DIAGNOSTIC ALGORITHM FOR ACUTE SUPERIOR VENA-CAVAL OBSTRUCTION (SVCO)

Acute SVCO presents a serious diagnostic and therapeutic dilemma to th e thoracic surgeon. It is highly desirable to obtain a definitive tiss ue diagnosis but this requirement must be balanced against the risks i nherent in invasive diagnostic procedures in these oft-times criticall y ill patients. In the past 5 years we have developed an algorithm tha t has been used successfully in 18 patients presenting with acute SVCO . The decision tree consists of scalene node biopsy, bronchoscopy and mediastinoscopy with categorization into low and high risk groups in t he latter. The gender distribution of the 18 patients was 12 male and 6 female with the ages being 58.3+/-16.3 and 64.2+/-11.2 years respect ively. The duration of symptoms range from 1.5 to 12 weeks and average d 4.5+/-3.2 weeks. Two patients had palpable scalene nodes which were positive at biopsy. Bronchoscopy was positive in 5 out of 11 examinati ons. In 5 instances it was not done. Twelve patients underwent various forms of mediastinal biopsy and one underwent sternotomy. Seven patie nts requiring mediastinoscopy were judged to be high risk as defined b y severe airway and vascular obstruction. Perioperative difficulties o ccurred in two patients due to cardiorespiratory factors associated wi th the obstruction. Both patients were undergoing cervical mediastinos copy under general anesthesia and no difficulties were encountered in high risk patients when local anesthesia was used to perform anterior mediastinotomy. Five patients that were considered low risk all underw ent uncomplicated procedures under general anesthesia. Thirteen patien ts proved to have bronchogenic carcinoma and a specific tissue diagnos is was obtained in 12. The undetermined diagnosis was in a patient who had prior radiotherapy. In addition lymphoma, thymic carcinoma, semin oma, yolk sac carcinoma and thyroid goitre were established each in on e instance. A specific diagnosis was therefore found in 95% of cases. Anterior mediastinotomy under local anesthesia is a safe and highly ef fective method of obtaining a tissue diagnosis in acute SVCO.