What is Orthostatic hypotension (postural hypotension)?
Orthostatic hypotension (postural hypotension) is a low blood pressure associated with weakness or fainting when one rises to an erect position (either supine to sitting, supine to standing, or sitting to standing).
It is the result of peripheral vasodilation without a compensatory rise in cardiac output. Patients most at risk for postural hypotension are older adults, patients who have been on prolonged bed rest, and those who are dehydrated or have sustained a significant blood loss. Some drugs, such as meperidine hydrochloride (Demerol) cause hypotension.
Arising and moving about slowly, especially after a period of bed rest, might prevent orthostatic hypotension. When ambulating the postoperative patient, the nurse should first raise the head of the bed, then assist the client to a sitting position on the side of bed (often called “dangling”) for a few minutes to assess for dizziness or faintness, and then assist to a standing position. If the patient becomes dizzy or feels faint, he or she should be returned to bed and placed in a supine position, which restores blood flow to the brain.