Hypertension: Pathophysiology, Physical Assessment, Pharmacology
Study Notes
A. Definition
● Hypertension, or high blood pressure, is a condition where the force of the blood against
the artery walls is too high, often defined as blood pressure above 140/90 mmHg, and
considered severe if the pressure is above 180/120 mmHg.
B. Classification
● Normal: Systolic <120 mm Hg and Diastolic <80 mm Hg
○ Reassess in 1 year.
● Elevated: Systolic 120-129 mm Hg and Diastolic <80 mm Hg
○ Reassess in 3–6 months.
○ Nonpharmacological management.
● Hypertension Stage 1: Systolic 130-139 mm Hg or Diastolic 80-89 mm Hg
○ Nonpharmacological management and reassess in 3–6 months.
○ If the patient has heart disease or risk factors, start antihypertensive medication.
Reassess in 1 month
● Hypertension Stage 2: Systolic ≥140 mm Hg or Diastolic ≥90 mm Hg
○ Start antihypertensive medication along with nonpharmacological management.
Reassess in 1 month.
● Hypertensive Crisis: Systolic >180 mm Hg and/or Diastolic >120 mm Hg
○ Requires emergent intervention.
C. Risk Factors
● Nonmodifiable: Age, family history, race (higher in African Americans), gender (more
common in men until age 64, then more common in women).
● Modifiable: Obesity, sedentary lifestyle, smoking, high salt intake, excessive alcohol
consumption, stress, chronic conditions (e.g., kidney disease, diabetes).
D. Pathophysiology
Involves several key mechanisms:
1. Genetic Factors: Genetic predisposition plays a significant role, with specific genes
influencing blood pressure regulation through pathways such as the
renin-angiotensin-aldosterone system (RAAS), sympathetic nervous system (SNS), and
renal function.
, 2. Renin-Angiotensin-Aldosterone System (RAAS): This hormonal system regulates
blood pressure and fluid balance. Overactivity of RAAS can lead to increased blood
volume and vasoconstriction, raising blood pressure. Angiotensin II, a potent
vasoconstrictor, and aldosterone, which promotes sodium and water retention, are key
components.
3. Sympathetic Nervous System (SNS) Overactivity: Increased SNS activity can lead to
vasoconstriction, increased heart rate, and higher cardiac output, all of which elevate
blood pressure. Chronic stress and certain lifestyle factors can enhance SNS activity.
4. Endothelial Dysfunction: The endothelium (inner lining of blood vessels) plays a crucial
role in vascular tone regulation by releasing vasodilators like nitric oxide.
Dysfunction of the endothelium can lead to reduced production of vasodilators and
increased production of vasoconstrictors, contributing to hypertension.
5. Kidney Function: The kidneys regulate blood pressure by controlling fluid and
electrolyte balance. Impaired kidney function can lead to sodium and water retention,
increasing blood volume and pressure.
6. Vascular Remodeling: Chronic hypertension can cause structural changes in blood
vessels, such as thickening of the arterial walls (arteriosclerosis) and reduced elasticity,
which increase peripheral resistance and further elevate blood pressure.
7. Lifestyle Factors: Diet high in sodium, obesity, physical inactivity, excessive alcohol
consumption, and smoking are significant contributors to hypertension. These factors
can influence the aforementioned mechanisms, exacerbating the condition.
8. Hormonal Factors: Hormones like aldosterone, cortisol, insulin, and thyroid hormones
can affect blood pressure regulation by influencing sodium retention, vascular tone, and
SNS activity.
E. Symptoms
● Often asymptomatic.
● Severe hypertension may cause headaches, shortness of breath, nosebleeds, or other
symptoms.
F. Complications
● Heart attack or stroke.
● Aneurysm.
● Heart failure.
● Weakened and narrowed blood vessels in the kidneys.
● Thickened, narrowed, or torn blood vessels in the eyes.
● Metabolic syndrome.
, ● Trouble with memory or understanding.
G. Diagnosis
● Blood pressure measurement using a sphygmomanometer.
● Ambulatory blood pressure monitoring.
● Home blood pressure monitoring.
● Laboratory tests: Urinalysis, blood tests (cholesterol, blood sugar), ECG,
echocardiogram.
H. Physical Assessment
Involves a comprehensive evaluation to confirm the diagnosis, identify potential causes, and
assess for any complications. The key components include:
1. Patient History:
○ Medical History: Inquire about any history of hypertension, cardiovascular
disease, diabetes, kidney disease, and other relevant conditions.
○ Family History: Ask about a family history of hypertension, heart disease, stroke,
or other related conditions.
○ Lifestyle Factors: Assess diet, physical activity, smoking, alcohol consumption,
and stress levels.
○ Medication Use: Review current and past medications, including over-the-counter
drugs and supplements.
2. Blood Pressure Measurement:
○ Preparation: Ensure the patient is seated comfortably with their back supported,
legs uncrossed, and arm supported at heart level. The patient should rest for at
least 5 minutes before the measurement.
○ Cuff Size: Use an appropriately sized blood pressure cuff.
○ Technique: Measure blood pressure in both arms using a validated
sphygmomanometer or automated device. Take multiple readings at different
times to confirm the diagnosis. Consider measuring blood pressure in different
positions (sitting, standing, lying down) to assess for orthostatic hypotension.
3. General Physical Examination:
○ General Appearance: Observe for signs of obesity, stress, or other physical
conditions.
○ Vital Signs: Measure heart rate, respiratory rate, and temperature.
4. Cardiovascular Examination:
○ Heart: Auscultate for heart sounds, murmurs, or abnormal rhythms. Palpate for
any abnormal pulsations or thrills.
○ Peripheral Pulses: Check peripheral pulses (radial, femoral, dorsalis pedis,
posterior tibial) for strength and symmetry.
Study Notes
A. Definition
● Hypertension, or high blood pressure, is a condition where the force of the blood against
the artery walls is too high, often defined as blood pressure above 140/90 mmHg, and
considered severe if the pressure is above 180/120 mmHg.
B. Classification
● Normal: Systolic <120 mm Hg and Diastolic <80 mm Hg
○ Reassess in 1 year.
● Elevated: Systolic 120-129 mm Hg and Diastolic <80 mm Hg
○ Reassess in 3–6 months.
○ Nonpharmacological management.
● Hypertension Stage 1: Systolic 130-139 mm Hg or Diastolic 80-89 mm Hg
○ Nonpharmacological management and reassess in 3–6 months.
○ If the patient has heart disease or risk factors, start antihypertensive medication.
Reassess in 1 month
● Hypertension Stage 2: Systolic ≥140 mm Hg or Diastolic ≥90 mm Hg
○ Start antihypertensive medication along with nonpharmacological management.
Reassess in 1 month.
● Hypertensive Crisis: Systolic >180 mm Hg and/or Diastolic >120 mm Hg
○ Requires emergent intervention.
C. Risk Factors
● Nonmodifiable: Age, family history, race (higher in African Americans), gender (more
common in men until age 64, then more common in women).
● Modifiable: Obesity, sedentary lifestyle, smoking, high salt intake, excessive alcohol
consumption, stress, chronic conditions (e.g., kidney disease, diabetes).
D. Pathophysiology
Involves several key mechanisms:
1. Genetic Factors: Genetic predisposition plays a significant role, with specific genes
influencing blood pressure regulation through pathways such as the
renin-angiotensin-aldosterone system (RAAS), sympathetic nervous system (SNS), and
renal function.
, 2. Renin-Angiotensin-Aldosterone System (RAAS): This hormonal system regulates
blood pressure and fluid balance. Overactivity of RAAS can lead to increased blood
volume and vasoconstriction, raising blood pressure. Angiotensin II, a potent
vasoconstrictor, and aldosterone, which promotes sodium and water retention, are key
components.
3. Sympathetic Nervous System (SNS) Overactivity: Increased SNS activity can lead to
vasoconstriction, increased heart rate, and higher cardiac output, all of which elevate
blood pressure. Chronic stress and certain lifestyle factors can enhance SNS activity.
4. Endothelial Dysfunction: The endothelium (inner lining of blood vessels) plays a crucial
role in vascular tone regulation by releasing vasodilators like nitric oxide.
Dysfunction of the endothelium can lead to reduced production of vasodilators and
increased production of vasoconstrictors, contributing to hypertension.
5. Kidney Function: The kidneys regulate blood pressure by controlling fluid and
electrolyte balance. Impaired kidney function can lead to sodium and water retention,
increasing blood volume and pressure.
6. Vascular Remodeling: Chronic hypertension can cause structural changes in blood
vessels, such as thickening of the arterial walls (arteriosclerosis) and reduced elasticity,
which increase peripheral resistance and further elevate blood pressure.
7. Lifestyle Factors: Diet high in sodium, obesity, physical inactivity, excessive alcohol
consumption, and smoking are significant contributors to hypertension. These factors
can influence the aforementioned mechanisms, exacerbating the condition.
8. Hormonal Factors: Hormones like aldosterone, cortisol, insulin, and thyroid hormones
can affect blood pressure regulation by influencing sodium retention, vascular tone, and
SNS activity.
E. Symptoms
● Often asymptomatic.
● Severe hypertension may cause headaches, shortness of breath, nosebleeds, or other
symptoms.
F. Complications
● Heart attack or stroke.
● Aneurysm.
● Heart failure.
● Weakened and narrowed blood vessels in the kidneys.
● Thickened, narrowed, or torn blood vessels in the eyes.
● Metabolic syndrome.
, ● Trouble with memory or understanding.
G. Diagnosis
● Blood pressure measurement using a sphygmomanometer.
● Ambulatory blood pressure monitoring.
● Home blood pressure monitoring.
● Laboratory tests: Urinalysis, blood tests (cholesterol, blood sugar), ECG,
echocardiogram.
H. Physical Assessment
Involves a comprehensive evaluation to confirm the diagnosis, identify potential causes, and
assess for any complications. The key components include:
1. Patient History:
○ Medical History: Inquire about any history of hypertension, cardiovascular
disease, diabetes, kidney disease, and other relevant conditions.
○ Family History: Ask about a family history of hypertension, heart disease, stroke,
or other related conditions.
○ Lifestyle Factors: Assess diet, physical activity, smoking, alcohol consumption,
and stress levels.
○ Medication Use: Review current and past medications, including over-the-counter
drugs and supplements.
2. Blood Pressure Measurement:
○ Preparation: Ensure the patient is seated comfortably with their back supported,
legs uncrossed, and arm supported at heart level. The patient should rest for at
least 5 minutes before the measurement.
○ Cuff Size: Use an appropriately sized blood pressure cuff.
○ Technique: Measure blood pressure in both arms using a validated
sphygmomanometer or automated device. Take multiple readings at different
times to confirm the diagnosis. Consider measuring blood pressure in different
positions (sitting, standing, lying down) to assess for orthostatic hypotension.
3. General Physical Examination:
○ General Appearance: Observe for signs of obesity, stress, or other physical
conditions.
○ Vital Signs: Measure heart rate, respiratory rate, and temperature.
4. Cardiovascular Examination:
○ Heart: Auscultate for heart sounds, murmurs, or abnormal rhythms. Palpate for
any abnormal pulsations or thrills.
○ Peripheral Pulses: Check peripheral pulses (radial, femoral, dorsalis pedis,
posterior tibial) for strength and symmetry.
