Dexmedetomidine and magnesium sulphate as the anaesthetic adjuncts for intraoperative management for resection of pheochromocytoma - a case report

Abstract

Pheochromocytoma, a tumour arising from adrenal medulla or other ganglia of sympathetic nervous system is notorious for secreting catecholamines. This form of the tumour is a major challenge to anaesthesia team as acute changes in blood pressure and heart rate usually occurs due to the release of catecholamines from the tumour site before tumour resection and cessation of the same after resection leading to hemodynamic instability intraoperatively. Better hemodynamic stability is desired during this form of tumour resection as acute fluctuations in blood pressure may lead to severe intracranial or cardiovascular events. Dexmedetomidine and magnesium sulphate were used as anaesthetic adjuncts to achieve good hemodynamic stability in a 35 years old female who presented with the history of headaches, palpitation and sweating on and off since last 2 years. The use of these agents allowed us to obtain an acceptable level of hemodynamic stability along with the help of other agents such as inotropes, vasopressors, vasodilators and antihypertensive agents. Dexmedetomidine and magnesium sulphate were used before resection of the tumour in our case and stopped thereafter. These agents may be an excellent option as anaesthetic adjuncts to obtain greater hemodynamic stability during resection of pheochromocytoma.

Anaesthetic Management of a Labrador Retriever Undergoing Adrenalectomy for Phaeochromocytoma Excision, a Case Report

“…Dexmedetomidine, an α-2 receptor agonist, has been described in human medicine in combination with other drugs (e.g., MgSO 4 ) to achieve haemodynamic stability during phaeochromocytoma resection ( 1 , 28 – 30 ). The activation of α-2 receptors leads to a dose-dependent reduction in plasma catecholamines since they take part in the regulation of noradrenaline release through a negative feedback mechanism ( 31 ).…”

Perioperative use of thoracic epidural anaesthesia, dexmedetomidine and magnesium sulphate infusion in a dog undergoing neuroendocrine tumour resection

“…The combined use of epidural anaesthesia, DEX and MgSO 4 infusion has provided good intraoperative haemodynamic stability in human patients with PCC. [5][6][7] During surgical manipulation of a PCC, the activation of the sympathetic system following a catecholamine storm might be confused with nociception. 38 However, during nociception, both HR and arterial blood pressure, together with fR, generally increase.…”

“…In veterinary medicine, sodium nitroprusside, 20,35,36 phentolamine, 19,20,27,36 higher inspired fraction of isoflurane 35,37 and acepromazine 37 have been reported. The combined use of epidural anaesthesia, DEX and MgSO 4 infusion has provided good intraoperative haemodynamic stability in human patients with PCC 5–7 …”

“…By reducing the perioperative levels of stress‐related hormones, α 2 ‐adrenoceptor agonists attenuate the stress response in dogs 59,60 . Nevertheless, hypertensive crisis during PCC removal might not be fully prevented and other drugs (i.e., MgSO 4 ) might be needed in this event 6,7 …”

“…The unpredictable and uncontrolled noradrenaline secretion might result in hyper-or hypotensive crisis and haemodynamic collapse that is often unresponsive to conventional treatment. 4 The use of epidural anaesthesia in combination with dexmedetomidine (DEX) and magnesium sulphate (MgSO 4 ) infusion has provided good intraoperative haemodynamic stability in human patients with PCC, [5][6][7] but to our knowledge, it has never been reported in dogs.…”