This document discusses blood pressure, including an overview, variations, determinants, regulation, and measurement. It defines systolic and diastolic blood pressure and other related terms. The key factors that determine and regulate blood pressure are described, including cardiac output, peripheral resistance, blood volume, hormones, the nervous system, kidneys, and local mechanisms. Methods for measuring blood pressure are outlined, including palpatory, auscultatory, and oscillometric techniques. Special considerations for taking blood pressure in certain populations are also noted.

1. BLOOD PRESSURE AND ITS
APPLIED PHYSIOLOGY
Dr. Soham Prajapati
1st Year PG,
Dept. of Prosthodontics
& Maxillofacial Prosthesis
Including Oral Implantology
1

2. Contents
• Introduction
• Blood Pressure Overview
• Variations
• Determinants of arterial blood
pressure – factors maintaining
arterial blood pressure
• Regulation of Arterial Blood
Pressure
2

3. • Measurement of Arterial Blood Pressure
• Blood pressure recording in special situations
• Conclusion
• References
3

4. • Local Anesthesia With Vasoconstriction
• White Coat Hypertension
• General Principles of Hypertensive Therapy
• Hypotension
• Orthostatic Hypotension
• Supine Hypotensive Syndrome
• Hypertension and Implants
• Conclusion
• References
4

5. Introduction
• Blood is a connective tissue in fluid form.
• It is considered as
– Fluid of life
– Fluid of growth
– Fluid of health
scanning electron microscope (SEM) image
of a normal red blood cell, a platelet, and a
white blood cell.
5

6. Blood Pressure
• Blood pressure (BP), sometimes referred to as
arterial blood pressure , is the pressure
exerted by circulating blood upon the walls of
blood vessels, and is one of the principal vital
signs.
• Blood pressure consists of three types:
– Arterial pressure
– Venous pressure
– Capillary Pressure
6

7. Properties of Blood
1.Colour :- Arterial blood is scarlet red.
Venous blood is purple red.
2.Volume:- Average blood volume is 5 L.
New born Baby = 450 ml.
Females :- 4.5 L
3.Reaction and pH: Slightly Alkaline and its pH is
7.4 in normal conditions.
7

8. • Viscosity:- Five times more viscous than water
• Specific Gravity:- Total Blood : 1.052 to 1.061
Blood Cells : 1.092 to 1.101
Plasma : 1.022 to 1.026
8

9. 1.Arterial Blood Pressure is defined as the lateral
pressure exerted by the contained column of
blood on the wall of arteries.
9

10. 2.Venous Pressure is the pressure exerted by the
contained blood in the veins. The pressure in
vena cava and right atrium is called central
venous pressure. And the pressure in peripheral
veins is called peripheral venous pressure.
10

11. 3. Capillary (Hydrostatic) Pressure is the
pressure exerted by the blood contained in
capillary.
11

12. • SYSTOLIC BLOOD PRESSURE is defined as
maximum pressure exerted in the arteries
during systole of the heart.
• DIASTOLIC BLOOD PRESSURE is defined as the
minimum pressure in the arteries during
diastole of the heart.
12

13. 13

14. • PULSE PRESSURE is the difference between
the systolic pressure and diastolic pressure.
Normally it is 40 mm of Hg.
14

15. • MEAN ARTERIAL BLOOD PRESSURE is the
average pressure existing in the arteries. It is
the arithmetic mean of systolic and diastolic
pressures.
• Calculated as DIASTOLIC PRESSURE + 1/3 of
PULSE PRESSURE.
• Normally
it is 93 mm
of Hg (80 + 13).
15

16. • SBP: systolic blood
pressure; DBP:
diastolic blood
pressure.
• Table 1.
Classification of
blood pressure in
subjects over 18
years of age
(National Committee
on Prevention,
Detection,
Evaluation, and
Treatment of High
Blood Pressure)
• e98
• J Clin Exp Dent.
2011;3(2):e97-105.
CLASSIFICATION OF BLOOD PRESSURE IN
ADULTS
Classification of blood
pressure
SBP
(mmHg)
DBP
(mmHg)
Normal
< 120
< 80
Prehypertension
120-139
80-89
AH
T
Stage 1
140-159
90-99
Stage 2
≥ 160
≥ 100
16

17. Variations
17

18. Physiological Variation• Age:- Increases as age advances
Systolic pressure
NEW BORN – 40 mm of Hg
AFTER 15 DAYS – 70 mm of Hg
AFTER 1 MONTH – 90 mm of Hg
AT PUBERTY –120 mm of Hg
50 YEARS – 140 mm of Hg
Diastolic pressure
AT PUBERTY –80 mm of Hg
50 YEARS – 85 mm of Hg
18

19. • Gender: In females up to the period of
menopause, the arterial pressure is low (up to
5 mm of Hg) as compared to males of same
age. After menopause, the pressure in females
become equal to that in males of same age.
19

20. • Body Built: The pressure is more in obese persons
than in lean patients.
• Diurnal Variations: In early morning, the pressure
is slightly low. It gradually increases and reaches
the maximum at noon. It becomes low in
evening. 20

21. • After Meals: It is increases for few hours due
to increase in cardiac output.
• During Sleep: Reduces 15-20 mm of Hg during
sleep. However, it increases slightly during
sleep associated with dreams.
21

22. • Emotional Conditions: During anxiety or
excitement, the blood pressure increases due to
release of adrenaline.
• After Exercise: After moderate exercise, systolic
pressure increases by 20- 30 mm of Hg above the
basal level due to increase in force of contraction
and stroke volume. Normally, diastolic is not
affected.
22

23. • Pathological variation:
-Renal Artery Stenosis
-Pheochromocytoma
-Preclamptic toxemia
• Drug induced:
-Stimulants (sympathetic) ex:-adrenaline,
noradrenalin, phenyl epinephrine, >s B P
-Relaxants (of vascular smooth muscle) < s B P
-Diuretics <s B P( due to reduction in blood volume )
23

24. DETERMINANTS OF ARTERIAL BLOOD
PRESSURE – FACTORS MAINTAINING
ARTERIAL BLOOD PRESSURE
– CENTRAL FACTORS (PERTAINING TO THE HEART)
– PERIPHERAL FACTORS (PERTAINING TO BLOOD &
BLOOD VESSELS)
24

25. • IT INCLUDES:
– Cardiac output
– Heart Rate
Cardiac output : Systolic blood pressure is directly
proportional to cardiac output. Increases during
muscular exercise and emotional condition and rise
in systolic pressure. In myocardial infarction, the
cardiac output decreases and fall in systolic
pressure.
CENTRAL FACTORS
25

26. • Heart Rate: Cardiac output is the product of
stroke volume and heart rate. And in turn
depends upon blood volume, venous return,
heart rate and force of contraction.
• Moderate changes in heart rate do not affect
arterial blood pressure much. However, marked
alteration in the heart rate affects the blood
pressure by altering diastolic period and stroke
volume.
26

27. Peripheral Factors
• It includes:
– Peripheral resistance
– Blood volume
– Venous return
– Elasticity of blood vessels
– Velocity of blood flow
– Diameter of blood vessels
– Viscosity of blood
27

28. Regulation of Arterial Blood Pressure
• Arterial blood pressure varies even under
physiological conditions. However,
immediately it is brought back to normal level
because of the presence of well organized
regulatory mechanisms in the body.
28

29. 29
Regulation of
Blood Pressure
Nervous
Mechanism
By Vasomotor
center and
impulses from
periphery
Renal
Mechanism
By regulation
of ECF volume
and renin-
angiotensin
mechanism
Hormonal
Mechanism
By
vasoconstriction
and vasodilator
hormones
Local
Mechanism
By local
vasoconstrictors
and
vasodialators

30. Nervous Mechanism
• Rapid among all mechanisms.
• Although quick in action, it operates only for a
short period of time and then it adapts to the
new pressure. Hence, it is called short term
regulation.
• Operates through the vasomotor system.
30

31. 31
REGULATION OF BLOOD PRESSURE BY BARORECEPTORS
INCREASE IN
BLOOD PRESSURE
BARORECEPTORS
IMPULSES VIA
IX AND X
CRANIAL
NERVES
NORMAL BLOOD PRESSURE
DIALATION OF BLOOD
VESSELS
BRADYCARDIA AND
REDUCTION IN
CARDIAC OUTPUT
INCREASE IN
VASOMOTOR TONE INCREASE IN VAGAL TONE
INHIBITION OF
VASOCONSTRICTION
AREA
STIMULATION OF
VASODIALATOR AREA
NUCLEUS OF TRACTUS
SOLITARIUS
STIMULATION

32. Renal Mechanism
• Kidney plays an important role.
• When Blood Pressure alters slowly in several
days/months/years, the neural mechanism
adapts to the altered pressure and looses the
sensitivity for the changes.
• Kidney regulates blood pressure by two ways:
– By regulation of ECF volume
– Through renin-angiotensin mechanism
32

33. 33
REGULATION OF BLOOD PRESSURE BY RENIN ANGIOTNESIN MECHANISM
DECREASE IN
BLOOD PRESSURE
JUXTAGLOMERULAR
APPARATUS
RENIN
NORMAL BLOOD PRESSURE
VASOCONSTRICTION
INCREASE IN BLOOD
VOLUME
INCREASE IN ECF
VOLUME
REABSORTION OF
WATER AND SODIUM
KIDNEY
STIMULATION
ALDOSTERONE
ANGIOTENS
INOGEN
ANGIOTENS
IN I
ANGIOTENS
IN II
ADRENAL CORTEX
CONVERTING
ENZYME

34. Hormonal Mechanism
• Hormones, which increase the blood pressure:
– Adrenaline
– Noradrenaline
– Thyroxine
– Aldosterone
– Vasopressin
– Angiotensin
– Serotonin
34

35. Hormonal Mechanism
• Hormones, which decrease the blood pressure
– VIP- Vasoactive Intestinal Polypeptide
– Bradykinin
– Prostaglandin
– Histamine
– Acetylcholine
– Atrial natriuretic peptide
– Brain natriuretic peptide
– C-type natriuretic peptide
35

36. Local Mechanism
• Local substances regulate the blood pressure by
vasoconstriction or vasodilation.
• Vasoconstrictor substances are endothelins (ET).
• Vasodilators are carbon dioxide, hydrogen ions,
lactate, adenosine and nitric oxide.
36

37. Measurement of Arterial Blood Pressure
• Blood Pressure was first measured in horse in
1733.
• In 1847, Ludwig placed a float on the top of
mercury column and made continuous
recording possible.
• Measured by two methods:
– Direct method
– Indirect method
37

38. Direct Method: Employed only in animals
38

39. Indirect Method
• Apparatus: The apparatus
used to measure blood
pressure is called
sphygmomanometer. Along
with this, stethoscope is also
necessary to measure blood
pressure.
Consists of:
-Inflatable cuffs
-Pressure gauge or
mercury manometer ,has
long and short arm each
-Hand pump
Stethoscope:
Consists of End piece;
Connect by tubes to Ear piece
39

40. • Principle:
– When an external pressure is applied over the
artery, the blood flow through it is obstructed.
And the pressure required to cause occlusion of
blood flow indicates the pressure inside the
vessel.
40

41. – Brachial artery is usually chosen!!!!(convenience).
– The arm cuff is tied around the upper arm above
the cubital fossa.
41

42. • Cuff should not be too tight or too loose.
• Measured by three methods:
– Palpatory method
– Auscultatory method
– Oscillatory method
42

43. Palpatory Method
• First, the radial pulse is felt.
• While feeling the pulse, the pressure is increased
in the cuff by inflating air into it, with the help of
hand cuff.
• When the radial pulse
disappears,
the pressure is further
Increased by
about 20 mm Hg.
43

44. • Then, the pressure in the cuff is slowly
reduced by releasing the valve of hand pump.
• Pulse is noted when the pulse reappears.
• This pressure indicates systolic pressure.
• DISADVANTAGE: DIASTOLIC PRESSURE
CANNOT BE MEASURED.
44

45. AUSCULTATORY METHOD
• MOST ACCURATE METHOD
• After determining the systolic pressure in
Palpatory method, the pressure in the cuff is
raised by about 20 mm Hg above the level so
that, the brachial artery is occluded due to
compression.
45

46. • Now the chest piece of the stethoscope is
placed over the cubital fossa, and the pressure
is released from the cuff.
• While doing so, series of sounds are heard
through the stethoscope. These sounds are
called Korotkoff’s sounds.
• While reducing the pressure, Korotkoff’s
sounds appear in five phases.
46

47. Korotkoff’s Sounds
• Phase 1: Appearance of tap sound, this marks the
systolic BP
• Phase 2: Sound takes up the murmuring quality,
Auscultatory gap may appear in this phase.
• Phase 3: Sound becomes very loud and gauging in
quality.
• Phase 4: Sound suddenly becomes muffled.
• Phase 5: All sounds disappear, DBP recorded here.
47

48. • Thus, in Auscultatory method, the appearance
of the clear tapping sound during the first
phase indicates systolic pressure and the
disappearance of the muffling sound shows
diastolic pressure.
48

49. Oscillatory Method
• Inaccurate for routine clinical practice.
• By connecting the manometer to an
appropriate recording device the oscillation of
the mercury column can be recorded
graphically.
49

50. NOWDAYS
• Automatic blood pressure instrument is
AVAILABLE.
• The instrument has a microprocessor- driven
air pump which automatically inflates the air
cuff and a fixed pressure valve.
• Then, it records the pressure oscillation
pattern during a stepwise deflation.
50

51. • The sensors in the instrument detect the
oscillatory waves and determine the systolic
and diastolic pressure. Also pulse rate is
measured.
• The microprocessor controlled blood pressure
monitors that are fixed around the wrist or
finger are also available.
51

52. 52

53. 53

54. 54

55. EFFECT OF THE BODY POSITION
• BP measurement is most commonly made in
either the sitting or supine position, but the
two positions give different measurements.
• It is widely accepted that diastolic pressure
measured while sitting is higher than when
measured supine (by about 5 mm Hg),
although there is less agreement about
systolic pressure.
55

56. • When the arm position is meticulously
adjusted so that the cuff is at the level of the
right atrium in both positions, the systolic
pressure has been reported to be 8 mm Hg
higher in the supine than the upright position.
• If the back is not supported, the diastolic
pressure may be increased by 6 mm Hg.
• Crossing the leg may raise systolic pressure by
2 to 8 mm Hg.
56

57. Effects of Arm Position
• Major influence, when BP is measured.
• If the upper arm is below the level of the right
atrium (when the arm is hanging down while
in the sitting position), the readings will be too
high.
• If the arm is above the heart level, the
readings will be too low.
57

58. • This is due to effect of the hydrostatic
pressure.
• Other physiologic factor is muscular tension.
• If the arm is held up by the patient(being
unsupported) , the isometric exercise will raise
the pressure.
58

59. Blood Pressure recording in Special
Situations
• Elderly Patients
– BP Should be measured while seated, 2 or more
times at each visit, and the readings should be
averaged.
– Also measured in standing position routinely,
because may have postural hypotension.
– Hypotension is more common in diabetic
patients.
– It can help elucidate some symptoms such as
episodic faintness and nocturnal dyspnea.
59

60. Obese Patients
• A Longer and wider cuff is needed for adequate
compression of brachial artery with a very large
arm.
• In the rare patients with an arm
circumference>50 cm, when even a thigh cuff
cannot be fitted over the arm, it is recommended
that the practioner wrap an appropriately sized
cuff around the patient’s forearm, support it at
heart level, and fell for the appearance of the
radial artery pulse at the wrist.
60

61. Children
• BP is most conveniently measured in children
by auscultation with a standard mercury
sphygmomanometer.
• The stethoscopes is placed in the same way as
an adult.
• Should be conducted after 3 to 5 minutes of
rest.
• Measured for 2 times and average is
calculated.
61

62. Pregnant Women
• Hypertension is most common medical
disorder of pregnancy and occurs in 10-12% of
all pregnancies.
• Measured in seated position.
• Measurement of BP in left recumbence, on
the left arm , does not differ substantially
from the BP that is recorded in the sitting
position.
62

63. Conclusion
• Hypertensive is usually a symptomatic and is
the major risk factor for coronary heart
disease and cerebrovascular accidents.
• Patients with essential hypertension are more
susceptible to 3 times as much coronary
disease, 4 times as much cardiac failure and 7
times as many strokes as normotensive
patients
63

64. References
• Essential of Medical Physiology, K
Sembulingam and P Sembulingam, 4th
Edition.
• Textbook Of Medical Physiology, Guyton and
Hall, 11th Edition.
• Principles and Practice of Medicine,Davidson,
20th Edition.
64

65. • Contemporary Implant Dentistry,Misch, 3rd
Editition.
• Essential of Medical Physiology, K. D. Tripathy, 6th
Edition.
• Dental considerations in patients with heart
disease Marta Cruz-Pamplona 1 , Yolanda
Jimenez-Soriano 2 , Maria Gracia Sarrión-Pérez 1
• Infective endocarditis prophylaxis and the current
AHA, BSAC, NICE and Australian guidelines .
journa! Oif the Irish Dental Association 2008; 54
(6): 264-270.
65

66. • Classification of blood pressure in subjects over 18 years of
age (National Committee on Prevention, Detection,
Evaluation, and Treatment of High Blood Pressure), e98, J
Clin Exp Dent. 2011;3(2):e97-105.
• Banaś T, Godula Z, Herman R (2004). "[Aortocaval
compression syndrome as an explanation of sudden
intrauterine death of mature twins at term. Case report]".
Ginekol Pol 75 (8): 633–7.
• SUPINE HYPOTENSIVE SYNDROME IN DENTAL TREATMENT,
Dr. Kapil Sharma, Dr. Jaya Pamboo Department and
institution: Assistant Professor Dept of oral and
maxillofacial surgery Jodhpur Dental College
66

67. • Recommendations for Blood Pressure
Measurement in Humans and Experimental
Animals : Part 1: Blood Pressure Measurement in
Humans: A Statement for Professionals From the
Subcommittee of Professional and Public
Education of the American Heart. Association
Council on High Blood Pressure Research .Thomas
G. Pickering, John E. Hall, Lawrence J. Appel,
Bonita E. Falkner, John Graves, Martha N. Hill,
Daniel W. Jones, Theodore Kurtz, Sheldon G.
Sheps and Edward J. Roccella
67

68. 68
Thank You