A 4-Year-Old Boy Is Being Evaluated for Failure to Thrive

question 14

Multiple Choice

A 4-year-old boy is being evaluated for failure to thrive, shortness of breath, and exercise intolerance.  The parents first became aware of his symptoms after the patient started preschool a few weeks ago.  His teacher mentioned that the patient seemed to tire faster than the other children when playing outside.  Cardiac examination shows bounding peripheral pulses and a palpable thrill below the clavicle near the left upper sternal border.  On auscultation, a continuous murmur is best heard over the same region.  After discussion with the parents, a thoracotomy is scheduled to correct the patient's condition.  During the procedure, the surgeon should plan on ligating a derivative of which of the following embryologic structures?

• A)Bulbus cordis
• B)Fourth aortic arch
• C)Primitive atria
• D)Sinus venosus
• E)Sixth aortic arch

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Definitions:

Standard Deviation

A gauge for determining the level of difference or scattering in a series of amounts.

Mean High Temperature

The average of the highest temperatures observed over a specified period.

Normal Distribution

A symmetric, bell-shaped distribution of values in which the mean, median, and mode are all equal and located at the center of the distribution.

Standard Deviation

Standard deviation is a measure of the amount of variation or dispersion of a set of values; a low standard deviation indicates that the values tend to be close to the mean, while a high standard deviation indicates that the values are spread out over a wider range.