Page 299 - Problem-Based Feline Medicine

16 – THE CAT WITH ACUTE DEPRESSION, ANOREXIA OR DEHYDRATION 291

Prompt intravenous fluid therapy. This is critical for Elapidae also have hematoxins that activate and deplete
a good prognosis. clotting factors resulting in bleeding, myotoxins that
cause rhabdomyolysis, or hemolysins that cause
Dehydration is an important mechanism in the
intravascular hemolysis.
development of renal failure. Prompt initiation of
intravenous fluids will halt progression of non-oliguric Venoms from Viperidae are predominantly hematoxic,
to oliguric/anuric renal failure and hasten recovery. although some have neurotoxic properties. Edema ±
Deliver fluids at 2–3 times maintenance for a mini- bleeding/bruising around the bite is typical.
mum of 24 hours (48 hours preferred).
Venoms from Crotalidae are predominantly hematoxic,
Gastrointestinal decontamination and intravenous although some are potent neurotoxins. Acute depres-
fluid therapy within 6 hours of ingestion is likely to pre- sion may occur from hypotension or neurotoxicity.
vent renal failure. If such treatment is delayed for more
Venoms from most Colubridae are mild and clinical
than 18–24 hours, acute renal failure will likely occur.
reports of bites to cats lacking.
If renal failure occurs, see Acute renal failure, above.
● Hemodialysis and peritoneal dialysis have been
used to support cats through oliguric/anuric renal
Diagnosis
failure until tubular regeneration occurs. Without
dialysis, the prognosis for oliguric/anuric renal fail- Diagnosis is based on history of possible exposure to
ure is grave. Cats with non-oliguric acute renal fail- a snake and physical examination findings.
ure may develop chronic renal failure.
CBC may reveal hemoconcentration, echinocytosis and
thrombocytopenia. Serum chemistry profile may reveal
SNAKE BITE ENVENOMATION* hypokalemia and elevated CK, ALT, urea and creati-
nine levels. Urinalysis may reveal myoglobiunuria or
Classical signs hemoglobinuria and glucosuria.
● Flaccid paresis/paralysis with mydriasis
(most Elapidae, some Crotalidae and
Viperidae snakes). Differential diagnosis
● Bleeding tendency (some Elapidae and
See The Cat With Generlized Weakness (page 952) and
Viperidae snakes).
for differential diagnosis of neurologic signs and The
● Bite wound on cranial half of body ± local
Bleeding Cat (page 503) for differential diagnosis of
swelling or bleeding (Viperidae snakes).
hematologic signs.
See main reference on page 950 for details (The Cat Differential diagnoses for the local reaction include
With Generalized Weakness). angioedema from insect envenomation, animal bite
wounds, sharp and blunt trauma.

Clinical signs
Treatment
Cats are less likely to be bitten than dogs.
Keep the animal calm.
Venoms from Elapidae snakes (all Australian snakes)
are predominantly neurotoxic. Initial signs may be Supportive care. See page 953, The Cat With
acute depression and weakness. More specific signs Generalized Weakness.
include areflexic dilated pupils, dysphagia (salivation),
Specific antivenin therapy.
dyspnea (respiratory paralysis), hindlimb ataxia and
flaccid quadraplegia. Local reaction to the bite is mini- Transfusions for clinically significant hemostatic or
mal, and the bite wound is rarely located. Some hematologic abnormalities.