A 60-year-old male had the symptoms of dyspnea, orthopnea, swelling in hands and feet, and cyanosis in lips and tongue for two months. He was admitted to a health-center and diagnosed with SVCS due to substernal goiter. After 2 days, his condition deteriorated, and he was admitted to emergency department of our hospital. On physical examination, excessive edema and cyanosis in upper chest wall and head-neck area were found out. His neck was short and thick with restricted movements. As he had developed dyspnea and arrhythmia, he was transferred to surgical intensive care unit. According to medical records, he had unsatisfactory sleep quality, excessive daytime sleepiness, severe snoring, and sleep apnea since 2 months ago. His body mass index (BMI) was 39 kg/m2, indicating obesity. Thyroid function tests revealed euthyroidism. His chest X-ray showed bilateral upper mediastinal enlargement and deviation of trachea (). Thorax computerized tomography (CT) revealed the deviation of trachea without obstruction, and compression of superior vena cava by the right lobe of thyroid gland. Previous polysomnography findings were obtained. Apnea-hypopnea index (AHI) was calculated as 26.7 episodes/h and nocturnal oxygen desaturation was documented as 65%. OSAS was diagnosed with the aid of polysomnography.\nAn urgent endotracheal intubation and mechanical ventilation were planned because of severe respiratory acidosis and hypercapnia (pH: 7.192, PaCO2: 145 mmHg, PaO2: 60 mmHg with 8 L/min nasal oxygen supplement). Following preoxygenation with 100% O2 via face mask, light anesthesia was induced with propofol, and laryngoscopy was applied without muscle relaxant. Spontaneous respiration was preserved after the administration of propofol. In the laryngoscopic assessment, Cormack and Lehane grade was considered as 4. The laryngeal Mask Airway (LMA) was placed promptly after failed endotracheal intubation. Mechanical ventilation was initiated through LMA and tracheostomy was performed uneventfully. The patient with SVCS was given antiedemal (steroid and diuretic), empiric antibiotic, and bronchodilator treatment in intensive care unit. Hence, his upper extremity and face-neck edema were reduced evidently. The steroid treatment was stopped, when nosocomial pneumonia was diagnosed on the 12th day. After the treatment of pneumonia, steroid treatment was restarted. The ventilatory mode was changed from synchronized intermittent mandatory ventilation (SIMV) to continuous positive airway pressure (CPAP) when arterial blood gas analysis revealed acceptable values (pH: 7.494, PaCO2 37.1 mmHg, PaO2 64.9 mmHg, HCO3 27.9 using FiO2 0.35) on the 35th day of mechanical ventilation. CPAP ventilation was applied for one week. Follow up T connector with oxygen supply was put on the tracheostomy cannula. Weaning was performed successfully on the 45th day.\nTracheal compression resulting from the enlargement of thyroid gland extending to substernal archus was detected in control CT after weaning (). The case was referred to thoracic surgeon, and he decided to perform thyroidectomy. The patient lost weight rapidly and thyroid function test indicated hyperthyroidism, which was attributed to the radiopaque agent used for CT. As soon as the result of thyroid function test returned to normal range, total thyroidectomy was performed successfully through collar incision and median sternotomy in elective conditions. Histopathological examination revealed a benign multinodular goiter. He was recovered and discharged from the hospital on the 14th postoperative day.
Case 3 involved a 78-year-old woman with a medical history of COPD, HT, and diabetes mellitus (DM). Her BMI score was 25.2kg/m2. She had presented to the emergency department with hypoxia, hypercapnia, tachypnea, and dyspnea, and was admitted to the ICU with a diagnosis of pneumonia. She was followed-up on in the ICU for five days, during the first two of which she was given NIMV support intermittently during the day and continuously at night. She received nasal O2 support for the following three days, and on day four she performed an apnea test between 00:00 and 06:00 am under an O2 mask (5L/min), which yielded the following results: AHI: 18/hr, AI: 8/hr, HI: 10/hr, ODI: 5/hr, min. SpO2 72%, and max. HR 102/min. It was decided that she should be scheduled to be discharged on bilevel positive airway pressure (BIPAP) support (Table ).