Page 127 - Problem-Based Feline Medicine

8 – THE CYANOTIC CAT 119

Signs of cardiac failure include dyspnoea, cardiac mur- therapy includes cage rest where necessary, weight reduc-
mur, gallop rhythm, slow capillary refill time, pale/cyan- tion, avoidance of pregnancy and general reduction in car-
otic mucous membranes and pulse deficits. diac workload. See page 130 (The Cat With Abnormal
Heart Sounds and/or an Enlarged Heart) for treatment.
Evidence of shock, trauma, pyrexia, blood loss or
reduced urinary output may indicate cause of periph- For shock, treatment depends on the cause. For
eral vasoconstriction. hypovolemia administer intravenous fluids, and if indi-
cated, a blood transfusion and control any continuing
History of frequent or severe vomiting, diarrhea or
blood loss. For septic shock, fluid therapy and intra-
diuresis are suggestive of marked fluid loss leading to
venous broad-spectrum antibiotic therapy is indicated.
hypovolemia.
For anaphylactic shock, in addition to fluid therapy,
Fluid accumulations in the thoracic or abdominal cavi- epinephrine is of proven efficacy. Careful monitoring
ties or in intracellular spaces suggest cardiac disease, of acid–base balance, urine output, heart rate, pulse
sepsis, bleeding or severe hypoalbuminemia is the cause quality, capillary refill time, mucous membrane color
of the vasoconstriction and cyanosis. and mental state are important. The reader is advised
to consult a specialist source for an in-depth review of
Acute weakness, bradycardia and cyanosis, with or
shock therapy.
without a history of polyuria/polydipsia or GIT signs,
in a young to middle-aged dog is suggestive of hypo- Rewarming is required for hypothermia. When the
adrenocorticism (Addisons disease). body temperature is less than 32 degrees Centigrade
(90 degrees Fahrenheit) active central rewarming is
required. This includes the use of warmed (to 35
Diagnosis degrees Centigrade/95 degrees Fahrenheit) IV fluids,
flushing stomach, rectum and open body cavity with
Diagnosis is based on clinical signs and physical
warmed isotonic fluids, and providing warmed,
findings which suggest that hypovolemia, severe car-
humidified air. If body temperature is between 32 and
diac disease, sepsis or hypothermia are causing
36 degrees Centigrade (90 and 96 degrees Fahrenheit)
marked vasoconstriction and generalized peripheral
active surface rewarming can be carried out using hot
cyanosis.
water bottles, heat pads, radiant heaters and hair dryers.
Cardiovascular examination, including echocardiogra- At body temperatures above 36 degrees Centigrade (96
phy are important in assessing cardiac function. degrees Fahrenheit) passive rewarming by covering the
cat with blankets is sufficient.
Complete blood profile may indicate sepsis or hypov-
olemia.
Thoracic and abdominal radiographs may show car- Prognosis
diomegaly, fluid accumulations, evidence of hypov-
olemia, evidence of trauma or masses such as With hypovolemia recovery rates can be high, provid-
abscesses. ing adequate correction of fluid deficits can be
achieved.
Cardiogenic shock is usually associated with advanced
Treatment
heart disease and so recovery rates are less.
For cardiogenic shock, treatment is directed at restoring
Mortality rates in septic shock are high.
organ perfusion to provide adequate tissue oxygenation,
i.e. supporting arterial blood pressure, forward cardiac The systemic consequences of mild to moderate
output and vascular volume. Diuresis, vasodilation, cal- hypothermia are minimal but those of severe pro-
cium channel- or beta-blocking drugs, anti-arrhythmics, longed hypothermia are serious and fraught with many
oxygen and thoracocentesis may be required in hyper- complications including cardiac arrhythmias, elec-
trophic cardiomyopathy. Continuous monitoring of car- trolyte disturbances, coagulopathies, blood glucose
diac, pulmonary and renal status is essential. Supportive upset and cold diuresis.