Recognition and management of phaeochromocytoma

Phaeochromocytomas and paragangliomas (PPGL) are catecholamine-secreting neuroendocrine tumours. These tumours may be identified incidentally, as part of a work-up for multiple endocrine neoplasia or following haemodynamic surges during unrelated procedures. Advances in preoperative management and improved management of intraoperative haemodynamic instability have significantly reduced surgical mortality from around 40% to less than 3%. Surgery is the definitive treatment in most cases and laparoscopic resection where possible is associated with improved outcomes. Anaesthetic management of PPGL cases represents a unique haemodynamic challenge both before, during and after tumour resection. In this article we describe the physiology of these tumours, their diagnosis, preoperative optimization methods, intraoperative anaesthetic management and management of postoperative complications.     

Recognition and management of phaeochromocytoma

Phaeochromocytomas are catecholamine-secreting neuroendocrine tumours arising from the chromaffin cells in the adrenal medulla. These tumours may be identified incidentally, as part of a workup for multiple endocrine neoplasia or during unrelated surgery. Better understanding of catecholamine physiology and advances in preoperative preparation has significantly reduced surgical mortality from around 40% to less than 3%. Surgery is the definitive treatment in most cases and laparoscopic resection is associated with reduced hospital stay and earlier mobilisation. Phaeochromocytomas are of particular interest to anaesthetists as it presents a unique haemodynamic challenge both before and after adrenal resection. In this article we describe the physiology of these tumours, their diagnosis and perioperative management.     

Recognition and management of phaeochromocytoma

Phaeochromocytoma is a rare catecholamine-secreting tumour with a high incidence of perioperative mortality if not managed appropriately. It benefits from an experienced structured medical, anaesthetic and surgical pathway. For anaesthetists successful and safe perioperative care requires knowledge of the pathophysiology of the condition combined with appropriate treatment strategies for preoperative preparation and management of acute release of catecholamines during periods of peri operative stress. Awareness of the perioperative presentation of phaeochromocytoma and associated signs and symptoms is important for all anaesthetists as the condition can present acutely during anaesthesia for other surgery. This has potentially a high mortality if not managed correctly.     

嗜铬细胞瘤/副神节瘤的围手术期处理

嗜铬细胞瘤/副神节瘤是由神经嵴起源的嗜铬细胞产生的肿瘤,具有分泌儿茶酚胺的功能,而儿茶酚胺作用于血管、心脏,常常引起血液循环系统及代谢的改变。嗜铬细胞瘤手术前后血液中儿茶酚胺浓度的变化会引起相应血液动力学的改变,若没有充分的术前准备和术后监护,心血管意外事件的发生几率很高。因此,了解嗜铬细胞瘤/副神节瘤的病理学特点,术前进行良好的药物准备,术中轻柔的手术操作及与麻醉师的良好配合,术后ICU的严密监护,是嗜铬细胞瘤围手术期处理的关键,也是嗜铬细胞瘤/副神节瘤成功治疗的基本保障。     

Outcomes of minimally invasive surgery for phaeochromocytoma

Laparoscopic adrenalectomy is now accepted as the procedure of choice for the resection of benign adrenocortical tumours, but few studies have assessed whether the outcomes of laparoscopic adrenalectomy for adrenal phaeochromocytoma are similar to that of other adrenal tumour types. This is a retrospective cohort study. Clinical and operative data were obtained from an adrenal tumour database and hospital records. A total of 191 patients had laparoscopic adrenalectomy, of which 36 were for phaeochromocytoma, over a 12‐year period. Length of hospital stay (4.8 vs 3.6 days, P= 0.03) and total operating times (183 vs 157 min, P= 0.01) were greater in the laparoscopic phaeochromocytoma resection group. Despite the greater size of the phaeochromocytomas compared to the remaining adrenal tumour types (44 mm vs 30 mm, P < 0.01), however, rate of conversion and morbidity were no different. Laparoscopic adrenalectomy for phaeochromocytoma is a safe procedure with similar outcomes to laparoscopic adrenalectomy for other adrenal tumour types.     

The perioperative management of children with phaeochromocytoma

The safe anaesthetic management of a child with a phaeochromocytoma requires an understanding of the pathophysiology of the disease, together with a thorough knowledge of its pharmacology, in order to avoid or minimize the potentially harmful cardiovascular changes that may occur during anaesthesia. Although there is a considerable amount of information on the management of the adult with phaeochromocytoma, much less has been written concerning children with the disease. Children differ significantly from adults in the incidence, location, presentation and management of this condition and these differences are discussed here together with some of the more controversial issues of management.     

Angiotensin II in the management of excision of phaeochromocytoma

The management of a patient with an unusual combination of anaesthetic problems, namely phaeochromocytoma and difficult intubation is described. Angiotensin II is discussed in the management of hypotension after excision of the tumour.     

Recognition and management of phaeochromocytoma

Phaeochromocytomas are potentially lethal catecholamine secreting tumours. Clinical presentation depends on the pattern of catecholamine secretion. The symptoms are diverse, but the most common are headache, diaphoresis and palpitations. These tumours represent a challenge to the anaesthetist because they can present unexpectedly perioperatively and the mortality is up to 50%. Diagnosis relies on the demonstration of excessive catecholamine production by 24-hour urine measurement. The tumour is usually localized by CT or MRI imaging. Excision of the tumour can be undertaken safely only when pharmacological control of the sympathetic nervous system and normovolaemia have been achieved. A number of antihypertensive agents have been used successfully in the perioperative period to maintain cardiovascular stability. Preoperative preparation should also include an assessment of myocardial function to exclude the presence of phaeochromocytoma-associated cardiomyopathy. Adrenalectomy can be performed using an open or laparoscopic approach, with each procedure having implications for the anaesthetist. Management of intraoperative hypertensive surges and arrhythmias requires an understanding of the physiology and pharmacology of phaeochromocytomas. This article details the clinical presentation, diagnosis and perioperative anaesthetic management of elective and emergency phaeochromocytomas.     

Recognition and management of phaeochromocytoma

Phaeochromocytomas are potentially lethal catecholamine secreting tumours. 90% occur in the adrenal glands (10% are bilateral) and 10% are extra adrenal. Clinical presentation depends on the pattern of catecholamine secretion. The symptoms are diverse, but the most common are headache, diaphoresis and palpitations. These tumours are important to the anaesthetist because they can present unexpectedly perioperatively and the mortality is up to 50%. Diagnosis relies on the demonstration of excessive catecholamine production by 24 hour urine measurement. The tumour is usually localized by CT or MRI imaging. Excision of the tumour can only be undertaken safely when pharmacological control of the sympathetic nervous system and normovolaemia have been achieved. A number of antihypertensive agents have been used successfully in the perioperative period to maintain cardiovascular stability. Preoperative preparation should also include an assessment of myocardial function to exclude the presence of phaeochromocytoma associated cardiomyopathy. Adrenalectomy can be performed using an open or laparoscopic approach, with each procedure having implications for the anaesthetist. Management of intraoperative hypertensive surges and arrhythmias requires an understanding of the physiology and pharmacology of phaeochromocytomas. This article details the clinical presentation, diagnosis and perioperative anaesthetic management of elective and emergency phaeochromocytomas.     

Alleviation of the peripheral hemodynamic effects of dexmedetomidine by the calcium channel blocker isradipine

Background: Alpha₂-adrenergic agonists have peripheral vaso-constrictive effects and central sympatholytic and sedative effects. Whereas the latter are the basis of their use in anesthesia, the former could limit their clinical application.
Methods: To study whether a vasodilator could alleviate the systemic and coronary vasoconstrictor effects of dexmedetomidine without influencing the central sympatholytic effects, the calcium channel blocker isradipine was infused after a high dose of dexmedetomidine in anesthetized dogs.
Results: Dexmedetomidine 10 μg. kg^-1 decreased plasma concentrations of norepinephrine and epinephrine by more than 90"/0, heart rate by 39%, cardiac output by 647%, dp/dt_max by 29% and increased mean arterial pressure by 55% and the left ventricular end-diastolic pressure (LVEDP) 4-fold as compared to baseline. In addition, coronary blood flow decreased by 52% and coronary venous oxygen saturation by 51%. Isradipine could completely antagonize all the coronary and systemic hernodynamic changes induced by dexmedetomidine, but only partially he increase in LVEDP. Isradipine caused no changes in plasma catecholamine levels.
Conclusion: Isradipine could alleviate the peripheral hemodynamic actions of dexmedetomidine while having no effect on its central sympatholytic properties.     

Nifedipine and surgical removal of phaeochromocytoma

The management of five patients with phaeochromocytoma undergoing surgical removal is described. Pre-operative preparation with phenoxybenzamine and nifedipine for 7 days before surgery prevented excessive fluctuations in cardiovascular parameters in the peri-operative period and resulted in an uneventful recovery.     

Effects of perioperative alpha1 block on haemodynamic control during laparoscopic surgery for phaeochromocytoma

Background. Laparoscopic surgery for phaeochromocytoma can causeexcessive catechol amine release with severe hypertension andsinus tachycardia. I.V. calcium antagonists may be used to preventincreases in blood pressure during phaeochromocytoma resection.We investigated the effects of perioperative     

Drugs affecting the heart: anti-hypertensives

It is common for patients presenting for surgery and requiring anaesthesia, and those unwell in intensive care, to be prescribed antihypertensive medication for the treatment of primary hypertension and other associated conditions. Antihypertensive drugs affect a range of targets including the renin-angiotensin system, Na⁺/water excretion, autonomic nervous system and direct vasodilatation. The physiology of hypertension, the pharmacology of antihypertensive agents and national treatment guidelines will be discussed in this article.     

Effects of a continuous diltiazem infusion on renal function during cardiac surgery

Thirty-five male patients undergoing coronary artery surgery were studied to investigate renal function during a continuous infusion of the calcium channel blocker diltiazem. All patients had preoperative renal function within normal limits (serum creatinine below 0.133 mmol/L) and were randomly divided into three groups: Control (C), Diltiazem 1 (D1), and Diltiazem 2 (D2). Diltiazem was infused in D1 (1 μg/kg/min) and D2 (2 μg/kg/min) patients throughout surgery and during the following 36 hours. Glomerular function was investigated using the endogenous creatinine clearance while tubular function was assessed by means of water and sodium reabsorption tests, as well as urinary enzyme activity measurements. Hemodynamic monitoring was performed using a pulmonary artery catheter. The glomerular filtration rate of C and D1 patients showed a significant fall during cardiopulmonary bypass (CPB) with respect to the prebypass period and returned to the baseline values only in the postoperative period. A similar change was not observed in D2 patients. The analysis of variance demonstrated that the glomerular filtration rate was significantly higher in Group D2 versus Group C during and after CPB (P = 0.03 and P = 0.04, respectively). Furthermore, after CPB, urinary output was significantly improved in D2 patients, both versus C and D1 patients (P = 0.003), notwithstanding a lower mean arterial pressure in the D2 Group (P = 0.04 v C Group). Tubular function was not influenced by diltiazem infusion. It is concluded that a continuous diltiazem infusion, at a dose of 2 μg/kg/min during cardiac surgery, may be useful to prevent a decrease in glomerular function secondary to cardiopulmonary bypass.     

Retroperitoneal paraganglioma: Single-institution experience and review of the literature

Paragangliomas are rare tumors arising from extra-adrenal chromaffin cells. We examined the clinical characteristics of all patients at our institution having paragangliomas resected from 1984 through 2005. Of 253 resections, 22 (9%) were retroperitoneal and were selected for further study. The ratio of males to females was 1.3:1, and the median age was 39 years. The average size, rate of metastasis (i.e., malignancy), and rate of function was 7.4 cm, 9.5%, and 57.1%, respectively. Tumors larger than 7 cm were more likely to require adjacent organ resection (P=0.01). The overall 5-year survival was 73%. Survival was significantly worse after metastasis (P=0.0023) but did not depend on the tumor diameter, the secreting function of the tumor, the status of surgical margins of resection, or status of the resected lymph nodes.     

Emergency resection of phaeochromocytoma presenting with hyperamylasaemia and pulmonary oedema after abdominal trauma

Phaeochromocytoma may present as an acute emergency with a perplexing variety of symptoms. We report a case in which a tumour of the organ of Zuckerkandl was removed after its unexpected discovery during laparotomy for abdominal trauma. A patient is described in whom a history of abdominal trauma coupled with collapse, pulmonary oedema, raised serum amylase and a positive peritoneal tap for blood, led to laparotomy at which an extramedullary phaeochromocytoma was found unexpectedly. The tumour was successfully resected, but immediate hypotension was life threatening. The inadvisability of resecting a phaeochromocytoma discovered at operation is discussed.