Page 204 - Basic Monitoring in Canine and Feline Emergency Patients

canine teeth and a lower premolar removed earlier that there were no other abnormalities causing the
in the day at her primary care veterinarian’s office. clinical signs. The owners declined further workup
VetBooks.ir The CBC and chemistry panel performed prior to since her clinical condition had improved and the
chemistry panel preoperatively was normal and not
the dental procedure was normal. During the pro-
cedure, the site of the premolar extraction was
to her owners on a presumptive 3-week course of
bleeding slowly but continuously even after closure indicative of liver dysfunction. She was discharged
with a gingival flap and application of pressure. vitamin K and was reportedly doing well 2 days
Due to continued hemorrhage hours after the den- after discharge.
tal procedure, she was referred to the Teaching
Hospital for further diagnostics and care. The own-
ers reported no other abnormalities aside from a Case study 3: It is not the glaucoma…
historic exposure to anticoagulant rodenticide and Maui is a 10-year-old female spayed Chihuahua
recurrent dental disease. Per the owners, there was who presented initially for evaluation of changes to
no possibility of exposure to anticoagulant roden- her left eye – squinting, cloudiness, and possible
ticide in the last 2 weeks. Mini was on no medica- enlargement of the globe. The owner had noted
tions or supplements. these changes acutely during a flight home from
The CBC performed at the time of presentation vacation. During the evaluation of her eye by the
revealed a Hct of 30% (normal 40–45%) and a ophthalmology department, she was diagnosed
platelet count of 239,000/hpf (normal range with uveitis and glaucoma. As part of a workup for
200,000–300,000/hpf). The morphology of the uveitis, a CBC and chemistry panel were performed
platelets during microscopic examination was nor- where it was noted that her platelet count was low
mal. A PT/aPTT was also performed. The PT was with platelet clumping noted. An exact number was
prolonged at 43 seconds (normal 5.4–9.4 seconds). not available on the analyzer due to the clumping,
The aPTT was also prolonged at 27.5 seconds but there were at least 100,000 platelets/hpf (nor-
(normal 9.4–13.4 seconds). Both of these prolonga- mal 200,000–500,000/hpf).
tions were considered significant as they were Maui was discharged on ophthalmic medications
greater than twice the upper reference levels. The for her left eye and a recheck examination was
degree of prolongation of the PT (approximately scheduled for 1 month later during which a repeat
five times the upper reference interval) versus the platelet count was planned to confirm the throm-
degree of prolongation of the aPTT (around twice bocytopenia. At the time of her recheck examina-
the upper reference interval) was noted. tion, the owners reported that they had seen some
The exact cause of Mini’s hemorrhage was bruising in her left axilla and ventral thoracic
unclear but suspected to be a secondary hemostatic region. Two weeks prior to the recheck, Maui had
disorder based on the elevated PT/aPTT and the also undergone a dental procedure after the owners
normal platelet count. She had received both a spay noticed bleeding from one of her teeth. Only a
surgery and prior dental extractions in the past that cleaning had been performed without any teeth
did not cause excessive bleeding, making an inher- extractions, but no overt dental pathology was
ited thrombocytopathy less likely. Additionally, noted during the dental procedure to explain the
Mini had not received any drugs that might inhibit bleeding.
platelet function. During the physical examination at the time of
Mini was given a transfusion of fresh frozen presentation, besides the abnormalities reported by
plasma to provide functional clotting factors. She the owners, peri-umbilical ecchymoses, mild bruis-
was also started on oral vitamin K in the event that ing on the left flank fold, and petechiations above
she had been exposed to anticoagulant rodenticide the left upper canine tooth and on the right ear
without the owner’s knowledge (see Table 9.2 for were noted. A CBC revealed 6,000/μL platelets
rationale). Subsequent oral examination after the (normal 200,000–500,000/μL).
transfusion revealed a clot over the site of the tooth Maui was diagnosed with severe thrombocytope-
extraction. The following morning her PT and nia. Due to the profoundly decreased platelet count
aPTT were normal and her PCV had improved to and lack of indications of significant hemorrhage
35%. The owners were offered further diagnostics (PCV = 35%; normal 35–45%), she was presumed
including liver function testing and/or specific fac- to have immune-mediated thrombocytopenia. In
tor testing (e.g. factors VII, V, or X levels) to ensure order to look for an underlying cause of the

196 E.J. Thomovsky and A.C. Brooks