C H A P T E R 4 5
Antiarrhythmic agents
709
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Ensure that emergency life support equipment is
readily available
to treat severe adverse reactions
that might occur.
■
■
Administer parenteral forms as ordered only if
the oral form is not feasible; expect to switch
to the oral form as soon as possible
to decrease the
potential for severe adverse effects.
■
■
Consult with the prescriber to reduce the dose
in people with renal or hepatic dysfunction;
reduced dose may be needed
to ensure
therapeutic effects without increased risk of
toxic effects.
■
■
Establish safety precautions, including side rails,
lighting and noise control, if CNS effects occur
to ensure the person’s safety.
■
■
Arrange for periodic monitoring of cardiac rhythm
when the person is receiving long-term therapy
to evaluate effects on cardiac status.
■
■
Provide comfort measures
to help the person
tolerate drug effects.
These include small, frequent
meals to minimise nausea and vomiting; access
to bathroom facilities; bowel program as needed
to deal with nausea, vomiting and constipation
;
administration of food with drug if GI upset is
severe
to alleviate the discomfort
; environmental
controls, such as temperature regulation,
light control and decreased noise,
to alleviate
overstimulation if CNS effects occur
; and
reorientation as needed.
■
■
Offer support and encouragement
to help the
person to deal with the diagnosis and the drug
regimen.
■
■
Provide thorough teaching, including the name
of the drug, dosage prescribed, measures to avoid
adverse effects, warning signs of problems and
the need for periodic monitoring and evaluation,
to enhance knowledge about drug therapy and to
promote compliance.
Evaluation
■
■
Monitor response to the drug (stabilisation of
cardiac rhythm and output).
■
■
Monitor for adverse effects (sedation, hypotension,
cardiac arrhythmias, respiratory depression, CNS
effects).
■
■
Evaluate the effectiveness of the teaching plan
(person can name drug, dosage, adverse effects to
watch for, specific measures to avoid them and the
importance of continued follow-up).
■
■
Monitor the effectiveness of comfort measures and
compliance with the regimen.
See the Critical thinking scenario for information
on managing the person on chronic antiarrhythmic
therapy.
CRITICAL THINKING SCENARIO
Managing people on chronic antiarrhythmic therapy
THE SITUATION
R.A., a 63-year-old man, developed atrial fibrillation 2 years
ago, with a rapid drop in blood pressure and a rapid
pulse of 160 beats/minute, irregularly irregular. He was
cardioverted within a few hours of onset to normal sinus
rhythm with a heart rate of 74 beats/minute. He was started
on digoxin (
Lanoxin
) and remained stable for more than
a year. It was decided to stop the drug and monitor R.A.
He did well, but on a long-awaited trip to Italy, he again
developed atrial fibrillation, with rapid pulse and drop
in blood pressure. He was treated at an Italian clinic with
cardioversion and seen by his cardiologist on his return
to Australia. He was again placed on digoxin to maintain
his conversion to sinus rhythm. He called the clinic with
complaints of palpitations and a severe headache and was
told to immediately come in to be evaluated. He was found
to be in sinus rhythm with PVCs. He stated that he felt that
the headache was related to a cold he had been fighting,
and he has been self-medicating with antihistamines.
CRITICAL THINKING
Based on your knowledge of the drug digoxin and
the symptoms reported by R.A, what do you think
happened?
What actions should be taken at this time to make sure that
R.A.’s heart rhythm remains stable?
What teaching points will be essential to convey to R.A.
before he goes home?
What other screening should be done at this time to
prevent problems in the future?
DISCUSSION
R.A. has the signs and symptoms of increased digoxin
levels—headache and ventricular arrhythmias. Initially, R.A.
should be placed on a cardiac monitor and supported to
ensure that the ventricular arrhythmias do not progress. His
digoxin should be stopped until the situation is stabilised.
Emergency life support equipment should be readily
available in case the situation deteriorates.
