484
P A R T 5
Drugs acting on the autonomic nervous system
■■
Beta
1
-selective adrenergic blocking agents do not
block the beta
2
-receptors that are responsible for
bronchodilation and therefore are preferred in
individuals with respiratory problems.
■■
Beta
1
-selective adrenergic blocking agents are used
to treat hypertension and angina in extended-release
forms and to treat HF.
■■
All of the adrenergic blocking drugs must be tapered
when they are discontinued after long-term use.
The blocking of the receptor sites makes them
hypersensitive to catecholamines, and extreme
hypertension, angina, MI or stroke could occur.
KEY POINTS
Care considerations for people receiving
beta
1
-selective adrenergic blocking agents
Assessment: History and examination
■
■
Assess for contraindications or cautions: known
allergies to any drug or any components of
the drug
to avoid hypersensitivity reactions
;
bradycardia or heart blocks, shock or HF,
which
could be exacerbated by the cardiac-suppressing
effects of these drugs
; diabetes, thyroid disease
or COPD
to reduce risk of adverse effects on
these conditions due to sympathetic blockade
;
and current status of pregnancy or breastfeeding
because of the potential effects on the fetus or
neonate.
■
■
Perform a physical assessment to establish baseline
status before beginning therapy
to determine
the effectiveness of therapy and evaluate for any
potential adverse effects.
■
■
Assess neurological status, including level of
orientation and sensation,
to evaluate for CNS
effects.
■
■
Monitor cardiac status, including pulse, blood
pressure, and heart rate,
to identify changes
, and
obtain an ECG as ordered
to evaluate for changes
in heart rate or rhythm
.
■
■
Assess pulmonary status, including respirations,
and auscultate lungs for adventitious sounds
to
monitor respiratory status.
■
■
Examine the abdomen and auscultate bowel
sounds
to evaluate GI effects.
■
■
Monitor urine output
to monitor the effectiveness
of cardiac output and any changes in renal
perfusion.
■
■
Monitor the results of laboratory tests,
including electrolyte levels,
to monitor for risk
of arrhythmias
, and renal and hepatic function
studies,
to determine the need for possible dose
adjustment.
Implementation with rationale
■
■
Do not stop these drugs abruptly after chronic
therapy, but taper gradually over 2 weeks
to
prevent the possibility of severe reactions.
Long-term use of these drugs can sensitise the
myocardium to catecholamines
and severe
reactions could occur.
■
■
Consult with the doctor about discontinuing these
drugs before surgery
because withdrawal of the
drug before surgery when the person has been
maintained on the drug is controversial.
■
■
Give oral forms of metoprolol with food
to
facilitate absorption.
■
■
Continuously monitor any individual receiving an
intravenous form of these drugs
to detect severe
reactions to sympathetic blockade and to ensure
rapid response if these reactions occur.
■
■
Arrange for supportive care and comfort measures,
including rest, environmental control and other
measures,
to relieve CNS effects
; safety measures
if CNS effects occur,
to protect the person from
injury
; small, frequent meals and mouth care
to
relieve the discomfort of GI effects
; and an activity
program and daily energy management ideas
to
help to deal with activity intolerance.
■
■
Offer support and encouragement
to help the
person deal with the drug regimen.
■
■
Provide thorough teaching, including drug name,
dosage and schedule for administration; use of
drug with food or meals if appropriate; technique
for ophthalmic administration if indicated;
potential adverse effects, measures to avoid drug-
related problems, and warning signs of problems;
safety measures such as changing position slowly
and avoiding driving or operating hazardous
machinery; and energy conservation measures as
appropriate.
Evaluation
■
■
Monitor response to the drug (lowered blood
pressure, fewer anginal episodes, lowered
intraocular pressure).
■
■
Monitor for adverse effects (GI upset, CNS
changes, cardiovascular effects, loss of libido and
impotence, potential respiratory effects).
■
■
Evaluate the effectiveness of the teaching plan
(person can name drug, dosage, adverse effects to
watch for and specific measures to avoid them).
■
■
Monitor the effectiveness of comfort measures and
compliance with the regimen.
