(answer a)vena cava bring venous blood to in the right atrium. Oxy-
genated blood from the lungs is brought to the left atrium (answer b)by
the pulmonary veins. The right ventricle (answer d)receives blood from
the right atrium.
349.The answer is c.(Moore and Dalley, pp 140–141.)The ice pick
likely penetrated the left ventricle of the heart, causing blood to leak into
the pericardial sac. The rapid filling of the pericardial space does not
allow the heart to fully expand between contractions leading to increased
venous hypertension. The result is filling of the external jugular veins.
Since the heart can only pump small quantities of the blood with each
beat, it speeds up (tachycardia). The heart sounds and apical heartbeat
soften because the blood surrounding the heart absorbs the sounds. A
hemothorax(answer a)and pneumothorax (answer b)are unlikely
since both right and left lungs sounds are normal and because of the loca-
tion of the ice pick injury. Aortic valve stenosis (answer d)wouldnot
result from a puncture wound. Deep venous thrombosis (answer e)gen-
erally occurs in the lower extremity and results in leg pain and is not
caused by a puncture wound.
350.The answer is a.(Moore and Dalley, pp 140–141.)Draining blood
from the pericardial cavity is performed by inserting a needle just under the
left tip of the xiphoid process in an effort to remove blood from the peri-
cardial cavity. This procedure is called pericardiocentesis. Blood within the
pericardial sac will cause heart failure as the fluid prevents the heart cham-
bers from expanding properly and filling with blood. Thus, the ability of
the heart to pump blood is diminished. Most of the other answers
(answers b, c, d, e)are all too cranial and would not allow access to the
pericardial space.
351.The answer is d.(Moore and Dalley, pp 120–124.)The lobe indicated
by the asterisk is the left upper (or superior) lobe. The general orientation
when viewing CTs is that the observer is looking up from the patient’s feet.
Therefore, the patient’s left is on your right, thus it can’t be a part of the
right lung (answers a, b, c).In addition, on the left, the inferior (lower)
lobe(answer e)begins relatively high in the thoracic cavity and is poste-
rior to the upper lobe.
484 Anatomy, Histology, and Cell Biology