HYPERTENSION

WHAT IS BLOOD PRESSURE

Blood pressure is the force with which blood pushes against the artery walls as it travels through the body. Systolic pressure measures cardiac output and refers to the pressure in the arterial system at its highest. Diastolic pressure measures peripheral resistance and refers to arterial pressure at its lowest .Normal blood pressure for an adult is 120/80 (on average).

DEFINITION

Defined as a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140 with a diastolic pressure above 90.

INCIDENCE

It is world wide epidemic with an estimated 690 million people

Increases with age More prevalent in male. Higher in African Whites than in whites

Primary Hypertension: A condition which is characterized by high blood pressure not associated with any identifiable pathological cause Secondary Hypertension: Secondary hypertension is high blood pressure resulting from an underlying cause such as kidney disease

TYPES

CLASSIFICATION

Classification of blood pressure for adults

Categorysystolic, mmHg

diastolic, mmHg

Hypotension < 90 < 60   

Normal  90 – 119 60 – 79   

Prehypertension 120 – 139 80 – 89  

Stage 1 Hypertension

140 – 159 90 – 99  

Stage 2 Hypertension

≥ 160 ≥ 100  

The following classification of blood pressure applies to adults aged 18 and older. It is based on the average of seated blood pressure readings that were properly measured during 2 or more office visits.

White coat hypertension: White coat hypertension is a term used to describe a condition where patients have increased blood pressure readings when measured in a clinical setting such as a doctor's office. Blood pressure readings taken in the home environment while the patient is relaxed are normal. The underlying cause is believed to be tension and anxiety associated with visiting health professionals such as general practitioners. Isolated systolic hypertension: Often in older adults the first number (the upper or systolic number) is high while the second (the lower or diastolic) number is normal.

Malignant hypertension: Malignant hypertension is a condition characterized by very high blood pressure and swelling of the optic nerve. This type of hypertension is more common in people with kidney problems such as narrowed kidney blood vessels. The condition is a medical emergency which can cause organ damage if not treated promptly

ETIOLOGY

RISK FACTORS

o Stress.o Obesity. o Lack of vitaminDo Excess intake of salto Alcoholism o Cigarettesmokingo Diabetes mellitus o Elevated serum

lipids

o Age.o Gender.o Family historyo Ethnicity.

MODIFIABLE FACTORS NONMODIFIABLE

FACTORS

CLINICAL MANIFESTATIONS

Severe head acheFatigue or confusion Dizziness Nausea Problems with vision Chest pains Breathing problems Irregular heartbeat Blood in the urine

COMPLICATIONS

DIAGNOSTIC EVALUATION

The medical and family history help the physician determine if the patient has any conditions or disorders that might contribute to or cause the hypertension. A family history of hypertension might suggest a genetic predisposition for hypertension. The physical exam may include several blood pressure readings at different times and in different positions. The physician uses a stethoscope to listen to sounds made by the heart and blood flowing through the arteries. The pulse, reflexes, and height and weight are checked and recorded. Internal organs are palpated, or felt, to determine if they are enlarged.Because hypertension can cause damage to the blood vessels in the eyes, the eyes may be checked with a instrument called an ophthalmoscope. The physician will look for thickening, narrowing, or hemorrhages in the blood vessels.A chest x ray can detect an enlarged heart, other vascular (heart) abnormalities, or lung disease.An electrocardiogram (ECG) measures the electrical activity of the heart. It can detect if the heart muscle is enlarged and if there is damage to the heart muscle from blocked arteries.Urine and blood tests may be done to evaluate health and to detect the presence of disorders that might cause hypertension.

BLOOD PRESSURE MONITORING OPTHALMOSCOPE

NON PHARMACHOLOGICAL MANAGEMENT Weight reduction . Increased physical activity Limited alcohol consumption Reduced salt (sodium

chloride) intake Increased potassium intake Stress reduction technique

PHARMACHOLOGICAL MANAGEMENT Drug classes Commonly used classes of

antihypertensive drugs are the Thiazide diuretics (e.g.,

bendroflumethiazide) Beta-blockers (e.g., propranolol, atenolol) Angiotensin-converting enzyme inhibitors

(e.g., captopril, enalapril), Angiotensin II antagonists (e.g.,

candesartan, losartan), Calcium channel blockers (e.g.,

amlodipine, nifedipine) and alpha-blockers (e.g., doxazosin

HYPERTENSIVE CRISIS

DEFINITION

Hypertensive crises encompass a spectrum of clinical situations that have in common severely elevated blood pressure (BP), usually higher than 180/110 mm Hg, together with progressive or impending target organ damage.

Hypertensive crises affect upward of 500,000 Americans each year.

CAUSESoChronic hypertension with acute exacerbation (most common) oReno vascular hypertension oParenchymal Renal Disease

Acute glomerulonephritis Renal Infarction Vasculitis

oScleroderma Renal Crisis oDrug Ingestion

Tricyclic anti-depressants Monoamine Oxidase (MAO) Inhibitors Cocaine Amphetamines

oAnti-hypertensive drug withdrawal or failed compliance

Centrally acting anti-hypertensives (eg. clonidine) Peripheral alpha blockers (eg. prazosin) Beta-Blocker acute withdrawal

oPre-eclampsia and Eclampsia oAutonomic hyperactivity

Guillain-Barre Syndrome Spinal Cord Injury

oPheochromocytoma

HYPERTENSIVE URGENCY

Hypertensive Urgency is defined as a clinical setting of severe hypertension  with minimal or no symptoms, where severe elevation of BP are not causing immediate end-organ damage but should be effectively lowered within 24 hours to reduce potential risk to the patient.

HYPERTENSIVE EMERGENCY

Hypertensive emergencies are severe elevations in BP, often higher than 220/140 mm Hg, complicated by clinical evidence of progressive target organ dysfunction. These patients require immediate admission and BP reduction (not necessarily to normal ranges) to prevent or limit further target organ damage. Examples include hypertensive encephalopathy, intracranial hemorrhage, acute myocardial infarction, acute left ventricular failure with pulmonary edema, dissecting aneurysm, acute renal failure, and eclampsia of pregnancy

CLINICAL MANIFESTATIONS

Blood Pressure (mm Hg)

Funduscopic Findings

Neurologic Status

Cardiac Findings

Renal Symptoms

Gastrointestinal

Symptoms

Usually >220/140

Hemorrhages, exudates, papilledema

Headache, confusion, somnolence, stupor, visual loss, seizures, focal neurologic deficits, coma

Prominent apical pulsation, cardiac enlargement, congestive heart failure

Azotemia, proteinuria, oliguria

Nausea, vomiting

Table 1: Clinical Characteristics othe Hypertensive Emergency

Severe Hypertension (Urgency)

Parameter Asymptomatic SymptomaticHypertensive Emergency

Blood pressure (mm Hg)

>180/110 >180/110 Usually >220/140

SymptomsHeadache, anxiety; often asymptomatic

Severe headache, shortness of breath

Shortness of breath, chest pain, nocturia, dysarthria, weakness, altered consciousness

Examination

No target organ damage, no clinical cardiovascular disease

Target organ damage; clinical cardiovascular disease present, stable

Encephalopathy, pulmonary edema, renal insufficiency, cerebrovascular accident, cardiac ischemia

Therapy

Observe 1-3 hr; initiate, resume medication; increase dosage of inadequate agent

Observe 3-6 hr; lower BP with short-acting oral agent; adjust current therapy

Baseline laboratory tests; intravenous line; monitor BP; may initiate parenteral therapy in emergency room

Plan

Arrange follow-up within 3-7 days; if no prior evaluation, schedule appointment

Arrange follow-up evaluation in less than 72 hr

Immediate admission to ICU; treat to initial goal BP; additional diagnostic studies

Intravenous Drugs:Sodium Nitroprusside •Standard rapidly acting agent effective in many cases •Dose is 0.25-8 µg/kg/minute as IV infusion, start with 0.3- 0.5 ug/kg/min (about 20-50 ug/min), then 1- 3 ug/kg/min IV (max:<10 ug/kg/min) (50 mg in 250 ml D5W) •Onset: 0.5 -1 min ; Duration: 2 - 5 min •Adverse effects: hypotension, N&V, apprehension, cyanide (thiocyanate level>10 mg/dl is toxic; >20 mg/dl may be fatal) toxicity convulsion, twitching, psychosis, dizziness, etc.

•Nitroprusside has decreased efficacy in renal failure Toxic levels of cyanide build

Nitroglycerin Highly effective in setting of coronary ischemia, acute coronary syndromes Dose is 5-100µg/min as IV infusion Nitroglycerin IV infusion start 5- 10 ug/min then may be up to >200 ug/min prn esp. in pts where Na nitroprusside is relatively contraindicated & in pts with ischemic heart disease, impaired renal or hepatic function. Onset: immediate; Duration:1- 5 min May cause headache, tachycardia, vomiting, methemoglobinemia Excellent for titrating blood pressure in setting of coronary ischemia

Labetalol (Trandate) •Mixed alpha/beta blocker, excellent for most hypertensive emergencies •Dose is 20-80mg IV bolus every 10 minutes or 0.5-2mg/min infusion IV .Start 20 mg IV, then 20- 80 mg q10 min prn, or start with 0.5 mg/min infusion, then 1- 2 mg/min (may be up to 4 mg/min) IV infusion up to 300 mg/d max.

Onset: 5 -10 min; Duration: 3- 6 h Adverse effects: hypotension, bradycardia, dizziness, scalp tingling

•Avoid in patients with heart block, bradycardia, CHF, severe asthma or bronchospasm •First or second line for eclampsia; excellent in catecholamine surges

Enalaprilat •Intravenous formulation of enalapril (ACE inhibitor) •Dose is 1.25-5.0mg q6 hour IV (duration of action ~6 hours) •Onset of action in 15-30 minutes; Duration 6 hours or more •Highly variable response; precipitous BP drop in high-renin states, rarely angioedema, hyperkalemia, or acute renal failure. •May be most useful in acute cardiogenic pulmonary edema •Avoid in acute myocardial infarction

Diltiazem (Cardizem) •Initial dose 0.25 mg/kg over 2 min, followed by infusion of 0.35 mg/kg at an initial rate of 10 mg/hour •Onset: 3-30 min •Adverse effects: excessive hypotension, flushing; rarely amblyopia

Treatment of Hypertensive Emergency •Encephalopathy: Nitroprusside, Labetolol, Diazoxide •Cerebral Infarction: no treatment (hemorrhage control), Nitroprusside, Labetolol •Myocardial Ischemia, Infarction: Nitroglycerine, Labetolol, ß-adrenergic blockers •Acute Pulmonary Edema: Nitroprusside (or Nitroglycerin) and Loop Diuretic •Aortic Dissection: Nitroprusside and ß-adrenergic blockers, Labetolol •Eclampsia: Hydralazine, Labetolol, Diazoxide •Acute Renal Insufficiency: Nitroprusside, Labetolol, Ca antagonists •Funduscopic changes: Nitroprusside, Labetolol, Ca antagonists •Hemolytic Anemia, Microangiopathic: Nitroprusside, Labetolol, Ca antagonists .

i. Check the B.P hourlyii. Administer the medicationiii. Provide low sodium and caloric dietiv. Encourage the patient for cessation of

smoking.v. Check the weight of the patient.vi. Teach about the stress reduction

technique.vii. Provide health education.

In effective therapeutic regimen management related to new diagnosis.

Imbalanced nutrition; more than body requirement related to high sodium and caloric intake.

In effective health maintenance related to lack of regular exercise

Know your blood pressure

Cessation of smoking Avoidance of alcoholism

Weight control

REGULAR EXERCISE AVOID STRESS

EAT LOW FAT DIET

Hypertension is a silent killer disorder.Un treated hypertension lead to hypertensive crisis. It is an emergency. It is prevented by adequate life style modification.