Pheochromocytoma are tumours arising from neuroectodermal cells of the adrenal medulla or extra adrenal sites they are found increased frequency in patients with hypertension MEN2a and MEN2b syndrome and von recklimghausen,s nerurofibromatosis

Peak incidence

Is th 4 th and 5 the decade

The rule of tens applied to pheochromocytoma

as  10% are bilateral
  10%  extra adrenal
    10% familial
  10% multicentric
 10% malignant
Occurs in children 10%

The triad of headaches , papitations and diaphoresis should arouse the suspicion of a pheochromocytoma

Other significant symptoms include hypertension headache  postural hypotension and tremors


 Is confirmed by a 24 - hour urine collection for VMA  , metanephrine and catecholaminas with noradrenaline having the best sensitivity and VMA  the best specificity for pheochromocytoma  CT , MRI and  MIBG  are the imaging modalities used

CT  has been shown to have a sensitivity of 85-90%and a specificity of 70-100%

MIBG  is similar to noradrenaline in structure and hence taken up by adrenergic tissue .  MIBG  scanning provides useful functional data on these tumours


 Is by adrenalectomy which can be performed by a midline subcostal or transabdominal approach . alternatively laparoscopy may be used if the disease is benign

 Specific preoperative problems relating to surgery of pheochromocytomas

Include massive hypertensive surge during tumour handling . hypotensive shock following tumour devascularization and hypoglycaemia

A week,s preoperative treatment with long acting alpha blocker phenoxybenzamine combined with a beta blocker if tachycardia develops has reduced the operative mortality by controlling the catecholamine surge

 metyrosine (tyrosine hydroxlase antagonist ) is also occasionally used preoperative

general anaesthetic induction is using inhaled gases as isofurane to minimalize cardiac depressant effects
adequate volume repletion is necessary as often these patients are underfilled due to to the increased vasoconstrictive state

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