Acute Stridor and Respiratory Failure due to Retrosternal Subglottic Stenosis of Unknown Origin

Respiratory failure due to subglottic stenosis is a rare but serious condition. A 22-year-old male presented to the emergency department (ED) with shortness of breath, stridor, and change in tone of voice. The patient did not complain of B-symptoms (fever, weight loss, and night sweats). In the week before this presentation, he was diagnosed with an upper respiratory tract infection with associated bronchospasm and discharged on oral antibiotics and inhaled salbutamol without effect. He developed hypercapnic respiratory failure in the ED after a coughing episode. A normal nasopharyngoscopic examination and a subtle mediastinal abnormality on chest radiograph lead to a working diagnosis of retrosternal subglottic obstruction. The complexities of his airway management and suggestions for multidisciplinary approach are discussed. 1. Introduction Respiratory failure due to subglottic stenosis is a rare but serious condition. There are no guidelines for distal, retrosternal airway stenosis. 2. Case Report A 22-year-old man of Mediterranean descent presented by ambulance to the ED complaining of intermittent coughing associated with severe shortness of breath, stridor, and change of voice tone. Two episodes of altered level of consciousness, associated with incontinence and cyanosis, were reported prehospitally before paramedic assessment. On arrival in ED, he was alert, with oxygen saturations of 88% on room air and a respiratory rate of 60. Further history revealed that he had been assessed in two other EDs in the preceding fortnight and discharged with a working diagnosis of upper respiratory tract infection with associated bronchospasm. He was discharged 4 days previously on oral roxithromycin and inhaled salbutamol. There was no improvement of symptoms since and he suffered paroxysmal coughing episodes triggering severe dyspnoea. He had no significant past medical history and he did not take any regular medications. He was a nonsmoker, who denied any illicit drug use. He was a pharmacy student with no relevant family history. After initial assessment in ED, his respiratory parameters improved to an oxygen saturation of 99% on room air and a respiratory rate of 26/min; however, a repeat episode of coughing again lead to diaphoresis, stridor, and respiratory rate of 60/min with oxygen saturations of 88% on room air. High-flow oxygen was administered and an arterial blood gas was taken, which showed acute hypercapnic respiratory failure (PH: 7.17, PCO2: 77, PO2: 102, and HCO3: 27). The patient was treated with nebulised adrenalin and urgent