavidha pariksha
 
Ashtasthana pareeksha
Ashtasthana pareekshaAshtasthana pareeksha
Ashtasthana pareeksha
 
Ashtasthana pareeksha
Ashtasthana pareekshaAshtasthana pareeksha
Ashtasthana pareeksha
 
Introduction to Roganidana
Introduction  to RoganidanaIntroduction  to Roganidana
Introduction to Roganidana
 
What is after BAMS
What is after BAMSWhat is after BAMS
What is after BAMS
 
Case Sheet in Ayurveda
Case Sheet in AyurvedaCase Sheet in Ayurveda
Case Sheet in Ayurveda
 
Differential Diagnosis of Icterus/Jaundice
Differential Diagnosis of Icterus/JaundiceDifferential Diagnosis of Icterus/Jaundice
Differential Diagnosis of Icterus/Jaundice
 
STOOL EXAMINATION
STOOL EXAMINATIONSTOOL EXAMINATION
STOOL EXAMINATION
 
Sterilization
SterilizationSterilization
Sterilization
 
Tridosha
TridoshaTridosha
Tridosha
 
Skin Examination
Skin ExaminationSkin Examination
Skin Examination
 

Último

General views of Histopathology and step
General views of Histopathology and stepGeneral views of Histopathology and step
General views of Histopathology and stepobaje godwin sunday
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?TechSoup
 
How to Make a Field read-only in Odoo 17
How to Make a Field read-only in Odoo 17How to Make a Field read-only in Odoo 17
How to Make a Field read-only in Odoo 17Celine George
 
3.21.24 The Origins of Black Power.pptx
3.21.24  The Origins of Black Power.pptx3.21.24  The Origins of Black Power.pptx
3.21.24 The Origins of Black Power.pptxmary850239
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsEugene Lysak
 
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfP4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfYu Kanazawa / Osaka University
 
Practical Research 1 Lesson 9 Scope and delimitation.pptx
Practical Research 1 Lesson 9 Scope and delimitation.pptxPractical Research 1 Lesson 9 Scope and delimitation.pptx
Practical Research 1 Lesson 9 Scope and delimitation.pptxKatherine Villaluna
 
How to Solve Singleton Error in the Odoo 17
How to Solve Singleton Error in the  Odoo 17How to Solve Singleton Error in the  Odoo 17
How to Solve Singleton Error in the Odoo 17Celine George
 
Patterns of Written Texts Across Disciplines.pptx
Patterns of Written Texts Across Disciplines.pptxPatterns of Written Texts Across Disciplines.pptx
Patterns of Written Texts Across Disciplines.pptxMYDA ANGELICA SUAN
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxDr. Asif Anas
 
Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.raviapr7
 
How to Use api.constrains ( ) in Odoo 17
How to Use api.constrains ( ) in Odoo 17How to Use api.constrains ( ) in Odoo 17
How to Use api.constrains ( ) in Odoo 17Celine George
 
How to Add a many2many Relational Field in Odoo 17
How to Add a many2many Relational Field in Odoo 17How to Add a many2many Relational Field in Odoo 17
How to Add a many2many Relational Field in Odoo 17Celine George
 
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptxSandy Millin
 
How to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesHow to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesCeline George
 
HED Office Sohayok Exam Question Solution 2023.pdf
HED Office Sohayok Exam Question Solution 2023.pdfHED Office Sohayok Exam Question Solution 2023.pdf
HED Office Sohayok Exam Question Solution 2023.pdfMohonDas
 
How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17Celine George
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17Celine George
 
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptxPractical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptxKatherine Villaluna
 

Último (20)

General views of Histopathology and step
General views of Histopathology and stepGeneral views of Histopathology and step
General views of Histopathology and step
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?
 
How to Make a Field read-only in Odoo 17
How to Make a Field read-only in Odoo 17How to Make a Field read-only in Odoo 17
How to Make a Field read-only in Odoo 17
 
3.21.24 The Origins of Black Power.pptx
3.21.24  The Origins of Black Power.pptx3.21.24  The Origins of Black Power.pptx
3.21.24 The Origins of Black Power.pptx
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George Wells
 
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfP4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
 
Practical Research 1 Lesson 9 Scope and delimitation.pptx
Practical Research 1 Lesson 9 Scope and delimitation.pptxPractical Research 1 Lesson 9 Scope and delimitation.pptx
Practical Research 1 Lesson 9 Scope and delimitation.pptx
 
How to Solve Singleton Error in the Odoo 17
How to Solve Singleton Error in the  Odoo 17How to Solve Singleton Error in the  Odoo 17
How to Solve Singleton Error in the Odoo 17
 
Patterns of Written Texts Across Disciplines.pptx
Patterns of Written Texts Across Disciplines.pptxPatterns of Written Texts Across Disciplines.pptx
Patterns of Written Texts Across Disciplines.pptx
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptx
 
Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.
 
How to Use api.constrains ( ) in Odoo 17
How to Use api.constrains ( ) in Odoo 17How to Use api.constrains ( ) in Odoo 17
How to Use api.constrains ( ) in Odoo 17
 
How to Add a many2many Relational Field in Odoo 17
How to Add a many2many Relational Field in Odoo 17How to Add a many2many Relational Field in Odoo 17
How to Add a many2many Relational Field in Odoo 17
 
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
2024.03.23 What do successful readers do - Sandy Millin for PARK.pptx
 
How to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesHow to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 Sales
 
Prelims of Kant get Marx 2.0: a general politics quiz
Prelims of Kant get Marx 2.0: a general politics quizPrelims of Kant get Marx 2.0: a general politics quiz
Prelims of Kant get Marx 2.0: a general politics quiz
 
HED Office Sohayok Exam Question Solution 2023.pdf
HED Office Sohayok Exam Question Solution 2023.pdfHED Office Sohayok Exam Question Solution 2023.pdf
HED Office Sohayok Exam Question Solution 2023.pdf
 
How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17
 
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptxPractical Research 1: Lesson 8 Writing the Thesis Statement.pptx
Practical Research 1: Lesson 8 Writing the Thesis Statement.pptx
 

Stethoscope and BP apparatus (Sphygmomanometer)

  • 1. INTRODUCTION TO STETHOSCOPE & SPHYGMOMANOMETER Dr.Sudeesh Shetty, Assistant Professor, Department of Roganidan and Vikriti Vijnana, Mobile:+91-9481818631 Email: drsudeeshshetty@gmail.com drsudeeshshetty@gmail.com 1
  • 2. •The stethoscope (stethophone) is an acoustic medical device for auscultation, or listening to the internal sounds of an animal or human body •Listen to intestines and blood flow in arteries and veins. drsudeeshshetty@gmail.com 2 STETHOSCOPE
  • 5. drsudeeshshetty@gmail.com 5 A French doctor named Rene -Theophile- Hyacinthe-Laennec invented the first stethoscope in 1816. Laennec's Stethoscope
  • 6. drsudeeshshetty@gmail.com 6 • In the early 1850's there was a rush of designs for a new stethoscope that used both ears. • This new 'Bi-aural' or 'Binaural' instrument was felt to be the future of auscultation. Binaural Stethoscope/ Predeccessor to Modern Stethoscope
  • 7. drsudeeshshetty@gmail.com 7  Acoustic stethoscopes are familiar to most people, and operate on the transmission of sound from the chest piece, via air-filled hollow tubes, to the listener's ears Acoustic stethoscopes/Modern Stethoscope
  • 8. drsudeeshshetty@gmail.com 8 Parts: •Ear pieces, binaural pieces, flexible tubing, a stem, and a chestpiece.
  • 10. drsudeeshshetty@gmail.com 10 Principle-Stethoscope works on the principle of multiple reflection of sound. Working- • When a doctor or nurse places a stethoscope diaphragm on a patient's chest, sound waves traveling through the patient's body cause the flat surface of the diaphragm to vibrate. • Those vibrations would travel outward, but because the vibrating object is attached to a tube, the sound waves are channeled in a specific direction. • Each wave bounces, or reflects, off the inside walls of the rubber tube, a process called multiple reflection. • In this way, each wave, in succession, reaches the eartips, or rubber nubs on the ends of the device, and finally the listener's eardrums.
  • 11. drsudeeshshetty@gmail.com 11 Specifications Stethoscope Head Specifications • The size of an adult stethoscope head is 45mm, while a pediatric head is 35mm. • Some stethoscopes have single chest pieces, which mean they are specifically made for either an adult or pediatric patient. However, some have dual heads. • These stethoscopes are designed with both chest pieces and can be used for either adults or children. • The chest piece is made from surgical stainless steel.
  • 12. drsudeeshshetty@gmail.com 12 Tube Specifications • The tubing varies on each model. Stethoscopes with tapered inner bores provide a better sound transmission when listening to the heart or lungs. • If the stethoscope has extra-thick tubing, outside noise is reduced. • You can choose between stethoscopes with a 21-inch single bore flexible tubing or 19-inch two-in-one bi-lumen tubing. • The length of the stethoscope can vary from 27 inches to 29 inches. • It can weigh between 6 ounces and 7.6 ounces. • Tubing can come in black, blue, green, orange, pink and burgundy colors.
  • 13. drsudeeshshetty@gmail.com 13 Type of Stethoscope 1.ACOUSTIC STETHOSCOPE- • This stethoscope-operate on the transmission of sound from the chestpiece, via air-filled hollow tubes, to the listener's ears • Demerit:-Demerit of acoustic stethoscopes was that the sound level is extremely low. • Price of stethoscope:- It is vary from Rs-300 to Rs-20,000.
  • 15. drsudeeshshetty@gmail.com 15 2.Electronic stethoscope • An electronic stethoscope (or) overcomes the low sound levels by electronically amplifying body sounds and may be broadcast through loudspeakers, but in both instances the results are mediocre • The simplest and least effective method of sound detection is achieved by placing a microphone in the chest piece. • can be a wireless device, can be a recording device, and can provide noise reduction, signal enhancement, and both visual and audio output. •Price of stethoscope:- It is vary from Rs-10,000 to Rs-50,000.
  • 20. drsudeeshshetty@gmail.com 20 SPHYGMOMANOMETER • A sphygmomanometer, blood pressure meter, or blood pressure gage (also referred to as a sphygmometer) is a device used to measure blood pressure. • The sphygmomanometer was invented by Samuel Siegfried Karl Ritter von Basch in the year 1881. • Scipione Riva-Rocci introduced a more easily used version in 1896.
  • 21. drsudeeshshetty@gmail.com 21 Construction/Specifications • A sphygmomanometer consists of an inflatable cuff, a measuring unit (the mercury manometer, or aneroid gauge), and a mechanism for inflation which may be a manually operated bulb and valve or a pump operated electrically.
  • 22. drsudeeshshetty@gmail.com 22 Working : • There are two numbers in a blood pressure reading: systolic and diastolic. • When the doctor puts the cuff around your arm and pumps it up, what he/she is doing is cutting off the blood flow with the pressure exerted by the cuff. • As the pressure in the cuff is released, blood starts flowing again and the doctor can hear the flow in the stethoscope. • The number at which blood starts flowing (120) is the measure of the maximum output pressure of the heart (systolic reading). • The doctor continues releasing the pressure on the cuff and listens until there is no sound. • That number (80) indicates the pressure in the system when the heart is relaxed (diastolic reading).
  • 23. drsudeeshshetty@gmail.com 23 • If the numbers are too high, it means that the heart is having to work too hard because of restrictions in the pipes. • Other things that can increase the blood pressure include deposits in the pipes and a loss of elasticity as the blood vessels age. • High blood pressure can cause the heart to fail (from working too hard), or it can cause kidney failure (from too much pressure). For example, a typical reading might be 120/80 or 110/80 mm Hg.
  • 24. drsudeeshshetty@gmail.com 24 1. Should be Portable mercurial type. 2. Should have ISI mark. 3. Should have ON and OFF provision for mercury reservoir. 4. Should have a measuring range from 0 to 300 mmHg. 5. Should be provided with adult arm cuffs of size medium & large and paediatric cuff. 6. The control valve should have a knurled thumb control device. 7. The leak rate should not exceed 10 mm of mercury per minute. 8. The manometer scale markings and graduations should be permanent and clearly visible and filled with pigments. 9. The internal diameter of the manometer glass tube should be 4.1 ± 0.1 mm and the thickness not less than 2 mm. 10. All plastic parts, if any used should not crack, flake, peel or disintegrate in normal use. 11. The inflating rubber bag should be capable of withstanding an internal pressure of 450 mmHg without leaking. 12. The inflating bulb should be soft and should not have any joints or ridges. Technical Specification
  • 25. drsudeeshshetty@gmail.com 25 Aneroid sphygmomanometers : • Mmechanical types with a dial are in common use; they require regular calibration checks, unlike mercury manometers. • Aneroid sphygmomanometers are considered safer than mercury based, although less accurate. • A major cause of departure from calibration is mechanical jarring. • Aneroids mounted on walls or stands are less susceptible to this particular problem. Mercury sphygmomanometers : • They are considered to be the gold standard. • They measure blood pressure directly by observing the height of a column of mercury; errors of calibration cannot occur TYPES
  • 26. drsudeeshshetty@gmail.com 26 Digital: • Digital sphygmomanometers are automated, providing blood pressure reading without needing someone to operate the cuff or listen to the blood flow sounds. • However digital types are less accurate. • Some healthcare providers use digital for screening but use manual sphygmomanometers to validate readings in some situations. Price:-The price of sphygmomanometer vary from Rs-600 to Rs-6000.
  • 27. drsudeeshshetty@gmail.com 27 Blood pressure measurement • Arterial blood pressure is most commonly measured via a sphygmomanometer, which historically used the height of a column of mercury to reflect the circulating pressure. • Blood pressure values are generally reported in millimeters of mercury (mmHg), though aneroid and electronic devices do not contain mercury. For each heartbeat, blood pressure varies between systolic and diastolic pressures. • Systolic pressure is peak pressure in the arteries, which occurs near the end of the cardiac cycle when the ventricles are contracting. Diastolic pressure is minimum pressure in the arteries, which occurs near the beginning of the cardiac cycle when the ventricles are filled with blood.
  • 28. drsudeeshshetty@gmail.com 28 • Systolic and diastolic arterial blood pressures are not static but undergo natural variations from one heartbeat to another and throughout the day (in a circadian rhythm). • They also change in response to stress, nutritional factors, drugs, disease, exercise, and momentarily from standing up. • Sometimes the variations are large. • Along with body temperature, respiratory rate, and pulse rate, blood pressure is one of the four main vital signs routinely monitored by medical professionals and healthcare providers.
  • 29. drsudeeshshetty@gmail.com 29 Location of measurement • The standard location for blood pressure measurement is the brachial artery. • Monitors that measure pressure at the wrist and fingers have become popular, but it is important to realize that systolic and diastolic pressures vary substantially in different parts of the arterial tree with systolic pressure increasing in more distal arteries, and diastolic pressure decreasing.
  • 30. 1.INVASIVE 2.NONINVASIVE drsudeeshshetty@gmail.com 30 Basic techniques of blood pressure measurement:
  • 31. drsudeeshshetty@gmail.com 31 Non-invasive • The non-invasive auscultatory and oscillometric measurements are simpler and quicker than invasive measurements, require less expertise, have virtually no complications, are less unpleasant and less painful for the patient. • However, non-invasive methods may yield somewhat lower accuracy and small systematic differences in numerical results. • Non-invasive measurement methods are more commonly used for routine examinations and monitoring. 1.Palpation/Manual /Placatory method • A minimum systolic value can be roughly estimated by palpation, most often used in emergency situations, but should be used with caution • A more accurate value of systolic blood pressure can be obtained with a sphygmomanometer and palpating the radial pulse
  • 32. drsudeeshshetty@gmail.com 32 2.Auscultatory • The auscultatory method (from the Latin word for "listening") uses a stethoscope and a sphygmomanometer • Listening with the stethoscope to the brachial artery at the antecubital area of the elbow, the examiner slowly releases the pressure in the cuff. • When blood just starts to flow in the artery, the turbulent flow creates a "whooshing" or pounding (first Korotkoff sound). • The pressure at which this sound is first heard is the systolic blood pressure. • The cuff pressure is further released until no sound can be heard (fifth Korotkoff sound), at the diastolic arterial pressure. • The auscultatory method is the predominant method of clinical measurement
  • 33. drsudeeshshetty@gmail.com 33 • Although the auscultatory method using mercury sphygmomanometer is regarded as the ‘gold standard’ for office blood pressure measurement, widespread implementation of the ban in use of mercury sphygmomanometers continues to diminish the role of this technique. • The situation is made worse by the fact that existing aneroid manometers, which use this technique, are less accurate and often need frequent calibration. • New devices known, as “hybrid” sphygmomanometers, have been developed as replacement for mercury devices. • Basically, these devices combine the features of both electronic and auscultatory devices such that the mercury column is replaced by an electronic pressure gauge, similar to oscillometric devices, but the blood pressure is taken in the same manner as a mercury or aneroid device, by an observer using a stethoscope and listening for the Korotkoff sounds
  • 35. drsudeeshshetty@gmail.com 35 3. The oscillometric technique • The oscillometric method was first demonstrated in 1876 and involves the observation of oscillations in the sphygmomanometer cuff pressure which are caused by the oscillations of blood flow, i.e., the pulse. • The electronic version of this method is sometimes used in long-term measurements and general practice. • It uses a sphygmomanometer cuff, like the auscultatory method, but with an electronic pressure sensor (transducer) to observe cuff pressure oscillations, electronics to automatically interpret them, and automatic inflation and deflation of the cuff. • The pressure sensor should be calibrated periodically to maintain accuracy.
  • 36. drsudeeshshetty@gmail.com 36 This was first demonstrated by Marey in 1876,and it was subsequently shown that when the oscillations of pressure in a sphygmomanometer cuff are recorded during gradual deflation, the point of maximal oscillation corresponds to the mean intra- arterial pressure.The oscillations begin at approximately systolic pressure and continue below diastolic, so that systolic and diastolic pressure can only be estimated indirectly according to some empirically derived algorithm. This method is advantageous in that no transducer need be placed over the brachial artery, and it is less susceptible to external noise (but not to low frequency mechanical vibration), and that the cuff can be removed and replaced by the patient during ambulatory monitoring, for example, to take a shower. The main disadvantage is that such recorders do not work well during physical activity when there may be considerable movement artifact. The oscillometric technique has been used successfully in ambulatory blood pressure monitors and home monitors. It should be pointed out that different brands of oscillometric recorders use different algorithms, and there is no generic oscillometric technique. Comparisons of several different commercial models with intra-arterial and Korotkoff sound measurements, however, have shown generally good agreement.
  • 37. drsudeeshshetty@gmail.com 37 4.Ultrasound techniques Devices incorporating this technique use an ultrasound transmitter and receiver placed over the brachial artery under a sphygmomanometer cuff. As the cuff is deflated, the movement of the arterial wall at systolic pressure causes a Doppler phase shift in the reflected ultrasound, and diastolic pressure is recorded as the point at which diminution of arterial motion occurs. Another variation of this method detects the onset of blood flow at systolic pressure, which has been found to be of particular value for measuring pressure in infants and children. In patients with very faint Korotkoff sounds (for example those with muscular atrophy) placing a Doppler probe over the brachial artery may help to detect the systolic pressure, and the same technique can be used for measuring the ankle-brachial index, in which the systolic pressures in the brachial artery and the posterior tibial artery are compared, to obtain an index of peripheral arterial disease.
  • 38. drsudeeshshetty@gmail.com 38 5.The finger cuff method of Penaz This interesting method was first developed by Penaz and works on the principle of the “unloaded arterial wall.” Arterial pulsation in a finger is detected by a photo- plethysmograph under a pressure cuff. The output of the plethysmograph is used to drive a servo-loop, which rapidly changes the cuff pressure to keep the output constant, so that the artery is held in a partially opened state. The oscillations of pressure in the cuff are measured and have been found to resemble the intra-arterial pressure wave in most subjects This method gives an accurate estimate of the changes of systolic and diastolic pressure when compared to brachial artery pressures; the cuff can be kept inflated for up to 2 hours. It is now commercially available as the Finometer and Portapres recorders and has been validated in several studies against intra-arterial pressures.The Portapres enables readings to be taken over 24 hours while the subjects are ambulatory, although it is somewhat cumbersome.
  • 39. drsudeeshshetty@gmail.com 39 Invasive Method • There are a variety of invasive vascular pressure monitors for trauma, critical care, and operating room applications. • These include single pressure, dual pressure, and multi-parameter (i.e. pressure / temperature). • The monitors can be used for measurement and follow-up of arterial, central venous, pulmonary arterial, left atrial, right atrial, femoral arterial, umbilical venous, umbilical arterial, and intracranial pressures.
  • 41. drsudeeshshetty@gmail.com 41 Arterial blood pressure is most accurately measured invasively through an arterial line. Invasive arterial pressure measurement with intravascular cannulae involves direct measurement of arterial pressure by placing a cannula needle in an artery (usually radial, femoral, dorsalis pedis or brachial). The cannula is inserted either via palpation or with the use of ultrasound guidance.The cannula must be connected to a sterile, fluid-filled system, which is connected to an electronic pressure transducer. The advantage of this system is that pressure is constantly monitored beat-by-beat, and a waveform (a graph of pressure against time) can be displayed. This invasive technique is regularly employed in human and veterinary intensive care medicine, anesthesiology, and for research purposes. Cannulation for invasive vascular pressure monitoring is infrequently associated with complications such as thrombosis, infection, and bleeding. Patients with invasive arterial monitoring require very close supervision, as there is a danger of severe bleeding if the line becomes disconnected. It is generally reserved for patients where rapid variations in arterial pressure are anticipate
  • 42. drsudeeshshetty@gmail.com 42 Technical issues with measurement from the arm • There are important potential sources of error with measurements from the upper arm, which are discussed in the following sections. Effects of posture • There is no consensus as to whether blood pressure should be routinely measured while seated or supine, although most guidelines recommend sitting. • In a survey of 245 subjects of different ages, Netea et al found that systolic pressures were the same in both positions, but there was a systematic age- related discrepancy for diastolic pressure such that at the age of 30 the sitting diastolic was about 10 mm Hg higher than the supine reading, whereas at the age of 70 the difference was only 2 mm Hg.
  • 43. drsudeeshshetty@gmail.com 43 Body position • Blood pressure measurements are also influenced by the position of the arm. • As shown in, there is a progressive increase in the pressure of about 5 to 6 mm Hg as the arm is moved down from the horizontal to vertical position. • These changes are exactly what would be expected from the changes of hydrostatic pressure. • It is also important that the patient’s back be supported during the measurement; if the patient is sitting bolt upright the diastolic pressure may be up to 6.5 mm Hg higher than if sitting back.
  • 44. drsudeeshshetty@gmail.com 44 Ambulatory monitors First developed almost 40 years ago, ambulatory blood pressure monitoring is only now beginning to find acceptance as a clinically useful technique. Recent technologic advances have led to the introduction of monitors that are small and relatively quiet and that can take up to 100 readings of blood pressure over 24 hours while patients go about their normal activities. They are reasonably accurate while the patient is at rest but less so during physical activity.
  • 46. drsudeeshshetty@gmail.com 46 Thresholds for intervention BP ≥ 220/120 mmHg: treat immediately BP >180-189/110/119 mmHg: confirm over 1-2 weeks, then treat BP 160-179/100-109 mmHg: with CVD complications: confirm over 3-4 weeks, then treat BP 140-159/90-99 mmHg: with CVD risk confirm over 12 weeks, then treat.
  • 47. drsudeeshshetty@gmail.com 47 Blood pressure measurement sources of error Errors due to manometer Errors due to cuff Errors due to the observer Errors due to the patient.
  • 48. drsudeeshshetty@gmail.com 48 Manometers – automatic disadvantages Inadequate choice of cuff sizes Large cuffs are long enough but too deep Need for the equivalent of the ‘alternative adult cuff’ only available with the mercury manometer.
  • 49. drsudeeshshetty@gmail.com 49 BP measurement Three or more readings, separated by 1 minute Discard first reading and average last two If large difference take further readings.
  • 50. drsudeeshshetty@gmail.com 50 BP measurement -cuffs Cuff too small or too big Normal cuff too small for 15% of patients Cuff not level with the heart Leaky rubber tubing or bladder Faulty inflation/deflation device Applies to mercury manometers only.
  • 51. drsudeeshshetty@gmail.com 51 Cuff sizes Type Size Suitability Adult 12cm by 23cm for smaller arms Alternative cuff 12cm by 36cm will cover 95% arms Large adult 15cm by 36cm Often too wide for ‘fat’ arms
  • 52. drsudeeshshetty@gmail.com 52 Cuff Arm circumference (cm) Bladder width (cm) Bladder length (cm) Newborn <6 3 6 Infant 6–15 5 15 Child 16–21 8 21 Small adult 22–26 10 24 Adult 27–34 13 30 Large adult 35–44 16 38 Adult thigh 45–52 20 42
  • 53. drsudeeshshetty@gmail.com 53 6% of hypertensives can have as much as a 10 mmHg difference between arms If BP higher in one arm than the other, this arm must be used from then on Document this in records so that everyone uses the same arm. Which arm?
  • 54. drsudeeshshetty@gmail.com 54 Technique Patient seated and relaxed, not talking, legs uncrossed Tight arm clothing removed Correct cuff size Arm supported with cuff horizontal with heart Inform patient of discomfort and that several measurements will be taken Mercury manometer on firm and level surface at eye level Locate brachial or radial pulse.
  • 55. drsudeeshshetty@gmail.com 55 Technique – cont’d Place stethoscope gently over brachial artery Inflate mercury rapidly, 30 mmHg above occlusion of pulse Deflate very slowly, 2 mmHg per second Record first of regular sounds (systolic BP) Record diastolic as disappearance of sound Record measurements to the nearest 2 mmHg Repeat twice more and average last two.
  • 56. drsudeeshshetty@gmail.com 56 BP measurement – observer Mercury column not level with the eyes Failure to hear the Korotkoff sounds Wrong diastolic endpoint (K4 or K5) Subjective detection of Korotkoff sounds Rapid cuff deflation Single one off reading.
  • 57. drsudeeshshetty@gmail.com 57 Stethoscope Good quality Short tubing Well fitting ear pieces (cleaned regularly) Place gently over the brachial artery Avoid touching the cuff and tubing.
  • 58. drsudeeshshetty@gmail.com 58 Posture Routine - seated Standing in patients with symptoms or diabetic (diabetic nephropathy) and the elderly Supine position unnecessary, inconvenient and cuff position often below the heart.
  • 59. drsudeeshshetty@gmail.com 59 BP measurement – patient Anxiety and unfamiliarity Animated discussion about the latest news Ambient temperature Full bladder! Postural hypotension Difference between arms.
  • 60. drsudeeshshetty@gmail.com 60 Patient Consent is taken as read when patient rolls up sleeve Explain the procedure, that it may be a little uncomfortable and that several readings will be taken Seated, relaxed, not speaking Tight arm clothing removed Arm supported (not hyper extended)with cuff level with the heart.
  • 61. drsudeeshshetty@gmail.com 61 Explanation to the patient Tell the patient their blood pressure reading Write BP down – use co-operation cards Give relevant leaflets/booklets on life style issues (not too many at a time) Reassure patient that this is a risk factor not a disease (unless left untreated) Do not lose to follow-up.
  • 62. drsudeeshshetty@gmail.com 62 ‘White coat’ hypertension Effective method of diagnosing a rise in blood pressure associated with having blood pressure measured Maybe from anxiety 10-20% of subjects labelled ‘hypertensive’ may have ‘white coat’ effect.