Edited by Brady Pregerson, MD
Examination reveals a non-toxic, well-developed woman with an oral temperature of 97.7, a pulse of 86, a respiratory rate of 16 and a blood pressure of 171/110. Her oropharynx is clear without stridor, drooling or trismus, but she has noticeable left neck tenderness and edema just anterior to the sternocleidomastoid muscle. Cardiac and pulmonary examinations are normal, as is the remainder of her physical exam.
You perform a bedside ultrasound of the neck showing the left internal jugular to have multiple hyperechoic shadows, non-compressibility with the patient sitting or lying, and absent flow by Doppler, all compatible with a DVT. (Images 1 & 2 show the left IJ thrombosis and normal comparison view). Despite the emergency physician’s concern about radiation without justification, the admitting physician, a certified test-o-phile, orders a neck CT with contrast, which shows essentially the same thing the duplex did, a venous thrombosis involving the left internal jugular and external jugular veins with extension into the brachiocephalic vein. (Image 3) The patient is started on Lovenox, and is discharged home the next day to continue Lovenox for an additional 7 days along with Coumadin. A hypercoagulability work-up – protein C, protein S, homocysteine levels, lupus anticoagulant – returns negative.
Thrombosis of the internal jugular vein is an under-diagnosed condition that may occur as a complication of head and neck infections, surgery, central venous access, local malignancy, polycythemia, hyperhomocysteinemia, neck massage, and intravenous drug abuse. It is also reported to occur spontaneously. IJ thrombosis itself can have serious complications that include systemic sepsis, abscess formation, necrotizing fasciitis, chylothorax, papilledema, airway edema, and pulmonary embolism. The diagnosis often is very challenging and requires a high degree of clinical suspicion.
The symptoms and signs of IJ thrombosis can often be very subtle, making it easy to overlook the diagnosis. Pain and swelling at the angle of the jaw and a palpable cord beneath the sternocleidomastoid muscle both may be absent in a significant minority of patients. The thrombosis may become secondarily infected, producing a septic thrombophlebitis. Suppurative thrombophlebitis of the IJ vein that results from lateral pharyngeal infection is termed Lemierre’s syndrome. It is named after Dr. Andre Lemierre who reported 20 cases in 1936 prior to antibiotics. The disease process is biphasic with an initial pharyngitis followed 4-8 days later by IJ thrombosis, recurrence of fever, and sepsis. The infection spreads via local tissue planes, venules, or lymphatics leading to thrombophlebitis of the IJ vein. The usual organism is Fusobacterium necrophorum. Treatment consists of Penicillin and Flagyl. With widespread antibiotic usage this condition is fortunately now rarely seen.
Today, with extensive use of the IJ vein for venous access, central venous catheters are the most common underlying cause of IJ thrombosis. Individuals who abuse intravenous drugs can also present with IJ thrombosis secondary to repeated drug injection directly into the IJ vein. Other causes include local malignancy and head, neck, and cardiac surgery. Rare causes include polycythemia, hypercoagulable states and trauma. Spontaneous causes are often secondary to undiagnosed malignancy or a hypercoagulable state.
If the etiology of the IJ thrombosis is not obvious, then a more in-depth investigation of the coagulation system or a search for the cause of a hypercoagulable state should be performed. Currently available assays detect only 10-20% of inherited hypercoagulable states. The most common studies include measurement of levels of protein C, protein S, lupus anticoagulant, and resistance to activated protein C (factor V Leiden). Often a family history or past episodes of arterial thrombosis are present.
Diagnosis is usually made by duplex ultrasonography. Findings include a dilated and incompressible vein, intraluminal clot, no venous enlargement with the Valsalva maneuver, and abnormal Doppler flow. Contrast enhanced CT is considered to be the study of choice for suspected IJ thrombosis and its complications. It provides more information than ultrasound, but exposes the patient to the risks of contrast and radiation. CT scan can demonstrate low-density intraluminal thrombus, soft tissue swelling surrounding the IJ vein, and a distended IJ vein proximal to the thrombus.
Once a diagnosis is made, anticoagulant therapy is indicated to reduce the risk of pulmonary embolism, which is reported to be in the 1-5% range. Indwelling catheters should be removed. In the setting of infection, many patients do well with antibiotics alone with anticoagulant therapy added if there are septic emboli or evidence of clot propagation. Antibiotics should initially provide broad coverage with an emphasis on intra-oral organisms.