Biomedical Engineering Reference
In-Depth Information
Primate Research Center (CaNPRC), 2009) and for amio-
darone is 5.0 mg/kg i.v. or i.o. Amiodarone formulas
available for veterinary medicine are in a carrier that can
cause persistent hypotension so care must be given to dilute
the drug as directed in the package insert and to administer
it slowly over 10 minutes (
Wells, 2008
).
Post-resuscitation monitoring is essential for the
recognition of recurrence of CPA and diagnosis of long-
term complications. Monitoring should include ECG, blood
pressure, pulse oximetry, urine output, pulse character,
mucous membrane color and capillary refill time, PCV, and
neurological status. Supportive treatment should continue
as long as necessary and may include continuing oxygen
therapy, treatment of arrhythmias, prevention of seizures,
administration of intravenous fluids, and inotropic or
pressor therapy to maintain blood pressure.
In the laboratory setting, it may be necessary to anes-
thetize sick or injured nonhuman primates for several
consecutive days in order to change bandages or provide
intravenous fluids. Because it has been shown that repeated
anesthetic events decrease food intake in nonhuman
primates, nutritional support should be considered for
animals that must be anesthetized repeatedly (
Springer and
Baker, 2007, 2008
). It is the authors' experience that
animals with traumatic injury and those that have been
removed from a breeding colony setting to be treated,
especially if it is the first time they have been individually
housed, are especially susceptible to inappetance following
presentation. In addition, animals with dental disease or
soft tissue trauma to the mouth may require softening of the
normal diet so that they are able to ingest sufficient calories
with minimal pain.
In recent years there has been an increase in the
frequency with which both enteral and parenteral nutrition
are utilized for critically ill animals in veterinary practice.
While these methods for providing nutrition may be
appropriate in select cases in nonhuman primate cases, they
require intensive care and monitoring. It is important to
weigh the nutritional benefits against the risks associated
with each method of supplementation. In many cases of
temporary inappetance associated with injury or illness, it
may be sufficient to provide supplementation in the form of
orogastric or nasogastric intubation while the animal is
anesthetized for bandage changes or intravenous fluid
therapy. Warmed, over the counter nutritional supplement
drinks may be suitable in these situations.
While orogastric and nasogastric intubation are useful
for providing short-term nutritional support, a percutaneous
endoscopic gastrostomy (PEG) catheter should be consid-
ered whenever long-term nutritional support is indicated in
nonhuman primates. A PEG tube has a large enough inner
diameter to allow moistened nonhuman primate biscuit
gruel to be administered directly into the stomach. PEG
tubes have been used successfully to provide nutrition in
cases of fatal fasting syndrome in macaques (
Christe and
Valverde, 1999
), as well as a variety of other critical
conditions in nonhuman primates. A benefit of this route of
administration is the ability to maintain more physiological
gastrointestinal motility because the consistency of the diet
is similar to what is normally consumed. An additional
benefit of using the normal diet is that it is calorically dense
and balanced which minimizes any supplementation to
meet dietary requirements. Water can be added to the diet
or administered through the tube as needed to assist in
maintaining hydration. There may be less risk of aspiration
pneumonia with a PEG tube compared to orogastric or
nasogastric tubes since the gruel is more viscous than
a liquid dietary supplement. Additionally, the diet is
administered directly into the stomach without the need to
pass a tube through the oropharynx.
Nutrition
In the critical care of nonhuman primates, the type and
quantity of nutrition that is received by the patient is as
integral to recovery as the medications that are being given.
While adequate nutrition alone cannot cure all diseases, it
can modulate their course. The negative effects of poor
nutrition during critical illness include delayed wound
healing, compromised immune function, decreased
strength, and poorer overall prognosis (
Chan, 2009
).
Diarrhea and large draining wounds, which are two of the
most common causes of morbidity in large breeding colony
settings, are major risk factors for malnutrition due to the
large protein losses associated with these conditions (
Chan,
2009
). Conversely, conditions such as hepatic or renal
failure result in decreased protein requirements, so it is
important to be mindful of the disease state when consid-
ering nutritional supplementation.
Because illness causes the body to shift to a catabolic
state, the goals in providing nutrition to a critically ill
animal should be to mitigate the loss of lean body mass, to
address nutritional deficiencies that may have already
occurred prior to presentation, and to supplement nutrients
that are needed in order for the body to heal (
Chan, 2009
).
While it is common practice to serially weigh ill animals in
order to assess changes in their nutritional state, using an
animal's body condition score (BCS) in conjunction with
laboratory and clinical data may be more useful because
BCS is less affected by alterations in hydration status than
body weight (
Clingerman and Summers, 2005
). A simple
body condition score with a range of values between 1 and
5 has been widely utilized for nonhuman primates. A value
of 3 is indicative of an animal with normal body condition
while a score of 1 indicates cachexia and 5 indicates
obesity. The narrow range of this scale helps to assure that
body condition scoring is reliable and remains consistent
between independent observers.
