Biomedical Engineering Reference
In-Depth Information
useful for assessing the status and condition of the mother's
reproductive tract and may provide an immediate indica-
tion that caesarean section is indicated.
therapies so that a decision can be made to perform
caesarean section as early as possible.
Prior to performing a caesarean section, immediate life-
threatening problems, such as shock or severe electrolyte
abnormalities, should be addressed. During the procedure,
moistened laparotomy sponges should be placed under the
uterus to minimize spillage of uterine contents into the
abdominal cavity. If the cervix is closed, an attempt should
be made to remove fetal membranes and maternal decidua
by rubbing the endometrium gently with gauze sponges.
The uterus should be closed in two layers with the knots
buried to reduce the risk of abdominal adhesions. Oxytocin
may be given after the procedure in order to facilitate
uterine involution (
Traas, 2009
), and broad-spectrum anti-
biotics should be administered. Finally, because excessive
pain causes decreased food intake followed by decreased
milk production, adequate pain control is an important
consideration.
For nonhuman primate species that demonstrate
reproductive seasonality, awareness should be increased
during the birth season. For indoor-housed, breeding
nonhuman primates, it is feasible to diagnose pregnancy
well before the delivery date using ultrasound, abdominal
palpation, hormone assays, or supporting menstrual cycle
changes. Once pregnancy is diagnosed, a calendar should
be created so that enhanced observation can be instituted
close to parturition. For large breeding groups housed in
outdoor enclosures, there should be procedures in place
that require critical observation during the birth season of
all animals in groups where breeding age females and
males are housed. Births should be reported daily and
a system of identifying dams that have delivered should
be used to assist in decreasing the number of females that
need to be observed for dystocia as the birth season
progresses.
Treatment/Management/Prognosis
Medical management of dystocia includes the provision
of supportive therapy to stabilize the dam. If the fetus is
viable, supportive measures for the dam should be per-
formed concurrently with procedures to assist in the
birth of the fetus so as not to lose valuable time.
Animals with dystocia often experience volume deple-
tion due to blood loss and limited oral intake of fluids.
Intravenous fluid therapy, with or without the addition of
dextrose to treat hypoglycemia, should be instituted at
presentation to replace lost fluids and provide mainte-
nance requirements. If the animal's body temperature is
below normal, supplemental heat should be provided
using warm water re-circulating blankets or warm air
blankets. Calcium gluconate 10% (1 mg/kg i.v.; Cal-
ifornia National Primate Research Center (CaNPRC),
2009) should be administered subcutaneously to increase
the strength of uterine contractions. This is followed by
the administration of oxytocin at a dose of 5
20 U i.m.
or i.v. to increase the frequency of uterine contractions
(
Hawk et al., 2005; Davidson, 2009
). Current recom-
mendations in veterinary medicine are to use lower
oxytocin doses than historically recommended. Exces-
sive oxytocin is now known to cause tetanic contractions
that are unproductive and potentially harmful to the fetus
(
Davidson, 2009
).
If the fetus is malpositioned and easily manipulated,
manual repositioning and extraction may be attempted in
order to avoid caesarean section. If there is a danger of
injuring the reproductive tract or if manual extraction poses
an unacceptable risk of fetal injury, these techniques should
not be attempted. In most cases, attempts to reposition the
fetus with subsequent manual extraction are not successful
and the majority of cases of dystocia eventually result in
caesarean section (
Traas, 2009
). Because prolonged
dystocia is associated with decreased fetal survival, it is
best to err on the side of caution and perform a caesarean
section early if there is any doubt as to whether a successful
vaginal delivery is possible. There are several indications
for caesarean section, including fetal stress as indicated by
a sustained drop in fetal heart rate, failure of the dam to
respond to medical management, primary or secondary
uterine inertia, and suspicion of uterine rupture (
Traas,
2009
). Secondary inertia, in which the myometrium is too
fatigued to expel the fetus, is the most common maternal
cause for dystocia in companion animal medicine (
David-
son, 2009
). Response to supportive therapy, calcium
gluconate, and oxytocin should be assessed frequently to
quickly determine the effectiveness of
e
Orthopedic Emergencies
Open fractures are the type of orthopedic emergencies
that most often require emergency treatment and critical
care.
l
Clinical signs of orthopedic trauma include lameness,
angular deformity, and soft tissue swelling.
l
Prior to the orthopedic examination, a thorough physical
examination should be performed to identify injuries
involving systems other than those of a musculoskeletal
nature.
l
Radiographs should be taken in any case in which
orthopedic trauma is suspected, and culture and sensi-
tivity should be performed on any contaminated or
infected wounds.
l
Initial management should focus on reducing contami-
nation, immobilizing the limb, preserving vasculature,
and addressing pain.
l
these initial
