Abdominal Functional Electrical Stimulation to reduce respiratory complications in spinal cord injury

The abdominal muscles are the primary muscle group used during forced exhalation. We have shown that surface Functional Electrical Stimulation (FES) of the abdominal muscles, termed Abdominal FES, can improve respiratory function and assist weaning from mechanical ventilation in spinal cord injury. While respiratory function is directly linked to likelihood of respiratory complications in spinal cord injury, evidence that Abdominal FES reduces respiratory complications is anecdotal. We hypothesise that Abdominal FES will reduce the likelihood of respiratory complications in the acute (<6 weeks post injury) stage of spinal cord injury. Two hundred and forty participants will be recruited to this multi-site randomised, placebo controlled pilot trial. Participants with a new cervical spinal cord injury will be recruited 5-10 days post injury. 120 patients will be randomly allocated to receive Abdominal FES and 120 will receive a placebo. In the Abdominal FES group, Abdominal FES will be applied for 45 minutes per day, 5 days per week, for 5 weeks. Specifically, Abdominal FES will be delivered, via electrodes placed over the posterolateral surface of the abdomen. The stimulation amplitude will initially be set to 60 mA (50 Hz), which corresponds to 90% of the maximum amplitude that was tolerated by healthy volunteers in a previous study. If this amplitude results in discomfort to the patient (based on clinical judgement) then it will be reduced as necessary.Stimulation amplitude will be evaluated every 5 minutes to ensure that stimulation is still tolerable and causing a suitable muscle contraction. Stimulation will be applied by a local physiotherapist at each site.