Biomedical Engineering Reference
In-Depth Information
A thorough evaluation of the patient's mentation is
important and can provide the practitioner with valuable
diagnostic information. A variety of conditions that can
affect mentation include, but are not limited to, hypogly-
cemia, hypernatremia, hepatic disease, hemorrhage, shock,
and hypoxia. Mental status may be difficult to assess in the
research setting depending on housing type. This is espe-
cially true if a critical patient presents from an outdoor
environment where the animal has been anesthetized for
capture prior to its presentation to the clinic. This issue
underscores the importance of communication with staff,
adequate training in animal observation, and accurate
history collection. Animal care staff who are experienced in
these areas are a critical link in the communication of
important information regarding an animal's condition to
the veterinarian.
Following initial stabilization of the respiratory,
cardiovascular, and nervous systems, problems are priori-
tized and a secondary survey is performed that includes
a thorough history and physical examination (
Kirby, 2009
).
In an outdoor breeding colony setting, the details of an
individual animal's longitudinal disease progression may
not be detailed or as complete as animals housed indoors in
controlled environments. For this reason, it is important for
the clinician to be knowledgeable regarding common cau-
ses of critical illness in nonhuman primates housed under
different conditions and in a variety of environments.
Commonly encountered emergency conditions also vary by
species. Some of the more common examples of emer-
gency conditions that occur in nonhuman primate species
in different environments are covered in the section below,
“Emergencies and diseases common to NHP requiring
critical care”.
Diagnostic evaluation of the critically ill nonhuman
primate involves both quantitative and qualitative moni-
toring. In addition to the objective measures previously
mentioned, additional quantitative information that may be
obtained depending on the needs of the individual animal
includes body weight, temperature, blood pressure,
complete blood count with reticulocyte and differential
leukocyte counts, serum biochemistry, urinalysis, pulse
oximetry, bone marrow analysis, cerebrospinal fluid (CSF)
analysis, rectal culture and sensitivity, central venous
pressure, and acid-base status. Additional qualitative
diagnostic testing may include imaging (radiography,
ultrasonography, endoscopy, CT), and ECG (
Lee, 2006
).
Diagnostic plans for common emergency conditions in
nonhuman primates can be found in the section “Emer-
gencies and diseases common to NHP requiring critical
care” below.
Use of in-house diagnostic laboratories is usually more
desirable than using outside laboratories because results
can be, theoretically, returned more quickly. For extremely
critical cases, point-of-care analyzers are capable of
measuring serum biochemistry, hematology, acid-base, and
coagulation parameters. These analyzers are especially
useful when instantaneous results are necessary and at
times when in-house laboratory services are unavailable.
Because critically ill nonhuman primates are often hypo-
glycemic on presentation, it is important to have a blood
glucose monitor readily available in the clinic environment.
Over-the-counter blood glucose monitors designed for
humans are inexpensive and work well for nonhuman
primate blood glucose measurements. It is advisable to
compare the results from the brand of blood glucose
measuring device you plan to use with measurements
derived from your clinical laboratory. More detail about the
diagnosis and treatment of hypoglycemia can be found in
the section “Emergencies and diseases common to NHPs
requiring critical care” below.
In many cases, full diagnostic capability requires the
combined use of point-of-care analyzers, in-house labora-
tories, and outside laboratories. It is likely that most in-
house laboratories will not have the capacity to perform all
diagnostic assays that may be required in the course of
treating nonhuman primates. Given the potential exposure
to biohazards that may be associated with handling
nonhuman primate samples, outside laboratories should be
identified in advance of need. Typically, the use of universal
precautions and bloodborne pathogen training of clinical
laboratory staff accustomed to working with human
samples is adequate, but additional training of personnel
may be required for specific biohazards encountered
naturally or experimentally in nonhuman primates. Once
outside laboratories that accept nonhuman primate bio-
logical samples have been identified, it may be necessary to
send samples from healthy animals in order to establish
a database of normal value ranges for the specific assays in
question. For most commonly used species of nonhuman
primates in the research setting, reagents used in human
assays will cross-react and are useful. Sending samples to
an outside laboratory for validation prior to an emergency
will assure that the human diagnostic assays are suitable for
use in nonhuman primates.
A comprehensive description of the techniques for
collection of diagnostic samples in nonhuman primates is
covered in detail in Chapter 13.
Pain Assessment and Management
In recent years, knowledge about the deleterious physio-
logical effects of acute and chronic pain, the pain pathway,
and pain management in the veterinary patient has
increased dramatically. Consequently, acute pain manage-
ment in the emergency patient has been recognized as
increasingly important. The assessment of pain should be
included as part of the primary survey of any critically ill
nonhuman primate (
Rudloff, 2004
).
