intro to main structures of the thorax Flashcards
where does the heart lie
in the middle mediastinum of the inferior mediastinum
pericardium
divided into fibrous [outer] and serous [inner] parts which surround the heart
fibrous pericardium
tough and not distensible; attached to diaphragm by pericardiophrenic ligaments; blends into adventitia of great vessels
serous pericardium
comprises of visceral layer [epicardium] and parietal layer [lining fibrous pericardium]; potential space [pericardial cavity] between them
surfaces
anterior/sternocostal: formed mostly of right ventricle
inferior/ diaphragmatic: mostly L ventricle
posterior/ base: mostly L atrium and pulmonary vv
Pulmonary:
mostly L ventricle, in cardiac notch of L lund
heart markings
2,3,5,6
superior: from L cc2 to R cc3
Right: from R cc3 to R cc6, mainly R atrium with SVC and IVC
inferior: from R cc6 to L ics5; mainly R ventricle and part of L ventricle
Left: from ics5 to L cc2; mainly L ventricle and some of L atrium
valve positions
PAMT 3344 LLLR all valves are retrosternal in position and close to the midline. Pulmonary : medial to L cc3 Aortic: medial to L ics3 Bicuspid/mitral: medial to L cc4 Tricuspid: medial to R ics4
valve sounds
sounds are best heard downstream of valves
pulmonary: L ics2 near sternal edge- dup sound
aortic: R ics 2 near sternal edge- dup sound
bicuspid/mitral;: L ics5 at midclavicular line, lub sound,
tricuspid: L ics5/6 near lower sternal edge, lub sound
pleura
a serous membrane divided into parietal [outer] and visceral [ inner] layers which surround the lungs and contain the pleural cavities; layers also separated by a small layer of serous fluid
parietal pleura
lines thoracic cavity lateral to the mediastinum; supplied by intercostal and phrenic nn; sensitive to pain
visceral pleura
covers lung and follows lung fissures; supplied by autonomic nn
pleuritis
inflammation of the pleura- can hear pleural rub on stethoscope. leads to sharp chest pain
surfaces of the lungs
- mediastinal : slat, faces mediastinum and has impressions of mediastinal structures; contains the hilum and pulmonary ligament.
- diaphragmatic: concave and faces domes of diaphragm.
- costal: convex and faces ribs
- cervical: extends into neck, 2-3cm above medial third of clavicle, as apex, dome or cupola
what are pleural reflections?
the abrupt lines along which the pleura change direction ( reflect) from one wall of the pleural cavity to another.
occur when the costal pleura becomes continuous with the mediastinal pleura anteriorly and posteriorly , and with the diaphragmatic pleura inferiorly
surface anatomy of lungs and pleura
symmetry and close behind sternal angle [rib 2]
parallel down to rib 4.
L indented [cardiac notch] but R continues to cc6.
rib 8 at midclavicular line.
rib 10 at midaxillary line.
rib 12 at lateral border of erector spinae m
