Spinal Cord Injury Secondary Condition Orthostatic Hypotension
Orthostatic hypotension was described earlier. Please see that section for an explanation of what this condition is and why it occurs after spinal cord injury.
This condition is usually present to some degree during the initial stages of inpatient rehabilitation. Healthcare professionals taking care of spinal cord injured patients are aware of this condition and make every effort to limit its effect on the rehabilitation process.
If the management of orthostatic hypotension was started in the intensive care unit then these measures are usually continued. This includes an abdominal binder and elastic stockings to prevent excessive blood from pooling in the lower extremities. Blood rapidly pooling in the lower extremities can cause a decrease in blood perfusion (flow) to the brain which may lead to dizziness or fainting. In addition, the continued attempts to put the patient in a more upright position will continue with sitting on the edge of the bed for prolonged periods of time with support or a padded tilt-table if needed. Blood pressure must be intermittently monitored and the patient should be watched closely for any signs or symptoms of dizziness or fainting. If this does occur the patient is immediately lowered from the upright position to a more flat (lying down) position and/or the legs can be elevated above the heart. This technique usually results in reversal of symptoms within seconds to minutes. During the rehabilitation process, the patient may be upright or even sitting for several minutes or more when the symptom of dizziness starts. In this situation the patient should be tilted backwards in the wheelchair with assistance or reclined in a power wheelchair until the symptoms have resolved.
Most of the above compensatory techniques are performed while waiting for the patient to emerge out of spinal shock. As the patient comes out of a spinal shock he begins to develop more appropriate blood vessel contraction in the upright position, eventually eliminating the need for the abdominal binder or elastic stockings.
In some cases all of the above interventions are unable to prevent dizziness and fainting related to orthostatic hypotension and this interferes with the rehabilitation process. In these situations it is common for the attending physician to prescribe medications to aid in maintaining an appropriate blood pressure and preventing a rapid drop. Salt tablets are often used initially if there are no medical reasons why this should not be used. Fludrocortisone (Florinef) is a steroid that encourages salt retention. Both salt tablets and fludrocortisone helped to maintain blood pressure by causing the body to hold onto water in the bloodstream which helps to “keep the tank full of fluid.”
Another frequently used medication is midodrine hydrochloride. It causes a contraction of the blood vessel, which helps to prevent it from expanding and pooling with blood. All of these medications need to be used carefully or avoided in individuals who have any heart problems such as congestive heart failure. These medications also have a tendency to raise blood pressure when the patient is lying flat and therefore blood pressure should be evaluated in this position. Electrolytes such as sodium, potassium, and chloride also need to be periodically monitored. Individuals who have experienced Autonomic Dysreflexia (described below) should also be evaluated for an increase in blood pressure.
Orthostatic hypotension usually begins to resolve during rehabilitation as the patient emerges from spinal shock and with the appropriate use of the above techniques and medications. Once the blood pressure has remained stable for several days, the above techniques and medications can be gradually withdrawn.
