Managed care presents challenges to the cost-effective utilization of nurse practitioners as primary care providers, particularly in terms of ensuring access, choice, and continuity of care. With the growing need for primary care providers and multiple ailments of our aging community, nurse practitioners can close the gap where patients are in dire need for improved quality of care that is readily available.
Ailments present in individuals with undiagnosed pulmonary hypertension (PH), often go to their provider complaining of shortness-of-breath and unusual tiredness. These are vague symptoms that are associated with many different disorders, both mental and physical. If a person is overweight or getting a bit older, their provider may tell them to lose some weight and get more exercise. Their symptoms may also be confused with asthma, depression or countless number of other disorders. PH is a fairly rare disorder that is often not suspected until all other possible causes for the symptoms have been ruled out. It often is not until the actual red-flag warning symptoms of heart failure, such as edema (water buildup in the legs and/or the rest of the body), severe shortness-of-breath, fainting and/or actual damage to the heart become readily apparent that the diagnosis is even considered. For many, PH may be present for years before it is properly diagnosed (PHCentral, 2010).
What is Pulmonary Hypertension?
PH is a rare lung disorder in which the arteries that carry blood from the heart to the lungs become narrowed, making it difficult for blood to flow through the vessels. Scientists believe that the process starts with injury to the layer of cells that line the small blood vessels of the lungs. This injury, which occurs for unknown reasons, may cause changes in the way these cells interact with the smooth muscle cells in the vessel wall. As a result, the smooth muscle contracts more than normal and narrows the vessel. The blood pressure in these arteries, called pulmonary arteries, rises far above normal levels. This abnormally high pressure strains the right ventricle of the heart, causing it to expand in size. Overworked and enlarged, the right ventricle gradually becomes weaker and loses its ability to pump enough blood to the lungs. This could lead to the development of right heart failure (The Cleveland Clinic Foundation, 2010).
Clinical Presentation
Symptoms of PH do not usually occur until the condition has progressed. The first symptom of PH is usually shortness of breath with everyday activities, such as climbing stairs. Fatigue, dizziness, and fainting spells also can be symptoms. Swelling in the ankles, abdomen or legs; bluish lips and skin, and chest pain may occur as strain on the heart increases. Symptoms range in severity and a given patient may not have all of the symptoms.
In more advanced stages of the disease, even minimal activity will produce some of the symptoms. Additional symptoms include irregular heart beat (palpitations or strong, throbbing sensation), racing pulse, passing out or dizziness, progressive shortness of breath during exercise or activity, and difficulty breathing at rest. Eventually, it may become difficult to carry out any activities as the disease worsens (The Cleveland Clinic Foundation, 2010).
Causes of Pulmonary Hypertension
The diet drug "fen-phen." Although the appetite suppressant "fen-phen" (dexfenfluramine and phentermine) has been taken off the market, former fen-phen users have a 23-fold increase risk of developing PH, possibly years later.
Liver diseases, rheumatic disorders, lung conditions. PH also can occur as a result of other medical conditions, such as chronic liver disease and liver cirrhosis; rheumatic disorders such as scleroderma or systemic lupus erythematous (lupus); and lung conditions including tumors, emphysema, chronic obstructive pulmonary disease (COPD), and pulmonary fibrosis.
Certain heart diseases. Heart diseases including aortic valve disease, left heart failure, mitral valve disease, and congenital heart disease can also cause PH.
Thromboembolic disease. A blood clot in a large pulmonary artery can result in the development of PH.
Low-oxygen conditions. High altitude living, obesity, and sleep apnea can also lead to the development of PH.
Genetic predisposition. PH is inherited in a small number of cases. Knowing that someone in the family had or has PH should prompt early evaluation should symptoms occur.
PH may also be caused by other conditions, and in some cases, the cause is unknown (The Cleveland Clinic Foundation, 2010).
Differential Diagnoses
Differential diagnoses include sleep apnea, cardiogenic pulmonary edema, dilated cardiomyopathy, pulmonary embolism, cor pulmonale, pulmonary hypertension, secondary hypothyroidism, pulmonic stenosis, mitral stenosis, scleroderma, mixed connective-tissue disease, systemic lupus erythematosus and portal hypertension (Medscape, 2010).
Those at Risk for Pulmonary Hypertension
The exact number of people who have PH isn't known. Group 1 pulmonary arterial hypertension (PAH) without a known cause is rare. PH that occurs with another disease or condition is more common.
Anyone can develop PH. However, PAH that has no known cause affects about two to three times as many women as men. PH usually develops between the ages of 20 and 60, but it can occur at any age. "Application of Erikson's stages of psychosocial development helps in analyzing patient's symptomatic behavior in the context of traumatic past experiences and struggles with current developmental tasks" (Current Nursing, 2010).
"People who are at increased risk for PH include those who have a family history of the condition. Also are those who have certain diseases or conditions, such as heart and lung diseases, liver disease, HIV infection, or blood clots in the pulmonary arteries. People who use certain diet medicines or street drugs (such as cocaine) are as well at risk" (National Heart, Lung and Blood Institute [NHLBI], 2008).
How Pulmonary Hypertension is Diagnosed
Because PH may be caused by many medical conditions, a complete medical history, physical exam, and description of symptoms are necessary to rule out other diseases and make the correct diagnosis. "Complete blood count is usually normal in PH but may show secondary polycythemia. Arterial blood gases show low PO2 and oxygen saturation. Overnight oximetry and sleep study to rule out sleep apnea or hypopnea. Other blood tests: antinuclear antibody (ANA), antineutrophil cytoplasmic antibodies (ANCA), and rheumatoid factor (RF) to screen for underlying connective tissue disease, HIV serology, liver function tests, and antiphospholipid antibodies. Ventilation perfusion lung scan has high sensitivity for chronic thromboembolic PH. The diagnosis should be confirmed by pulmonary angiography, which has high specificity (Ferri, 2011, p. 914).
Treatment for Pulmonary Hypertension
It often takes some time to find the best treatment for PH. The treatments are often complex and require extensive follow-up care. The provider may also need to change treatments if it's no longer effective. When PH is caused by another condition, the provider will treat the underlying cause whenever possible.
Medications
Blood vessel dilators (vasodilators). Vasodilators open narrowed blood vessels. One of the most commonly prescribed vasodilators for PH is epoprostenol (Flolan). The drawback to epoprostenol is that its effects last only a few minutes. This drug is continuously injected through an intravenous (IV) catheter via a small pump that is worn in a pack on a belt or on the shoulder. The patient will learn to mix his own medication mixture, operate the pump and care for the IV catheter. Comprehensive follow-up care will be needed. Potential side effects of epoprostenol include jaw pain, nausea, diarrhea, leg cramps, as well as pain and infection at the IV site.
Another form of the drug, iloprost (Ventavis), avoids many of these problems. Iloprost can be inhaled every three hours through a nebulizer, a machine that vaporizes medication, making it far more convenient and less painful to use. And because it's inhaled, it goes directly to the lungs. Side effects associated with iloprost include chest pain - often accompanied by headache and nausea - and breathlessness.
Endothelin receptor antagonists. These medications reverse the effect of endothelin, a substance in the walls of blood vessels that causes them to narrow. One of these medications, bosentan (Tracleer), may improve energy level and symptoms. The drug isn't for pregnant women. If bosentan is taken, there will be a need for monthly liver monitoring, because the drug can damage the liver.
Sildenafil. Revatio (sildenafil) is sometimes used to treat PH. It works by opening the blood vessels in the lungs to allow blood to flow through more easily. Side effects include dizziness and vision problems.
High-dose calcium channel blockers. These drugs help relax the muscles in the walls of blood vessels. They include medications such as amlodipine (Norvasc), diltiazem (Cardizem, Tiazac) and nifedipine (Adalat, Procardia). Although calcium channel blockers can be effective, only a small number of people with PH respond to them.
Ambrisentan. Ambrisentan (Letairis) is another medication that stops the narrowing of blood vessels. This drug can cause serious liver damage if not taken appropriately, and it shouldn't be taken by pregnant women. Before taking the drug, the provider should know about any preexisting liver condition.
Anticoagulants. The provider is likely to prescribe the anticoagulant warfarin (Coumadin) to help prevent the formation of blood clots within the small pulmonary arteries. Because anticoagulants prevent normal blood coagulation, they increase the risk of bleeding complications. Take warfarin exactly as prescribed, because warfarin can cause severe side effects if taken incorrectly. If taking warfarin, the provider will ask you to have periodic blood tests to check how well the drug is working. Many other drugs, herbal supplements and foods can interact with warfarin, so be sure the provider knows all of the medications taken.
Diuretics. Commonly known as water pills, these medications help eliminate excess fluid from the body. This reduces the amount of work the heart has to do. They also may be used to limit fluid buildup in the lungs.
Oxygen. The provider may suggest to sometimes breathe pure oxygen, a treatment known as oxygen therapy, to help treat PH, especially if living in high altitudes or have sleep apnea. Some people with PH eventually require constant oxygen therapy.
Surgeries
Atrial septostomy. If medications don't control PH, this open-heart surgery may be an option. In an atrial septostomy, a surgeon will create an opening between the left and right chambers of the heart to relieve the pressure on the right side of the heart. Atrial septostomy can have serious complications, including heart rhythm abnormalities (arrhythmias).
Transplantation. In some cases, a lung or heart-lung transplant may be an option, especially for younger people who have idiopathic PH. Major risks of any type of transplantation include rejection of the transplanted organ and serious infection, and immunosuppressant drugs must be taken for life to help reduce the chance of rejection (Mayo Clinic, 2010).
Health Promotion and Teaching Plan, Disease Prevention
Although medical treatment can't cure PH, it can lessen symptoms. Here are some lifestyle changes to educate patients on how to improve their condition:
1. Get plenty of rest. Resting can reduce the fatigue that may come from having PH.
2. Stay as active as possible. Even the mildest forms of activity may be too exhausting for some people with PH. For others, moderate exercise such as walking may be beneficial, and using oxygen during exercise may be especially helpful. But first, talk to your provider about specific exercise restrictions. In most cases, it's recommended that you not lift more than 50 pounds (22.7 kilograms). Your provider can help you plan an appropriate exercise program.
3. Don't smoke. If you smoke, the most important thing you can do for your heart and lung health is to stop. If you can't stop smoking by yourself, ask your provider to prescribe a treatment plan to help you quit. Also, avoid secondhand smoke if possible.
4. Avoid becoming pregnant or using birth control pills. If you're a woman of childbearing age, avoid becoming pregnant. Pregnancy can be life-threatening for both you and your baby. Also avoid using birth control pills, which can increase your risk of blood clots. Talk to your provider about alternative forms of birth control.
5. Avoid traveling to or living at high altitudes. High altitudes can worsen the symptoms of PH. If you live at an altitude of 8,000 feet (2,438 meters) or higher, your provider may recommend that you move to a lower elevation.
6. Avoid situations that can excessively lower blood pressure. These include sitting in a hot tub or sauna or taking long hot baths or showers. These activities lower your blood pressure and cause fainting or even death. You should also avoid activities that cause prolonged straining, such as lifting heavy objects or weights.
7. Find ways to reduce stress. These can range from yoga, meditation and biofeedback to warm baths, music or a good book. Try to allow at least 30 minutes a day for an activity you find relaxing. Many people with PH find that simply reducing stress can greatly improve the quality of their lives.
8. Follow a nutritious diet and stay at a healthy weight. It's likely your provider will recommend limiting the amount of salt in your diet to minimize swelling of your body's tissues (edema). Most experts agree that you should eat no more than 1,500 to 2,400 milligrams of salt a day. Keep in mind that processed foods often are high in salt, so it's important to check labels carefully (Mayo Clinic, 2010).
Clinical Management Based on Evidence Based Practice
"In some patients with pulmonary arterial hypertension, the addition of sildenafil to long-term intravenous epoprostenol therapy improves exercise capacity, hemodynamic measurements, time to clinical worsening, and quality of life, but not Borg dyspnea score. Increased rates of headache and dyspepsia occurred with the addition of sildenafil.
Pulmonary arterial hypertension is a chronic debilitating disease without a cure. Current therapies include prostacyclines, endothelin receptor antagonists, and phosphodiesterase 5 inhibitors. Monotherapy with these drugs is effective in increasing exercise capacity and improving hemodynamics, but is still far from being satisfactory. There have been a number of small studies and two randomized trials with two drugs, neither with sildenafil. Although there have been a number of small trials with sildenafil as the single agent or as added to another drug, this trial is the first, large, randomized, placebo-controlled trial where sildenafil is added as a second drug in patients stabilized on an optimal dose of epoprostenol. The patients were symptomatic with 72% being New York Heart Association (NYHA) class III-IV. The dose of sildenafil was gradually increased over the 16-week course and showed, consistent with smaller, nonrandomized studies, that exercise capacity was increased but only in those whose baseline 6-minute walk distance was >325 m. In those whose baseline exercise capacity was <325 m, there was no improvement when sildenafil was added. The hemodynamic benefits in lowering pulmonary artery pressure and vascular resistance, and increasing cardiac output were small but significant. Even though the 6-minute distance was longer, the Borg dyspnea score was the same, suggesting that patients on both drugs could walk farther than those on epoprostenol alone but had the same degree of perceived exertion. One of the most important findings in this study is that the time to clinical worsening events in the group taking both drugs was increased. Because this was only a 16-week trial, certain etiologies of pulmonary artery hypertension such as HIV and unoperated congenital heart disease were not included, and sildenafil was added to stabilized patients already on epoprostenol, these findings should be confined to the population included in this study. A long-term study is needed to see if there is mortality (Ferri, 2011, p. 916).
Future Treatments
Serotonin receptor modulators, platelet-derived growth factor, Rho kinase inhibitors and potential of cardiac MRI in assessment of RV function (Ferri, 2011, p. 916). Refinement in noninvasive diagnostic studies, including imaging techniques and biomarkers that are not only specific for the presence of PH but sensitive to changes in the clinical status and may therefore also be useful as markers of severity (McGoon et al., 2004, p. 28S-29S).
Evaluation Criteria and Time Frame
Patients with PH require ongoing monitoring of their medication dosages and screening for side effects. For instance, intravenous epoprostenol has been associated with a number of adverse effects that should be monitored for, and patients receiving bosentan require liver function tests before therapy is started and monthly thereafter. As long as patients are on therapy, they will need to be evaluated every 2 to 3 months for clinical examination and a 6-minute walk test. Echocardiography and right heart catheterization are performed every 6 and 12 months, respectively, as long as patients are progressing as expected (Mughal, Mandell, James, Stelmach, & Minai, 2003, p. S33). Proper referrals to a pulmonologist, cardiologist and sometimes rheumatologist will be necessary.
Summary
A high level of suspicion is very important for the diagnosis of PH, regardless of the underlying cause. Once suspected, a methodical workup using commonly implemented diagnostic interventions allows both validation of the presence of PH and explanation of its etiology. Clarification of etiology is necessary to ensure that the proper therapeutic interventions are applied. A diagnostic algorithm that is accepted among experienced centers can guide the evaluation of PH. Like all guidelines, the algorithm may be modified according to specific clinical circumstances. Most patients receive a diagnosis as a result of evaluation for symptoms, while some diagnoses are made during screening of asymptomatic populations at risk. Our vigorously escalating understanding of the core pathophysiology of PH, together with effective treatments, will likely lengthen life expectancy and increase those living with PH quality of life.
