Disorders of Blood Pressure Regulation

Chapter 31 Disorders of Blood Pressure Regulation

C. Pulse pressure: Difference between systolic and diastolic pressure

D. mean arterial pressure - average pressure in arterial system during both

ventricular contraction and relaxation.

= 1/3 of pulse pressure (PP) added to diastolic pressure (D) [there are other formula].

II. Hypertension – contributes to about 1 in 6 deaths in the U.S.

A. most common cardiovascular problem in US (see Table 31.1 on p. 774)

1. normal: systolic below 120 and diastolic less than 80,

2. pre-hypertension: systolic between 120-139 and/or diastolic between 80-89,

3. HTN-HBP stage one: systolic 140-159 and/or diastolic between 90-99,

4. HTN-HBP stage two: systolic 160 or above, and/or a diastolic 100 or higher

B. Primary (essential) hypertension 90-95% of all cases of chronic HBP

1. cause unknown several theories [about 1 in 6 in U.S. have HBP/HTN]

a. hemodynamic, neural, renal and hormonal mechanism, (natriuretic

hormone)

2. Symptoms: typically asymptomatic; long term: nocturia; headache on

awakening in back of head or neck

3. risk factors -

a. family history and or race (higher incidence and more severe with

African-Americans)

b. incidence increases with age in US & Europe

c. environmental factors - obesity, poor stress management, excessive

alcohol consumption, high salt intake oral contraceptives, tobacco use

(cigarette smoking reduces MAO levels in lung tissue, and subsequent vasoconstriction)

4. High Blood pressure in children

a. children 3 years through adolescence should have blood pressure

taken annually for basic assessment

b. B.P. influenced by growth and maturation

5. Patho from long-term exposure: loss of elastic (muscle) fibers in medial layer (middle layer), with increased collagen & calcium deposits in the media -- arteriosclerosis (arteriosclerosis = hardening...