Centrifugal therapeutic plasma exchange in dogs with immune-mediated hemolytic anemia (2016-2018): 7 cases

Objective To describe the technique of centrifugal therapeutic plasma exchange (cTPE) in dogs diagnosed with immune-mediated hemolytic anemia (IMHA) and summarize the outcome of the procedure. Design Retrospective review of cTPE performed at North Carolina State University from 2016 to 2018, through a search of the institutional database for cTPE and IMHA. Setting University teaching hospital. Animals Seven dogs with confirmed IMHA were presented to a university teaching hospital ICU for cTPE. Six dogs were not responsive to standard medical management with immunosuppressive agents, while 1 dog presented before immunosuppressive agents were begun. Interventions All dogs underwent multiple cTPE procedures using 1 of 2 commercially available apheresis systems. Measurements and Main Results At presentation, the median HCT was 0.15 L/L (15.7%) (range, 0.10-0.19 L/L [10.3%-19%]) and the median total serum bilirubin was 32.5 mmol/L (1.9 mg/dl) (range, 15.4-597 mmol/L [0.9-34.9 mg/dl]). The median number of transfusions before cTPE was 1 (range, 1-4), with a median total of infused RBCs of 12.9 ml/kg (range, 8.8-37 ml/kg). cTPE with an exchange of >= 4 times total plasma volumes was used to decrease the level of circulating autoreactive antibodies. The median total plasma volumes exchanged was 4.5 times (range, 2.5-6.5 times) over 2-4 procedures. Anticoagulation was performed using a combination of systemic heparinization and regional citrate in all dogs. Six of 7 dogs (85.7%) were discharged from the hospital and were alive 90 days after discharge. One dog (14%) did not respond to cTPE (similar to 6.5 times total plasma volume exchanged) and was euthanized. Conclusions cTPE is a feasible and relatively safe bridging treatment option for the management of canine IMHA.