Page 977 - Problem-Based Feline Medicine

44 – THE CAT WITH GENERALIZED WEAKNESS 969

diabetic neuropathies. Persistent hyperglycaemia above Hypothermia may be associated with up-regulation
16 mmol/L (288 mg/dl) is diagnostic of diabetes. of anti-inflammatory cytokine activity. Cardiac
insufficiency is common, and coagulopathies often
Other neuropathies (e.g. neoplastic, idiopathic, inflam-
ensue.
matory) are not associated with persistent fasting
hyperlipidemia. Bradycardia is an inappropriate response to critical
illness, and its mechanism is unknown. Increased vagal
tone, sympathetic stimulation, and induction via hypo-
Treatment
thermia have all been postulated to be involved. It may
Feeding a low-fat diet resulted in resolution of the neu- be exacerbated by hypoglycemia or hyperkalemia
ropathy in 2–3 months in a few cats with peripheral which may accompany the septic state.
neuropathy.
Depression of myocardial function is exacerbated
Gemfibrozil (7.5–10 mg/kg daily) is indicated if by hypothermia, and continues after rewarming.
dietary therapy does not normalize triglyceride concen- Intracellular calcium overload contributes to diastolic
trations. dysfunction. Systolic dysfunction occurs secondary to
ischemia, myocardial edema or infarction.
Marine (fish) oils rich in omega-3 fatty acids may help
to decrease triglyceride concentrations. Cytokines increase vascular permeability and hypoal-
buminemia reduces oncotic pressure. When combined
with depressed myocardial function, the septic cat is
susceptible to fluid overload during treatment for
ACUTE SEPSIS
hypovolemia.
Classical signs Anemia results in local hypoxia and local lactic acidosis.
● Generalized weakness or flaccid paralysis.
● Hypothermia.
● Tachypnea. Clinical signs
● Bradycardia.
Depression and anorexia are typically present, and if
● Hypotension (poor pulses, pale mucous
sepsis is severe, the cat may be profoundly weak or
membranes, increased capillary refill
collapsed.
time).
Pyrexia or hypothermia may be present
Signs suggesting the infection site such as dyspnea,
Pathogenesis vaginal discharge or uterine distention, abdominal
guarding, or skin abscess are often evident.
Toxemia and reduced tissue oxygenation from acute
bacterial sepsis may cause weakness and depression. The classic signs of sepsis, labeled the “sepsis triad”
(fever, tachycardia, tachypnea) or the hyperdynamic
Toxemia may be associated with bacteremias originat-
phase, are rarely recognized.
ing in the uterus (pyometritis), thorax (pyothorax),
abdomen (peritonitis) or skin (subcutaneous abscess). Sepsis in cats often presents as the “shock triad”
(hypotension, bradycardia, hypothermia). Hypotension
Pyrexia or hypothermia may be present, and signs
is evidenced as poor pulses, pale mucous membranes
referable to the infection site are often evident includ-
and increased capillary refill time.
ing dyspnea, vaginal discharge, abdominal guarding or
skin abscess. Localized infection will often cause pyrexia, but sepsis
often presents at a stage where fever is no longer sus-
Hypothermia weakens the immune system, depres-
tained and hypothermia has developed.
ses the myocardium, bluntens the vasculature response
to catecholamines and reduces cellular function. Heart rate often follows temperature.