Philippines Cabahug, MD
Assistant Professor
Kennedy Krieger Institute; Johns Hopkins SOM
Baltimore, Maryland, United States
12-year-old male with C3-C6 spinal cord infarct, bilateral diaphragm paralysis with chronic respiratory failure with ventilator dependence. Diaphragm ultrasound (DUS) study done 2 months after SCI showed bilateral hemidiaphragm atrophy and paralysis. EMG-NCV study done 3 months after SCI showed C3-C7 acute denervating disorder, mild right and complete left phrenic neuropathy, and intact left T7-T12 intercostal nerves. Follow-up DUS showed further progression of atrophy. Electrodiagnostics at 6 months showed complete left phrenic neuropathy, normal right phrenic nerve motor nerve conduction. Right phrenic nerve stimulator implantation, left intercostal to phrenic nerve transfer with phrenic nerve stimulator placement was done at 7 months. 3 months later, the right phrenic nerve pacer was activated. DUS confirmed adequate pacing of right diaphragm. Vent waning was initiated. Patient used the vent only at night. 9 months post-surgery, left pacer was activated. DUS confirmed left diaphragm contractility. Clinically, patient reported improved comfort with both pacers on.
Discussions:
This patient presented with right upper motor neuron and left lower motor neuron pathology of his diaphragm. Right phrenic nerve stimulation facilitated daytime weaning off ventilation. Patient reported improvement in comfort and ease in breathing was reported on activation of the left pacer.
Conclusions: Phrenic nerve stimulation combined with stimulation of Intercostal to phrenic nerve transfer can be done safely to wean high cervical SCI patients from long term mechanical ventilation. DUS can enhance pre-operative assessment and monitoring during pacer adjustment.
