Mediastinum Clinical Correlations Flaschards

Front 1

mediastinoscope

Back 1

an endoscope, used to examine the mediastinum and conduct minor surgery, inserted through a small inceision at the root of the neck, just superior to the jugular notch, anterior to trachea

Front 2

mediastinoscopy

Back 2

use a mediastinoscope to view or biopsy mediastinal lymph nodes

Front 3

Widening of mediastinum with reference to mediastinal subdivisions

Back 3

usually viewed with chest radiographs, often observed after trauma resulting from a head-on collision which produces hemorrhaging into the medistinum from lacerated great vessels, can also be caused by malignant lymphoma which enlarges mediastinal lymph nodes, also associated with congestive heart failure

Front 4

surgical significance of the transverse pericardial sinus

Back 4

after the pericardial sac is opened anteriorly, a finger can be passed through the transverse pericardial sinus posterior to the aorta and pulmonary trunk, surgeons can clamp these arteries and stop or divert the circulation of blood here

Front 5

pericarditis

Back 5

inflammation of the pericardium, usually causes chest pain, friction of the roughened surfaces sounds like th rustle of silk when listening with a stethoscope over the left sternal border and upper ribs

Front 6

pericardial effusion

Back 6

passage of fluid from pericardial capillaries into the pericardial cavity, or an accumulation of pus, usually occurs with congestive heart failure

Front 7

congestive heart failure

Back 7

a heart that fails to pump out blood at the same rate that it receives it (fails to maintain blood circulation

Front 8

cardiac tamponade

Back 8

heart compression, occurs from reducing expansion of the heart, limiting the amount of blood the heart can receive thus reducing cardiac output, is potentially lethal bec. the heart is compressed and circulation fails, can also occur from having blood in the pericardial cavity resulting from perforation of a weakened area from a heart attack or stab wounds

Front 9

pericardiocentesis

Back 9

drainage of fluid from the pericardial cavity, used to relieve cardiac tamponade, done by inserting a wide-bore needle through the left 5th or 6th ICS near the sternum (the bare area of the pericardium), or by entering the infrasternal angle and passing superoposteriorly

Front 10

positional abnormalities of the heart

Back 10

caused by abnormal folding of the embryonic heart, causes dextrocardia

Front 11

dextrocardia

Back 11

position of heart is reversed, where the apex of the heart is to the right instead of left, mirror images of the great vessels as well

Front 12

percussion of the heart

Back 12

percussion (density and size of heart), tested by creating vibrations by tapping the chest while listening and feeling for differences in soundwave conduction, performed at the 3rd-5th ICS

Front 13

atrial septal defects (ASD)

Back 13

congenital, incomplete closure of the oval foramen, these small openings cause no hemodynamic abnormalities
-clinically significant, allow oxygenated blood from the lungs to be shunted from the left atrium through the ASD into the right atrium, causing enlargement of the right atrium and ventricle and dilation of the pulmonary trunk, leads to hypertrophy of the right atrium and ventricle

Front 14

ventricular septal defects (VSD)

Back 14

occur on the membranous part, but can also occur on the muscular part of the IVS, rank first on all cardiac defects, causes a left to right shunt of blood through the defect, INC pulmonary blood flow, which causes hypertension and maybe ardiace failure (bec. of higher pressure on left side)

Front 15

thrombi

Back 15

clots, can become dislodged and enter the peripheral arteries

Front 16

stroke

Back 16

occlusion of an artery supplying the brain

Front 17

cerebrovascular accident (CVA)

Back 17

which may affect vision, cogntion, or motor function of parts of the body controlled by the damaged area of the brain

Front 18

stenosis (valvular heart disease)

Back 18

narrowing, failure of a vlave to open fully, slowing blood flow from a chamber, cause INC workload on heart

Front 19

insufficiency (valvular heart disease)

Back 19

failure of the valve to close completely, usually owing to nodule formation on the cusps so that the edges do not meet or align

Front 20

murmurs

Back 20

audible vibrations caused by turbulence

Front 21

thrills

Back 21

superficial vibratory sensations, may be felt on the skin over an area of turbulence

Front 22

valvuloplasty

Back 22

valve replacement

Front 23

mitral valve insufficiency (mitral valve prolapse)

Back 23

insufficient valve with one or both leaflets extending back into the left atrium during systole, produces murmur, chest pain and fatigue

Front 24

pulmonary valve stenosis

Back 24

valve cusps are fused, with narrow central opening, conus arteriosus is underdeveloped in infundibular type, produce a restriction of right ventricular outflow, hypertrophy of right ventricle

Front 25

pulmonary valve incompetence

Back 25

incomplete closure of pulmonary cusps, heart murmur

Front 26

aortic valve stenosis

Back 26

most frequent valve abnormality, result of degenerative calcification, left ventricular hypertrophy

Front 27

aortic valve insufficiency

Back 27

results in aortic regurgitation, producing a heart murmur and a collapsing pulse (forcible impulse that rapidly diminishes)

Front 28

coronary artery disease (CAD)

Back 28

is one of the leading causes of death, result in a reduced blood supply to the vital myocardial tissue

Front 29

infracted

Back 29

rendered virtually bloodless, occurs from an occlusion in a major artery

Front 30

necrosis

Back 30

pathological tissue death

Front 31

three most common sites of coronary artery occlusion

Back 31

1. anterior IV (LAD) branch of the LCA
2. RCA
3. circumflex branch of the LCA

Front 32

myocardial infarction (MI)

Back 32

when an area of myocardium has undergone necrosis

Front 33

atherosclerotic process of MI

Back 33

results in lipid accumulations on the internal walls of the coronary arteries, begins during early adulthood and slowly results in stenosis of the lumina of the coronary arteries

Front 34

myocardial ischemia

Back 34

insufficient blood supply to the heart, may result in MI

Front 35

angina

Back 35

pain that originates in the heart, result of ischemia of the myocardium, narrowed and hardened coronary arteries

Front 36

coronary bypass graft

Back 36

done to remove an obstruction of the coronary circulation, commonly use the radial artery, a coronary bypass graft shunts blood form the aorta to a stenotic coronary artery to INC the flow distal to the obstruction (provides a detour around)

Front 37

coronary angioplasty

Back 37

pass a catheter into the obstructed coronary artery, when reach obstruction, then inflate balloon pushing the plaque against the wall and INC the size of the vessel, can also use thrombokinase to dissolve the clot

Front 38

luminal blood

Back 38

blood from the heart chambers

Front 39

electrocardiogram (ECG or EKG)

Back 39

used to amplify and record the passage of impulses over the heart from the SA node

Front 40

heart block

Back 40

the ventricles will begin to contract independently at their own rate, atria contract at the normal rate, but the impulse is not transmitted to the ventricles

Front 41

bundle branch block

Back 41

damage to one of the bundle branches, excitation passes along the unaffected branch and causes a normally timed systole of that ventricle only, need cardiac pacemaker to INC the ventricular rate of contraction to 70-80 per min.

Front 42

artifical cardiac pacemaker

Back 42

inserted subQ, consists of a pulse generator or battery pack, a wire, and an electrode, produces impulses that initiate ventricular contractions at a predetermined rate

Front 43

cardiopulmonary resuscitation

Back 43

restore cardiac output and pulmonary ventilation, apply pressure to the thorax over the sternal body

Front 44

fibrillation of the heart

Back 44

multiple, rapid, circuitous contractions or twitchings of muscular fibers

Front 45

atrial fibrillation

Back 45

normal contractions of the atria are replaced by rapid irregular and uncoordinated twitchings of different parts of the atrial walls, ventricles respond at irregular intervals

Front 46

ventricular fibrillation

Back 46

normal contractions of the ventricle replaced by rapid, irregular twitching movements that do not pump

Front 47

defibrillation of the heart

Back 47

electric shock may be given to the heart through the thoracic wall causing cessation of all cardiac movements and a few seconds later the heart may begin to
beat more normally

Front 48

cardiac referred pain

Back 48

noxious stimuli originating in the heart are perceived by a person as pain arising from a superficial part of the body, the skin on the left upper limb

Front 49

visceral referred pain

Back 49

transmitted by visceral afferent fibers accompanying sympathetic fibers and is typically referred to somatic structures or areas such as a limb having afferent fibers with cell bodies in the same spinal ganglion

Front 50

anginal pain

Back 50

radiating from the substernal and left pectoral regions to the left shoulder and the medial aspect of the left upper limb

Front 51

About the thymus

Back 51

a prominent feature of the superior mediastinum during infancy and childhood, important in the development and maintenance of the immune system, at puberty it begins to diminish in size, at adulthood it is replaced by adipose tissue but still produces T-lymphocytes

Front 52

aneurysm

Back 52

localized dilation that may develop bec. of a strong thrust of blood when the left ventricle contracts, will be evident on a chest film as an enlarged ascending aorta, usually complain of chest pain that radiates to the back

Front 53

right arch of the aorta

Back 53

formed when the arch of the aorta curves over the root of the right lung and passes inferiorly on the right side

Front 54

double arch of the aorta

Back 54

forms a vascular ring around the esophagus and trachea

Front 55

coartaction of the aorta

Back 55

arch of the aorta has an abnormal narrowing (stenosis) that diminishes the caliber of the aortic lumen, producing an obstruction to blood flow to the inferior part of the body, commonly found near the site of the ductus or ligamentum areriosum,

Front 56

injury to the recurrent laryngeal nerves

Back 56

recurrent laryngeal nerves supply all intrinsic muscles of the larynx, could become involved in a bronchogenic or esophageal carcinoma, enlargement of mediastinal lymph nodes, injury causes change in voice

Front 57

About the esophagus and its sites of blockage

Back 57

esophagus descends into the posterior mediastinum, the primary posterior relationship of the base of the heart, there are no constrictions in the walls, but when something is swallowed the arch of the aorta, the left main bronchus and the diaphragm compress its walls, these structures also cause swallowed substances to travel slower when passing through, show where these objects are most likely to lodge

Front 58

Laceration of the thoracic duct

Back 58

during an accident or lung surgery, result in lymph escaping into the thoracic cavity at rates ranging from 75 to 200 mL, also possible for lymph to enter the pleural cavity, remove the fluid through thoracentesis or ligate the thoracic duct