Hypertension Flashcards
(26 cards)
Systolic bp ranges
Normal: 120 or less
Pre-high: 121 - 139
High: 140 or above
Systolic Bp (the higher number)
the pressure of the blood again the artery walls when heart CONTRACTS
Diastolic Bp ranges
Normal: 80 or less
Pre-high: 81-89
High: 90 or above
Diastolic Bp (the lower number)
the pressure against the artery walls when the heart RELAXES between beats.
Pressure direction in Arteries and Veins
Arteries (higher p): Net p out
Veins (lower p): Net p in
Pressure and fluid movement in Art and Vein
Arterial end: +10mmHg, fluid exits capillary as the hydrostatic pressure is greater than blood osmotic pressure
Venous end: -7mmHg, fluid re-enters capillary as hydrostatic pressure is less than blood osmotic pressure.
Regulation of Bp (short term) (receptors)
Baroreceptors
- Internal Carotids, Aortic Arches
Chemoreceptors
- Changes in pH (hydrogen ion, O2, CO2)
- Internal Carotids, Aortic Arches
Regulation of BP (blood related)
FORCE by which blood is pushed through the sys
VOLUME of blood in the sys
DIAMETER of conducting vessels.
Amount pumped depends on
❤️ rate, contractibility, muscle health
Factors affecting arterial blood pressure
Blood Pressure= Peripheral resistance x Cardiac output
BP = PR x CO
Peripheral Resistance (PR)
‘back pressure’ against heart attempt to pump the blood into the cardiac sys => ⬆️ BP
in essence: PR is the blood pressure
CAriac Output (CO) (effectiveness of ❤️
Its the vol of blood pumped out per min (ml/min). The more is pumped out = higher BP
CO = HR x Stroke vol
4 main hydrostatic parameters factors that determine BP (Anti-hypertension drugs affect all of these process)
- Blood Volume
- Effectiveness of heart
- Resistance of the blood flow
- Relative distribution of blood between arterial and venous vessels
Blood volume determined by
fluid intake
fluid loss (eg diuretics) may be passive, regulated at kidney
Effectiveness of heart determined by
Aka cardiac output
heart rate
stroke volume
Resistance of blood flow determined by
Diameter of ARTERIOLES
Distribution of blood between A and V vessels determined by
Diameters of VEINS
Hypertension Treatment aims to ⬇️ BP By
⬇️ Cardiac function-related (CO)
⬇️ Blood volume (peripheral resistance)
Indications that could be more prevalent (since high BP is usually asymptomatic)
Sleep disturbance 😴
Emotional upset 😖
Dry mouth 👅🚫💦
Primary Hypertension (92%)
no clear single identifiable cause, but if any of the following factors get disturbed then lead to primary hypertension.
- Adrenergic nervous sys
- RAAS
- Renal function changes
- Hormonal factor
- Vascular endothelium
- Hemodynamic changes (changes in CO and PR)
Secondary Hypertension (8%)
can be attributed(归因于) to a specific cause. Medical conditions such as
- Pregnancy
- Cushing’s Syndrome
- Pheochromocytoma ( a tumor that secretes catecholamines)
- Constriction of Aorta
Risk factors (none / modifiable)
Non-modifiable: age, male, family history of premature cardiac disease
Modifiable: Lifestyle
Treatment goals and how
⬇️ risk of cardiac disease, target organ damage, mortality
Reduce SBP <140mmHg, or by at lease 20
Reduce DBP <90mHg
A combo of meds and lifestyle mod are needed.
Long term BP relugation (RASS)
Renin-Angiotensin-Aldosterone System
⬇️ BP -> release renin in kidney -> convert Angiotensinogen to AT1 -> AT2
AT2 DIRECTLY -> vasoconstriction (BP⬆️)
AT2 INDIRECTLY -> Aldosteron release @ Adrenal gland-> Na + H2O retention (BP⬆️)
