Hypertension and its management

Vascular Problems

Hypertension

• Hypertension is one of the most common cardiovascular diseases in the world. According to WHO, hypertension is a persistent elevation of systolic blood pressure above 140mmHg and diastolic above 90mmHg, which is based on the average of two or more properly measured and seated BP readings on each of the two or more visits.
• Hypertension is sometimes called "The silent killer disease" because people who have it are often symptom free. It is a disease of vascular regulation in which the mechanisms that control arterial pressure within the normal range are altered.

Types of Hypertension

Primary types of hypertension are:

• Essential Hypertension: About 90%-95% of people with high blood pressure have essential hypertension or primary hypertension. There is no identifiable source or cause. Marked by loss of elastic tissue and arteriosclerotic changes in the aorta and larger vessels coupled with decreased caliber of the arterioles.
• Secondary Hypertension: Elevation of the blood pressure as a result of another disease such as renal parenchymal disease,Cushing's disease, pheochromocytoma, primary aldosteronism, coarctation of aorta, thyroid dysfunction, pregnancy- related conditions and medication, recreational drugs, drinks & food.

Other classifications of hypertension are:

• Isolated Systolic Hypertension: The systolic pressure rises above 140, while the lower number stays below 90 (near the normal range). This type of hypertension is most common in people over the age of 65 which is caused by the loss of elasticity in the arteries. The systolic pressure is much more important than the diastolic pressure when it comes to the risk of cardiovascular disease for an older person.
• Malignant Hypertension: It is a medical emergency as the blood pressure can suddenly rise to dangerous levels. This condition can be life threatening if not treated immediately because blood pressure quickly rises so high, a person is at risk for suffering stroke, heart attack, kidney damage. These symptoms are sometimes the first sign that an individual has high blood pressure. A person can experience shortness of breath, chest pain, an excruciating headache, vomiting, blurred vision/ blindness, seizures or even loss of consciousness as the blood pressure rises.

Risk factors

• Non-Modifiable Risk factors
  • Positive family history.
  • Age: primary hypertension typically appears between the age of 30-50 years. More common in men over 35, women over 45 years.
  • Gender: hypertension is higher in men than in women until 55-years. Between the age 55-74years, the risk in men and that in women are almost equal and after 74years, women are at greater risk.
  • Ethnicity: African- American men are affected twice as often as white men/women.
• Modifiable risk factors
  • Stress.
  • Obesity.
  • Nutrition: A high salt diet.
  • Substance use.

Pathophysiology

• Most of the mechanisms associated with secondary hypertension are generally fully understood. However, those associated with essential hypertension are far less understood.
• What is known is that cardiac output is raised early in the disease course, with total peripheral resistance (TPR) normal; over time cardiac output drops to normal level but TPR is increased.

Signs and Symptoms

• Palpitation, excessive perspiration,
• Angina and dyspnea, anxiety,
• Dizziness, buzzing in ears,
• Reduced activity tolerance,
• Fatigue, tiredness.

Advance disease may produce symptoms:

• Early morning headache,
• Blurred vision/Papilledema,
• Spontaneous nose bleeding,
• Depression, Renal Changes,
• Coronary artery disease: stroke.
• Complications of hypertension include MI, stroke, hear failure, retinopathy, nephropathy etc.

Diagnosis

• Health History,
• Physical Examination,
• Laboratory Test: lipid profile, RFT, LFT,
• ECG, chest x-ray, USG and other imaging stud according to the complain and choice of the patient.

Management

The goal of medical management is to prevent death complications by achieving / maintaining the BP 140/90 mmHg or lower.

The medical management includes following:

• Lifestyle Modification: Healthy eating, reducing dietary sodium and alcohol intake, cessation d smoking, regular physical activity and achieving healthy body weight are all effective in lowering the blood pressure.
• Antihypertensive Drug Therapy.

Initial drug choices

• Stage I HTN: SBP 140-159 or DBP 90-99

Thiazide based diuretics as the first line of Angiotensin converting enzyme inhibitor (ACE-I)is used as a first line drug.

• Stage II HTN: Majority of people need more than one drug therapy to control HTN.
• Thiazide type diuretics + ACEI or CCB or BB Other drugs such as, CCB, BB, diuretics etc are also used as the combination of drugs.
• Calcium channel blockers such as nifedipine (Adalat) amlodipine verapamil are used to stop the movement of (Norvasc), diltiazem, calcium into the cells; relax smooth muscle, which causes vasodilation and inhibit reabsorption of sodium in the renal tubules.
• Diuretics:e.g. bendroflumethiazide. chlorthalidone, hydrochlorothiazide, lower BP by promoting urinary excretion of water and sodium to lower blood volume.
• Additional diuretics such a furosemide or low- dosages of spironolactone may be used Alpha blockers such as prazosin, or terazosin are used to dilate peripheral blood vessels and to lower peripheral vascular resistance.
• ACE inhibitors such as captopril, enalapril, monopril, lisinopril(Zestril), quinapril, ramipril (Altace) are used. It works by blocking the enzyme that converts angiotensin I to angiotensin II. These drugs also raise the level of bradykinin, a potent vasodilator and lower aldosterone level
• Angiotensin II receptor antagonist may be used where ACE inhibitors are not tolerated: e.g., telmisartan(Micardis, Pritor),irbesartan (Avapro), losartan(Cozaar),valsartan(Diovan), candesartan(Amias), olmesartan(Benicar, Olmetec)
• Beta blockers such as atenolol, labetalol, metoprolol (Lopressor, Toprol-XL), propranolol are used to slow the heart rate and reduce cardiac output as well as block the effect of epinephrine.
• Either diuretics or beta blockers for non complicated HTN in low dose is used. If BP does not fall than 140/90 mm of Hg, the dose is increased.

Nursing Assessment

• History
  • Family history of HTN, previous episodes of high BP excessive salt intake, lipid abnormalities, cigarette smoking,
  • Episodes of headache, weakness, muscle cramp, tingling, palpitations, disturbances sweating, visual disturbances,
  • Medications: NSAIDs, Oral contraceptive pills, steroids,
  • Other disease processes such as gout, DM, Asthma.
• Physical examination: heart rate, respiration, peripheral pulse and funduscopic examinations
  • Measure the BP of the patient under the same conditions each time,
  • Avoid taking BP readings immediately after stressful situations.

Nursing Diagnosis

• Deficient knowledge regarding the treatment regimen and control of BP,
• Noncompliance with therapeutic regimen related to side-effect of prescribed therapy,
• In-effective health maintenance.

Nursing Interventions

The main objective of nursing intervention is to lower the BP without adverse effect. Nursing interventions are focused on self care and treatment adherence.

• Record baseline BP in three positions (lying, sitting, standing) and in both arms.
• Continuously
  • Provide basic education regarding cause, risk factors, complications and management of HTN.
  • Explain the patient that the goal of treatment is to control BP, reduce possibility of complications and use the minimum number of drugs with lowest dosage necessary to accomplish this.
  • Educate the patient to be aware of toxic manifestations and report them so that adjustments can be made; be aware that BP is decreased when circulating blood volume is reduced - dehydration, diarrhoea and haemorrhage.
• Encourage self management by directing lifestyle modification such as decreasing sodium intake, saturated fat (animal source, fried foods, fast foods) and increase food containing fruits, vegetables.
• Teach the patient to quit smoking, avoid alcohol intake, avoid consuming saturated fat, get regular physical examination of eyes, kidneys, control blood glucose level, have prescribed medications and monitor the side effects of medications.
• Maintain the intake of K+, calcium and magnesium (fruit & vegetable); associated with decrease risk of HTN.
• Explain about the importance of regular medication and lifestyle modifications.
• Maintain the intake of K+, calcium and magnesium (fruit & vegetable); associated with decrease risk of HTN.
• Manage stress: meditation, biofeedback, these methods may work by decreasing the daily release of epinephrine & nor epinephrine by the adrenal medulla.
• Regular exercise and reduction of weight if obese.Two classes of hypertensive crisis that requires immediate intervention:
• Hypertensive Emergency: It is a situation in which BP is extremely elevated (more than 180/120 ) and must be lowered immediately (not necessary to less than 140/90 ) to halt or prevent damage to the target organs (heart, brain, kidneys, eyes)