Midazolam-sufentanil anaesthesia for phaeochromocytoma resection

Implications and considerations during pheochromocytoma resection: A challenge to the anesthesiologist

Pheochromocytoma is a rare catecholamine secreting tumor arising commonly from adrenal medulla. It has got multidimensional challenging aspects in spite of our improved understanding of its physiological and clinical behavior during surgical resection. This neuroendocrine tumor is associated with a most unpredictable and fluctuating clinical course during anesthesia and surgical intervention. The clinical difficulties and challenges increase manifold in patients with undiagnosed or accidental diagnosis of pheochromocytoma who present to the hospital for the treatment of some other disease or emergency. The most common manifestations of this clinical spectrum include hypertension, headache, palpitations, episodic sweating, and feeling of doom. The definite and only treatment for this rare tumor is surgical resection which itself is very challenging for an anesthesiologist. This article reviews the pre-operative evaluation, pharmacological preparation, intraoperative and post-operative management of patients with pheochromocytoma especially from anesthesiologist's perspectives.

The use of remifentanil in the anaesthetic management of patients undergoing adrenalectomy: a report of three cases

The use of remifentanil has been recommended because of its ability to minimise the hypertensive response to tracheal intubation and surgical stimulation in various types of surgery. We describe the use of remifentanil in the anaesthetic management of three cases of open adrenalectomy, two for removal of a phaeochromocytoma and one for removal of an adrenal cortical tumour. Although the use of remifentanil was associated with no adverse events in the patient undergoing resection of the adrenal cortical tumour, its administration was associated with significant hypotension and bradycardia in the two phaeochromocytoma patients, who had both been given alpha- and beta-adrenergic receptor blocking drugs before surgery. It did not prevent the increases in blood pressure or plasma catecholamine levels associated with tumour manipulation in these patients. Remifentanil should therefore be used with caution in patients receiving alpha- and beta-adrenergic receptor blocking drugs. The use of potent vasodilators may still be necessary during tumour manipulation even if remifentanil is being infused.

Pharmacokinetics of sufentanil in general surgical patients under different conditions of anaesthesia

The pharmacokinetics of sufentanil were studied in 56 surgical patients after an intravenous bolus of 2 micrograms kg-1, in association with neurolept analgesia or volatile anaesthetics (halothane, enflurane and isoflurane). Plasma concentrations of sufentanil were measured by radioimmunoassay. The kinetics of sufentanil were comparable under neurolept analgesia and under anaesthesia with halothane, enflurane or isoflurane. The overall mean elimination half-life was 182 min, Vdss 169 l and the plasma clearance 910 ml min-1. Except for the isoflurane subgroup, there was no significant correlation between half-life, the volume of distribution or clearance with age (24-77 years) or body weight (45-95 kg).

Propofol-fentanyl anesthesia for pheochromocytoma resection

Numerous anesthetic techniques and agents have been used for anesthetizing pheochromocytoma patients. However, a comparison based on literature reports is difficult, since most describe only isolated cases. We discuss current anesthetic techniques and a case report of a patient who successfully received a combined propofol-fentanyl anesthesia for pheochromocytoma resection.

Sufentanil-midazolam anesthesia for coronary artery surgery

The combination of benzodiazepines and high-dose narcotics has been reported to produce hypotension in patients undergoing coronary artery surgery. This study was performed to evaluate the cardiovascular effects of lower doses of the narcotic sufentanil administered with the benzodiazepine midazolam. Thirty adult patients with good ventricular function undergoing elective coronary revascularization received sufentanil, 2.5 micrograms/kg, and midazolam, 0.1 mg/kg, followed by infusions of sufentanil, 0.7 to 1.5 micrograms/kg/h, and midazolam, 0.07 to 0.15 mg/kg/h. Overall, stable hemodynamics were achieved before and after cardiopulmonary bypass (CPB). Patients who were not receiving preoperative beta-adrenergic blockade (n = 15) had increases from baseline heart rate and rate-pressure product after sternotomy, during aortic dissection, and after CPB that were not clinically significant. Five patients developed hypertension (increases greater than 20% over the baseline value), which was controlled with additional sufentanil or a vasodilator. Hypertension requiring vasodilator therapy did not occur in patients taking beta-adrenergic blockers. Blood pressure decreases exceeding 20% of the baseline value did not occur. Two of 15 patients receiving beta-blockers, versus 3 of 15 not receiving beta-blockers, developed ischemic electrocardiographic changes before CPB (NS); one of these patients without beta-blockade had a postoperative myocardial infarction. The results of this study show that the infusion of low doses of sufentanil with midazolam provides a hemodynamically safe and stable anesthetic for coronary artery surgery and avoids the hypotension seen when a high-dose narcotic is combined with a benzodiazepine.