Clinical findings:
(1) congestion and cyanosis of the head, neck and upper extremities, with no congestion in the abdomen, pelvis or lower extremities
(2) swelling with a feeling of fullness of the head, neck and upper extremities with no swelling in the lower extremities
(3) respiratory symptoms:
(3a) dyspnea with or without respiratory distress
(3b) cough
(3c) hemoptysis
(4) tracheal symptoms
(4a) hoarseness or dysphonia
(4b) tracheal obstruction with stridor
(5) chest pain
(6) dysphagia
(7) visual disturbances and conjunctival edema
(8) cerebral symptoms (associated with venous hypertension
(8a) headache
(8b) somnolence or altered mental status
(8c) syncope when bending
(8d) dizziness
(8e) seizures
(9) cervical venous distention
The severity of the congestion is affected by:
(1) how complete the obstruction is
(2) how fast it developed
(3) how well the blood is able to shunt through collateral vessels (azygous, internal mammary, laterothoracic, or vertebral veins)
Imaging studies may show:
(1) a widened superior mediastinum
(2) pleural effusions
If the syndrome is caused by a large tumor, then other structures such as a bronchus or the esophagus may become obstructed.
