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P A R T 8
Drugs acting on the cardiovascular system
directly onto any active bleeding site. These are not yet
available in Australia and New Zealand.
Thrombin, which is derived from bovine sources, is
a solution that is applied topically and mixed in with the
blood. Thrombin recombinant is also a solution and is
applied directly to the bleeding site surface in conjunc
tion with absorbable gelatin sponge; the amount needed
varies with the area of tissue to be treated.
Contraindications and cautions
Systemic haemostatic agents
Aminocaproic acid is contraindicated in the presence
of allergy to the drug
to prevent hypersensitivity reac-
tions
and with acute DIC
because of the risk of tissue
necrosis.
Caution should be used in cardiac disease
because of the risk of arrhythmias
and in renal and
hepatic dysfunction,
which could alter the excretion of
this drug and the normal clotting processes.
Although
the safety for use of this drug during pregnancy has not
been established, it should be used only if the benefits
to the mother clearly outweigh the potential risks to the
neonate
because of the potential for adverse effects on
the fetus.
It is recommended that nursing mothers use a
different method for feeding the baby if this drug is used
because of the potential for adverse effects on the baby.
Topical haemostatic agents
Use thrombin with caution for those people with an
allergy to bovine products.
Because thrombin comes
from animal sources, it may precipitate an allergic
response; the person needs to be carefully monitored
for such a reaction
. Many of the potential allergic reac
tions associated with bovine thrombin will be decreased
as a result of approval for thrombin recombinant to be
made using recombinant DNA technology. Safety for
use of thrombin recombinant in children has not been
established.
Adverse effects
Systemic haemostatic agents
The most common adverse effect associated with
systemic haemostatic agents is excessive clotting. In
2007, there were many reports of increased cardiovas
cular events, including fatalities in people who received
aprotinin. Some of the events occurred months after the
drug was used. The drug was removed from the market
in 2008. CNS effects of aminocaproic acid can include
hallucinations, drowsiness, dizziness, headache and psy
chotic states, all of which could be related to changes
in cerebral blood flow associated with changes in clot
dissolution. GI effects, including nausea, cramps and
diarrhoea, may be related to excessive clotting in the GI
tract, causing reflex GI stimulation. Weakness, fatigue,
malaise and muscle pain can occur as small clots build
up in muscles. Intrarenal obstruction and renal dysfunc
tion have also been reported.
Topical haemostatic agents
Use of absorbable gelatin and microfibrillar collagen can
pose a risk of infection
because bacteria can become
trapped in the vascular area when the sponge is applied.
Immediate removal of the sponge and cleaning of the
area can help to decrease this risk.
Clinically important drug–drug interactions
Systemic haemostatic agents
Aminocaproic acid is associated with the develop
ment of hypercoagulation states if it is combined with
oral contraceptives or oestrogens. The risk of bleeding
increases if it is given with heparin.
Topical haemostatic agents
There are no reported drug–drug interactions with the
topically applied haemostatic agents.
Care considerations for
people receiving systemic haemostatic
Care considerations for a person receiving topical
haemostatic agents are similar to those with the use
of any topical drug (see Appendix C).
Assessment: History and examination
■
■
Assess for the following conditions,
which
could be cautions or contraindications to the
use of systemic haemostatic agents
: any known
allergies to any component of the drug
to prevent
hypersensitivity reactions
; acute DIC
because
of the risk of tissue necrosis
; renal and hepatic
dysfunction,
which could alter the excretion of
these drugs and the normal clotting processes
; and
breastfeeding
because of the potential for adverse
effects on the neonate.
■
■
Assess baseline status before beginning therapy
to
determine any potential adverse effects.
Assess the
following: body temperature; skin colour, lesions
and temperature; affect, orientation and reflexes;
pulse, blood pressure and perfusion; respirations
and adventitious sounds; bowel sounds and normal
output; urinalysis and clotting studies; and renal
and hepatic function tests.
Implementation with rationale
■
■
Monitor clinical response and clotting factor levels
regularly
to arrange to adjust dose as needed.
■
■
Monitor the person for any sign of thrombosis
to arrange to use comfort and support measures
