E
A
B. The first and second posterior intercostal arteries are branches of the superior intercostal artery, ehich in turn is a branch of the subclavian artery. The subclavian arteries arise proximal to the obstruction and are therefore unaffected
D. The intercostal nerves and blood vessels run forward in the subcostal groove of the upper rib in the intercostal space. They are arranged from above downward as follows: vein, artery, and nerve.
D. The apex of the heart can usually be felt in the fifth left intercostal space 3.5 in. (9 cm) from the midline.
C. The pulmonary valve guards the pulmonary orifice and has three semilunar cusps attached by their curved lower margins to the arterial wall.
B. The pericardial cavity lies between the parietal and visceral layers of the serous pericardium.
B. The motor innervation of the diaphragm is sup- plied only by the phrenic nerve (C3–5).
D. The thymus lies in the superior mediastinum and when enlarged may extend into the neck
C. On inspiration, the abdominal muscles relax to accommodate the abdominal viscera as the diaphragm descends.
47. When passing a needle through the chest wall and into the pleural cavity in the midaxillary line, the following structures will be pierced except which? A. The external intercostal muscle B. The skin C. The parietal pleura D. The levator costarum E. The internal intercostal muscle
D. The levator costarum muscles are small accessory muscles of inspiration found on the back of the chest wall alongside the vertebral column.
B. The apex of the pyramidal-shaped bronchopulmonary segment points toward the lung root.
E. The right principal (main) bronchus gives off the superior lobar bronchus before entering the hilum of the right lung. The left principal bronchus gives off the superior lobar bronchus after entering the left lung.
B. On contraction, the diaphragm descends and thus increases the vertical diameter of the thoracic cavity and reduces the intrathoracic pressure.
B. The cardiac notch of the left lung lies in the upper lobe.
C. The manubriosternal joint becomes less mobile with age. Eventually, the manubrium becomes joined with the body of the sternum by bone.
B. At the level of the sternal angle, the left recurrent laryngeal nerve arises from the left vagus nerve, hooks beneath the arch of the aorta, and ascends to the neck. The right recurrent laryngeal nerve arises from the right vagus nerve in the neck and hooks beneath the right subclavian artery; the right recurrent laryngeal nerve does not enter the thorax.
54. The following structures open into the right atrium except which? A. The superior vena cava B. The coronary sinus C. The anterior cardiac vein D. The inferior vena cava E. The right pulmonary veins
E. By entering the left atrium, the two right pulmonary veins and the two left pulmonary veins return oxygenated blood to the heart.
55. The conducting system of the heart is composed of the following structures except which? A. The Purkinje plexus B. The deep cardiac plexus C. The sinuatrial node D. The atrioventricular bundle E. The atrioventricular node
B. The deep cardiac plexus is an autonomic nerve plexus that lies outside the heart and below the arch of the aorta.
C. The anterior interventricular artery is a branch of the left coronary artery.
D. The most richly oxygenated blood reaches the brain via the internal carotid arteries. The abdominal aorta contains blood from the right ventricle, the pulmonary trunk, and the ductus arteriosus; but this blood is poorly oxygenated.
58. Pain arising in the heart is commonly referred to the following skin areas except which? A. Up into the neck and jaw B. Down the medial side of the arm C. The point of the shoulder D. The epigastric area E. Over the sternum
C. Pain arising from the myocardium ascends to the central nervous system through the cardiac branches of the sympathetic trunk and enters the spinal cord through the posterior roots of the upper four thoracic nerves. This pain is not felt in the heart; rather, it is referred to the skin areas sup- plied by the upper four intercostal nerves and by the intercostobrachial nerve (T2). The intercosto- brachial nerve communicates with the medial cu- taneous nerve in the upper part of the arm. A certain amount of spread of nervous information occurs within the central nervous system, because the pain is sometimes felt in the neck, the jaw, and the epigastrium, Cardiac pain is not referred to the point of the shoulder.
A patient is examined in the standing position with a left-sided pleurisy.
59. Where would you expect the pleural fluid to gravitate down to? A. The oblique fissure B. The cardiac notch C. The costomediastinal recess D. The costodiaphragmatic recess E. The horizontal fissure
D. The costodiaphragmatic recess is the most dependent part of the pleural cavity.
A patient was seen in the Emergency Department in cardiac arrest.
60. During cardiopulmonary resuscitation the posterior surface of the heart was compressed by which of the following structures? A. The body of the sternum B. The heads of the ribs C. The tracheal bifurcation D. The inferior vena cava E. The bodies of the vertebrae
E.