Page 492 - Cote clinical veterinary advisor dogs and cats 4th

Cranial Vena Cava Syndrome 221

patients. No measures have been identified discuss with owners of puppies intended for SUGGESTED READING
to prevent this from occurring. • Maintaining lean body weight may be Kowaleski MP, et al: Stifle joint. In Johnston SA, et
high-performance work.
VetBooks.ir orthopedic surgeon; selection of the best Technician Tips AUTHOR & EDITOR: Kathleen Linn, DVM, MS, DACVS Diseases and Disorders
• Consider consultation and referral with an
al, editors: Veterinary surgery: small animal, ed 2,
beneficial.
St. Louis, 2018, Elsevier, pp 1079-1141.
procedure continues to be controversial
among specialists.
Most dogs should be partially weight bearing
Prevention on the operated limb by the end of the first
• No reliable preventive measures have been postoperative day. Dogs who have had epidural
identified. Because several recent studies have analgesia for stifle surgery may require bladder
implicated ovariohysterectomy as a risk factor expression for up to 24 hours.
for CrCL rupture, this may be a point to

Cranial Vena Cava Syndrome Client Education
Sheet

BASIC INFORMATION PHYSICAL EXAM FINDINGS • Myxedema (e.g., secondary to hypothyroidism)
• Symmetrical, nonpainful pitting edema of • Foreign body around neck (e.g., elastic band)
Definition head, neck, and forelimbs • Salivary mucocele (cervical)
Cranial vena cava syndrome is an uncommon • Dyspnea, tachypnea, muffled heart/lung • Jugular vein thrombosis or mass
sequela to extraluminal compression, invasion, sounds (if pleural effusion present) • Abscessation or cellulitis
or intraluminal obstruction of the cranial • Weakness, tachycardia, arrhythmias, muffled • Snake bite
vena cava (CrVC). Obstruction of the CrVC heart sounds (if pericardial effusion present)
results in pitting edema of the head, neck, and • ± Jugular venous distention Initial Database
forelimbs. • ± Engorgement of conjunctival and scleral To help determine underlying cause:
vessels • CBC
Synonyms • Additional physical exam findings depend • Serum biochemistry profile
Caval syndrome, precaval syndrome, superior on underlying cause. • Urinalysis
vena caval syndrome • Feline leukemia and feline immunodeficiency
Etiology and Pathophysiology virus tests (to help evaluate for lymphoma
Epidemiology • Extraluminal compression, invasion, or in cats)
SPECIES, AGE, SEX intraluminal obstruction of the CrVC • Thoracic radiographs (to identify cranial
Depends on underlying cause causes impaired venous return from the mediastinal masses, pleural and/or pericardial
cranial portion of the body. This leads to effusion)
RISK FACTORS interstitial fluid accumulation, resulting in
• Jugular catheters edema of the head, neck, and forelimbs. Advanced or Confirmatory Testing
• Cranial mediastinal neoplasia (e.g., thymoma, • The most common causes include mediastinal • Thoracic ultrasonography (to visualize emboli
lymphoma, carcinoma, aortic body tumors, neoplasia, fungal granulomas, CrvC throm- or tumor compression/invasion of cranial
pleural mesothelioma) bosis (e.g., secondary to hypercoagulable vena cava)
• Hypercoagulable conditions (e.g., sepsis, states, tumor emboli, jugular catheters), and • Nonselective angiography, venography (to
immune-mediated hemolytic anemia, transvenous pacemaker implantation. identify CrVC filling defects, localize site of
protein-losing nephropathies, glucocorticoid obstruction, highlight collateral circulation)
excess, neoplasia, pancreatitis) DIAGNOSIS • CT or MRI (p. 1132)
• Mycoses leading to the formation of granu- ○ CT-angiography has been used to diagnose
lomas (e.g., blastomycosis, cryptococcosis) Diagnostic Overview acquired collateral venous pathways in a
• Transvenous pacemaker implantation The physical exam findings (pitting edema dog with CrvC.
of the head and forelimbs) are highly sugges- • Echocardiography (p. 1094); (to identify
CONTAGION AND ZOONOSIS tive of the diagnosis. Diagnostic tests such pericardial effusion or masses at the level
Fungal granulomas causing CrVC syndrome as thoracic radiographs, advanced imaging, of the terminal CrVC)
may be caused by organisms that can also infect cytologic evaluation of masses and effusions, and • Fine-needle aspiration or biopsy of thoracic
humans (Blastomyces dermatitidis, Cryptococcus histopathologic examination of tissue specimens masses
neoformans), but they would be common-source are used in sequential steps to confirm the • Additional testing as indicated by suspected
infections, not zoonoses. diagnosis and identify the underlying cause. underlying cause (e.g., Blastomyces urine
antigen test if Blastomyces granuloma suspected)
GEOGRAPHY AND SEASONALITY Differential Diagnosis • Thromboelastography (TEG) can be used to
Infectious causes (e.g., blastomycosis, cryptococ- For head and neck swelling: assess hypercoagulable state and aid in guidance
cosis) are more prevalent in certain geographic • Angioedema (e.g., vaccine reaction, insect- of thromboprohylaxis or thrombolytic therapy.
areas. bite hypersensitivity)
• Generalized peripheral edema (e.g., secondary TREATMENT
Clinical Presentation to hypoalbuminemia, vasculitis, right-sided
HISTORY, CHIEF COMPLAINT congestive heart failure) Treatment Overview
• Head, neck, and forelimb swelling • Acute blunt trauma to head/neck Treatment is directed toward removing the
• Additional clinical signs depend on underly- • Subcutaneous emphysema obstructive lesion from CrVC and treating
ing cause. • Lymphangiosarcoma of the head and neck the inciting cause.
www.ExpertConsult.com