A 22-Year-Old Woman Is Brought to the Emergency Department by Her

question 193

Multiple Choice

A 22-year-old woman is brought to the emergency department by her boyfriend after an episode of syncope.  The patient says she feels "fine" and wants to go home.  She has no prior medical conditions and takes no medications.  Her boyfriend states that she is in good health and that she exercises every day, sometimes even "too much" because she wants to be in great shape.  The patient has smoked a pack of cigarettes daily for 2 years but does not use alcohol.  She smokes marijuana at least twice a week.
Temperature is 36.7 C (98 F) , blood pressure is 100/70 mm Hg, pulse is 114/min, and respirations are 16/min.  BMI is 17 kg/m².  Physical examination shows dry mucous membranes and normal jugular venous pressure with no thyromegaly.  The lungs are clear on auscultation and heart sounds are normal.  The abdomen is soft and nontender.  Neurologic examination is within normal limits.
Laboratory results are as follows:
Urine pregnancy test results are negative.  In the emergency department, 50% dextrose is administered and normal saline infusion is begun.  Two hours later, the patient experiences sudden-onset double vision.  On repeat examination, she appears mildly lethargic and there is lateral gaze palsy on the right side.
Which of the following is the most likely cause of this patient's vision disturbance?

• A)Magnesium deficiency
• B)Marijuana toxicity
• C)Refeeding syndrome
• D)Starvation ketoacidosis
• E)Vitamin deficiency

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Definitions:

Self-serving Bias

The tendency to attribute positive events to one's own character but attribute negative events to external factors.

Teachers

Professionals who help students acquire knowledge, competence, or virtue in educational settings.

Teaching Ability

The capacity or skill of an individual to impart knowledge or skill to others effectively.

Internal Characteristics

Qualities or features that are inherent or intrinsic to something or someone.