The Effect of Midodrine on Exercise-induced Hypotension in Cervical Cord Injury Patients

ABSTRACT

OBJECTIVE: To evaluate the effect of midodrine, an alpha(1) agonist, on symptom and hemodynamic response during standing and arm bicycle ergometer exercise in patients with cervical cord injury. METHOD: Twelve cervical spinal cord injury patients with orthostatic hypotension symptoms and post-exercise hypo- tension were enrolled. They were positioned on a 90degrees standing frame for 3 minutes. After 15 minutes of resting on supine position, 5 minutes of arm bicycle ergometer exercise was done. These tests were done without midodrine initially, but, with 5 mg midodrine on the next day. Heart rate, self-perceived presyncope score (PPS), systolic and diastolic blood pressure were measured before, during and after the exercise. RESULTS: With 5 mg midodrine, the decrease of systolic and diastolic blood pressures after 3 minutes' standing was significantly smaller than without midodrine (p<0.05). PPS was also significantly decreased with midodrine on standing frame test. Arm ergometer exercise induced less systolic blood pressure decrease and better PPS on immediate and 5 minutes after exercise with midodrine (p<0.05). The change of diastolic blood pressure and heart rate was not significant after the exercise with midodrine. CONCLUSION: In cervical spinal cord injury patients with orthostatic and post-exercise hypotension, 5 mg midodrine significantly improved the symptoms and the systolic blood pressures.