A 25-year-old man is brought to the emergency department. The patient is in a confused state, his colleagues report that he was working at his desk and suddenly started having intense headache with profuse sweating. In the meantime, it is observed that the patient starts rolling his eyes. After some time, his wife arrives and she reports that such events had happened in the past and have been resolved spontaneously, but the patient had been reluctant to visit hospital as he had no medical insurance. He smokes 20 packs of cigarettes per year and drinks 2-3 beers on weekends. On clinical examination, he is confused and obeys simple commands. Deep tendon reflexes are intact, BP is 210/108 mm of Hg, and pulse is 124/min. Lab results are as follows: Na+ 142 meq/L K+ 3.8 meq/L BUN 30 mg/dL S creatinine 1.0 mg/dL Blood sugar 110 gm% According to the condition of the patient, what medication should be started before surgery?
Answer: d) Phenoxybenzamine and PropranololPHEOCHROMOCYTOMAPheochromocytomas & paragangliomas (extra-adrenal pheochromocytomas) are catecholamine- producing tumors derived from the sympathetic or parasympathetic nervous systemNeoplasms of chromaffin cellsClinical presentation is so variable, hence termed "the great masquerader"Episodes of palpitations, headaches, & profuse sweating are typical and constitute a classic triadClinical features listed by frequency of occurrence1. Headaches2. Profuse sweating3. Palpitations and tachycardia4. Hypertension (dominant sign) sustained or paroxysmal5. Anxiety and panic attacks6. Pallor7. Nausea8. Abdominal pain9. Weakness10. Weight loss11. Paradoxical response to antihypertensive drugs12 Polyuria and polydipsia13. Constipation14. Orthostatic hypotension15. Dilated cardiomyopathy16. Erythrocytosis17. Elevated blood sugar18. HypercalcemiaRule of 1010% bilateral10% familial10% malignant10% extraadrenal70% of extra-adrenal paragangliomas occur in head and neck region (organs of Zuckerkandl & carotid body)Biochemical testingCatecholamines synthesized and stored include - norepinephrine, epinephrine and dopamine.Predominant hormone from Adrenal pheochromocytoma -> NorepinephrinePredominant hormone from extra adrenal pheochromocytoma NorepinephrinePredominant hormone from Pheochromocytoma + MEN -> EpinephrinePlasma fractionated metanephrine - single most sensitive test24 hour urinary testsFractionated metanephrines - most sensitiveTotal metanephrines - most specificImagingAdrenal pheochromocytomaContrast CT and MRI - most sensitiveMIBG - most specificExtra-adrenal pheochromocytoma and paraganglioma - T2-weighted MRI with gadolinium contrastFNAC or NEEDLE BIOPSY & ANGIOGRAPHY - CONTRAINDICATED as it can trigger Bleeding or Hypertensive crisis.TreatmentSurgical removal of the tumor is the treatment of choice Preoperative preparationAlpha blocker therapy(phenoxybenzamine) should be given for atleast 7 days before surgeryLiberal salt intake and hydration - to avoid severe orthostasisBeta blockers (10 mg of propranolol three or four times per day) can then be addedMalignant pheochromocytomaPheochromocytoma with distant metastases are considered malignantThe first-line choice is nuclear medicine therapy for scintigraphically documented metastases, preferably with I-131-MIBG
Phentolamine and phenoxybenzamine
Propranolol
Nitroglycerine
Phenoxybenzamine and propranolol
Endocrinology