Page 517 - Problem-Based Feline Medicine

23 – THE BLEEDING CAT 509

name, is it specific for a vitamin K dependent coagu- son is witnessed or suspected within several hours
lopathy. prior to consultation. (See Acute poisoning in The Cat
● Analytic confirmation of the poison in the blood is With Depression, Anorexia or Dehydration,
possible through some diagnostic laboratories. page 285). Examine vomitus for evidence of bait
(some are colored green) or a rodent; consider saving
vomitus for toxicologic analysis.
Differential diagnosis
● Administer an adsorbent and cathartic by stom-
Trauma, e.g. by a motor vehicle, can result in similar ach tube if the cat is sufficiently cooperative and:
patterns of hemorrhage and systemic signs. This is dif- – Examination of vomitus confirms ingestion and
ferentiated on the basis of evidence of injury (e.g. a toxic dose is suspected.
sheared nails, lacerations, fractured pelvis) and hemo- – Ingestion is known, induced vomiting did not
static testing. adequately eliminate poison, and it is less than
12 hours post-ingestion.
Differential diagnoses for bleeding at a specific site
– Ingestion is suspected, it is considered to be too
include local lesions at that site. These are differenti-
late to induce vomiting, and it is less than 12
ated on the basis of other signs of these processes and
hours post-ingestion.
normal hemostatic test results.
– Give a slurry of activated charcoal, 1.0–5.0
Liver and gastrointestinal diseases may result in vita- g/kg, preferably using a preparation that
min K deficiency, but the signs of the primary disease includes sorbitol as a cathartic. If activated
are present (e.g. jaundice, diarrhea) and are usually charcoal without cathartic is used, follow with
subacute to chronic. sodium sulfate, 1/2 level teaspoon per kg in
5–10 volumes of tepid water, by stomach
Fulminant DIC causing overt bleeding is not common
tube. If sorbitol or sodium sulfate is not avail-
in cats, and there will be clinical or laboratory signs of
able, use lactulose, 3 ml/kg PO.
an underlying disease. If in doubt, response to vitamin
● Measure PT at 48 and 72 hours and begin vitamin
K therapy rules out DIC.
K1 therapy if PT is prolonged. Obtaining a baseline
Hemophilia A, B and C are characterized by a normal PT may be helpful to facilitate detection of early
PT and prolonged aPTT. changes in PT. A less desirable alternative is to
measure baseline ACT and then at 72 and 96 hours,
Acute heart failure causes dyspnea and the same sys-
and begin vitamin K1 therapy if ACT is > baseline.
temic signs as acute hypovolemia due to hemorrhage,
● In some cases it may be less expensive or more con-
and nasal and oral cavity blood-tinged liquid may be
venient (e.g. cat is obstreperous in hospital) to
present. A heart murmur and arrhythmia may be pres-
empirically treat with vitamin K1 than to monitor
ent with both. Pulmonary crackles are more likely to
coagulation.
be caused by heart failure. Acute heart failure is more
common than anti-coagulant poisoning, and, while Vitamin K1. The synthetic product is phytonadione
radiographic pulmonary changes may be the same, which has the same activity as natural phylloquinone.
cardiomegaly is usually present with heart failure and ● The purpose of therapy is to provide a daily source
the heart may be smaller with hemorrhage. Echocar- of vitamin K until the toxin is eliminated and the
diography and hemostatic testing will definitively dis- vitamin K–vitamin K epoxide cycle can resume.
tinguish the two. Vitamin K1 is expensive but the small size of the
doses makes therapy less expensive in cats com-
pared to most dogs and allows empirical use of
Treatment
higher, longer doses.
Post-exposure treatment. ● Improvement in the PT is expected within 8–12
● Induce vomiting with xylazine, 0.44 mg/kg IM, or hours and normalization by 24–48 hours.
with hydrogen peroxide, 2 ml/kg, or syrup of ● Preferred route is PO as it has the best absorption.
ipecac, 3–6 ml/kg diluted 1:1 with water, PO or – The injectable products may be given orally.
preferably by stomach tube, if ingestion of the poi- Feed canned food as fat promotes absorption.