Don't forget about pheochromocytoma as a possible cause of severe hypertension...especially in those patients that are recalcitrant to "normal" medications. A few important points: 1. Incidence may be as high as 0.2% of patients with hypertension...sounds very rare, but statistically we'll all see some during our career. 2. Mortality may be as high as 10% if unrecognized; but if recognized and treated, excellent prognosis. 3. Suspect this in patients with intermittent episodes of flushing, palpitations, diaphoresis, headaches, and hypertension. 4. Treatment with beta blockers alone (including labetalol) may induce unopposed alpha-activity and worsen BP. 5. Treat with nitroprusside or phentolamine (an alpha blocker). Phentolamine is 5 mg IV, can be repeated every 5-10min as needed. 6. After phentolamine is given, there may be reflex tachycardia. NOW you can add beta blockers.
The most important thing is to keep the diagnosis in mind. It's out there! But you'll miss 100% of the diagnoses you don't consider.
