Case Description—A 3-year-old 19-kg (42-lb) spayed female mixed-breed dog was referred after being hit by a car. Injuries included pneumothorax, hemothorax, pulmonary contusions, a full-thickness axillary skin wound, and a grade I transverse fracture of the midshaft of the right humerus. Following patient stabilization, open reduction and internal fixation of the fracture were performed. The dog had weight-bearing lameness at the time of discharge. Eight days after fracture repair, the dog was reevaluated for acute onset of signs of pain and non–weight-bearing lameness in the right forelimb.
Clinical Findings—Physical examination findings in the right forelimb (knuckling and coolness, with absent digital pulses) were suggestive of a thrombus. Ultrasonography confirmed a right brachial artery thrombus with minimal blood flow to the affected limb.
Treatment and Outcome—Unfractionated heparin was administered via continuous IV infusion for the first 36 hours of hospitalization. Clopidogrel administration was also started at this time. During hospitalization, rapid clinical improvement occurred, and the dog was discharged 48 hours after admission. The transition to outpatient therapy was achieved by discontinuation of the unfractionated heparin infusion at 36 hours and beginning SC administration of dalteparin. Outpatient treatment with dalteparin and clopidogrel was continued. Repeated physical examination and ultrasonography 5 weeks later revealed resolution of the thrombus and normal blood flow to the limb. Anticoagulant administration was discontinued at that time.
Clinical Relevance—Thrombosis should be suspected in any dog with signs of acute pain after severe trauma or fracture repair, with or without concurrent lameness, that do not resolve with appropriate treatment. Restoration of blood flow to the affected limb after initiation of unfractionated heparin and clopidogrel administration followed by outpatient treatment with dalteparin and clopidogrel was achieved in this case.
Objective—To develop and assess the reproducibility of a protocol to noninvasively test endothelial function in dogs on the basis of the flow-mediated vasodilation (FMD) procedure used in humans.
Animals—5 healthy spayed female dogs.
Procedures—Luminal arterial diameter and blood flow velocity in the brachial and femoral arteries were measured with ultrasonography. The within-dog reproducibility of these ultrasonographic measurements was tested. An occlusion period of 1, 3, or 5 minutes with an inflatable cuff was used to create the FMD response. Measurements made at 15, 30, and 60 seconds following release of the occlusion were compared with measurements made immediately prior to each occlusion to assess the FMD response.
Results—Within-dog reproducibility of measurements revealed moderate to high correlations. Change from baseline in luminal arterial diameter was most substantial when measured at 30 seconds following release of occlusion, whereas blood flow velocity changes were maximal when measured at 15 seconds following release. The brachial imaging site provided a larger number of significant FMD responses than the femoral site. The 3-minute occlusion period provided equal or better responses than the 5-minute occlusion period.
Conclusions and Clinical Relevance—Ultrasonographic measurement of the FMD responses was a feasible and reproducible technique and significant changes from baseline were detected. The FMD responses in dogs were most substantial when performed at the brachial artery with blood flow velocity and luminal arterial diameter changes from baseline measured at 15 and 30 seconds, respectively, following release of a 3-minute occlusion period.
To develop a multivariable model and online decision-support calculator to aid in preoperative discrimination of benign from malignant splenic masses in dogs.
522 dogs that underwent splenectomy because of splenic masses.
A multivariable model was developed with preoperative clinical data obtained retrospectively from the records of 422 dogs that underwent splenectomy. Inclusion criteria were the availability of complete abdominal ultrasonographic examination images and splenic histologic slides or histology reports for review. Variables considered potentially predictive of splenic malignancy were analyzed. A receiver operating characteristic curve was created for the final multivariable model, and area under the curve was calculated. The model was externally validated with data from 100 dogs that underwent splenectomy subsequent to model development and was used to create an online calculator to estimate probability of splenic malignancy in individual dogs.
The final multivariable model contained 8 clinical variables used to estimate splenic malignancy probability: serum total protein concentration, presence (vs absence) of ≥ 2 nRBCs/100 WBCs, ultrasonographically assessed splenic mass diameter, number of liver nodules (0, 1, or ≥ 2), presence (vs absence) of multiple splenic masses or nodules, moderate to marked splenic mass inhomogeneity, moderate to marked abdominal effusion, and mesenteric, omental, or peritoneal nodules. Areas under the receiver operating characteristic curves for the development and validation populations were 0.80 and 0.78, respectively.
CONCLUSIONS AND CLINICAL RELEVANCE
The online calculator (T-STAT.net or T-STAT.org) developed in this study can be used as an aid to estimate the probability of malignancy in dogs with splenic masses and has potential to facilitate owners' decisions regarding splenectomy.