Cardiovascular Physiology

Hypertension of Unknown Origin
(ver. 5/8/06)

I. Initial Setup

Call up patient #29 in web-HUMAN.

Run the patient for 0 min. with 0 min. between printouts.

Call up the person's chart ("Patient Charts....").

II. Characterization of the condition

To characterize this woman as

- hypertensive

- tachycardic

- hyperventilating

- hypermetabolic

- sweating

- showing too much sympathetic NS activity

run the model for very brief periods (0-5 min. maximum), resetting up your View Output: Tables between runs to characterize/ demonstrate each of the above.

III. Treatment / Management , part I

Examine the PHARMACY ("Patient Charts....") for pharmaceuticals that might be utilized to bring this hypertension under control.

   Chlorothiazide  (Continuous - to 1000 Mg/Day) , a diuretic , blocks Na+ reabsorption

   Converting Enzyme Inhibitor  (Continuous - to 600 Mg/Day) , e.g. Captopril

   Furosemide  (One Time - to 100 Mg)- diuretic , blocks ascending limb Cl- reabsorption.

   Hydralazine  (Continuous - to 75 Mg/Day) - a non-specific vasodilator

   Nitroglycerin  (As Needed - to 1 Mg) - is a non-specific vasodilator.

   Phenoxybenzamine  (Continuous - to 75 Mg/Day) , an alpha blocker

Try various pharmacologic treatment strategies to bring the pressure under control. For each drug, estimate its possible suitability by examining the state of the system it works on. For example, CEIs work largely by interfering with aldosterone driven Na+ reabsorption. Is there any evidence for elevated plasma Na? For raised plasma rennin-angiotensin activity?

Do not read the section below here until you have completed your drug treatment trials!

<------- no peeking! -------->

IV. Treatment / Management , part II

The physiologic profile developed in the Characterization section above is part of a characteristic physiologic profile for pheochromocytoma. You should be able to explain how the condition causes each of the pieces of that profile.

Show that the patient is responsive to an alpha blockade at a level of about 30 mg/day by

- initiating dosing

- running for 12 hours (12 H) w/ one hour between printouts.

VI. Extra credit: Characterize and explain the response to Hydralazine.

Special thanks to my students Amanda Getty '04, Kristen Near '04 and Maxwell Ruby '05 for their help in piloting this case.