Encyclopedia of Health and Medicine

H–I
hemoptysis Bleeding from the LUNGS, which typically
manifests through BLOOD in the SPUTUM.
Hemoptysis is typically frothy and bright red,
though can sometimes be difficult to distinguish
from blood that might originate in the ESOPHAGUS
or STOMACH.
Hemoptysis that produces a volume of
blood greater than the equivalent of
two or three teaspoonfuls is a medical
emergency that may represent hemorrhage
and requires immediate treatment.
Hemoptysis is a symptom of numerous health
conditions affecting the lungs, and may appear as
blood-streaked sputum or primarily blood with little
apparent sputum present. The diagnostic path
includes chest X-rays, blood tests, and sputum cultures.
Lung hemorrhage is a surgical emergency
that generally requires immediate intervention to
locate and stop the source of bleeding, commonly
a perforated ARTERY. Treatment for less severe
bleeding focuses on the underlying cause. The
most common cause overall of hemoptysis is
BRONCHITIS.
COMMON CAUSES OF HEMOPTYSIS
BRONCHIECTASIS
CYSTIC FIBROSIS
PNEUMONIA
TUBERCULOSIS
Wegener’s granulomatosis
BRONCHITIS
LUNG CANCER
PULMONARY EMBOLISM
violent coughing
See also ANEMIA; GASTROINTESTINAL BLEEDING.
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hiccups Dysfunctional or out-of-sequence contractions
(spasms) of the DIAPHRAGM. Hiccups generally
occur rhythmically in episodes that typically
contain four to several dozen contractions. An
individual tends to have a personally consistent
pattern. Though doctors know the mechanics of
hiccups, no one knows what causes hiccups or
what, if any, purpose they serve. For most people
hiccups are nothing more than an annoyance.
However, prolonged attacks can have health consequences.
There is no certain cure for hiccups, though
recommended remedies are abundant. Some
remedies, such as swallowing a spoonful of sugar
or sniffing an ammonia capsule, irritate the airways.
Swallowing ice water may activate nerves in
the ESOPHAGUS that diffuse the NERVE impulses
causing the diaphragm to contract. BREATHING into
a paper bag raises the percentage of carbon dioxide
in the BLOOD, which alters the brain signals to
the diaphragm. It is important that any prospective
cure carry little risk of causing harm.
Doctors may treat persistent hiccups with medications
that are mildly sedating, such as antiseizure
or anticholinergic medications. A mild
anesthetic may slow the signals from the brainstem.
Mild MUSCLE relaxants and tricyclic antidepressants
are also successful in some people.
Extended hiccups may result in vasovagal nerve
irritation that causes ARRHYTHMIA (irregularities in
the heartbeat). In most circumstances of prolonged
hiccups, treating underlying health conditions
stops the hiccups.
See also HYPERVENTILATION; MYOCLONUS; SPASM.
hyperventilation Rapid, shallow BREATHING that
causes carbon dioxide levels in the BLOOD to drop
below normal. As the balance between carbon
dioxide and other gases in the blood is essential
for normal pulmonary and cardiovascular func-