Postural Hypotension and Orthostatic Hypotension
Hypotension: What is it?
If you have hypotension it means that you have low blood pressure. Postural hypotension and orthostatic hypotension mean the same thing. When your blood pressure drops because of a change in your position, a temporary decrease in blood flow to your brain occurs. This may cause you to have a light- headed or faint feeling. You may feel dizzy or nauseated. You may also look pale and have numbness around your face.
Why Does it Happen?
Postural hypotension happens more often when you are first injured, tired or after an illness. Low blood pressure is common in people with spinal cord injury, especially if the level of injury is at T-6 or above. Because of a change in the autonomic nervous system, the blood vessels do not adjust in size to make up for sudden blood pressure shifts like they normally would. This can also cause blood to pool in the legs, feet and ankles while you are sitting or standing.
When Does it Happen?
Postural hypotension usually happens when you go from lying down to being upright, such as when you transfer into your wheelchair or the standing frame. You will need to get use to being up again if you have been on bed rest for a long time. Other situations that can affect blood pressure include eating large meals, not drinking enough water, drinking alcohol, exercise, infection, time of day, and a hot environment.
What Helps to Prevent it?
It is helpful to come to a sitting or standing position gradually. You should try not to make quick position changes. You can slowly get used to being upright by raising your head in the bed with pillows before doing your transfer.
Eating smaller meals more often throughout the day instead of large meals at one sitting will help keep your blood pressure more even. Drinking plenty of water throughout the day supports your blood volume. You should try not to become overheated because dehydration lowers blood pressure.
Another thing that may happen with low blood pressure is a decrease in the amount of urine produced by the kidneys when you are upright. You may notice that there is less urine in your leg bag while you are sitting up but after you lie down your leg bag fills up quickly. This is because of the increase in blood pressure that happens when you lie down that allows fluids to be released from the lower legs and feet. It is important to watch your drainage bag closely after lying down and make sure it gets emptied before it gets too full.
What to Do if it Happens:
If postural hypotension occurs while you are in a wheelchair, you can be tilted backwards until your head and neck are nearly horizontal to the floor. Raising your legs above the level of your heart increases the blood flow to your brain. The light-headed feeling will quickly disappear. You can gradually return to a sitting position once you are feeling better. Wearing an abdominal binder and elastic TED hose or compression stockings on your legs is also helpful.
Talk to your doctor right away if you have any of the symptoms of postural hypotension or low pressure. Feeling lightheaded, dizzy, nauseated, numb around your face, and looking pale are signs that your blood pressure has dropped. Your doctor will want to know what triggers these symptoms and what makes them go away. Your doctor might also talk to you about medications that you can take before getting up that may help keep your blood pressure more level. As always, it is never a good idea to take anything that your doctor has not OK’d.