In resection of a large phaeochromocytoma with IVC invasion, haemodynamic instability especially with severe episodic hypertension from surgical stimuli and tumour manipulation are expected. Preoperative -blockade, intraoperative vasodilators and increasing anaesthetic depth are common measures to smoothen out the haemodynamic course and prevent hypertensive crises.3 Remifentanil is effective in blunting the sympathetic response to noxious stimuli and has been used in phaeochromocytoma excision to control intraoperative haemodynamic instability,4 but significant hypotension and bradycardia, and a large increase in plasma catecholamine levels and marked hypertension during manipulation have been reported.5 Dexmedetomidine, a highly selective
2-adrenoceptor agonist, has sedative and analgesic properties.6 It attenuates sympathoadrenal responses to tracheal intubation and surgical stimuli and has a significant anaesthetic-sparing effect when used intraoperatively.7 8 In order to blunt the intubation stress, we administered a high loading dose of dexmedetomidine of 2 mg kg1 before induction and the patient remained haemodynamically stable during intubation. After the loading dose, the infusion was maintained at 0.7 mg kg1 h1 until clamping of the IVC. In the remaining surgery, haemodynamic stability was maintained with inotropic support, which was stopped at the end of surgery.
In summary, we describe the management of a patient for excision of a large phaeochromocytoma with invasion into a major vessel, in whom dexmedetomidine was found a useful anaesthetic adjunct to maintain steady haemodynamics and to prevent abrupt hypertensive crises.
Hong Kong, China
References
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8 Aho M, Erkola O, Kallio A, et al. Dexmedetomidine infusion for maintenance of anesthesia in patients undergoing abdominal hysterectomy. Anesth Analg 1992; 75: 9406[Abstract]
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