USMLE MCQ Step1 - MCQ

USMLE MCQ Step - MCQ
A 7 month old infant with multiple medical problems required intravenous access. The medical student asked the radiology resident to help place the long peripheral line in the left arm. Once the line was placed, a chest x ray was obtained. please see the attached link. The next step in the management of the infant is?

a. fire the medical student
b. fire the resident
c. remove the line
d. hide the x ray
e. hide the infant
f. leave the line alone
g. put a new line in the right arm
h. pull the line until it is just at the tip of the heart

ANS: The chest x ray shows a PICC line placed in the arm and entering the left axillary and subclavian vein. Then the line enters the heart through the LEFT SUPERIOR VENA CAVA, goes through the coronary sinus and comes out of the inferior vena cava. This is not abnormal. All of us have one superior vena cava on the RIGHT. Some infants born with congenital heart disorders also have a left superior vena cava. The left superior vena cava then connects to the coronary sinus in the right atrium. THE LEFT SUPERIOR VENA CAVA IS NORMAL. Sometimes it may open into the left atrium and this is known as an unroofed coronary sinus and acts like an atrial septal defect. In general, the shunting is minimal and nothing needs to be done.