Page 303 - Feline Cardiology

Chapter 20: Arterial Thromboembolism 311

Physical examination
Rectal temperature and number
of limbs affected for prognosis

Initial diagnostics Emergency treatment
-Thoracic radiographs -Therapy for congestive heart failure
-ECG if arrhythmias or bradycardia if indicated by radiographs
-Serum chemistry (see CHF chapter for details)
-Urinalysis -Analgesia therapy

Follow-up diagnostics Short-term management
-Cardiology work up -Heart failure medications if indicated
-Thyroid status (depending on age) -Fluid therapy if indicated
-If no heart disease, search for -Heparin therapy
underlying cause of thromboembolism -Nutritional support
(i.e. neoplasia, etc.) -Rehabilitation therapy

Long-term management
-Cardiac medications if indicated
-Gradually discontinue heparin after
beginning long-term anticoagulant therapy
-Rehabilitation therapy Arterial Thromboembolism
-Wound management if ischemic necrosis

Figure 20.8. An algorithm for a clinical approach for cats presenting with ATE.

rial vasodilation is often not uniform and flow to muscle licking or chewing of the toes or hock. Application of a
beds may ultimately be unchanged. Also, these agents loose fitting bandage barrier is usually effective.
can cause hypotension. Their efficacy is therefore uncer- Appropriate clinical laboratory patient monitoring is
tain and their use has fallen out of favor. Hypothermia dependent on the individual’s status. Biochemical pro-
is a manifestation of poor systemic perfusion and shock files are useful to assess renal function and electrolyte
rather than just local blood flow changes due to a saddle status. Coagulation profiles (activated partial thrombo-
thrombus; improving it is one of the most important plastin time [aPTT], prothrombin time [PT], activated
goals in managing the acute crisis in ATE patients. clotting time [ACT], fibrin split products, platelet count)
However, addressing perfusion can be very difficult in are necessary to evaluate anticoagulation therapy and
these patients. Fluid therapy is warranted for dehydrated detect disseminated intravascular coagulation.
patients, as long as CHF is not present, but it must be Sudden hyperkalemia can result from reperfusion
used with caution in cats with significant heart disease. syndrome (ischemic rhabdomyolysis and reperfusion),
Vigilant monitoring of respiratory rate, effort and aus- which occurs when arterial blood flow is reestablished
cultation for the development of a gallop is particularly to a previously ischemic region, resulting in acute cata-
important in these patients. External warming can lead strophic release of potassium into the systemic circula-
to peripheral vasodilation and worsening of core perfu- tion (9.4% of cases in one study; Laste and Harpster
sion. Therefore it must be used cautiously for these 1995). Continuous recording of the ECG is one way to
patients. Excellent supportive care in the form of good screen for circulating potassium increases. Hyperkalemia
nutritional support, manual voiding of the urinary is usually associated with PR interval prolongation and
bladder if necessary, and maintaining clean and com- concurrent flattening and disappearance of the P waves,
fortable bedding is critical in this patient population. In widening of the QRS complexes, increasing T wave
some cats, a nasoesophageal feeding tube may be neces- amplitudes, and a slowing heart rate on the ECG.
sary for alimentation during the early stages of treat- In addition to the detection of hyperkalemia, the
ment. Self-mutilation of devitalized limbs occurs in a development of reperfusion syndrome can be identified
subset of patients and is characterized by excessive on clinical laboratory results by elevated blood lactate