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Updated: Aug 4, 2026

Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance
Published on: March 21, 2013
Idiopathic orthostatic hypotension, midodrine, and anaesthesia
1Department of Anesthesiology, University of British Columbia, Vancouver.
Abstract:
A patient with idiopathic orthostatic hypotension receiving chronic oral midodrine therapy required anaesthesia for coronary artery bypass grafting. A perioperative infusion of phenylephrine was substituted for midodrine, an alpha-2 agonist, enabling hypotension resulting from low systemic vascular resistance to be controlled easily. Anticipated adrenergic receptor denervation hypersensitivity was noted. The only significant perioperative problem was one episode of syncope from orthostatic hypotension during the reambulation period.
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