A 5-week-old infant presents with a 1-week history of progressive nonbilious emesis, associated with a 24-
hour history of decreased urine output. The infant continues to be active and eager to feed. On
examination, the infant has a sunken fontanelle and decreased skin turgor. The abdomen is scaphoid, and
with a test feed, there is a visible peristaltic wave in the epigastrium.
Which of the following is the most likely diagnosis?
A 5-week-old infant presents with a 1-week history of progressive nonbilious emesis, associated with a 24-
hour history of decreased urine output. The infant continues to be active and eager to feed. On
examination, the infant has a sunken fontanelle and decreased skin turgor. The abdomen is scaphoid, and
with a test feed, there is a visible peristaltic wave in the epigastrium. Electrolytes and a urinalysis are
evaluated. Which of the following laboratory findings are most likely to be seen in this patient?
A 5-week-old infant presents with a 1-week history of progressive nonbilious emesis, associated with a 24-
hour history of decreased urine output. The infant continues to be active and eager to feed. On
examination, the infant has a sunken fontanelle and decreased skin turgor. The abdomen is scaphoid, and
with a test feed, there is a visible peristaltic wave in the epigastrium. Which of the following is the most
appropriate next step in management of this infant?
A40-year-old previously healthy man presents with sudden onset of severe abdominal pain that radiates
from the right loin (flank) to groin. This pain is associated with nausea, sweating, and urinary urgency. He is
distressed and restless, but an abdominal examination is normal.
Which of the following is the most likely diagnosis?
A40-year-old previously healthy man presents with sudden onset of severe abdominal pain that radiates
from the right loin (flank) to groin. This pain is associated with nausea, sweating, and urinary urgency. He is
distressed and restless, but an abdominal examination is normal. Which of the following is the most
appropriate next step in management?
A25-year-old woman was involved in a motor vehicle crash and sustained a significant closed-head injury,
a pulmonary contusion, and a pelvic fracture. She is unresponsive and is ventilated in the intensive care
unit (ICU).
Which of the following is the best initial approach to the management of this patient's nutritional needs?
A 26-year-old previously healthy man was pinned under a crane at a construction site. After a prolonged
extrication, he was brought to the emergency department, immobilized on a back board and receiving
100% oxygen by mask. He is alert and complaining of chest pain with respiratory effort. On examination, he
is found to have an oxygen saturation of 90% by pulse oximetry, shallow respirations at a respiratory rate of
35/min, heart rate of 120 beats/min, and a blood pressure of 85/60 mmHg. The trachea is deviated to the
right. There is tenderness and crepitation over the left chest wall, asymmetric chest wall movement, and
decreased air entry over the left lung field. Which of the following is the most appropriate next step in the
initial evaluation and management of this patient?
A 4-year-old previously healthy girl presents to the emergency department with a 24-hour history of rectal
bleeding and dizziness. She has no other gastrointestinal symptoms. On examination, she appears pale.
Her heart rate is 140 beats/min, and she has a 20 mmHg postural drop in systolic blood pressure. The
child's abdomen is nondistended and nontender, and fresh blood and clots are in the rectal vault on rectal
examination.
Which of the following is the most likely diagnosis?
A 4-year-old previously healthy girl presents to the emergency department with a 24-hour history of rectal
bleeding and dizziness. She has no other gastrointestinal symptoms. On examination, she appears pale.
Her heart rate is 140 beats/min, and she has a 20 mmHg postural drop in systolic blood pressure. The
child's abdomen is nondistended and nontender, and fresh blood and clots are in the rectal vault on rectal
examination.
Which of the following is the most appropriate diagnostic study to order for this patient?
A 4-year-old previously healthy girl presents to the emergency department with a 24-hour history of rectal
bleeding and dizziness. She has no other gastrointestinal symptoms. On examination, she appears pale.
Her heart rate is 140 beats/min, and she has a 20 mmHg postural drop in systolic blood pressure. The
child's abdomen is nondistended and nontender, and fresh blood and clots are in the rectal vault on rectal
examination.
Definitive management of this child should include which of the following?