CARDIOVASCULAR MODULE: HYPERTENSION

Adult Medical-Surgical Nursing

Hypertension: Description

Blood pressure elevated above recognised normal value for age on several separate occasions

Hypertension: Classification

Primary hypertension (90 – 95% of cases)

Secondary hypertension (5 -10%)

Primary Hypertension: Aetiology

Unknown cause but may relate to:Stress AtherosclerosisHyperlipidaemiaFamily historySmokingObesity Diabetes Mellitus (macrovascular)

Secondary Hypertension: Aetiology

Chronic renal disease

Primary Hypertension: Pathophysiology

Interaction of hyperlipidaemia and atherosclerosis

Hypertension contributes to rate at which plaque develops, therefore:

Prolonged hypertension damages blood vessels supplying target organs: heart, kidneys (renal arteries), brain, eyes, peripheral vessels

Secondary Hypertension: Pathophysiology

Chronic renal disease →Increased fluid volumeSodium retentionImbalance of renin - angiotensin system:→Increased vasoconstriction and blood volume

Hypertension: Clinical

Manifestations

May be asymptomaticHeadache often frontalSymptoms related to associated medical

conditions:Cardiac diseaseRenal diseaseStrokeImpaired vision

Hypertension: Diagnosis

BP: serial measurementECGKidney function testsLiver function testsLipid profileBlood glucoseSerum electrolytes

Hypertension: Management

Calcium channel blockersβ blockersAlpha blockersCentral action anti-hypertensivesACE inhibitorsDiuretics

Hypertension: Management

Calcium channel blockers:

Vasodilation (oppose vasospasm) Reduce peripheral constriction, opening up

peripheral circulation to allow redistribution of blood

↓ afterload

Hypertension: Management

β blockers: Slow heart rate (↓ sympathetic action) Vasodilation

Alpha blockers: Peripheral vasodilation (↓ sympathetic action)

Hypertension: Management

Central acting hypotensives:

Reduce sympathetic activity from the level of the medulla (cardiac centre) in the brain

Hypertension: Management

ACE inhibitors:

Block the conversion of Angiotensin I → II

Vasodilation

↓ Na - retaining effect of Aldosterone

Hypertension: Management

Diuretics:

Diuresis relieves pressure of fluid overload

Frusemide also acts as a vasodilator

Aldactone: inhibits Na re-absorption (competes with Aldosterone)

Hypertension: Nursing

Considerations

Health education related to a healthy lifestyle:

Diet (low salt, low fat, high fruit and fibre)Anti-stress relaxation therapyExerciseAvoid smokingRegular BP check/ adherence to medication