Hypertension can lead to several atherosclerotic cardiovascular diseases (ASCVD) which can result in events like heart attacks, deep vein thromboses (DVT), and strokes. It retains its reputation as a leading cause of morbidity and mortality in the United States and throughout the world.

Hypertension generally refers to the constriction of the veins resulting in reduced return of blood to the heart. The heart responds by increasing its rate and the force of its contractions which ultimately leads to increased blood pressure throughout the body.

As blood pressure becomes chronically elevated, it eventually leads to organ damage increasing the risk of ASCVD events like heart attacks and strokes.

When evaluating blood pressure, it is important to understand some basic terminology. The average blood pressure of a healthy adult should usually read somewhere around 120/80 mmHg.

The top number is the systolic pressure which refers to the pressure created by the contraction of the ventricles in the heart. The bottom number is diastole, which refers to the heart’s relaxation and blood’s return through the veins.

Once hypertension is diagnosed health care provider (HCP) will grade the severity of the disease based on accepted values established by the 2019 ACC/AHA guidelines. The stage of hypertension a client presents with will then determine their pharmacological therapy if needed.

In addition to medicinal treatments, clients should also be screened for any underlying causes of their hypertension that can be modified to improve their overall health. Once the contributing factors are identified a client should be provided a consultation on what lifestyle choices. They can change to optimize their treatment and improve their overall health.

Causes of Hypertension

Among the many potential contributing factors leading to hypertension, there are several aspects of the disease that cannot be controlled through lifestyle changes. Family history plays a significant role in determining the risk of developing hypertension. Clients with family histories of men under the age of 55 or women under the age of 65 increases their risk of high blood pressure as well as premature ASCVD events.¹

Blood pressure also tends to increase over time as we age which is compounded by other common comorbidities such as chronic kidney disease, diabetes, metabolic syndrome, and high cholesterol. Lastly, ethnicity can play a role in causing hypertension as data demonstrates that clients of African American or South Asian descent are at increased risk of developing high blood pressure.¹

Many potential causes can be addressed to reduce a client’s blood pressure without pharmacological treatment. Dietary modifications with the intent to establish a heart-healthy lifestyle are key interventions to provide to clients. Clients should also be advised to increase their exercise to a least 150 minutes a week of moderate-intensity workouts or 75 minutes a week of vigorous-intensity aerobic activity.¹

Clients who cannot meet these requirements should still be advised to engage in some moderate-vigorous physical activity even if it’s less than the recommended amount.¹ Clients who are overweight should also be encouraged to utilize diet and exercise modifications to reduce their body mass to appropriate levels.

Among the various dietary interventions, a key one to consider involves sodium intake throughout the day. Since sodium can lead to increased blood pressure it is important to restrict their intake to a healthy level whenever possible. Specific sodium restrictions as well as other dietary modifications will be addressed later in the nursing interventions section.

Signs and Symptoms of Hypertension

Hypertension has famously been dubbed the “silent killer” among the leading diseases in morbidity and mortality. This is because clients who present with high blood pressure will often present without any symptoms. Instead their hypertension may be discovered after an ASCVD event that could have been prevented with therapy.

Clients who do observe signs and symptoms of hypertension may present with complaints of dizziness, headaches, chest pain, or blurry vision. In some cases, these symptoms may relate to the severity and duration of their high blood pressure leading to systemic changes.

Hypertension Pathophysiology

When a client is newly diagnosed with hypertension a clinician will be assigned the task of staging the client which will determine their treatment avenues. Currently, the ACC/AHA guidelines designate clinical hypertension as 130-139/80-89 mmHg, which is also stage 1 hypertension. Stage 2 hypertension are blood pressure measurements greater than 140/90 mmHg.

It’s important to note that a clinician should avoid diagnosing a client with hypertension in a single visit as a client’s blood pressure could just be acutely elevated. Usually, clinicians do not stage and diagnose hypertension until they perform two or more readings on at least two separate visits.

On rare occasions a client may present with a blood pressure greater than 180/120 mmHg, which is defined as a hypertensive crisis. When a client presents with this reading it is imperative to alert a physician immediately to evaluate their condition.

Clients in hypertensive crisis are at an increased risk of experience an ASCVD event such as a heart attack or stroke. As a result, they need to be put on blood pressure medications as soon as possible to reduce their risk of having a serious health event.

Hypertension Treatment

Pharmacology of Hypertension

For clients with stage 1 hypertension, clinicians should screen their clients with an ASCVD risk calculator which determines the risk of having an ASCVD event within the next ten years.

Clients with an ASCVD risk score of less than 10 % without a history of ASCVD events (e.g. stroke, MI, DVT) should first be treated with nonpharm interventions, then reassessed in three to six months. Clients with stage 1 hypertension who did not meet that criteria or stage 2 hypertension should be initiated on BP-lowering medications in addition to nonpharm.

ACEi/ARB: ACE inhibitors and ARBs prove to be extremely common blood pressure medications in practice today. They work by inhibiting the effects of angiotensin II which ultimately leads to lower arteriolar resistance, decreased cardiac output, and increased blood flow to vital organs such as the kidneys.

• ACE inhibitors includes drugs that have the suffix “pril” which includes medications like lisinopril, ramipril, benazepril, and quinapril. Although ACE inhibitors are generally well tolerated – dry cough proves to be a very common adverse effect of medications in this class which often leads to discontinuation or poor adherence.
• ARBs work a bit differently from ACE inhibitors as it works through slightly different pathways. The effects and efficacy are relatively the same, but ARBs are not associated with the dry cough side effect unlike like ACE inhibitors. Clients are commonly switched from ACE inhibitors to ARBs upon the development of that side effect. The ARB class contains medications that use the suffix “sartan”, examples of ARBs includes losartan, candesartan, valsartan, and olmesartan.

Diuretics: Diuretics prove to be among the oldest hypertension treatments available today. They work by increasing the excretion of fluids from the body which leads to reduced blood pressure. There are several different classes of diuretics which can lead to different side effects dealing primarily with electrolyte imbalance.

• Thiazide diuretics: Thiazide diuretics work on the distal renal tubule in the nephron of the kidney. These medications are associated with the “thiazide” suffix, some examples include hydrochlorothiazide and chlorothiazide – other examples not using the suffix includes chlorthalidone, indapamide, and metolazone.
• Loop diuretics: Loop diuretics are potent diuretics often prescribed for the treatment of edema. They work in the proximal and distal tubules in the nephron and cause significant increases in urine output. Examples of loop diuretics includes furosemide, torsemide, and bumetanide.
• Potassium sparring diuretics: Unlike the other diuretics mentioned so far potassium sparring diuretics work on a different part of the nephron which ultimately achieves the same effect without potassium loss. Examples of these diuretics includes triamterene and amiloride.
• Another class of diuretics that shares this effect are called aldosterone antagonists which do not cause potassium loss but also has effects on aldosterone production which creates alternative indications for these medications. Examples of aldosterone antagonists includes spironolactone and eplerenone.

Calcium channel blockers: Calcium channel blockers can decrease blood pressure by decreasing the influx of calcium into the smooth muscle of the vasculature ultimately causing them to relax. There are two different types of calcium channel blockers which distinguishes their effects.

Dihydropyridines are the more commonly used kind of calcium channel blocker. Examples of them include amlodipine, nifedipine, a nicardipine. These medications do not influence the calcium channels in the heart and therefore works primarily in the vasculature to reduce blood pressure. Clients should be counseled on the possibility of developing edema with these medications as they do not influence urine output.

Non-dihydropyridines are the other kinds of calcium channel blockers that do affect the calcium channels in the heart. Examples of these include verapamil and diltiazem which work to both decrease blood pressure and heart rate. Non-dihydropyridines are generally reserved for clients with heart conditions as a result of this effect.

Beta blockers: Beta blockers work by inhibiting the effects of the beta 1 receptors on the heart which leads to decreased heart rate and cardiac output and ultimately blood pressure. Beta-blockers may not be selective to the beta 1 receptor which can become problematic for asthmatic clients as beta 2 antagonism can cause constriction of the airways in the lungs. Examples of beta 1 selective medications includes atenolol, metoprolol, bisoprolol, and nebivolol. Non-selective examples include labetalol, propranolol, and sotalol.

Beta blockers are often not the first choice for newly diagnosed hypertensive clients, but they are very beneficial for clients experiencing heart failure or arrythmia as it can reduce the stress of beating on the heart. Beta-blockers can lower the energy of a client by reducing their heart rate. As a result, they should be advised to take physical activity easy for the first week or two of therapy.

The last important consideration is to counsel clients with beta-blockers who are diabetic. This is because these medications can mask the symptoms of hypoglycemia. Therefore, clients who are diabetic and at risk of hypoglycemia should be careful using this medication.

Nursing Interventions for Hypertension

There are several key nursing interventions to keep in mind when treating clients with hypertension. A key recommendation for clients with uncontrolled hypertension is to measure their blood pressure regularly. By frequently measuring blood pressure they can help clinicians with their medicinal selections as well as dosage.

When reading blood pressure, the client should be resting for approximately five minutes prior to the reading. It’s important to keep contributing factors to acute high blood pressure in mind such as recent alcohol use, nicotine use, or caffeine.

Clients with uncontrolled hypertension should be consulted on maximizing their adherence to their treatments. In addition to optimal adherence, several lifestyle modifications can be made to optimize a client’s health.

• Sodium restriction: The ACC/AHA guidelines recommend that clients with hypertension aim for a goal of < 1500 mg per day of sodium – or at least reduction of 1000mg per day. By restricting sodium clients can achieve up to a 5mmHg reduction in blood pressure. Clients should be educated on how to measure their daily salt intake and provide them with alternatives to salt in their meals throughout the day.
• Weight loss: Weight loss is a key recommendation to offer to clients who are overweight or obese as even minimal reductions can have substantial impacts. The ACC/AHA guidelines suggest that a 1 kg reduction in body weight can lead to approximately 1 mmHg decrease in BP.
• Potassium management: Since clients with hypertension will be likely treated with medications that result in potassium loss, clients should be advised to increase their potassium intake per the discretion of their HCP “health care provider”. The recommendation is to consume 3500-5000 mg per day of potassium preferably by consumption of potassium rich foods. If a client cannot achieve adequate potassium levels despite dietary modifications, they may need to receive supplementation.
• Physical activity: Exercise has been widely studied in the field of hypertension as the data almost overwhelmingly supports increasing physical activity to improve a client’s blood pressure. Clients should be advised to try and get 90-150 minutes of aerobic exercise per week. Strength training is also recommended to improve overall health as well as blood pressure – however aerobic exercise appears to be the most effective at reducing blood pressure.
• Alcohol consumption: Excessive alcohol consumption is associated with increased blood pressure. Clients should be advised to reduce their drink consumption to < 2 drinks/day for men and < 1 drink/day for women. Alcohol restriction can result in a drop of 4 mmHg in blood pressure.
• Smoking cessation: Nicotine consumption is associated with an acute increase in blood pressure – but does not increase blood pressure in the long term. Nevertheless, tobacco use increases the risk of all-cause mortality contributing towards and increased risks of ASCVD events. Clients with hypertension who smoke should be provided resources including nonpharm and pharmacological therapy to get them to quit.

Hypertension Conclusion

Hypertension currently remains among the top leaders in mortality and morbidity throughout both the United States and the world. It has appropriately earned the name the “silent killer” due to the lack of symptoms that a client may exhibit. As a result, it is imperative that all clients get screened for hypertension especially as they age.

It’s important that clients receive treatment for high blood pressure as it can prevent the occurrence of many serious health events including but not limited to heart attacks and strokes.

References

1. Addendum to: 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease: Executive Summary. Journal of the American College of Cardiology. 2019. doi:10.1016/j.jacc.2019.03.015.
2. Micromedex Solutions. Truven Health Analytics, Inc. Ann Arbor, MI. Available at: http://www.micromedexsolutions.com. Accessed September 9, 2019.