Anaesthetic management for laparoscopic bilateral adrenalectomy in MEN2A (Multiple endocrine neoplasia) followed by subsequent total thyroidectomy and radical neck dissection

Abstract

Editor—We report a case of MEN2A syndrome who underwent bilateral laparoscopic adrenalectomy and staggered total thyroidectomy and radical neck dissection with intraoperative nerve monitoring. Multiple Endocrine Neoplasia (MEN) is a syndrome which involves more than one endocrine gland. There are 3 types and further subtypes of MEN. MEN2A is characterized by medullary thyroid cancer (97%) with phaeochromocytoma (50%) and hyperparathyroidism (20%). 2 A 25-year old female suffered from bilateral goitre later diagnosed as bilateral medullary thyroid carcinoma. No tracheal compression was seen on CT, and metanephrines and normetanephrines weremarkedly elevated without demonstrable hypertension. CT scan of adrenals revealed 1 cm right nodule and 5.8 cm left nodule. A diagnosis of MEN2A was made supported by genetic test. Blood pressure and electrocardiogram (ECG) were normal. The patient received propranolol 20 mg and prazosin 2mg daily for 2 weeks, later increased to 6mg daily in divided doses 2 days before surgery for adequate alpha blockade. Monitoring included ECG, invasive blood pressure, pulse oximeter, central venous pressure and a bispectral index (BIS) monitor. Vasoactive drugs were made readily available. Anaesthesia was induced with propofol 2 mg kg, fentanyl 5 mcg kg and rocuronium 40 mg. She was intubated uneventfully and mechanical ventilation commenced at tidal volumes 5ml kg. Anaesthesia wasmaintained with an oxygen/air mixture and using Target Controlled Infusions (TCI) of remifentanil (4 ng ml effect mode) and propofol (3mcg ml, Schenider regimen). During right adrenalectomy, there were several surges in blood pressure as well as bradycardia which usually observed during adrenalectomy for phaeochromocytoma. Frequent adjustment of propofol (4mcg ml), remifentanil (5 ng ml) and sodium nitroprusside (SNP) (3mcg kg min) were required. Once blood supply to adrenal gland was severed, haemodynamic parameters were normal. However, during left adrenalectomy and manipulation of the large tumour, changes in blood pressure were much more pronounced requiring much higher doses TCI drugs and SNP and the control in blood pressure was inadequate. Intravenous phentolamine 1 mg bolus was administered resulting in immediate desired response but led to persistent tachycardia which was treated with 5 mg labetalol. Once left adrenalectomy was completed, there were no more haemodynamic changes. After adequate analgesia and successful extubation, patient was transferred to high dependency unit and then to a general ward and later discharged home after 5 days. Six weeks later, she was scheduled for total thyroidectomy and radical neck dissection with intraoperative nerve monitoring. Haemodynamic parameters were within normal limits. After loading dose of hydrocortisone 200 mg and routine monitoring, anaesthesia was induced with propofol 2 mg kg and fentanyl 1.5 mcg kg and rocuronium 0.5 mg kg. The trachea was intubated with an oral nerve integrity monitor (NIM) Flex EMG oral endotracheal tube (Medtronic Xomed, Inc, Jacksonville, USA) to monitor intraoperative recurrent laryngeal nerve function. Anaesthesia was maintained with TCI with remifentanil (2–4 ng ml effect mode) and propofol (2–3mcgml Schenider regimen) and BIS values were kept between 40 and 60 and no further muscle relaxant was administered. The patient remained stable throughout the surgery lasting 14 h. After extubation, she was transferred to a High Dependency Unit and discharged home after one day. The patient remained well for the two more surgical follow ups and remains well under the care of an endocrinologist. We had no previous experience of managing MEN2A patient and the literature search did not offer any meaningful practical advice. 6 We managed this case based on our experience of managing routine adrenalectomy for phaeochromocytoma.