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General Medical Officer (GMO) Manual: Clinical Section
Hypertension (HTN)
Department of the Navy
Bureau of Medicine and Surgery
Peer Review Status: Internally Peer Reviewed
(1) Introduction
As many as 50 million Americans have elevated blood pressure. The prevalence of high blood pressure increases
with age, is greater for blacks than whites, and is greater for both races in the less educated and lower
socioeconomic groups. Nonfatal and fatal cardiovascular diseases including coronary heart disease, stroke, and
renal disease. Mortality increases progressively with higher levels of both systolic and diastolic blood pressures.
Since hypertension is mostly asymptomatic and occurs in 20 to 40 percent of the population, it is essential the
General Medical Officer (GMO) is knowledgeable on how to diagnose and treat this medical condition.
(2) Therapeutic management relates to the severity of the blood pressure:
Classification
Category
Systolic BP
Diastolic BP
Recommended follow-up
Normal
<130 mmHg
<85 mmHg
Recheck in 2 years
High Normal
130 - 139
85 - 89
Recheck in 1 year
Hypertension
Stage 1 (Mild)
140-159
90-99
Confirm within 2 months
Stage 2 (Moderate)
160-179
100-109
Evaluate within 1 month
Stage 3 (Severe)
180-209
110-119
Evaluate, treat within 1 week
>210
>120
Evaluate, treat immediately
Stage 4 (Very Severe)
(a) Hypertension should not be diagnosed on the basis of a single measurement. Initially elevated
readings should be confirmed on at least two subsequent visits (unless severely elevated) over 1 to
several weeks and should reflect the patient's usual levels. The following techniques are
recommended:

The patient should be seated, arm exposed, supported, and at heart level. No smoking,
caffeine, or excessive exercise 30 minutes before measurement.

Measurement should be made 5 minutes after restful adjustment to the surroundings.

The appropriate sized cuff should be used (bladder should be at least 80 percent of the
circumference of the upper arm).

Both systolic and diastolic measurements should be made; the disappearance of sound used
for the latter.

Two or more measurements should be averaged.
(b) The clinical evaluation of patients with confirmed hypertension should help answer the following
questions:

Does the patient have primary or secondary hypertension?

Is target-organ disease present?

Are cardiovascular risk factors present in addition to high blood pressure?
(3) History, Physical Exam and Diagnostic Testing
The following is the suggested history, physical evaluation, and diagnostic testing that should be performed and
recorded on the SF 600. (It is understood that not all testing modalities may be available.)
(a) Medical History

Note the duration of elevated blood pressure, if known.

Note any symptoms from the elevated blood pressure.

Note medications used to control blood pressure with any coexistent side effects, if present.

Note any of the following risk factors:
(1) Smoking, diabetes, elevated lipids, alcohol use.
(2) Exercise history, family history of HTN.

Rule out secondary causes with significant historical negatives:
(1) Renal: history of renal trauma, infections, calculus, hematuria, proteinuria, and toxemia.
(2) Pheochromocytoma: history of paroxysms of headache, hyperhidrosis, HTN pallor,
and/or palpitations.
(3) Cushings Syndrome: central adiposity, muscle weakness, purplish striae, amenorrhea,
easy bruising, and diabetes.
(4) Hyperparathyroidism: history of calcium nephrolithiasis, proximal. muscle weakness,
psychiatric disturbances, abdominal symptoms.
(5) Hyperthyroidism: rule out this condition. (not usually associated with HTN)

Family history of polycystic kidney disease, collagen vascular disease, thyroid disease,
parathyroid disease, and HTN.

Medication history: include anabolic steroids, cocaine, decongestants, alcohol, licorice, tobacco,
birth control pills, nonsteroidal anti-inflammatory drugs (NSAIDs), appetite suppressants, and
tricyclic antidepressants.
(b) Physical Examination

Record height and weight.

Note body habitus (hypercortisolism).

Verify the blood pressure in the contralateral arm.

Fundoscopy - grade hypertensive retinopathy, if present.

Neck - listen for carotid bruits, look for distended neck veins.

Heart - increase rate, size, (laterally displaced point of maximal intensity (PMI)), clicks, murmurs,
heaves, and gallops.

Lungs - rales (congestive heart failure (CHF), wheezes (avoid beta-blockers).

Abdomen - auscultate for renal artery bruits (over flanks or to the right or left of midline just above
umbilicus), masses, enlarged kidneys, aortic dilatation, decreased femoral pulses.

Extremities - for edema, decreased peripheral pulses.

Neurologic - for paresthesias, weakness (Diabetes mellitus, hyperthyroidism, previous
cerebrovascular accident (CVA)).
(c) Laboratory Evaluation

Urinalysis - for protein, blood, and glucose. Microscopic for red blood cell (RBC) casts seen with
glomerulonephritis.

Hematocrit - increased in polycythemia vera, pheochromocytoma, obstructive sleep apnea,
decreased in renal insufficiency.

Blood sugar - diabetes, Cushings, pheochromocytoma, hyperaldosteronism.

Potassium - decreased in mineralocorticoid induced HTN.

Blood urea nitrogen (BUN) and creatinine - for renal failure.

Cholesterol, triglycerides, high density lipoprotein (HDL) for coexistent CAD risk.

Calcium - for hyperparathyroidism.

Uric acid - increased with renal disease and HTN.

Chest x-ray (CXR) - cardiomegaly, left ventricular hypertrophy (LVH), CHF, rib notching seen in
coarctation of the aorta.

Electrocardiogram (ECG) - LVH and left atrial enlargement (LAE) of HTN, and/or previous
myocardial infarction (MI).
(4) End Organ Damage
Use your history and physical examination and screening tests to determine if end organ disease is present.
(a) Cardiac:
 Coronary artery disease (chest pain, ECG).

Left ventricular hypertrophy (strain on ECG).

Left ventricular dysfunction (cardiac failure).
(b) CVA - transient ischemic attack or stroke.
(c) Vascular - absence of pulses, claudication, aneurysm.
(d) Renal.

Serum creatinine 130 umol/L.

Proteinuria (1 + or greater).

Microalbuminuria.
(e) Retinopathy - hemorrhages or exudates, with or without papilledema.
(5) Treatment
(a) The goal is to achieve and maintain blood pressure below 140/90 mmHg.
(b) Treatment includes pharmacologic and nonpharmacologic therapy.

Nonpharmacologic therapy - includes weight reduction, sodium restriction (4 to 6 gm
salt/day), alcohol in moderation only, tobacco avoidance, regular aerobic exercise, and
decreased dietary fat.

Pharmacologic therapy - In general, Beta-blockers and diuretics are preferred for initial
pharmacologic therapy because a reduction in morbidity and mortality has been demonstrated.
Angiotension converting enzyme (ACE) inhibitors, calcium channel antagonists, alpha-1
receptor blockers. The alpha-beta blockers have not been tested or shown to reduce morbidity
and mortality.
(c) If initial mono-drug therapy produces an inadequate response, increase the drug dosage, substitute
another drug, or add a second drug from a different class. If the response is still not adequate consider
adding a second drug or diuretic, if not already prescribed.
(d) Special considerations in each drug class include the following:


Thiazide diuretics

Initial treatment of choice for black hypertensive.

Use judiciously in the elderly (hypovolemia causes hip fractures).

Effect is antagonized by NSAIDS.

Cause hypokalemia, sexual dysfunction, hyperuricemia, hyperglycemia, insulin
resistance, and hypercalcemia.
Beta-blocker

Don't use if the patient has asthma, chronic obstructive pulmonary disease (COPD),
CHF, or greater than a first degree heart block.

Use cautiously if patient on a calcium channel antagonist.




May exacerbate symptoms of peripheral vascular disease.

May cause fatigue, sexual dysfunction, insomnia, etc.
Calcium channel antagonists

Use with caution if the patient has CHF.

Causes headaches, edema, and constipation.

Works well in hypertensive blacks.
ACE inhibitors

Causes a dry, nonproductive cough, hyperkalemia, and angioedema.

Can cause renal failure if the patient has bilateral renal artery stenosis.

Contraindicated in pregnancy.
Central adrenergic agents

Causes drowsiness, sedation, dry mouth, fatigue, and sexual dysfunction.

Causes rebound hypertension with abrupt cessation.
(e) The typical dose range for some commonly used antihypertensive medications are included in the
following table:
Type of drug
Usual Dosage Range
(min/max dose)
Frequency
Diuretics
Hydrochlorothizide
12.5-50 mg/day
Once daily
Furosemide
20-320 mg/dl
Twice daily
Triamterene
50-150 mg/dl
Once or twice daily
Beta blockers
Atenolol
25-100 mg
Once daily
Metoprolol
50-200 mg
Once or twice
Propanolol
40-240 mg
Twice daily
Calcium Channel antagonists
Diltiazem
90-360 mg
Three times a day
Verapamil
80-480 mg
Twice daily
Nifedepine
30-120 mg
Twice daily
ACE Inhibitors
Benzapril
10 – 40 mg
Once a day
Lisinopril
10 - 40 mg
Once a day
(f) Hypertensive emergencies or urgencies can be stabilized with:


Oral drugs.

Nifedepine 10-20 mg. every 30 minutes as needed.

Clonidine 0.1-0.2 mg. Every hour as needed up to 0.6 mg.

Captopril 25 mg. Every 1 to 2 hours as needed.

Labetalol 200-400 mg, orally every 2 to 3 hours.
Parenteral drugs

Sodium nitroprusside 0.25-10 ug/kg/min.

Hydralazine 10-20 mg.

Nitroglycerine 5-100 ug/min.
(6) Final notes
Avoid over aggressive treatment. Elevated blood pressure (without progressive end-organ damage) demands
treatment but rarely requires emergent therapy.
References
(a) The 6th Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of
High Blood Pressure. Arch Intern Med 1997; 157:2413-2444.
(b) Collins R, Peto R, MacMahon S et. al. Blood Pressure, Stroke, and Coronary Disease. Part Il: Short
Terrn Reductions in Blood Pressure. Lancet 1990; 335:827.
(c) Croog SH, Levine S, Testa MA et. al. The Effects of Antihypertensive Therapy on the Quality of Life.
NEJM, 1986;314:1657.
(d) Fletcher AK, Bulpitt CJ. How Far Should Blood Pressure Be Lowered NEJM, 1992;326:251.
(e) Houston MC. New Insights and New Approaches for the Treatment of Essential/ Hypertension. Am
Heart J.1989;117:911. 6. MacMahon SW, Peto R, Cutler J et al. Blood Pressure, Stroke, and Coronary
Heart Disease. Lancet 1990,335:765
Reviewed by LCDR B. Becker, MC, USN, Nephrology Division, Naval Medical Center Portsmouth, Portsmouth,
VA (1999).