The dog received intravenous fluid therapy and antibiotics to treat possible aspiration pneumonia. Before initiating therapy,
a transtracheal wash was performed and submitted for cytologic evaluation and culture. Blood was collected for a complete
blood count (CBC) and a serum chemistry profile. The dog was then treated with ampicillin (22 mg/kg intravenously q.i.d.)
and amikacin (20 mg/kg intravenously once a day) as well as nebulization with water vapor and coupage every six hours.
The dog's attitude and activity improved during the first 24 hours of therapy, and it ate well in the hospital. There was
no spontaneous coughing or dyspnea observed.
ADDITIONAL DIAGNOSTIC TESTS
The CBC identified a mild neutrophilia (8.4 x 109/µl; reference range = 3 to 10 x 109/µl) and a mild slightly regenerative anemia (hematocrit = 0.363 L/L [reference range = 0.365 to 0.573 L/L]; hemoglobin= 125
g/L [reference range = 128 to 196 g/L]; reticulocytes 2.6%, 1+ polychromasia). The serum chemistry profile results were unremarkable.
Transtracheal wash cytologic examination results showed a few individual and clusters of respiratory epithelial cells and
rare macrophages enmeshed in mucoid material. On cytospin preparation, a moderate number of respiratory epithelial cells and
erythrocytes and a few foamy macrophages were noted, some of which contained hemosiderin, suggesting ongoing intrapulmonary
hemorrhage. Neutrophils were rare, no infectious organisms were noted, and the bacterial culture results were negative.
Given the lack of marked inflammation or infectious organisms, the presence of a regenerative anemia, and the identification
of hemosiderophages on the tracheal wash, we considered it most likely that the patient was bleeding into the lung parenchyma.
Prothrombin time and partial thromboplastin times were normal.
A radiographic examination was repeated two days after admission. The dog was clinically normal with no respiratory signs
and normal appetite and activity. The opacity of the left cranial lung lobe was essentially unchanged, with subtle improvement
in aeration of that lung. An ultrasonographic examination of the left cranial lung revealed no air present within the parenchyma
or bronchi with little vascular supply evident, although cardiac motion interfered with Doppler detection of blood flow. No
pleural fluid was evident.
The radiography and ultrasonography results together with the results of the tracheal wash made lung lobe torsion most likely.
Computed tomography (CT) was recommended for further evaluation.
Precontrast and postcontrast CT of the thorax with axial 1-mm slices was performed, beginning in the caudal cervical region
and extending caudally to mid abdomen.
There was marked soft tissue opacification of the left cranial lung lobe and compression of the bronchus, leading to the left
cranial lung lobe.
The left cranial lung lobe was larger than normal, suggesting probable vascular congestion and strongly supporting a diagnosis
of lung lobe torsion.
Multiple air opacities were noted medially, which most likely represented air entrapment within bronchioles or the alveoli.
2. A postcontrast transverse image from thoracic CT of the dog in this report. Marked soft tissue opacification of the left
cranial lung lobe (indicated by *) and compression of the bronchus (arrow) are noted leading to the left cranial lung lobe.
The appearance of the lung tissue lateral to the opacified lung is consistent with atelectasis.
No vascular supply was noted coming into or going from the affected lung lobe; whereas, vascularity was noted in the other
lung lobes (Figures 2-4). Lung lobe torsion was the probable diagnosis, and surgery was scheduled.
3. A 3-D reconstruction from postcontrast thoracic CT of the dog in this report. The compression and complete attenuation
of the bronchus to the left cranial lung lobe is readily visible (arrow). No aeration and vascularity are visible in the left
cranial lung lobe compared with the other lung lobes.
The patient was premedicated with hydromorphone (0.1 mg/kg intravenously) and induced with alfaxalone (2 mg/kg intravenously).
Before intubation, flexible bronchoscopy was performed.
4. A dorsal multiplanar reconstruction image from thoracic CT of the dog in this report. The compression and attenuation of
the bronchus to the left cranial lung lobe (LCL) is clearly visible (arrow). The left cranial lung lobe is completely opacified.
(The heart is labeled with an H.)
Results of the bronchoscopic evaluation of the right lung and the left caudal lung lobes were normal. The bronchi of the cranial
and caudal portions of the left cranial lung lobe were twisted closed, confirming lung lobe torsion (Figure 5).
5. A bronchoscopic evaluation of the dog in this report showed a normal right lung and normal left caudal lung lobes. The
bronchi of the cranial and caudal portions of the left cranial lung lobe were twisted closed (arrow), confirming lung lobe
After the bronchoscopic evaluation, the patient was prepared for surgery. The patient was intubated, and anesthesia was maintained
through inhaled isoflurane and oxygen. Cefazolin (22 mg/kg intravenously) was administered after induction and continued every
90 minutes during surgery.