Biomedical Engineering Reference
In-Depth Information
TABLE 17.1
Miscellaneous Drug Doses for Use in Nonhuman Primates
Drug
Use
Species
Dose
Duration
Comments
Atropine
Prevent/treat vagally
induced bradycardia,
antisialogogue
Multiple
0.025e0.05 mg/kg
s.c., i.m.
May also be used to correct
opioid-induced bradycardia
Glycopyrrolate
Prevent/treat vagally
induced bradycardia,
antisialogogue
Multiple
0.005e0.01 mg/kg i.m.
Known to be longer
acting than atropine
in other species
May also be used to correct
opioid-induced bradycardia
Does not cross the
bloodebrain barrier
Less side effects than
atropine in other species
Metoclopromide
Antiemetic
Multiple
0.2 mg/kg s.c., i.m.
Rapid intravenous
administration can be
proemetic
Ranitidine
Gastroprotectant
Multiple
1 mg/kg p.o., i.m., i.v.
8e12 h
May be useful during long-
term NSAID therapy
Omeprazole
Gastroprotectant
Macaque
0.4 mg/kg p.o.
12 h
Sucralfate
Gastroprotectant
Multiple
0.5 mg/kg p.o.
12 h
Doses are based on the authors' experience and published data (
Popilskis et al., 2008, Valverde 2005
), and are provided as a general guide only.
p.o., per os; s.c., subcutaneous; i.m., intramuscular; i.v., intravenous.
SELECTING AN ANESTHETIC REGIME
Immobilization/Deep Sedation/Light
Anesthesia
A very wide range of agents can potentially be used for
anesthetizing nonhuman primates. Anesthesia can be
produced by injectable agents (e.g. propofol), by inhalation
agents (e.g. isoflurane), or local anesthetic agents (e.g.
lidocaine). Most often a combination of these techniques
are used to produce what
allows the animal to be confined for injection or the animal
is trained to co-operate and accept the injection without the
need for physical restraint (see section “Is anesthesia
necessary?” above). Ketamine produces immobility and
analgesia and is the most widely used agent for initial
restraint of larger primates. Even at light levels of sedation,
the bite reflex is often lost but swallowing and laryngeal
(cough) reflexes are retained. This can be an advantage in
that even after withholding of food, some animals may have
ingested bedding or other material while in their cage, and
may still vomit or regurgitate when sedated; the mainte-
nance of potentially protective reflexes reduces (but does
not eliminate) the possibility of aspiration. Because
the laryngeal reflex is retained if ketamine is used as
a sole agent for immobilization another agent should be
administered before endotracheal intubation (see section
“Endotracheal Intubation” below) is performed. Ketamine
is usually administered intramuscularly, but it can also be
given orally (
Pulley et al., 2004
) if i.m. injection is not
possible. Oral administration is most effective if ketamine
is applied to the mucous membranes of the mouth; once in
the stomach it undergoes some first-pass liver metabolism.
Both onset of action and the peak effect are markedly
reduced compared to administration by injection and 4
e
10
times the intramuscular dose is required. However, oral
ketamine is still useful to sedate animals that have escaped
from cages, e.g. if injected into foods such as bananas.
Repeated ketamine or tiletamine administration may be
undesirable because of concern about the neurotoxic effects
of NMDA antagonists that have been demonstrated in
is referred to as “balanced
anesthesia.”
The choice of a particular technique will depend on
a variety of factors
e
for example the species of animal, the
depth and duration of anesthesia required, availability of
equipment such as anesthetic machines, and the experience
and skills of the operator.
As previously mentioned, the use of anesthetic drugs for
immobilization of nonhuman primates, before the induc-
tion of a surgical plane of anesthesia, is often essential
because of concerns for the safety of the staff involved.
However, the same drugs used for this purpose lead to
a light plane of anesthesia that, in combination with anal-
gesic agents, can be suitable for minor surgical procedures.
For a guide to drug doses see
Table 17.2
.
Ketamine
In most instances a dissociative anesthetic, for example
ketamine or tiletamine, is administered i.m. to immobilize
the animal. This is facilitated by use of a cage design that
