Empirical Pyridostigmine in a Patient with Difficult Weaning from Mechanical Ventilation after Traumatic Brain Injury

We present a 30-year-old male who sustained a mild traumatic brain injury and then was intubated due to deterioration of consciousness. A head CT scan revealed mild brain oedema, a fractured nasal bone and mild left thoracic wall haematoma. Despite complete clinical and radiological normalisation within 36 hours, he failed to wean off the ventilator. The patient was found to have subtle bulbar manifestations including dysphonia, dysarthria, and dysphagia, with recurrent left lung collapse. He responded to an empirical pyridostigmine trial despite negative biochemical tests for myasthenia gravis (MG). The patient was weaned successfully from the ventilator, transferred to a long-term care facility, and then discharged home. Classic symptoms and signs of a disease may be absent, but the presence of dysarthria, dysphagia, transient vocal cord palsy, nasal speech, absent gag reflex and respiratory failure in difficult-to-wean patients, with no definitive diagnosis, may warrant an empirical trial of therapy for suspected MG and for the benefit of any doubt.

"Hidden" cranial injuries may account for subtle bulbar symptoms in victims of traumatic brain injury and should be searched for.Myasthenia gravis has been reported in association with trauma, which comes first and is often difficult to ascertain.A trial of pyridostigmine may be reasonable in difficult-to-wean patients when all other causes have been excluded for the benefit of the doubt.