Thoracic cavity Flashcards
true ribs
1-7, attach via costal cartilage to sternum
false ribs
8-10, attach via costal cartilage but not directly to sternum
floating ribs
11-12, do not attach to sternum
3 openings in diaphragm
aortic hiatus, esophageal hiatus, caval opening
aortic hiatus level
T12
aortic hiatus is formed by
right and left crura
what passes through aortic hiatus
aorta, thoracic duct, and often azygos vein
esophageal hiatus level
T10
what passes through esophageal hiatus
esophagus and vagus nerves
caval opening level
T8
what passes through the caval opening
inferior vena cava and sometimes right phrenic nerve
intercostal neurovascular bundle lies between
internal and innermost intercostal muscles
intercostal veins drain into the
azygos vein
azygos vein drains into the
inferior vena cava
costomediastinal recess is located
between lungs and heart
costodiaphragmatic recess is located
between lungs and diaphragm
pleural effusion settles in
costodiaphragmatic recess
what space allows for maximal lung expansion
costodiaphragmatic recess
hilum
point of entry or exit for the bronchus and vascular structures passing in and out of the lung
costal surface of parietal pleura innervation
intercostal nerves
mediastinal and diaphragmatic surfaces of parietal pleura innervation
phrenic nerves
visceral pleura innervated by
autonomic nervous system
which side of the lung is more susceptible to aspiration
right
what muscle contracts to constrict the airway
trachealis
contents of superior mediastinum
great vessels, trachea, esophagus, phrenic and vagus nerves
divisions of inferior mediastinum
anterior, middle, posterior
contents of anterior mediastinum
tissue, fat, remnants of thymus gland
contents of middle mediastinum
heart, roots of great vessels, phrenic nerves
contents of posterior mediastinum
descending aorta, azygos vein, thoracic duct, esophagus, vagus nerves
pericardial sinuses formed by
visceral pericardium reflecting back to become parietal pericardium at roots of great vessels
function of triscupid and mitral valves
prevent backflow of blood from ventricles to atria
semilunar valves
aortic, pulmonic
atrioventricular valves
mitral, tricuspid
cusps of pulmonary valve
anterior, left, right
cusps of aortic valve
posterior, left, right
sections of mitral valve
anterior, posterior
sections of tricuspid valve
anterior, septal, posterior
pulmonary trunk location
second intercostal space
apex of the heart location
5th intercostal space, midclavicular line
most of the anterior surface of the heart is comprised of the
right ventricle
right atrium is located at
3rd costal cartilage near midline
sternal angle location
where the manubrium meets the sternum
structure at sternal angle
aortic arch, where trachea divides into primary bronchi
aortic listening point
2nd intercostal space, right sternal border
what can be heard at aortic listening point
murmur of aortic stenosis
pulmonic listening point
2nd intercostal space, left sternal border
what can be heard at pulmonic listening point
pulmonic murmurs, patent ductus arteriosus
erb’s point
3rd intercostal space, left sternal border
what can be heard at erb’s point
aortic regurgitation, hypertrophic cardiomyopathy
tricuspid listening point
5th intercostal space, left sternal border
what can be heard at tricuspid listening point
tricuspid murmurs, ventricular septal defect
mitral listening point
5th intercostal space, midclavicular line
what can be heard at mitral listening point
mitral murmurs
intercostal NVB runs between which muscles
internal and innermost intercostals
intercostal veins drain into
azygos and internal thoracic veins
intercostal arteries branch off of
thoracic aorta and internal thoracic arteries
divisions of thoracic cavity
mediastinum and two pleural sacs
plane of sternal angle
horizontal line running from junction of manubrium and body of sternum posteriorly to lower border of T4
diaphragm arises from
margins of the thoracic outlet
division between superior and inferior mediastinum
plane of the sternal angle
lungs’ only point of attachment in thoracic cavity
hilum
how much pleural fluid is in the pleural cavity
15 mL
location of thoracentesis
at or posterior to midaxillary line, 1-2 intercostal space below level of effusion but not below 8th intercostal space
the fibrous pericardium blends with
the adventitia of the roots of the great vessels and the central tendon of the diaphragm
epicardium is aka
visceral pericardium
transverse pericardial sinus location
posterior to ascending aorta and pulmonary trunk, anterior to superior vena cava
which sinus allows a surgeon to make a ligature between arteries and veins, stopping bloodflow
Transverse sinus
oblique sinus
behind the heart, surrounded by a reflection of serous pericardium around the right and left pulmonary veins
location of beginning of coronary arteries
in the aorta, adjacent to left and right cusps
what is the cardiac skeleton
4 interconnecting rings of dense fibrous connective tissue on a plane between atria and ventricles
purpose of cardiac skeleton
maintain integrity of valve openings, attachment point for cusps, separates atrial from ventricular musculature by acting as an electrical insulator
3 surfaces of the heart
sternoscotal (anterior), base (posterior), diaphragmatic (inferior)
anterior surface of the heart is covered by
sternum and 3-6 costal cartilages
enlarged left atrium can cause
dysphagia from compressing the esophagus or hoarseness from compression the left recurrent laryngeal nerve
coronary veins and arteries are located within
sulci
sulci locations
anterior and posterior (with interventricular septum) and coronary (between atria and ventricles)
posterior descending artery travels with the
middle cardiac vein
location of posterior descending artery
posterior interventricular sulcus
upper limit of the heart
R: 3rd costal cartilage, L: 2nd intercostal space at sternum
right margin of the heart
3rd costal cartilage to near 6th costal cartilage
left margin of the heart
2nd intercostal space to 5th intercostal space (midclavicular)
apex of heart located
5th intercostal space, midclavicular line
lower margin of the heart
sternal right 6th costal cartilage to apex
trabeculae carnae
muscular ridges of myocardium in both ventricles
moderator band aka
septomarginal trabecula
moderator band
band of trabeculae carnae that forms a bridge between interventricular septum and right papillary muscle
moderator band function
provides pathway for purkinje fibers so that right AV valve closes slightly before left AV valve
papillary muscles
attach to chordae tendinae to and tense just before ventricular contraction to keep valves from everting into atria
pectinate muscles
ridges in muscular portion of atria (mostly right atrium)
sinus venarum
smooth portion of atria
crista terminalis
boundary between pectinate muscles and sinus venarum in atria
auricles contain
pectinate muscles
RA is supplied by
Posterior descending artery
posterior septum is supplied by
posterior descending artery
SA node is supplied by
SA nodal artery branching off RCA
AV node is supplied by
AV nodal artery branching off RCA
Right ventricle is supplied by
right marginal artery, PDA
Posterior descending artery aka
posterior interventricular artery
posterior descending artery supplies
RA, R/LV, posterior septum
branches of RCA
PDA, right marginal, SA nodal, AV nodal
right marginal artery supplies
RV
branches of left coronary artery
LAD, left marginal, left circumflex
LAD aka
anterior interventricular artery
LAD supplies
anterior septum, anterior LV, RV
left marginal supplies
LV
branch of circumflex
left marginal
circumflex artery supplies
posterior LV, LA
Left atrium is supplied by
circumflex artery
anterior left ventricle is supplied by
left anterior descending
posterior left ventricle is supplied by
circumflex artery
right dominance
posterior descending artery is a branch of RCA
left dominance
posterior descending artery is a branch of LCA
parasympathetic innervation of the heart
vagus nerve
sensory innervation of heart
afferent nerves travel back to T1-T4 spinal cord with sympathetics
sympathetic innervation of the heart
T1-T4 levels of sympathetic trunk
phrenic nerve innervates
diaphragm, fibrous pericardium, mediastinal pleura
C3-C5 dematomes
shoulder/neck
where are heart sounds best auscultated
where turbulent bloodflow radiates, distal to the valve
S1 produced by
closure of AV valves
S2 produced by
closure of semilunar valves
trachea begins at
inferior border of cricoid cartilage
how long is the trachea
12 cm
trachea is composed of
C-shaped rings of hyaline cartilage
secondary bronchi aka
lobar bronchi
tertiary bronchi aka
segmental bronchi
bronchial arteries arise from
descending aorta
blood pathway into lungs
each branch of tracheobronchial tree is accompanied by a branch of the pulmonary artery
blood supply to lungs
bronchial arteries
impressions in medial right lung
esophageal, azygos
impressions in medial left lung
cardiac notch, aortic
visceral afferents of tracheobronchial tree
“from the Vagus”