Apheresis in three dogs weighing <14 kg

Area of Science:

• Veterinary Medicine
• Hematology
• Critical Care

Background:

• Apheresis machines require a significant priming volume, typically limiting the procedure to larger dogs (>20 kg) to avoid excessive blood volume removal (<20%).
• Smaller dogs present a challenge for apheresis due to the risk of hypovolemia from the machine's extracorporeal priming volume.

Purpose of the Study:

• To evaluate the feasibility and safety of apheresis in small dogs (<14 kg) with lymphoma.
• To assess the efficacy of different priming solutions and sedation protocols in this patient population.

Main Methods:

• Three client-owned dogs weighing <14 kg with lymphoma underwent apheresis.
• Anesthesia involved hydromorphone premedication, propofol induction, isoflurane maintenance, and sedation with dexmedetomidine or propofol constant rate infusion (CRI).
• Priming solutions included hetastarch, lactated Ringer's solution, and/or previously harvested autologous blood. Anticoagulant citrate-dextrose, solution-A (ACD-A) and calcium gluconate were administered during the procedure. Cardiovascular and cardiopulmonary parameters, anemia, and lactic acidosis were monitored.

Main Results:

• All dogs maintained clinically acceptable cardiovascular and cardiopulmonary values throughout the apheresis procedure.
• Post-apheresis, dogs experienced mild to moderate anemia (PCV 17-35%) but did not require transfusions.
• No dogs developed increased lactate concentrations, indicating absence of significant lactic acidosis.

Conclusions:

• Apheresis is a viable procedure for dogs weighing as little as 9.9 kg.
• A variety of priming solutions can be safely used.
• Dexmedetomidine or propofol administered as a CRI provides adequate sedation for apheresis in small dogs.