Objective—To investigate the in vitro effects of 3 hydroxyethyl starch (HES) solutions on viscoelastic coagulation testing and platelet function in horses.
Sample—Blood samples collected from 7 healthy adult horses.
Procedures—Blood samples were diluted with various crystalloid and HES solutions to approximate the dilution of blood in vivo that occurs with administration of a 10 and 20 mL/kg fluid bolus to a horse (1:8 and 1:4 dilutions, respectively). Diluted samples were analyzed through optical platelet aggregometry, platelet function analysis, thromboelastography, and dynamic viscoelastic coagulometry. Colloid osmotic pressure and concentrations of von Willebrand factor and factor VIII:C were also determined for each sample.
Results—For all HES products, at both dilutions, the colloid osmotic pressure was significantly higher than that in the respective carrier solutions. At the 1:4 dilution, nearly all HES solutions resulted in significant alterations in platelet function as measured via the platelet function analyzer and dynamic viscoelastic coagulometer. Significant decreases in platelet aggregation and factor concentrations were also evident. Fewer HES-associated changes were identified at the 1:8 dilutions.
Conclusions and Clinical Relevance—Dilution of blood samples with all HES solutions resulted in changes in viscoelastic coagulation and platelet function that did not appear to be attributable to dilution alone. In vivo evaluations are necessary to understand the clinical impact of these in vitro changes.
Objective—To evaluate the pharmacodynamic effects of dalteparin in dogs by means of viscoelastic coagulation monitoring with a thromboelastograph and a dynamic viscoelastic coagulometer.
Animals—6 healthy adult mixed-breed dogs.
Procedures—Dalteparin (175 U/kg, SC, q 12 h) was administered for 4 days (days 1 through 4). Viscoelastic coagulation monitoring was performed hourly on the first and last days of treatment and included intermittent measurement of anti–activated coagulation factor X activity (AXA).
Results—Dalteparin administration resulted in progressive hypocoagulability. On both day 1 and 4, activated clotting time and clot rate for the dynamic viscoelastic coagulometer differed significantly from baseline values, whereas the platelet function parameter did not change on day 1 but did on day 4. The R (reaction time), time from reaction time until the amplitude of the thromboelastography tracing is 20 mm, α-angle, and maximum amplitude differed from baseline values on days 1 and 4, although many thromboelastographic variables were not determined. The AXA was increased from baseline values at 3 and 6 hours after administration of the dalteparin injection on days 1 and 4, and all dogs had AXA values between 0.5 and 1.0 U/mL at 2 and 4 hours after administration. The AXA correlated well with activated clotting time (r = 0.761) and with R (r = 0.810), when values were available. Thromboelastography could not be used to distinguish AXA > 0.7 U/mL.
Conclusions and Clinical Relevance—Viscoelastic coagulation monitoring with strong coagulation activators may be used to monitor treatment with dalteparin in healthy dogs.
A 3-year-old 27-kg female spayed American Bulldog with severe burn injuries caused by a gasoline can explosion was evaluated.
The dog had extensive partial- and full-thickness burns with 50% of total body surface area affected. The burns involved the dorsum extending from the tail to approximately the 10th thoracic vertebra, left pelvic limb (involving 360° burns from the hip region to the tarsus), inguinal area bilaterally, right medial aspect of the thigh, and entire perineal region. Additional burns affected the margins of the pinnae and periocular regions, with severe corneal involvement bilaterally.
TREATMENT AND OUTCOME
The dog was hospitalized in the hospital’s intensive care unit for 78 days. Case management involved provision of aggressive multimodal analgesia, systemic support, and a combination of novel debridement and reconstructive techniques. Debridement was facilitated by traditional surgical techniques in combination with maggot treatment. Reconstructive surgeries involved 6 staged procedures along with the use of novel treatments including applications of widespread acellular fish (cod) skin graft and autologous skin cell suspension.
The outcome for the dog of the present report highlighted the successful use of maggot treatment and applications of acellular cod skin and autologous skin cell suspension along with aggressive systemic management and long-term multimodal analgesia with debridement and wound reconstruction for management of severe burn injuries encompassing 50% of an animal’s total body surface area.