Combined intercostal and diaphragm pacing to provide artificial ventilation in patients with tetraplegia.

Abstract

To evaluate the usefulness of combined intercostal and diaphragm pacing to maintain independence from mechanical ventilation. A prospective trial. Clinical research center at a large tertiary hospital. Four ventilator-dependent subjects with spinal cord injury with only unilateral phrenic nerve function. During an initial surgical procedure, a multipolar epidural disk electrode was positioned on the ventral surface of the upper-thoracic spinal cord via a hemilaminectomy to activate the inspiratory intercostal muscles. A phrenic nerve electrode was implanted unilaterally via the thoracic approach. Inspired volume production and duration that subjects could be comfortably maintained when off mechanical ventilatory support. Initial maximum inspired volumes from combined intercostal and diaphragm stimulation ranged between .23 and .93L and significantly increased over the course of reconditioning period to between 0.55 and 1.31L; subjects could be maintained off mechanical ventilation between 16 and 24 hours a day. Combined intercostal and unilateral diaphragm pacing may be a useful therapeutic modality capable of maintaining long-term ventilatory support in patients with only unilateral phrenic nerve function.