A 68-Year-Old Man with Myasthenia Gravis Is Evaluated for Progressive

question 1177

Multiple Choice

A 68-year-old man with myasthenia gravis is evaluated for progressive weakness while hospitalized.  The patient was admitted 2 days prior due to fever, productive cough, and pleuritic chest pain.  Chest x-ray demonstrated a right lower lobe consolidation for which the patient has been receiving intravenous ceftriaxone and azithromycin.  He also has been receiving his outpatient dose of pyridostigmine.  In the past several hours, he has experienced progressive generalized weakness and an inability to cough out sputum.  His temperature is 37.6 C (99.8 F) , blood pressure is 130/70 mm Hg, pulse is 110/min, and respiratory rate is 25/min.  Oxygen saturation is 89% on 4 L/min oxygen by nasal cannula.  The patient appears to be in distress, and his breathing pattern is rapid and shallow with occasional gurgling sounds.  Lung auscultation reveals coarse crackles throughout.  There is mild weakness of the extremities, but deep tendon reflexes are normal.  His vital capacity is now 1.0 L compared to 1.5 L at the time of admission, and arterial blood gas shows pH 7.27, pCO₂ 55 mm Hg, and pO₂ 60 mm Hg.  The patient is intubated and moved to the intensive care unit.  Which of the following is the best next step in management of this patient?

• A)Close observation only
• B)Increase pyridostigmine dose
• C)Intravenous atropine
• D)Therapeutic plasma exchange
• E)Thymectomy

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Definitions:

Postoperative Urine Output

The amount of urine produced and expelled by a patient after undergoing surgical procedures, an important indicator of renal function and fluid balance.

Bowel Resection

A surgical procedure where a part of the intestine is removed due to conditions such as cancer, blockages, or inflammatory diseases.

Specific Gravity

A measure of the density of a substance compared to the density of water.

Dehydration

A condition resulting from the excessive loss of body water.