Biomedical Engineering Reference
In-Depth Information
particular animals intensively. Another option is to house in
protected contact, with a panel containing bars or holes
separating the pair. This form of housing allows recuper-
ating animals and their partners to have limited tactile
contact with each other in adjoining housing space while
minimizing risk of injury (
Baker et al., 2008
). These
alternative housing configurations and other accommoda-
tions, such as enhancing the inanimate environment, should
be utilized if they will help decrease distress associated
with prolonged separation from social partners.
occurs toward one or more individuals, animals that are
being pursued may experience excessive body tempera-
tures when attempting to escape from aggressors. The risk
of hyperthermia increases when the ambient temperature
and humidity are high.
Hyperthermia is classified as “classical” if the animal's
temperature derangement results from elevated external
temperature and “exertional” if it is the result of exercise.
Heat stroke often results from a combination of these
factors (
Serrano, 2007
). The body's physiological response
to elevated temperature is activation of the thermoregula-
tory center in the hypothalamus, which results in increased
blood flow to the surface of the body, increased cardiac
output, and increased ventilation. Water and sodium are
conserved and plasma volume and glomerular filtration
increase. The adaptive response to hyperthermia can be
destructive when heat shock proteins, which increase in
response to increased temperature and function to protect
the cells, create a systemic inflammatory response. This
systemic response is akin to shock and can lead to multiple
organ dysfunction syndrome (MODS) (
Serrano, 2007
). In
a study of pigtail macaques (Macaca nemestrina), elevation
of body temperature to 42
C (108
F) resulted in neuro-
logical derangements that were reversible, although
animals eventually succumbed to shock (
Eshel and Safar,
2002
).
EMERGENCIES AND DISEASES COMMON
TO NONHUMAN PRIMATES REQUIRING
CRITICAL CARE
The focus of this section of the chapter is to provide
information about emergency treatment and provision of
critical care for commonly encountered disease states seen
in nonhuman primates. More detailed information about
the pathophysiology of specific pathogens and diseases
discussed below can be found in other chapters of the topic.
Hyperthermia
Body temperature greater than 42
C (108
F) is associ-
ated with a poor prognosis, and most fatalities occur
within the first 24 hours.
l
Clinical Signs
Clinical signs of heat stroke include elevated core body
temperature accompanied by listlessness, collapse, shock,
ataxia, blindness, disorientation, dehydration, tremors,
seizure, coma, petechiation, ecchymoses, vomiting, and/or
hemorrhagic diarrhea (
Plunkett, 2000
).
Most clinical signs are neurological in origin.
l
Body temperature in conjunction with clinical signs is
diagnostic.
l
Treatment should be aimed at rapidly decreasing body
temperatures via evaporative cooling and intravenous
fluids in conjunction with supportive therapy to address
neurological signs.
l
Diagnostics
It is important that an accurate core body temperature be
taken. While tympanic membrane thermometers are
convenient and easy to use, they tend to register lower
readings than rectal thermometers (
Serrano, 2007
). In
addition, microchip technology is often capable of
providing temperature in addition to an animal's identifi-
cation number, but given the superficial location of
a subcutaneous microchip, readings are more susceptible to
environmental temperature extremes than standard rectal
thermometers. However, this difference may be greater in
outdoor environments. In a study comparing temperature
measurements in marmosets using subcutaneous tran-
sponders and rectal thermometer probes, the variation
between the two methods was not significant (
Cilia et al.,
1998
). In conjunction with history, elevated core body
temperature, and clinical signs, clinical pathology may
indicate hemoconcentration, dehydration, azotemia, and
hypoglycemia. Additional diagnostics
Appropriate management
is
the most
important
l
preventive factor.
Etiology/Risk Factors/Transmission/Species
Hyperthermia occurs when excessive body heat is gener-
ated through metabolism, exertion, or environmental
conditions. It is categorized as “heat stroke” when
accompanied by neurological or other organ dysfunction
(
Serrano, 2007
). Animals that are dehydrated, obese, aged,
have a history of fighting in warm temperatures, reside in
areas of high environmental humidity, or overexert them-
selves are at risk for hyperthermia (
Plunkett, 2000
). In
addition, failure of HVAC systems and electronic room
temperature monitoring/alert systems puts animals at risk
for hyperthermia. For nonhuman primates housed in
outdoor social groups, the risk of hyperthermia increases
when new social groups are created or new animals are
introduced to existing social groups. When aggression
to evaluate on
