(5) Inhaled allergens. If the person is allergic to such substances as animal
hair, dust, ragweed or pollens, these can cause anaphylactic shock.
b. People with a history of allergies are more likely to develop anaphylactic
problems than those who do not have such a history. The patient should be questioned
carefully and any known allergies should be posted on the patient's chart in a manner
that is easily visible to anyone who is concerned with patient care. When a serum such
as horse, rabbit, or bovine is being considered for injection, the person should be tested
for sensitivity. A small amount is inserted just under the skin on the forearm. After a
few minutes, the site may produce itching, a red appearance, or a slight rash. These
results indicate a positive reaction and the physician must be notified before the
considered serum is used.
SIGNS AND SYMPTOMS
The signs and symptoms of anaphylactic shock occur almost instantaneously.
Sometimes they will happen within minutes or even seconds. Less frequently they take
an hour or more to develop. In many cases, the only immediate reaction is loss of
consciousness. In other cases, there will be early feelings of uneasiness or
apprehension, general weakness, perspiration, sneezing, or nasal pruritis.
a. Respiratory Signs. Sneezing and coughing caused by spasms in the
bronchioles may be the first signs. Wheezing will be audible and there is a painful
tightness or squeezing sensation in the chest. There will be difficulty in breathing and
possible edema of the larynx and/or epiglottis. Cyanosis may also be evident.
b. Involvement of the Skin. There may be itching and a sensation of warmth
especially near the face and on the chest. This is usually accompanied by a reddening
of the skin. If the itching is generalized, a general systemic reaction is beginning.
Patches of urticaria (hives) may also appear. The skin may appear pale as the
peripheral blood vessels collapse. If massive angioedema occurs on the face, this is
caused by the swelling of the blood vessels just underneath the skin. This may indicate
upper respiratory edema.
c. Cardiac and Circulatory Involvement. The pulse may be rapid or weak or it
may not be possible to get a pulse. There is a falling or very low blood pressure.
Tachycardia or bradycardia may be apparent. There could be a diminished stroke
volume and consequently diminished cardiac output. In fatal cases, a complete
circulatory failure leads to a coma and death.
d. Gastrointestinal Effects. Nausea and vomiting are common problems.
There may be colicky abdominal pains or convulsions. Diarrhea and fecal and/or
urinary incontinence may occur.