CHEST Guidelines-A-Woman-in-Her-70s-With-a-History-of-Myasthenia-Gr (2)

A-Woman-in-Her-70s-With-a-History-of-Myasthenia-Gr (2)

Pdf Summary

This case involves a woman in her 70s with myasthenia gravis (MG) experiencing progressively worsening shortness of breath over three days. She presents with chronic diplopia, lower extremity weakness, but no slurred speech or dysphagia. Despite being anxious and having stable vital signs, her vital capacity (VC) and negative inspiratory force (NIF) were significantly low, prompting concern for impending respiratory failure. A chest radiograph revealed a small right pleural effusion.<br /><br />To determine the cause of her symptoms, a point-of-care ultrasound was used to evaluate the diaphragm's position and function. The ultrasound showed normal diaphragm excursion and thickening fraction, ruling out diaphragm dysfunction due to myasthenia crisis. Instead, the findings indicated pulmonary edema.<br /><br />The use of ultrasound in this case prevented unnecessary mechanical ventilation and treatment for myasthenia crisis, as it revealed the true cause of the patient's symptoms. The article highlights the utility of diaphragm ultrasonography as a reliable, non-invasive tool to guide treatment, especially in patients with suspected MG crises, where traditional methods like VC and NIF measurements might be unreliable due to patient effort or technique variables.<br /><br />Despite the initial suspicion of a myasthenia crisis due to the patient's history and symptoms, the ultrasound findings allowed clinicians to adapt the treatment plan, resulting in symptom improvement through diuresis instead. This underscores the value of dynamic ultrasound in assessing diaphragm function, which can provide objective information to guide therapy in patients with MG. The authors advocate for further research on the use of diaphragm ultrasonography in MG cases to enhance clinical decision-making.

Keywords

myasthenia gravis

shortness of breath

diaphragm ultrasound

respiratory failure

pulmonary edema

vital capacity

negative inspiratory force

diaphragm function

pleural effusion

clinical decision-making