Cardiovascular autonomic dysfunction induced by mechanical insufflation-exsufflation in Guillain-Barré syndrome

Mechanical insufflation-exsufflation (MI-E) is an effective airway clearance device for impaired cough associated with respiratory muscle weakness caused by neuromuscular disease. Its complications on the respiratory system, such as pneumothorax, are well-recognized, but the association of the autonomic nervous system dysfunction with MI-E has never been reported. We herein describe two cases of Guillain-Barré syndrome with cardiovascular autonomic dysfunction during MI-E: a 22-year-old man who developed transient asystole and an 83-year-old man who presented with prominent fluctuation of blood pressure. These episodes occurred during the use of MI-E with abnormal cardiac autonomic testing, such as heart rate variability in both patients. While Guillain-Barré syndrome itself may cause cardiac autonomic dysfunction, MI-E possibly caused or enhanced the autonomic dysfunction by an alternation of thoracic cavity pressure. The possibility of MI-E-related cardiovascular complications should be recognized, and its appropriate monitoring and management are necessary, particularly when used for Guillain-Barré syndrome patients.