Pneumomediastinum after functional endoscopic sinus surgery under general anesthesia -A case report-
A 48-year-old female patient 158 cm in weight weighing 53 kg was admitted to receive functional endoscopic sinus surgery and septoplasty for a diagnosis of chronic sinusitis and nasal septal deviation. The patient was a non-smoker and her medical history stated that she had received an appendectomy one year prior to her visit and had a benign tumor removed from her bladder six months before her visit. There were no abnormalities other than light anemia with an Hb of 9.7 g/dl and Hct at 30.7% from the blood test.\nGlycopyrrolate 0.2 mg was IM injected as premedication, and preoxygenation was sufficiently achieved with 100% oxygen before induction of anesthesia. Propofol 100 mg and rocuronium 50 mg was slowly IV injected and after fully confirming loss of consciousness and muscle relaxation, oral endotracheal intubation was attempted with a curved laryngoscope (Macintosh size3 blade). The patient was class 1 based on the Cormack and Lehane laryngeal endoscopic classification, and endotracheal intubation was performed smoothly in the first attempt with a preformed Ring, Adair, Elwyn tube (RAE, Mallinckrodt) 7.0 mm in diameter. Proper placement of the tube was confirmed by chest auscultation and it was fixed at a tube length of 20 cm. A tidal volume of 450 ml and respiration rate of 12 times/min were maintained with mechanical ventilation (Aestiva/5®, Datex-Ohmeda, Madison, USA); airway pressure was 14-16 cmH2O and positive end expiratory pressure was 1 cmH2O. Anesthesia was maintained with O2 2 L/min, N2O 2 L/min, and sevoflurane 2.0-2.5 vol%. During surgery, the blood pressure was 105-150/60-95 mmHg, heart rate 75-100 beats/min, and oxygen saturation 99-100%, and end-tidal carbon dioxide tension was maintained at 33-37 mmHg. The duration of the surgery was 2 hours and 30 minutes, and there were no abnormalities during surgery. After surgery, pyridostigmine 15.0 mg and glycopyrrolate 0.4 mg were IV injected to reverse the muscle relaxation. When spontaneous respiration was sufficiently recovered and extubation of the endotracheal tube was about to be performed, suddenly, the patient severely shook her head and started to struggle so the bandage fixing the tube was immediately removed; air was removed from the balloon, and extubation was performed. During extubation, the patient was severely bucking while raising her neck and upper body so surrounding staff were called for help in safely holding down the patient. After extubation, the patient was soon stabilized after a few coughs and was moved to the recovery room. A blood pressure of 120-140/70-80 mmHg, heart rate of 65-76 beats/min, and oxygen saturation of 99-100% were maintained in the recovery room, and other than weak pain in the operated area, there were no specific complaints of symptoms so she was moved to general ward without abnormalities. Three hours after surgery, the patient started to feel nauseous and five hours after surgery, she vomited severely several times thus metoclopramide 10 mg was IV injected. Seven hours after surgery, the patient's neck and face swelled up with complaints of pain, and physical examination showed crepitation. Vital signs at the time was blood pressure 100/60 mmHg, heart rate 80 beats/min, respiration rate 20 times/min, temperature 36.3℃, and oxygen saturation 98%. Arterial blood gas analysis was immediately performed as well as chest and neck x-ray, and neck CT. The patient was put in semi-Fowler's position to provide oxygen 2 L/min through a nasal cannula, and was put on a fast. Results of arterial blood gas analysis showed pH 7.42, PaCO2 31.7 mmHg, PaO2 80.2 mmHg, HCO3- 20.7 mEq/L, and SaO2 96.8%. In the chest x-ray pneumothorax, subcutaneous emphysema in the chest wall, pneumomediastinum, and pneumoperitoneum were observed (). The neck CT showed extensive subcutaneous emphysema in the neck and face area, and emphysema in the retropharyngeal space (). The patient was immediately transferred to ICU and oxygen 5 L/min was provided through a mask in Fowler's position. No abnormalities were discovered in the fiberoptic laryngoscope examination performed by the ENT department when investigating the cause. 4 ml of air were extracted from the retropharyngeal space with an 18G needle using the intraoral approach, and the thoracic surgery performed insertion of chest tube on the right chest and incision of the subcutaneous emphysema on the chest wall. The patient received esophago gastro duodenoscopy (EGD) and bronchoscopy for differential diagnosis, and there were no abnormalities found in the EGD. In the bronchoscopy, there were no abnormalities in the laryngopharynx, vocal cords, and carina, but mucosal damage and bloody secretion were observed in the right second carina (). In the bronchial sputum examination, the patient was positive for mycobacterium tuberculosis polymerase chain reaction, and was diagnosed with tuberculosis. The patient received conservative treatment and anti-tubercular treatment, and was discharged from the hospital 2 weeks later with improved symptoms ().