Background:
Maximal inspiratory pressure (MIP) is used to assess respiratory muscle strength of patients with myasthenia gravis (MG) requiring ventilatory support. Electrical activity of the diaphragm (E-di) has been used to guide weaning.
Case presentation:
The MIP and tidal volume/ΔE-di (the patient-to-ventilator breath contribution) were monitored in a 12-year-old girl with MG requiring ventilator support. The same ventilatory settings were maintained until extubation. During weaning, MIP increased slightly, but varied unpredictably. Tidal volume/ΔE-di decreased at a constant rate as muscle strength recovered.
Conclusion:
In this patient with muscle weakness, E-di was a reliable tool to monitor weaning from mechanical ventilation.