Class 10 Flashcards
What are some Hypertension Risk Factors (often interrelated)?
• Lifestyle factors: stress, lack of life balance, inactive lifestyle, social isolation, poor diet, etc.
• Lack of cardiovascular fitness/exercise level
• Smoking
• Aging changes: reduced cardiac resilience, decreased blood vessel elasticity, etc.
• Race: African Americans 1/3 more likely to develop hypertension, especially at younger ages (24-44)
• Family tendency
• Chronic alcohol consumption
• Salt intake? (some people more sensitive than others; may not always cause hypertension but increases water retention)
• Hormonal factors: long-term use of oral contraception, hormone replacement therapy increase risk
• Type 2 diabetes, other health conditions (kidney or lung disease, etc.)
• Cholesterol levels
• Elevated low-density lipoproteins (LDLs) aka “bad cholesterol” LDLs transport cholesterol particles throughout body; LDL cholesterol builds up in walls of arteries, contributing to atherosclerosis development & making them less elastic
• Reduced high-density lipoproteins (HDL), or “good” cholesterol HDLs pick up excess cholesterol & take it back to liver for processing
What are some Signs and Symptoms of Hypertension?
Almost always asymptomatic - “Silent Killer”
When symptoms are present, they are most likely to be so at higher BP levels:
• Headaches
• Nose bleeds - spontaneous
• Dizziness/vertigo
• Fatigue/lethargy
• Mild edema
• Nocturnal urinary frequency
• Blurred vision
What are more severe Signs and Symptoms of Hypertension?
• More intense variations of signs/symptoms
• Vision changes such as diplopia (double vision)
• Nausea/vomiting
• Altered central nervous system functions, eg. irritability & personality changes, confusion/disorientation, altered consciousness
• Fainting
• Evidence of cardiovascular & kidney distress
• Convulsions
What are Long Term Adaptations/Complications/Risks of Systemic Hypertension?
• In milder cases, chronic ongoing damage to organs, potentially leading to heart, kidney, liver, lung damage/failure
• Increased risk of aneurysm, arterial rupture in brain (hemorrhagic stroke) & other types of cerebral bleeds
• Chronic elevated BP correlates highly with atherosclerosis
• Damage to blood vessels, which exacerbates TPR issues & increases ischemic damage throughout body tissues:
What is Onion Skinning (macroangiopathy)?
Change impacts arteries. Tunica intima/interna) becomes damaged due to force of BP – it repairs with scar tissue (more epithelial layers); with continued pressure damage, layers of scar tissue are developed. Scar tissue reduces vessel’s lumen size & makes artery less elastic/flexible, so pressure inside it increases & damage/scarring occurs in negative cycle. Also increases TPR & stress on heart.
What is Hyalinization (microangiopathy)?
Most significant in arterioles, poorly understood thick, goopy, inflexible material, looks like hyaline (“heavy marshmallow”) accumulates in wall, reducing lumen.
Smaller lumen size has two negative effects:
1. increased TPR (adding to the BP problem),
2. reduced blood flow affects diffusion/transfer in capillaries (compromising tissue health).
Resulting tissue Ischemia creates increased calls on heart to work harder to re- establish healthy perfusion.
What are Medical Treatments for Hypertension
• Treatment decisions depend on various case factors, especially BP level at diagnosis.
• Normal progression is to try health behaviour management: lifestyle modifications such as weight loss, increased physical activity, restricting sodium & alcohol intake, stopping smoking, stress management, improving work-life balance, etc.
If these steps are not effective, or if BP is too high at diagnosis, lifestyle modifications are still incorporated, & medications are added.
• Diuretic is usually first drug of choice. Diuretics lower blood volume by increasing urination. If not effective, other drugs are added. Multiple drugs may be required to reach target levels, especially in patients who are also diabetic.
• Low doses of multiple drugs may be more effective & better tolerated than higher doses of fewer drugs. This means while number of hypertensive medications being used in a case could be seen as considered an indicator of hypertension severity, this is no longer the case.
What are Medications used in Managing Hypertension? (> Reduce Total Blood Volume)
˃ Reduce Total Blood Volume
Diuretics
Diuretics act on nephrons in kidney. Goal is to decrease TPR by decreasing total blood volume (via ↑ urine production). Typically first choice of drug for hypertension & often paired with other hypertension medications.
Thiazide diuretics
MOA: ↓ Na+/Cl- resorption @ nephron (water remains in tubules)
S/E: Fluid/electrolyte imbalance (leads to cardiac dysrhythmia, m. weakness/spasm), headaches (HAs), nausea, disorientation
Eg: Microzide
Aldosterone Antagonist/Receptor Blocker
MOA: Inhibits aldosterone’s ability to signal kidneys to retain Na+ & water
S/E: See above
Eg: Aldactone
What are Medications used in Managing Hypertension? (˃ Improve Heart Function)
Attempts to improve heart conditions (lower HR, more efficient contractions, etc.) by acting on either heart itself or CNS.
Beta Blockers
MOA: Competes w/ SyNS NTs (eg. adrenalin) @ beta receptor sites in heart to ↓ HR, better rhythm May also act as peripheral vasodilator
S/E: Breathing difficulties, paresthesia, dysrhythmia, depression, fatigue
Eg: Atenolol
Notes: When used for hypertension, often needs to be combined w/ other meds.
Glycosides
MOA: Modifies NA+/K- dynamics in myocardium to ↓ HR
S/E: Toxicity (can lead to visual disturbances, confusion, GI irritation, dysrhythmia)
Eg: Digitalis
Central-acting Agents
MOA: Inhibits SyNS signals in brain that ↑ HR & vasoconstrict
S/E: N/A
Eg: Catapres
Kidneys release ____________ into circulation when BP is low.
renin
Renin acts on angiotensinogen (circulating in blood, made in liver) to create ___________________.
angiotensin I
Angiotensin I circulates and converts into angiotensin II in ___________ via ___________
lungs via ACE
Angiotensin II is a strong systemic vasoconstrictor which __________ BP
which ↑ BP
