11. Reynold’s number
RN=ρ*v*L/μ
ρ: density of the blood
L: characteristic dimension of the vessel, in this case
diameter
V: mean velocity of the blood
μ: viscosity of blood
<2300-------laminar flow
>4000-------turbulent flow
17. Korotkoff Sounds
First Phase
A clear tapping sound; onset of the sound for two consecutive
beats is considered systolic
Second Phase
The tapping sound followed by a murmur
Third Phase
A loud crisp tapping sound
Fourth Phase
Abrupt, distinct muffling of sound, gradually decreasing in
intensity
Fifth Phase
The disappearance of sound, is considered diastolic blood
pressure- two points below the last sound heard
25. Classification of blood pressure for adults
Category systolic, mmHg diastolic, mmHg
Hypotension < 90 < 60
Normal 90 - 119 60 - 79
Prehypertension 120 – 139 or 80 – 89
Stage 1 Hypertension 140 – 159 or 90 – 99
Stage 2 Hypertension 160 - 179 or 100 - 109
Hypertensive Crisis ≥ 180 or ≥ 110
26. Steps for Measuring
Blood Pressure
Seated for 5 minutes
Patient Position
Expose Upper arm
Center of upper arm at heart level
27. Steps for measuring
Cuff applied 1 inch above crease at elbow
Locate brachial artery
Palpate radial pulse
Inflate cuff until pulse disappears
28. Steps for measuring
Let air out
Place stethoscope on brachial artery
Pump up cuff to 20-30 above point of obliteration
Let air out at 2 mmHg per second
Repeat for the other hand
Compare R & L BP
29. Steps for measuring
Note 1st and 5th Korotkoff sounds
Chart:
#’s
Position
Arm used
Cuff size
Normal, pre-hypertension, stage 1 hypertension, or
stage 2 hypertension
Recommendations of what’s next
30. Orthostatic hypotension
BP in supine position
BP on stand position
Every 2min
Decrease greater than 20/10
33. Effects of gravity on arterial and venous pressures.
Each cm of distance produces a 0.77 mmHg change.
0 100 mm Hg
190 mm Hg
Sphincters protect
capillaries
Veins Arteries
VENOUS PUMP keeps PV < 25 mm Hg
35. What would you tell a person
about their blood
pressure reading?
Definition of Blood Pressure
Numerical Value
Blood Pressure Category
When to Recheck
Medications if Necessary
Lifestyle Modifications
36. Hyperemia
Definition:
Excessive accumulation of blood in a part of the body
Passive, by obstruction of the blood flow
Active: relaxation of arteries
Reactive, in response to an temporary interruption
37. Reactive hyperemia
1. Rise a hand, inflate up to 180mmhg
After 4min open the cuff
2. Inflate the cuff up to 70mmhg
After 4min open the cuff
3. Use a couple of cuffs for both hands
Rise a hand, inflate up to 180mmhg
After 4min deflate down to 70mmhg and inflate the
other hand up to 70mmhg
38. Following can cause sounds to be
heard down to zero
Physiologic
a. Childhood
b. Pregnancy
c. Vigorous exercise
Pathologic
a. Hyperthyroidism
b. Hyperactivity of
adrenal
c. Anemia
d. Heavy pressure on
the stethoscope
39. A cuff with a bladder too small for
the patients arm
will result
in:
a. An inaccurately high reading
b. An inaccurately low reading
c. Sounds heard down to zero mmHg