Hypertension health assessment

BLOOD PRESSURE & HYPERTENSION

BLOOD PRESSURE

Is an integral part of a clinical practiceThe 4th vital sign (T, P, R)It is obtained at every physical

examination Including outpatient visits Hospitalized patients (at least daily) Before most medical procedures When following a hypertensive patient assist

with tailoring of medications and treatment of HTN.

Integral part in identifying if a patient is in potential or actual clinical deterioriation.

BLOOD PRESSURE- indications

For hypertension screeningAssessing a person’s suitability for a sportIn some certain occupationsEstimating cardiovascular riskDetermining risk for various medical

procedures.

BLOOD PRESSURE-contraindications

Avoid obtaining BP in the same arm with an arteriovenous fistula (such as used in hemodialysis) is present (use the other arm)

Avoid obtaining BP if the patient has lymphadema or at risk for developing lymphadema (such as after lymph node dissection for TX of breast CA) (use the other arm)

If with bilateral AV fistula or lymphadema exists, obtain BP at the lower extremity

BLOOD PRESSURE- delay

Delaying of taking BP if the patient has: Smoked within 30 minutes (increases BP) Exercised (decreases BP) Taking caffeine or other exogenous adrenergic

stimulants (acutely increases BP)

BLOOD PRESSURE- equipment

Manual blood pressure cuff with any standard stethoscope Mercury sphygmomanometer (accurate

but toxic)Aneroid sphygmomanometer (non-toxic

yet needs calibration every 6 months) A difference of 4mmHg between the

mercury and aneroid needs calibration


Any standard stethoscope can be used to auscultate the Korotkoff sounds

Diaphragm is used mostly than the bell (due to ease of use)

No need to use the stethoscope when using the automated oscillometric cuff.


Automated oscillometric devices More common to use due to ease of use and

availability Obtain systolic measurement by detecting

oscillations on the lateral walls of the occluded artery as the cuff is deflated.

Measurements obtained from automated measuring devices are typically lower than those obtained from manual devices.


Cuffs Are available in numerous sizes Essential to find a proper-sized cuff Measurements with an inappropriately small cuff may

result in an overestimation of the true systolic pressure

BLOOD PRESSURE- equipmentcuff sizes according to Pickering

et al.Arm Circumference

22-26 cm 27-34 cm 35-44 cm 45-52 cm

Cuff Measurement/Size

12x22cm 16x30 cm 16x36 cm 16x42 cm

Small adult cuff Adult cuff Large

adult cuffAdult thigh

cuff

BLOOD PRESSURE-positioning

Vital in obtaining a blood pressure measurement

Patient should be in a seated position at least 5 minutes, comfortable and relaxed in a chair with back support, uncrossed legs and feet should rest comfortably on the floor

BLOOD PRESSURE-positioning

Once examiner is ready, the arm should be supported comfortably at the level of the heart

False reading may be measured if arm is above or below the heart.

Sphygmomanometer should be visible to the examiner and is comfortably positioned

No restrictive clothing should be on the patient’s arm

BLOOD PRESSURE-technique

Stethoscope should be placed lightly over the brachial artery.

Inflate the cuff to a pressure of 30mmHg above the level at which the radial pulse is no longer palpable

While deflating the cuff, listen for Korotkoff phase I(first pulse is auscultated), also known as the systolic blood pressure


While watching the sphygmomanometer, continue to slowly deflate the cuff.

A abrupt soft, indistinct, muffling sound may be heard (Korotkoff IV)

Then continue listening until the sounds disappear completely (Korotkoff V)


If there is a 10mmHg or greater difference between phase IV and phase V, then the pressure reading in phase IV is recorded as the diastolic pressure. This occur in: High cardiac output Peripheral vasodilation Children < 13 yrs old Pregnant women


After the last sound is heard, continue to deflate the cuff for another 10mmHg and then completely.

Allow the patient to restWait at least 30 seconds and repeat previous

3 steps until 2 consecutive readings are obtained


Wait another 1-2 minutes and repeat steps 4-10

The arm with the highest measurement is to be used

When recording, note the BP, arm used, arm position and cuff size used.


Thigh must be used there are contraindications to upper extremity measurements

Wrist must be used for obese patientsMeasurements recorded using these

alternatives may be higher due to increased hydrostatic pressure related to the lower position of the thigh and wrist to the heart


When using the automated oscillometric device, same steps are applied when using the wrist.

BLOOD PRESSURE-complications

Are minimal that only includes discomfort of the arm.

BLOOD PRESSURE-patient education

Patient should be given the resultsIf pressure is above normal (above 120/80),

patient is advised to follow up with their health care provider

If patient is demonstrating any signs of hypertensive emergencies they should referred immediately to a physician or emergency room.

Hypertension

Is sustained elevation of BPsystolic blood pressure (SBP) of >140mmHg

diastolic blood pressure of >90mmHg

Classification of BP aged 18 years old and above based on the

recommendations of the 7th report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of

High Blood Pressure (JNC 7)classification SBP DBP

Normal <120 <80Pre-

hypertension 120-139 80-89

Stage I 140-159 90-99Stage 2 >160 >100

Hypertensive Crisis >180 >110

Cause/Etiology

Primary or Essential Hypertension (85-95% of cases) Plasma Volume Renin-Angiotensin System Heredity Dietary Sodium Obesity Stress Age >65

Cause/EtiologySecondary Hypertension

Primary Aldosteronism Renal Parenchymal Disease (Chronic

glumerulonephritis, Pyelonephritis, Polycystic renal disease, connective tissue disorders, obstructive uropathy)

Renovascular disease Pheochromocytoma Cushing Syndrome Congenital adrenal hyperplasia

Cause/EtiologySecondary Hypertension

Hyperthyroidism Myxedema Coarctation of the aorta Excessive alcohol intake Oral contraceptives Sympathomimetics NSAIDs Corticosteroids Coccaine Licorice

Pathophysiology

Blood pressure = cardiac output x total peripheral vascular resistance Pathogenic mechanisms must involve:

Increased C.O. Increased T.P.R. Both

CO is normal but TPR is increased in most patients ( primary HTN, HTN due to primary aldosteronism, pheochromocytoma, renovascular disease and renal parenchyma disease.

Pathophysiology

In other patients, CO is increased (venoconstriction in large veins) and TPR is inappropriately normal for the level of CO. Later, TPR increases and CO returns to normal probably due to autoregulation

Plasma volume tends to decrease as BP increase Plasma volume tends to be high in primary aldosteronism or

renal parenchyma and quite low in hypertension with pheochromocytoma

Renal blood flow decreases as diastolic BP increases and arteriolar sclerosis begins

GFR remains normal until late in the disorder and as a result, filtration factor is increased

Coronary, cerebral and muscle blood flow is maintained unless severe atherosclerosis coexists in these vascular beds.

Pathophysiology

Abnormal Sodium Transport

abnormal sodium

transport

• defective Na-K pump (may occur in normal BP children of HTN parents)

• inhibitive Na-K pump• increased permeability to sodium ions

increased intracellular

sodium

• sensitive to sympathetic stimulation• calcium follows sodium so accumulation of intra-Ca may be

responsible to increased sensitivity

Norepinephrine

• Inhibition of this Na-K pump enhance effects of norepinephrine• Thus increasing BP

Pathophysiology

Sympathetic stimulation increases BP usually more in pre-hypertensive

patients, hypertensive patients than in normotensive patients

Unknown cause High resting pulse rate is an predictor of hypertension Plasma catecholamine levels at rest are higher than

normal in HTN patientsRenin-Angiotensin-Aldosterone System

Pathophysiology

Vasodilator deficiency If not produced by the kidneys, they can cause

hypertension, rather than excess of a vasoconstrictor (angiotensin and norepinephrine)

Bradykinin and nitric oxide are examples of vasodilators Endothelial dysfunction greatly affectly BP since

vasodilators and vasoconstrictors are produced in endothelial cells

Complications

No pathologic changes occur during early stages Severe or prolonged HTN damages target

organs (CV system, brain and kidneys) and can cause CAD and MI CHF Stroke (Hemorrhagic) Renal Failure Blindness Sexual Dysfunction Death

Complications

Signs and Symptoms

Asymptomatic until complications develop in target organs Uncomplicated hypertension causes:

Dizziness Flushed facies Headache Fatigue Epistaxis Nervousness

Diagnosis

Multiple BP measurements to confirmU/A, urinary albumin, creatinine ratio; if ABN

consider renal ultrasonographyFasting lipids, creatinine, potassiumECG: if with LVH consider echocardiographyThyroid-stimulating hormone measurementHistory and physical examination to

determine etiology

Treatment

Nursing Interventions/Lifestyle Modifications Weight loss and exercise Smoking cessation Diet: increased F/V and decrease salt, limit alcohol Drugs if unrespomsive to lifestyle modifications

Medications Diuretics – reduce plasma volume and reduce vascular

resistance, shift of Na from intra-Cell to extra-Cell Thiazide-type diuretics (hydrochlorothiazide,

indapamide) Loop diuretics (furosemide) Potassium-sparing diuretics (spironolactone)

Treatment

Beta-blockers – slow HR and reduce myocardial contractability Carvedilol Metropolol

Calcium Channel blockers – potent peripheral vasodilators and reduce blood pressure by decreasing TPR, sometimes cause reflexive tachycardia Amlodipine Nifedipine Nicardipine

ACE inhibitors – interfering the conversion of angiotensin I to angiotensin II and by inhibiting the degradation of bradykinin, decreasing peripheral vascular resistance without reflex tachycardia. Most common side effect is a dry cough

Treatment

Captopril Enalapril

Angiotensin II receptor blockers – block Angio II receptors and interfering with the renin-angiotensin system Losartan Telmisartan

Direct renin inhibitor Aliskiren

Adrenergic Modifiers – reduce sympathetic nervous activity Methyldopa

Direct Vasodilator – work directly on the blood vessels, independent of the ANS Hydralazine

Health & Medicine

Hypertension health assessment