Nonpharmacological approaches are extremely important (Table 3). Patient Education
Patient education is extremely important. The patient should understand in simple terms the maintenance of postural normotension. They need to understand the orthostatic stressors and their mechanisms. Important items of education include the following.
1. Advice on handling early morning and postprandial worsening of OH.
2. Instructions on how to keep a BP log. The patient or caregiver should learn to use an automated sphygmomanometer to measure BP with the patient supine and after standing for 1 minute. It is helpful to the physician if, for 2 or 3 days before a visit, recordings have been taken and recorded on awakening, after a meal, during a time of maximal orthostatic tolerance, during a time of poor orthostatic tolerance, and before and 1 hour after medication.
3. Salt and volume expansion. All patients with neurogenic OH require generous fluid intake of five to eight 8-ounce glasses of fluid each day. Salt supplementation is essential. Most patients manage with added salt with their meals. Occasionally, patients prefer to use salt tablets (available as 0.5 g tablets). Adequate salt and fluid intake can be verified by checking the 24-hour urinary volume and concentration of sodium. Patients who have a value less than 170 mmol/24 hours can be given supplemental sodium, 1-2 g three times daily (39). Their weight, symptoms, and urinary concentration of sodium should be checked 1 or 2 weeks later.
4. Oral water bolus. The imbibing of a moderate volume of water results in a reduction in OH that lasts for about 2 hours. In a recent study, rapid water drinking (480 mL) increased BP by a mean of over 30 mmHg in patients with multiple system atrophy and pure autonomic failure (40). The pressor response was evident within 5 minutes after drinking started, reached a maximum after 30-35 minutes, and was sustained for 1-2 hours. The practical application of this observation is that the patient who needs to be subjected to sustained orthostatic stress should drink two 8-ounce glasses of water 10-20 minutes before such activity.
5. Raise head of bed. The head of the bed is elevated four inches for two reasons. First, it reduces nocturia, probably by stimulating renin release. Second, it reduces supine hypertension. During the day, it is important to maintain adequate orthostatic stress. If patients are tilted up repeatedly, OH gradually attenuates. This likely result from the release of renin and arginine vasopressin, which requires more sustained or repetitive orthostatic stress. Another mechanism that has been suggested is extravasated plasma around veins providing a vascular cuff, increasing venomotor tone.
6. Compression garments. For some patients, wearing a tightly fitting body stocking ameliorates OH and associated symptoms. These stockings have to be well-fitted and put on before arising. They work by reducing the venous capacitance bed. Their disadvantages are the cumbersome application and discomfort in hot weather. Calf compression alone confers minimal benefit, but a reasonable substitute to Jobst compression is the use of a tightly fitting abdominal binder, which confers about two-thirds of the benefit (41).
7. Physical countermaneuvers. Physical counter-maneuvers that involve the contraction of certain muscle groups of the lower extremities decrease venous capacitance and increase venous return (42). These maneuvers, which once learned can substantially prolong standing time, include crossing of the legs and contracting the leg muscles of one leg against the other, slow stepping or marching on the spot, propping the leg up on a chair, or contraction of the thigh muscles (43).
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Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...