Definition
A.Dyspnea occurs when a patient experiences any level of breathing discomfort. The symptom is often associated with pulmonary disorders and cardiac ischemia and is a significant predictor of mortality. The risk of experiencing dyspnea increases with age. Up to 37% of people older than the age of 70 experience dyspnea. Treatment is directed at identifying and managing the underlying pathologic concern.
Incidence
A.Dyspnea affects up to one half of patients seen in hospitals and up to one fourth of patients seeking outpatient care.
B.Millions of patients living at home experience chronic dyspnea related to pulmonary and cardiac morbidities.
C.Between three and four million emergency room visits annually are due to some level of dyspnea.
D.Dyspnea is associated with cardiovascular disease (leading cause of death in the United States) and pulmonary disease (asthma and chronic obstructive pulmonary disease (COPD), affecting more than 25 million).
Pathogenesis
A.Respiration is controlled by peripheral chemoreceptors in the carotid bodies and aortic arch, and central chemoreceptors in the medulla.
B.Chemoreceptors are stimulated by a drop in partial pressure of oxygen in arterial blood, a drop in pH, and a change in pCO2 levels.
C.Additional receptors play a role in maintaining oxygenation including mechanoreceptors in the upper airway, pulmonary receptors, and chest wall receptors.
D.Breathing discomfort occurs when a patient recognizes hypoxia and hypercapnia. Dyspnea is experienced because of physical, psychologic, social, and environmental factors.
E.For adequate gas exchange to occur, oxygen must reach the alveoli from the environment. If any part of the airway is compromised, including the alveolar beds, the process is dysfunctional to some degree.
F.In addition to intact respiratory receptors and a clear airway for gas exchange, the act of breathing also requires muscular strength and adequate hemoglobin levels to transport oxygen.
Predisposing Factors
A.Asthma.
B.COPD.
C.Interstitial lung disease.
D.Cardiovascular disease.
E.Deconditioning/obesity.
F.Severe anemia.
G.Foreign body.
Common Complaints
A.Difficulty breathing or the sensation of air hunger.
B.Change in respiratory pattern.
C.Potential wheezing.
D.Weakness.
E.Fatigue.
F.Functional disability.
Other Signs and Symptoms
A.Chest tightness.
B.Rapid or shallow breathing.
C.Breathing feels heavy.
D.Chronic dyspnea is associated with depression.
E.Severe, acute dyspnea is associated with a sensation of impending death.
F.Headache.
G.Anorexia.
Potential Complications
A.Hypoxemia.
B.pH imbalance.
C.Cardiac dysrhythmias.
D.Confusion.
Subjective Data
A.Determine the onset, duration, and course of dyspnea.
B.Determine if any short-acting beta-2 agonists (SABA; rescue) inhaler was used, the name, quantity used, effectiveness, and when last used.
C.Establish medical history, including pulmonary, cardiac, neuromuscular, or hematologic impairments.
D.Determine smoking history, including inhalation of illicit substances (methamphetamines).
E.Rate the degree of dyspnea on a dyspnea scale.
F.Ask patient to list all medications currently being taken, including oral or aerosolized herbal products.
G.Ask about exposures to caustic substances, including fumes, smoke, carbon monoxide in the home or workplace, and occupational exposures to inhaled toxins.
H.Is there associated cough or wheezing?
I.Pain in chest wall, mental confusion, or extreme fatigue.
J.Determine if there is a history of anxiety or panic episodes.
K.Ask about use of emergency services or need for hospitalization due to dyspnea.
L.Consider if the patient has established advance directives and made any change from previous directives.
Physical Examination
A.Check temperature (if indicated), blood pressure (BP) pulse, pulse oximetry, level of consciousness (LOC), and ability to speak in complete sentences without obvious air hunger.
B.Inspect:
1.Inspect general appearance, noting degree of dyspnea, respiratory pattern.
2.Check trachea for deviations.
3.Inspect for use of accessory muscles of breathing.
4.Inspect skin for pallor, cyanosis, bruising, open wounds, petechiae, and turgor.
5.Inspect facial features for fear, lethargy, or angioedema.
6.Inspect legs for edema.
7.Capillary refill.
C.Palpate:
1.Palpate chest wall for tenderness/injury.
2.Palpate radial and peripheral pulses for amplitude and rhythm.
3.Palpate chest wall for crepitus.
D.Auscultate:
1.Cardiac for rhythm, S3/S4.
2.Lungs in all fields for adventitious sounds.
3.Abdomen for distension.
Diagnostic Tests
A.ECG: Shows inverted T waves, ST segment elevation, and Q waves. One normal ECG initially does not always rule out myocardial infarction (MI); perform serial ECGs if MI suspected.
B.Arterial blood gas (ABG).
C.Chest x-ray.
D.Complete blood count (CBC) with differential.
E.Comprehensive metabolic panel (glucose, electrolytes, renal and hepatic functions).
F.Brain natriuretic peptide (BNP).
G.Thyroid-stimulating hormone (TSH).
H.Pulmonary function tests (PFTs).
Differential Diagnosis
A.Acute MI.
B.Pulmonary embolus.
C.Aortic dissection.
D.Pneumothorax.
E.Poisoning (secondary to inhaled elicit substances or unintentional: carbon monoxide).
F.Asthma, uncontrolled.
G.COPD exacerbation.
H.Pulmonary fibrosis.
I.Pulmonary edema.
J.Neuromuscular dysfunction.
K.Respiratory suppression secondary to medication overdose.
L.Anemia.
M.Anxiety/panic episode.
N.Developing pregnancy with gravid uterus.
O.End-stage heart failure.
P.Pulmonary hypertension.
Q.Lung cancer.
R.Progression of morbid obesity and deconditioning.
S.Aspiration or foreign body.
T.Allergic response/angioedema.
Plan
A.Patient teaching:
1.Educate patient about modifying controllable risk factors for pulmonary and cardiovascular disease. Smoking cessation should be addressed at each patient encounter.
2.Discuss the benefits of cardiovascular exercise.
3.The treatment of dyspnea is determined by the underlying etiology.
4.If coronary heart disease (CHD) is present:
a.Make sure patient is aware of signs and symptoms of MI.
b.Make sure patient knows to seek medical attention or dial 911 if signs and symptoms occur.
c.Encourage cardiopulmonary resuscitation (CPR) training for family and/or close friends.
d.Patient should carry fast-acting nitroglycerin at all times and know how to use it.
B.Dietary management: If applicable, counsel patient on benefits of weight loss to comfort of breathing. Encourage well-balanced meals and adequate fluid intake.
C.Pharmaceutical therapy:
1.Oxygen should be delivered based on patient status. For conscious patients in outpatient settings, oxygen is most effectively delivered through a nonrebreather mask. The hypoxic drive is not a consideration for limiting oxygenation in acute emergencies.
2.When MI is suspected: Aspirin 160 to 325 mg (four 81 mg baby aspirin) chewed or swallowed as soon as possible. Enteric-coated aspirin delays absorption and therefore is not recommended.
3.For bronchodilation a SABA should be delivered by inhaler or nebulization.
4.Further intervention must be under the direction of a specialist after a full evaluation.
Follow-Up
A.Follow-up is determined by the patient’s condition and primary diagnosis. Timely follow-up is essential and is based on individual patient considerations. In elderly who live alone, next-day follow-up should be considered if the patient will not be hospitalized.
Emergent Issues/Instructions
A.If you suspect MI as the cause of dyspnea, refer patient through emergency medical service (EMS) for immediate ED evaluation.
B.For suspected pulmonary emboli or dissecting aneurysms, patients should be transported by EMS.
Consultation/Referral
A.Consultation for chronic dyspnea with a pulmonologist if lung disorder.
B.Consultation with appropriate specialist if cardiac, neuromuscular, or hematologic disorder.
C.Referral to pulmonary and/or cardiac rehabilitation services.
D.Referral to occupational therapy for functional rehabilitation
Individual Considerations
A.Pregnancy:
1.For optimal oxygenation, patients with a gravid uterus should be placed on their left side while they are receiving supplemental oxygen.
2.Obstetric referral is recommended for significant dyspnea during pregnancy.
3.Control of asthma or any chronic lung disorder is crucial as the mother must maintain adequate oxygenation to sustain the fetus.
B.Geriatrics:
1.Frailty is a risk marker for morbidity and mortality for all causes of dyspnea.
2.Adult vaccination guidelines (CDC) should be followed for prevention; these are available at www.cdc.gov/vaccines/schedules/downloads/adult/adult-combined-schedule.pdf.
3.The primary care provider should be aware of the patient’s choices in worsening dyspnea. Advance directives should be available on the outpatient medical record.
4.Consideration for hospice or palliative care services should be recommended to support the patient and family early in the course of progressive dyspnea and chronic illness.