Contents
What Are the Specific Causes of Dyspnea?
When Should I Seek a Physician Evaluation
for Dyspnea?
What Will a Physician Do to Evaluate Dyspnea?
What Can I Do to Prevent Dyspnea?Introduction
“Shortness of
breath” or “breathlessness” is a subjective term used widely to describe a
person’s awareness of his or her own difficulty breathing, the unpleasant
sensation of labored breathing, or respiratory
discomfort. Physicians call shortness of breath
“dyspnea” (1). There are many, many causes of dyspnea, and some
are much more serious than others. Dyspnea can be caused by
diseases, infections, and injuries of the lungs, diseases of the heart, upper
respiratory infections, injury, poor physical fitness, inhalation of a foreign
object, anxiety, and metabolic abnormalities. Dyspnea can be acute,
meaning that it comes on relatively suddenly and disappears after treatment, or
it can be chronic, meaning that it persists for a long time--perhaps for the
rest of the patient’s life. Acute dyspnea may be caused by an
illness such as pneumonia or asthma, whereas patients with chronic bronchitis,
emphysema, or “COPD” (chronic obstructive pulmonary disease) tend to have
chronic dyspnea in spite of ongoing treatment. There is also “acute-on-chronic”
dyspnea, in which a patient with chronic lung disease has an acute
deterioration; this often compels the patient to assume a “tripod” position to
minimize the work of breathing (FIGURE 1, (FIGURE 1, reproduced by
permission from UCSD "Catalog of Clinical Images" at
http://meded.ucsd.edu/clinicalimg/index.html with permission of Charlie
Goldberg, MD).
Dyspnea may
occur with or without wheezing (as in asthma), primarily at night or only with
exertion (typical with congestive heart failure), or without warning (as in
pulmonary embolism, the passage of a blood clot from a deep vein in the
body--typically the legs--into the circulation of the
lungs). Dyspnea may indicate life-threatening illness, psychologic
difficulties, poisoning, or merely an ongoing nuisance to the
patient (2).
What Are the Specific Causes of Dyspnea?
The causes
of acute dyspnea--that is, shortness of breath that comes on
over minutes, include:
- pneumothorax, or
collapsed lung (FIGURE 2), which usually results from trauma to the
chest, whether blunt (such as a fall or automobile accident that breaks
ribs) or penetrating (such as a stab wound or a gunshot wound), but can
also occur “spontaneously.” Spontaneous pneumothorax is
actually rather common, and usually results from the rupture of a “bleb,”
or abnormal air-filled sac of lung tissue, most often in younger people
(age 20-40) who are tall and thin. Traumatic pneumothorax and
associated injuries may be fatal, and treatment usually involves inserting
a needle and tube into the chest. Spontaneous pneumothorax may
or may not require specific treatment and is hardly ever
life-threatening;
- pulmonary embolism, or a
blood clot lodged in and blocking one of the arteries supplying blood flow
to the lungs (FIGURE 3). Such clots usually originate
elsewhere in the body, especially in the legs. Sudden onset of
dyspnea in a person with a swollen leg and/or coughing up blood is very
worrisome for pulmonary embolism, which can be
life-threatening. Patients with this combination of symptoms
should go to the closest emergency department;
- bronchospasm, or
wheezing, which is usually due to a flare-up of asthma (3) or to
the inhalation of a noxious gas such as chlorine (bleach) or hydrogen
sulfide. If there are multiple people from one area with acute
dyspnea, poisoning or toxic inhalation may be more likely. As
the word implies, “bronchospasm” is the “spasm” (concentric closing down)
of the bronchial tubes (the small breathing tubes deep in the
lungs). There are medicines that physicians prescribe to block
and reverse the spasm, and it is important that patients receive these
urgently to prevent potentially serious outcomes;
- heart problems,
including heart attack and congestive heart failure. In up to
one-third of patients experiencing a heart attack, chest pain is not a
predominant symptom. In those patients, dyspnea is very common
and may provide the treating physician a clue that the heart muscle is in
jeopardy. Sudden onset of shortness of breath, particularly at
rest, should always prompt a physician evaluation, usually in an emergency
department. Congestive heart failure usually comes on a bit
less acutely, and results from diminished pumping efficiency in the heart
so that body fluids that are ordinarily circulated in the bloodstream
actually back up into the lungs. Fluid in the spaces of the
lungs where oxygen and carbon dioxide are supposed to be exchanged makes
that exchange less efficient and patients will feel short of breath
because of a relative or absolute lack of oxygen. Initial treatment
of congestive heart failure often includes medications that help remove
that fluid from the lungs; and
- anxiety and hyperventilation: a sense of shortness of breath, often accompanied by generalized
concern and hyper-awareness with a sense of panic, is common in patients
with anxiety. Patients who hyperventilate will often feel a
tingling sensation around the mouth and in the fingers and
hands. There may also be lightheadedness and chest
pain. Trying to calm a patient with apparent anxiety may be helpful,
but encouraging the patient to breathe into a paper bag is not
advised (4).
Less acute
causes (that is, onset over hours to days) of dyspnea include all of the above
concerns, pluspneumonia and other lung infections (such as bronchitis),
the dyspnea of which is often but not always accompanied by fever and
cough. Elderly patients may not have clear pneumonia symptoms, but
may be listless and less responsive than usual, in addition to their dyspnea.
Chronic
dyspnea, which patients notice over hours to days, to years, is typically due
to:
- lung disease,
especially chronic bronchitis or emphysema, often called “COPD” by
physicians (5). Such long-term lung disease is usually due
to exposure to toxins, such as tobacco smoke, asbestos, silicone,
etc. Some chronic diseases that affect multiple organs in the
body, such as sarcoidosis, can also cause ongoing dyspnea. The
treatment of chronic dyspnea is usually supportive; if patients’ breathing
difficulty becomes much worse than usual, a physician evaluation should be
sought;
- heart disease, usually
from repeated damage from heart attacks or congestive heart failure;
- anemia, which
may arise from a wide variety of causes, but causes shortness of breath
(particularly with physician exertion) because of diminished
oxygen-carrying capacity of the red blood cells; or
- poor physical condition, usually associated with obesity.
Special
considerations in children under the age of 2 years with dyspnea include
congenital abnormalities of the lungs and heart, croup, and aspiration of a
foreign body into the
lung.
When Should I Seek a Physician Evaluation for Dyspnea?
Generally
speaking, someone experiencing acute onset of dyspnea should be evaluated by a
physician as soon as possible, regardless of the suspected cause. This
ordinarily means going to the nearest emergency department. If the
patient has been prescribed medications or other treatments in the past, it is
usually all right to try those, but doing so should not delay transport to the emergency
department.
Patients
with a history of chronic dyspnea that becomes worse over minutes to hours
should go to the emergency department.
Patients
who have dyspnea with any of the following accompanying problems should also
seek emergency evaluation:
- chest pain
or tightness
- lightheadedness,
passing out, or confusion
- trauma to
the chest
- coughing up
blood
- swelling of one leg or known deep vein thrombosis (DVT) anywhere in
the body
- a history of pulmonary embolism or other abnormal blood clotting in
the past
- asthma symptoms not responding to usual therapy
- a history of spontaneous pneumothorax in the past
- suspected
toxic inhalation or poisoning
- chronic dyspnea that does not improve with usual care
Patients with
dyspnea and any of the following symptoms (and none of those listed above)
should plan to see a physician within the next 24-48 hours, but not necessarily
in an emergency department, unless their symptoms worsen:
- fever
- cough with greenish or yellow phlegm
- chest pain
with coughing
- swelling of
both legs
- new symptoms of dyspnea when lying down to sleep
- chronic dyspnea with activity that now is starting to persist after
rest
What Will a Physician Do to Evaluate Dyspnea?
Physicians
first make certain that a life-saving intervention, such as assisted breathing
or treatment for a heart attack or blood clot in the lung is not
needed. This is done by interviewing and examining the patient, and
inquiring about other medical problems, any accompanying symptoms, and any
prior treatment. In addition to measuring vital signs (temperature,
blood pressure, pulse rate, and breathing rate), the physician will usually
check a “pulse oximetry” reading at the fingertip, which is a painless method
of assessing how well oxygen is being delivered to the tissues of the body.
A chest
radiograph (x-ray) is commonly part of the evaluation, although it may not
reveal the underlying problem. A chest x-ray, for example, will show
congestive heart failure or a pneumothorax, but may be relatively normal in
patients with asthma, pulmonary embolism, and sometimes even in early
pneumonia. Blood tests may be required; usually the blood is obtained by
puncturing a vein, but occasionally physicians need a more thorough analysis of
how well the blood is carrying oxygen, and they will obtain blood from an
artery, usually in the wrist or the inside of the elbow. Although
more painful for the patient, this “arterial blood gas” (ABG) analysis provides
much useful information to the physician treating a patient with dyspnea.
An
electrocardiogram (ECG or EKG) is obtained if there is any suspicion that the
heart is involved in the patient’s dyspnea. More specialized tests,
such as an echocardiogram or a “CAT” scan of the chest are occasionally needed.
What Will a Physician Do to Treat Dyspnea?
- for pneumothorax, treatment may range from simple observation, to
the surgical placement of a tube into the chest to help re-inflate the
collapsed lung
- for pulmonary embolism, medications that thin the blood
- for bronchospasm, medications (some inhaled [called
“bronchodilators”], some given by mouth or intravenously) that relieve the
spasm
- For toxic inhalation, usually removal from the offending substance,
observation, and support are adequate
- For suspected or confirmed heart attack, specific treatments are
provided with medicines and sometimes in the cardiac catheterization laboratory;
for congestive heart failure, diuretics (drugs that help rid the body of
excess fluids) and medications that help the heart beat more efficiently
are given
- For anxiety and hyperventilation, exclusion of more serious causes
of acute dyspnea, and relaxation therapy, psychotherapy, and sometimes
medicines
- For pneumonia, bronchitis, and other infections, antibiotics are
often prescribed; many such infections, however, can also be caused by
viruses, for which antibiotic therapy is not helpful
- For chronic lung and heart problems, there are many, many chronic
treatments that are tailored to the individual patient’s needs
- For anemia, transfusion may be needed acutely; there are also
medicines that can help the body produce more red blood cells over time
- For poor physical condition, there is no acute treatment, but
institution of healthy habits and a safe weight-loss regimen can be very
helpful over time; avoiding tobacco use is essential to good lung and
cardiovascular health
- Dyspnea is a common and troubling symptom at the end of life, and
affects not only patient but also the attending family. Patients in
hospice care often experience significant and uncomfortable dyspnea as
their condition deteriorates. Dyspnea in terminally ill patients,
however, may be treatable; anxiety, fluid in the lungs, or pneumonia may
cause dyspnea that may be at least partially reversible with treatment
that does not violate the hospice approach, including the use of
supplemental oxygen. A physician should be consulted about such
issues; at the end of life, narcotics may be used to keep
the patient comfortable.
What Can I Do to Prevent Dyspnea?
Acute
dyspnea may often be avoided by such simple practices as good hygiene, like
hand washing, avoiding prolonged contact with others who are ill with
contagious diseases, taking medications prescribed for respiratory or cardiac
ailments, and by avoiding inhalation of toxic substances, including tobacco
smoke. Sometimes relief from acute dyspnea can be achieved simply by
moving into an open-air area, or sitting in front of an open
window. Maintaining at least a reasonable level of physical fitness
and avoiding obesity with exercise and a prudent diet will decrease the effort
of breathing all during a person’s lifetime. Chronic dyspnea may
also be avoided by not smoking tobacco, by taking prescribed medications
including the use of prescribed oxygen, and by observing healthy habits.
