pulmonary hypertension
Pulmonary Hypertension
Definition
Description
- Primary pulmonary hypertension. The cause of pulmonary hypertension is unknown. It is rare, affecting one people per-million. The illness most often occurs in young adults, especially women.
- Secondary pulmonary hypertension. Secondary pulmonary hypertension is increased pressure of the blood vessels of the lungs as a result of other medical conditions.
Causes and symptoms
Diagnosis
Treatment
Prognosis
Prevention
Key terms
Resources
Organizations
Other
pul·mo·nar·y hy·per·ten·sion
pulmonary hypertension
An idiopathic condition more common in women age 20 to 40, which is characterised by increased pulmonary arterial blood pressure in absence of other heart or lung disease. The major effect of pulmonary hypertension is increased right ventricular load which, when prolonged, predisposes patients to right ventricular failure, syncope, precordial pain, sudden death.Types
Idiopathic, secondary to Eisenmenger’s complex, respiratory failure in cystic fibrosis and COPD, with inhibition of endothelium-dependent pulmonary arterial relaxation due to decreased synthesis of nitric oxide or endothelium-derived growth factor.
Management
High-dose calcium channel blockers may induce decreased pulmonary artery pressure and pulmonary vascular resistance, which may be combined with warfarin.
Causes of death
Arrhythmias, right and left ventricular dysfunction, left main coronary artery compression, dissection of pulmonary artery.
Prognosis
The average lifespan post-diagnosis is 3 years without therapy. The prognosis is worse in those who have severe symptoms, are older than 45 when diagnosed, present with right-sided heart failure, and do not respond to treatment.
Pulmonary hypertension aetiology
Decreased cross-sectional area of the pulmonary vascular bed:
• Parenchymal lung diseases;
• Lung resection;
• Congenital hypoplasia.
Increased flow through the pulmonary arteries:
• Systemic to pulmonary shunts.
Increased resistance to flow through large pulmonary arteries:
• Chronic thromboembolic disease;
• Takayasu’s arteritis;
• Congenital pulmonary artery stenosis;
• Mediastinal processes (fibrosis, tumours);
• Pulmonary artery tumours.
Increased resistance to flow through small pulmonary arteries:
• Primary pulmonary arterial hypertension;
• Pulmonary vasculitides;
• Autoimmune diseases;
• Chemical/toxic damage;
• Increased resistance to pulmonary venous drainage.
Increased resistance to pulmonary venous drainage:
• Elevated left ventricular diastolic pressure;
• Elevated left atrial pressure;
• Pulmonary venous obstruction.
Chronic alveolar hypoxia
• Obesity-hypoventilation syndrome;
• Chest wall disorders;
• Neuromuscular disorders;
• Parenchymal lung disease.
Miscellaneous conditions:
• High altitude;
• Portopulmonary hypertension;
• HIV infection;
• Sickle haemoglobinopathies;
• Pulmonary capillary hemangiomatosis.
Pulmonary Hypertension types
Passive
Systemic congestion due to mitral stenosis, left ventricular failure, left atrial myxoma, anomalous drainage of the pulmonary circulation.
Hyperkinetic
Due to increased blood flow through lungs secondary to congenital heart defects.
Vaso-occlusive
Due to recurring vessel obstruction, seen in IV drug abuse and patients associated with hypoxia, alveolar hypoventilation (mitral stenosis, coarctation of aorta, Eisenmenger’s complex, ventricular septal defect).
Secondary
Comprises 10-20% of cases, treated by addressing the underlying disease—e.g., unilateral renal artery stenosis, coarctation of aorta, primary aldosteronism, pheochromocytoma.
pulmonary hypertension
Idiopathic pulmonary hypertension, primary pulmonary hypertension Internal medicine An idiopathic condition more common in ♀ age 20 to 40 characterized by ↑ blood pressure in pulmonary arteries in absence of other heart or lung disease; the major effect of PH is ↑ right ventricular load which, when prolonged, predisposes Pts to right ventricular failure, syncope, precordial pain, sudden death Types Idiopathic, 2º to Eisenmenger's complex, respiratory failure in cystic fibrosis and COPD, with inhibition of endothelium-dependent pulmonary arterial relaxation due to ↓ synthesis of nitric oxide or endothelium-derived growth factor Prognosis No longer thought to be universally fatal Treatment High-dose CCBs may induce ↓ pulmonary artery pressure and pulmonary vascular resistance, which may be combined with warfarinpul·mo·nar·y hy·per·ten·sion
(pul'mŏ-nar-ē hī'pĕr-ten'shŭn)pulmonary hypertension
Abnormally high blood pressure in the arteries supplying the lungs. This occurs if the resistance to blood flow though the lungs is increased, as by PULMONARY FIBROSIS, so that the heart has to pump more strongly. Pulmonary hypertension causes the right side of the heart to enlarge and perhaps, eventually to fail. Endothelin-1 is known to have an important role in the disease.Pulmonary Hypertension
| DRG Category: | 315 |
| Mean LOS: | 4 days |
| Description: | MEDICAL: Other Circulatory System Diagnoses With CC |
Pulmonary hypertension is diagnosed when the systolic pressure in the pulmonary artery exceeds 30 mm Hg. It is most commonly seen in preexisting pulmonary or cardiac disease but may occur (although rarely) as a primary condition when it is produced by fibrosis and thickening of the vessel intima. An increase in resistance of the vessels in the pulmonary vasculature bed occurs secondary to hypoxemia (oxygen deficiency). Chronic hypoxemia produces hypertrophy of the medial muscle layer in the smaller branches of the pulmonary artery, which decreases the size of the vessel lumen. Vasoconstriction, the pulmonary system’s response to hypoxemia, results in a pressure buildup in the right side of the heart because flow through the pulmonary system is impaired. When hypertension in the pulmonary system (measured as pulmonary vascular resistance) is greater than the ability of the right side of the heart to pump, the cardiac output falls and may cause shock.
Causes
The cause of primary pulmonary hypertension is unknown, but the disease tends to occur in families. Secondary pulmonary hypertension is caused by conditions that produce hypoxemia, such as chronic obstructive pulmonary disease, obesity, alveolar hypoventilation, smoke inhalation, and high altitude. Associated diseases include connective-tissue diseases, thyroid disease, liver cirrhosis, stimulant abuse, and HIV infection.
Genetic considerations
Familial primary pulmonary hypertension typically shows an autosomal dominant mode of inheritance and reduced penetrance and is more common in women than in men. Autosomal recessive transmission has also been documented. When pulmonary hypertension is inherited, it demonstrates the genetic concept of anticipation, where subsequent generations often have severe cases of the disease. Pulmonary hypertension is also seen in conjunction with other genetic problems such as hereditary hemorrhagic telangiectasia type 2. Mutations in the BMPR2 gene are associated with both heritable and sporadic forms of the disease, but for many cases, a gene mutation has not yet been identified.
Gender, ethnic/racial, and life span considerations
Pulmonary hypertension is most commonly seen in the elderly person with cardiac or pulmonary disease. It may occur at any age, however. Idiopathic primary pulmonary hypertension tends to occur more often in women between ages 20 to 40. Congenital causes may lead to occurrence in the pediatric population. There are no known racial or ethnic considerations.
Global health considerations
The global incidence rate is approximately 2 to 6 cases per 1 million individuals per year. Pulmonary hypertension exists around the globe at approximately the same incidence as in the United States.
Assessment
History
Patients are usually without symptoms until late in the disease. Up to 50% of the pulmonary circulation may be impaired before significant hypertension is produced. Determine the presence of risk factors. Ask if the patient has experienced chest pain, labored and painful breathing (dyspnea), or syncope. Occasionally, the enlarged pulmonary artery compresses the left recurrent laryngeal nerve, producing hoarseness. Some patients may describe periods of heart palpitations.
Physical examination
Signs of right ventricular failure are common, such as dyspnea, weakness, and recurrent syncope likely accompanied by jugular venous distention, increased central venous pressure, and peripheral edema. Low cardiac output may produce central cyanosis, syncope, or chest pain. Auscultation of the heart may therefore reveal atrial gallop at the lower left sternal border, narrow splitting of S2 or increased S2 intensity, or ejection click at the second intercostal space, left sternal border. When palpating the precordium, you may detect a heave over the right ventricle or an impulse from the pulmonary artery itself. Signs of left ventricular failure, such as systemic hypotension (low blood pressure) and low urinary output, may coexist. Presentation may include hyperventilation, coughing, and eventually rapid breathing (tachypnea) or dyspnea. Initially, breath sounds may be clear or decreased, but you may hear crackles or wheezing.
Psychosocial
The patient is experiencing a potentially life-threatening condition that requires the use of complex medical technology. Assess the anxiety level of the patient and plan interventions to place a minimum demand on the patient’s energy. Support of the patient is essential throughout hospitalization, from routine care such as placement and maintenance of the pulmonary artery catheter to attempts at averting a cardiac arrest.
Diagnostic highlights
| Test | Normal Result | Abnormality With Condition | Explanation |
|---|---|---|---|
| Echocardiogram | Normal lung structures and circulation | Right-to-left shunting across a patent foramen ovale (occurs in approximately 33% of patients with pulmonary hypertension) | Estimate ventricular functioning; pulmonary hypertension may occur because of right to left shunting |
| Pulmonary artery pressure and pulmonary vascular resistance (PVR) (measurements made with a pulmonary artery catheter) | Systolic: 15–20 mm Hg; diastolic: 8–15 mm Hg; PVR: 180–285 dynes/sec per cm–5 per m2 | Pressures elevated, with systolic pressure < 25 mm Hg; pulmonary artery systolic pressure may approach systemic arterial pressure | Sustained elevation of pulmonary vascular pressures |
Other Tests: Antinuclear antibody to exclude autoimmune disorders, thyrotropin, HIV testing, pulmonary function tests, exercise testing, electrocardiogram, ventilation perfusion scan, pulmonary angiogram, chest x-rays, echocardiogram, high-resolution computed tomography
Primary nursing diagnosis
Diagnosis
Impaired gas exchange related to changes in the alveolar membrane structure and increased pulmonary vascular resistanceOutcomes
Respiratory status: Gas exchange; Respiratory status: Ventilation; Comfort level; Anxiety controlInterventions
Airway insertion and stabilization; Airway management; Respiratory monitoring; Oxygen therapy; Mechanical ventilation; Anxiety reductionPlanning and implementation
Collaborative
Primary pulmonary hypertension has limited therapy, and patients tend to have hemodynamic deterioration in spite of therapy. The median survival rate after diagnosis is 2.5 years. Supportive measures include supplemental oxygen for people who are hypoxemic and the use of diuretics in people who are fluid-overloaded. Relief of hypoxemia helps reduce pulmonary vasoconstriction. If the origin of the problem is structural, surgery may be attempted. Heart-lung transplantation is a consideration for severe conditions.
Pharmacologic highlights
| Medication or Drug Class | Dosage | Description | Rationale |
|---|---|---|---|
| Diuretics | Varies by drug | Loop diuretics, thiazide diuretics | Reduce both right and left ventricular failure |
| Sodium warfarin (Coumadin) | 5 mg PO initially, guided by coagulation studies | Anticoagulant | Prevents microvascular thrombosis, venous stasis, and limitation of physical activity |
| Vasodilators | Varies by drug | Nitrates; calcium channel blockers; prostacyclin analogs: epoprostenol (Flolan), treprostinil (Remodulin), iloprost (Ventavis); endothelin antagonists: bosentan (Tracleer), ambrisentan (Letairis) | Improve muscle tone in pulmonary vascular bed and reduce right ventricular workload |
| Sildenafil (Revatio) | 20 mg PO tid | Phosphodiesterase type 5 (PDE5) inhibitor | Promotes selective smooth muscle relaxation |
Other Drugs: Bronchodilators to improve hypoxemia and reduce pulmonary vascular resistance (note that use of vasodilators is limited because it may produce systemic hypotension); oral prostacyclin (PG12) treprostinil extended-release tablets to cause vasodilation.
Independent
If the patient is critically ill, to minimize the risk of infection, use the sterile technique during setup and maintenance of the pulmonary artery catheter. Dressings should be changed according to policy, usually every 72 hours. Ask the patient to evaluate chest pain using a scale from 1 to 10 and provide comfort measures in addition to any ordered medication. Reduce energy demands by assisting the patient to a position of comfort, such as the semi-Fowler’s or Fowler’s position. Document pulmonary artery catheter readings and report significant changes to the medical team. Monitor the patient for the development of cardiac dysrhythmias.
Allow the patient to verbalize fears and assist in the development of a realistic perception as the patient appears ready. Because this is a disease that may affect young women in their 20s and 30s, consider the effects on their lifetime goals. Family considerations, especially if the patient is the mother of young children, requires sensitivity and possible referral. Incorporate family members and other support system members as appropriate. Help the patient adjust to the limitations imposed by this disorder. Advise against overexertion and suggest frequent rest periods between activities. The patient may need diversionary activities during periods of restricted activity. Be sure the patient understands dietary limitations and medication regimens.
Evidence-Based Practice and Health Policy
Sztrymf, B., Souza, R., Bertoletti, L., Jaïs, X., Sitbon, O., Price, L.C., …Humbert, M. (2010). Prognostic factors of acute heart failure in patients with pulmonary arterial hypertension. The European Respiratory Journal, 35(6), 1286–1293.
- Right ventricular failure is a major complication of pulmonary hypertension and is associated with increased mortality.
- Investigators conducted a study among 46 adult patients who were admitted to an intensive care unit (ICU) with acute right ventricular failure secondary to pulmonary hypertension and found that mortality in the ICU was 41.3%. The average time from pulmonary hypertension diagnosis to ICU admission was 6.3 years (range, 2.3 to 16.5 years).
- Nonsurvivors had higher serum brain natriuretic peptide (BNP) levels (median, 1,415 pg/mL versus 628 pg/mL; p = 0.0007), higher serum creatinine levels (112 mol/L versus 95 mol/L; p = 0.04), and higher C-reactive protein levels (40 mg/L versus 12 mg/L; p = 0.01) upon admission. Nonsurvivors were also more likely to develop an infection while hospitalized compared to survivors (73.7% versus 22.2%; p = 0.0005).
Documentation guidelines
- Vital signs, including pulmonary artery catheter readings
- Cardiovascular and pulmonary physical assessment data, including breath and heart sounds as noted in previous sections
- Responses to therapies and disease status, including medication, diet, fluids, oxygen administration, and psychological/family coping
Discharge and home healthcare guidelines
Risk for recurrent pulmonary embolism can be reduced by teaching the patient to minimize hypercoagulability, to reduce venous stasis, and to control risk factors such as obesity. Teach the patient to drink 2,000 mL of fluid a day unless restricted, to rest between activities, and to avoid overexertion. Teach the patient about the prescribed dosage, route, action, and follow-up laboratory work needed for all medications. If the patient is discharged on potassium-wasting diuretics, encourage a diet that is rich in high-potassium foods, such as apricots, bananas, oranges, and raw vegetables. The patient may also need instruction on a low-sodium diet. If the patient needs home oxygen, instruct the patient and significant others in oxygen use and oxygen safety. Arrange with social services for the delivery of oxygen equipment. If the patient smokes, teach strategies for smoking cessation or provide a referral for smoking-cessation programs. Assess the family situation and the effects of a chronic and debilitating disease that will affect occupational goals, child care, role fulfillment, and long-term health.