Hypoxia: Hypoxia is a common sequel to birthing. Many newborns would benefit from short term supplemental oxygen therapy and respiratory
stimulants such as doxapram HCl. Those neonates with pneumonia or sepsis often require supplemental oxygen via an oxygen tent,
oxygen cage, nasal tube or face mask (short-term only). Arterial blood gases are nearly impossible to collect and unavailable
to most practices. However, a pulse- oxymeter can sometimes be placed on the hairless skin of the ventral abdomen. Unfortunately
an accurate reading requires adequate circulation not often present in a shocky neonate. The normal oxygen saturation is >
90%.
Dehydration: Dehydration is always a concern with a sick puppy or kitten. It is no surprise they are extremely susceptible to dehydration.
They are >70% water with a large surface area is covered with non-cornified skin combined with an inability to concentrate
their urine. Hydration status can not be accurately assessed with skin turgor. Estimates of the degree of dehydration must
be determined by dryness of the mucus membranes and eyes, plus the urine specific gravity. Accurate body weight and urine
specific gravity can be used to evaluate the rehydration efforts. Re-hydration fluids may be administered to the neonate orally
via stomach tube, subcutaneously, intravenously, interosseous, or rectally depending on the severity of the problem and resources
available. Regardless of the route, fluids should be pre-warmed to 95°F – 98.6°F. Maintenance fluid requirements in neonates
are about 60 -100 ml/kg/day.
For oral stomach tube fluid administrations use a 5 FR – 8 FR infant feeding tube. Measure from the tip of the nose to the
last rib and mark the tube. The tube is filled with fluid to prevent the introduce air into the stomach. Pass the tube down
the left side of the mouth as the puppy cries (exhales). After delivery of the fluid, pinch the tube prior to withdrawal and
withdraw it quickly to minimize aspiration. Aspiration pneumonia is a fatal consequence of improper placement of the feeding
tube. Normal stomach volume is approximately 50 ml/kg. Oral fluids and nutrition are contraindicated in hypothermic neonates
because gastrointestinal motility.
Subcutaneous fluids may be given in the interscapular space similar to a mature animal. However absorption is delayed with
hypothermia. The jugular vein may be catheterized for intravenous fluids using a 24-ga over-the-needle catheter. The interosseous
route is best method of fluid administration in the small neonate. A 22-ga spinal needle or standard 20 – 22-ga needle placed
intramedullary in the femoral cortex via the trochanteric fossa is an excellent way to administer fluids or blood. The site
should be clipped, aseptically prepared and blocked. The needle is rotated back and forth as it is pushed into and firmly
seated in the cortex. Pain is associated with cold fluids or fluids given to rapidly. The initial fluid of choice is warmed
50:50 solution of lactated ringers and 5% dextrose or LRS. Potassium supplementation may be necessary. Monitoring the patient's
weight, cardiopulmonary status, mucus membranes, and urine specific gravity can be used to evaluate the response to fluid
therapy.
Hypoglycemia: Next to hypothermia, hypoglycemia is one of the most common and serious problems seen in the neonates, especially the toy
breeds. Normal blood glucose for the neonate is 90-140 mg%. Maintenance of normal blood glucose requires several interrelated
factors of digestive absorption, liver and muscle glycogenolysis, and liver gluconeogenesis. A fasting puppy can maintain
adequate blood glucose for 24 hours initially through glycogenolysis then gluconeogenesis. After that period a precipitous
drop occurs. Neonates are prone to hypoglycemia because of increased demands for glucose (in part due to low fat reserves),
poor hepatic and muscle glycogen reserves and reduced precursors for gluconeogenesis. Hypoglycemia is often secondary or a
consequence of some other disease process (i.e. sepsis). Because it is such a common squeal to most problems empirical treatment
of hypoglycemia is recommended for all sick neonates. Clinical signs of hypoglycemia include; visual problems, vertigo, in
coordination, muscle tremors, seizures, lethargy, depression, collapse, coma, death. Unfortunately these symptoms can also
be associated with numerous other common and uncommon neonatal illnesses. The diagnosis of hypoglycemia is based on the clinical
signs, blood glucose, and the response to dextrose therapy. Therapy options include 10% Dextrose dosed at 1-2 ml/kg given
slowly intravenously or 1-2 ml/kg 10% dextrose given orally via stomach tube every 15 minutes until normoglycemic. Owners
can be instructed to give oral Nutrical, Nutri-Drops, honey, Kayro syrup but only if the patient is conscience. Once stabilized
initiate L-carnitine 50 mg/kg PO BID which increases the livers ability to convert fat into glucose. L-carnitine can be used
as a preventative in at risk patients.
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