Surface functional electrical stimulation of the abdominal muscles to enhance cough and assist tracheostomy decannulation after high-level spinal cord injury

Abstract

Objective: Evaluation of noninvasive stimulation modalities to augment cough and assist tracheostomy decannulation in high-level tetraplegia.

Study design: Single case study.

Methods: A 65-year-old man with C4 ASIA C tetraplegia had delayed rehabilitation due to a tracheostomy and recurrent pneumonia primarily resulting from ineffective cough. Anterior surface electrical stimulation (SES) of the abdominal musculature was conducted to train an effective cough and enable decannulation. Training occurred daily for 4 weeks. The patient was tested 1 year later with posterolateral SES to determine the relative clinical effect of this delivery method.

Results: At baseline, the addition of anterior SES increased maximal expiratory pressure (80%), maximal expiratory cough pressure (67%), and peak expiratory flow rate (11%). Three weeks after training began, the patient was decannulated following a program of SES and assisted and voluntary coughing. Upon testing 1 year later, SES with posterolaterally placed electrodes also produced an enhancement of voluntary cough attempts.

Conclusions: Noninvasive SES can potentially assist decannulation of tracheostomies.

Figures

Figure 1. (A) Anterior electrode placement (ward testing); (B) Baseline and posttraining results for maximal expiratory pressure (MEP); (C) Maximal expiratory cough pressure (MECP); and (D) Peak expiratory flow rate (PEFR). Responses without stimulation (open bars) and with stimulation (filled bars) are shown.

Figure 2. (A) Posterolateral electrode placement (laboratory testing); (B) Typical flow, volume, gastric pressure (Pga) and esophageal pressure (Pes) during a voluntary cough without (left panels) and with (right panels) posterolateral surface electrical stimulation (SES). Timing of stimulation is indicated by the thick horizontal bar.