with low blood pressure and shock. In such clients, the drug is incompletely absorbed
or its absorption is delayed; therefore, the client may continue to complain of pain, and
an additional dose may be given. When the circulation is improved, an excessive
amount of morphine may suddenly be absorbed.
(1) Symptoms. When coma, depressed respiration, and pinpoint pupils
appear concurrently in a client who has been given morphine, it is likely that he has
morphine poisoning. The client is usually asleep or stuporous; he may be in a profound
coma if the overdose is large. The respiratory rate is very low, sometimes only 2 to 4
per minute, and the client may be cyanotic. The blood pressure is normal at first, then
falls progressively. The pupils are pinpoint in size, unless oxygen depletion is severe; in
that case, they will be dilated. Urine formation is depressed; body temperature falls;
and the skin becomes cold and clammy. The skeletal muscles are lax and soft, the jaw
is relaxed, and the tongue may fall back and block the airway.
(2) Treatment. The prompt restoration of normal respiration is of first
importance, since death in morphine poisoning is nearly always because respiratory
failure. The client's airway must be kept open, and artificial respiration is too slow to
provide adequate oxygenation. Naloxone may be given as directed to treat the
respiratory depression. Cold towels may be used to keep the client awake. If the client
has taken the morphine orally, he may be treated with emetics and gastric lavage. A
careful record of the client's intake and output should be made, because overdosage of
morphine may damage the kidneys and cause suppression of urine. After the danger
has passed, a laxative may be indicated to relieve constipation.
f. Cautions and Contraindications. There are a number of contraindications
to the use of morphine, as follows:
(1) Abdominal pain. A person's life may depend upon the correct diagnosis
of abdominal disease, and pain is an important symptom. Relief of pain causes the
true picture of the symptoms to become blurred. A diagnosis made on this basis may
not be accurate. Therefore, morphine should not be given for any undiagnosed
abdominal condition.
(2) Injuries of the head. Morphine is contraindicated because it distorts the
symptom picture and interferes with diagnosis. Morphine also causes an increase in
intracranial pressure.
(3) Chest injuries or depressed respiration. Morphine should not be given
to anyone with a chest injury, or whose respiratory rate is under 12 per minute. In such
a case, the drug would cause further respiratory depression, and this might be fatal.
(4) Unconsciousness. Morphine is contraindicated when the person is
unconscious.
MD0913
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