Case Report of Awake Nonintubated Anterior Mediastinal Mass Excision in a New Tertiary Care Institute

CASE REPORT

A 30-year-old male presented with complains of moderate chest pain for 1 month, localized in the retrosternum, which aggravated on exertion, and was not associated with radiation, and breathlessness. He had a history of inflammatory bowel disease for the last 5 years and was on irregular medication. During the follow-up visit, a contrast-enhanced computerized tomography scan revealed an anterior mediastinal mass [Figure 1]. The biopsy ruled out the germ cell tumor and confirmed it to be thymoma. It was a well-circumscribed lesion measuring around 90 mm x 56 mm x 30 mm. It did not compress the trachea but was extending up to the arch of the aorta and adherent to it. Hence, it was planned to excise the mass with a diagnostic and curative intent. On preoperative evaluation, complete blood count, renal function test, liver function test, and coagulation profile were within normal ranges. The patient was counseled by the surgeon and anesthesiologist together and the plan of awake surgery was explained in depth and all queries of patient and relatives were resolved. On the evening before surgery, a written and well-informed consent was taken by the patient. He was advised tablet alprazolam 0.5 mg on the night before and in the morning of surgery to alleviate anxiety.

Minimum staff were allowed during the preoperative and intraoperative period to keep the operative room (OR) environment calm. The patient was shifted to OR and electrocardiogram, pulse oximetry, invasive blood pressure in the right femoral artery and two intravenous (IV) access with 16 G cannula were secured. The patient lied down on the operating table and adjusted to OR environment. 1 mg of Midazolam was administered intravenously to decrease anxiety followed by an intramuscular injection of Morphine 0.1 mg/kg. The upper posterior thoracic region was cleaned and draped in sitting position and 18 G epidural was placed at the level of T1-T2 by loss of resistance technique. The epidural catheter was inserted 4 cm into the epidural space. A mixture of local anaesthetic solution consisting of 5 ml lignocaine 2%, 10 ml Bupivacaine 0.5% and 25 µg fentanyl was administered over 5 min. The sensory and motor blockade was checked with cold saline and pinprick method. The level of anesthesia was achieved till T8 level as desired for sternotomy. Oxygen was given via nasal prongs at the rate of 2 l/min. There was a decrease in heart rate and blood pressure but was <20% of baseline values. This was expected after sympathetic blockade due to regional anesthesia. Atropine and Mephenteramine were loaded and two iv fluids in pressure bags were connected to peripheral iv lines to manage any significant hemodynamic change. The operating team constantly communicated and reassured the patient. There was a back-up of the supraglottic airway and flexo-metallic endotracheal tube in OR. In addition, an ENT specialist was called to standby with a rigid bronchoscope to secure the airway in the scenario of not able to ventilate or intubate. After midline sternotomy, a retractor was applied to open the chest minimally to access the mass. Minimal retraction helped to prevent any difficulty in breathing. The mass was successfully excised en-bloc and measured around 10 cm x 4 cm [Figure 2]. He had mild discomfort during handling of pericardium around arch of the aorta and during contact with the parietal pleura. He felt minimal pain from periosteum contact while doing hemostasis. As the level of anesthesia achieved was only till T8, local anesthetic was infiltrated to put mediastinal drain before the closure of sternum. The patient did not require any maintenance dose of epidural anesthesia intraoperatively. The patient was given mild sedation after the procedure with IV fentanyl 25 pg along with IV ondansetron 8 mg as antiemetic prophylaxis. The procedure was completed in less than an hour. A mixture of bupivacaine 0.0625% with fentanyl l2 pg/ml was administered at the rate of 2 ml/h in epidural infusion. Ringer lactate was used intraoperatively as maintenance fluid. The blood loss was estimated to be 200 ml and total urine output during procedure was 500 ml. Blood transfusion was not required. Arterial blood gas was within the normal limits. The patient was shifted to intensive care unit (ICU) for observation. Oral fluid was started 4 h after surgery. The patient was mobilized after removing the mediastinal drain and urinary catheter after 24 h. The epidural infusion was removed after 24 h as the patient had pain with VAS score of 3 on the next day of surgery. He remained hemodynamically stable throughout his ICU stay. The patient was discharged on the fourth postoperative day with advice of regular follow-up.