THORAX / HEART FINAL Flashcards
anesthesia injection
-anesthesia of any particular area of skin usually requires injection of two adjacent nerves
-ex. anesthesia for broken rib requires injection of anesthetic agent into region of intercostal nerves superior and inferior to rib, proximal to site of fracture
muscles use during breathing
-forced:
-inspiration- external intercostal muscles
-expiration- internal intercostal muscle and rectus abdominus sheath
-dyspnea:
-recruitment of neck muscles
-sternocleidomastoid, pecs, upper trapezius, scalene muscles
-normal expiration is governed by elastic recoil pulmonary
atelectasis
-pleural cavity (normally potential space) becomes real space
-intercostal space narrowing
-displacement of mediastinum toward affected side
-when air enters pleural cavity visceral and parietal layers detach -> elastic recoil
-perfusion no ventilation
-more common on right side
-not taking deep breathes
-alveoli fill with junk
-subsegmental collapse of lung due to mucus plugging
- bronchial breath sounds heard in periphery (instead of vesicular)
lymph in lungs
-carry phagocytes
-ingest carbon particles from inspired air
-smokers -> mottled gray
subclavian artery compression
-apex of lung
-scalene muscles
-supernumerary C7 rib
-thoracic outlet syndrome -> costoclavicular syndrome
lesser diaphragmatic apertures
-2 in right crus of diaphragm- transmit greater and lesser right splanchnic nerves
-3 in the left crus of diaphragm- transmit greater and lesser left splanchnic nerves as well as hemiazygos vein
-under the medial arcuate ligament- usually transmit sympathetic trunks
-under lateral arcuate ligament- subcostal nerve and vessels
-left phrenic nerve pierces dome of the left hemidiaphragm
-internal mammary artery thorough sternal costal gaps
rib movement / percussion
-water pump
-increase/decrease anterior posterior diameter of lungs according to diaphragm
-percuss it posteriorly to measure -> diaphragmatic migration
-phrenic nerve pace maker for diaphragm paralysis
-C 3, 4, 5 keep the diaphragm alive
numbing of spinal nerves
-numb posterior region around spine when pt has significant nerve pain
-allows patient to breathe deeply -> prevents pneumonia and atelectasis
-catheter two fingers away from midline that infuses fluid with LONG acting anesthetic
-ancupump (grenade)
dead space
area of lung ventilating but not perfused -> no gas exchange
shunting
area of perfusion but no ventilating -> blood is passing by with no gas exchange
VQ
-interface between alveoli and capillary
-VQ ventilation perfusion
-areas of lung that are ventilating need to be perfused -> gas exchange
-gas exchange doesnt happen until level of bronchial
left internal thoracic artery
-internal mammary artery
-used for bypass conoid
-comes off the left subclavian
blood supply to lungs
-pulmonary and bronchial supply
-rarely infarct!
thorax imaging
-costophrenic angle -> blunt -> pleural effusion
-costocardiac angle
-costocardiac triangle -> where IVC enters RA -> area can become cystic -> pericardial cysts
-costophrenic- sharp angle
-left costophrenic angle is lower due to heart weighing it down
-blunt angle -> pleural effusion
-Ds method- circle aortic knob -> 45 degree angle -> midline -> carina
kehrs sign
-pt laying down with legs elevated
-referred pain to tip of left shoulder
-sign of fluid / blood in cavity
-often spleen damage
-this is bc diaphragm is innervated by superior nerves
left upper lobe pneumonia
-heart loses silhouette due to obscured by left UPPER lobe pneumonia involving the lingula lobe
-left low lobe pneumonia -> density in back of heart -> Still can see cardiac border
-lower lobe lesion is located retrocardiac
tension pneumothorax
-tear in parenchyma -> pleura leaks
-air collects -> pneumothorax
-pressure increases so high -> shifts to contralateral side -> displaces mediastinum -> kink off vena cava -> decrease return -> no blood to heart -> tension pneumothorax
-heart shifts to unaffected side
-no breath sounds on that side
-clinical diagnosis
-bleb pops can cause
-FIRST decompress with thoracocentesis (midclavicular 2nd space) -> simple pneumothorax
-then chest tube
pneumothorax + pleural effusion x-ray
-would show has a flat line of fluid collection on imaging
-meniscus line suggests just pleural effusion
right lower lobe pneumonia
-mimics appendicitis due to T10 dermatome
T4
nipple line
T7/T6
xiphoid process
tension pneumothorax vs atelectasis
-pneumothorax pushes away
-atelectasis- pushes towards
pancoast tumor
starts at apex of lung
Paradoxical Embolism (PDE)
-occurs when a thrombus crosses an intracardiac defect into the systemic circulation.
oblique pericardial sinus
-within pericardium
-blind recess posterior to the heart
-potential space
-cant completely pass through- pocket
-reflects around pulmonary veins, IVC, and esophagus
-oblique and transverse sinus created by folding of fetal primordial heart tube
VAN to pericardium
ARTERIAL
-pericardiophrenic artery (branch of internal thoracic artery)
-smaller branches of:
-musculophrenic artery (terminal branch of internal thoracic artery)
-bronchial
-esophageal
-superior phrenic arteries
-coronary arteries supply the visceral layer (muscle wall, epicardium)
VENOUS
-pericardiacophrenic veins (tributaries of the brachiocephlic)
-tributaries of the azygos venous system
NERVES
-sensory- phrenic
-pain referred to the skin of ipsilateral shoulder
-vagus nerve (CN X)
-sympathetic trunks- vasomotor contribution
cardiac tamponade
-pericardial effusion large enough -> reduce ability of blood fill and leave heart -> cardiac tamponade
-fluid, pus, blood -> injury or perforation of weak area after MI
-blood drained to allow proper filling and ventricular contraction
-cardiac collapse when ventricles cant contract properly
-between fibrous pericardium and visceral layer
-BECKS TRIAD:
-1. decreased APP- hypotension
-2. venous distention- jugular neck veins
-3. muffled heart sounds
heart auscultation
-mitral valve- 5th intercostal space -best heard at apex -> mitral regurgitation
-tricuspid- 4th-5th intercostal space regurgitation or VSD
-aortic- 2nd intercostal space -> on the right bc of aortic arch- aortic stenosis
-pulmonic- left 2nd intercostal space- pulmonic stenosis
-left sternal border- aortic/ pulmonic regurgitation
sinus venarum
smooth walled posterior wall on which SVC, IVC and CS open
PFO
-patent foramen ovale
-paradoxical embolism
-enlarges right atrium, ventricle, and pulmonary trunk
-stroke
right ventricle features
-septal, anterior, posterior papillary muscle
-supraventricular crest- thick muscular ridge separates muscular inflow part from smooth wall of outflow
-outflow is conus arteriosus (infundibulum)
-septomarginal trabeculae- moderator band that carries right AV bundle branches to anterior papillary muscle -> conduction
VSD
-ventricular septal defect
-hole in the membranous part of interventricular septum (upper part)
-decrease CO
-venous supply goes into systemic
-increases pulmonary blood flow
-causes pulmonary disease
-may cause cardiac failure
atrial fibrillation
-atrial systole -> dissipation of electrical signal and contraction
-abnormal p wave (beat)
-chaotic electrical activity
-quivering behavior
-increase likelihood of stroke, ischemic bowel event, ischemic limb etc -> bc blood clot can form in atrial auricle-> systemic circulation
-fluttering
aortic vestibule
-smooth part before aortic valve
-no resistance
-analogous to conus arteriosus
supply to coronary sinus
-aortic sinuses- spaces at the origin of the ascending aorta between wall and cusp
-3 cusps (right, left and non-coronary posterior
-backflow of blood due to recoil of elastic aorta -> causes filling of R&L coronary arteries
-during diastole -> blood back flows and pools in cusps -> supplies the right and left coronary arteries
-posterior cusp is non coronary
coronary artery supply
-myocardium
-right marginal artery- RV and apex
-left coronary- LA, LV, septum, AV bundle
-left anterior descending -> RV, LV and septum
-left circumflex- LA and LV
-left marginal artery- comes off left circumflex -> supplies LV
-posterior interventricular artery- supplies RV and LV and septum
venous drainage
-coronary sinus
-one of 3 things emptying into RA
-great cardiac vein contributes
-middle cardiac vein, small cardiac vein
-place a pacemaker wire into the coronary sinus and track this out to lateral wall and leaving pacemaker wires in the coronary sinus extended out into smaller vein -> Allows for pacing of LV
-wire in RA, RV, and coronary vein -> biventricular pacing (pacing of both ventricles simultaneously)
lymph drainage of heart
-subepicardial lymphatic plexus
-follow the coronary arteries
-inferior drainage from tracheobronchial lymph nodes on the right side
RA / RV surgery
-AV node will pass from RA into RV
-valvular disease or surgery here (especially tricuspid) -> interrupt cardiac skeleton -> conduction system disease -> may need pacing
pericarditis
-exacerbated by cough
-edema
-rustle of silk auscultation
-chronic -> calcify -> decrease efficiency
-pericardial effusion can develop with inflammatory diseases -> cardiac tamponade
stenosis
-increase pressure
-requires more force to pump blood past
symptoms of heart failure
-rapid thready pulse
-murmur
-abnormal location of auscultation
-enlarged heart
-swollen and cyanotic legs and feet
-bloated stomach
-fluid around the lungs- LV -> LA -> lungs (backup)
-when laying down ORTHOPNEA -> blood regurgitates from LV -> LA -> lungs
-more volume going to heart when laying down (retributed from legs)
-even more SOB laying down
pericardiocentesis
-left sternocostal angle
-5th-6th intercostal space
-possible due to cardiac notch of left lung
-can also be done by xiphocostal angle -> superoposteriorly
most common sites of myocardial infarction
-LAD
-right coronary artery
-circumflex branch
-necrosis = MI
-MC cause of ischemic heart disease is coronary artery insufficiency from atherosclerosis
coronary bypass graft
-coronary artery obstruction of severe angina
-great saphenous vein is preferred
-1. diameter is > or equal to coronary
-2. easily dissected from lower limb
-3. lengthy portions without valves/branching
-if valve is present flip it upside down
-radial artery is also common
-surgical anastomosing internal thoracic artery with coronary artery
coronary angioplasty
-percutaneous transluminal coronary angioplasty -> balloon inflates
-Percutaneous coronary intervention (PCI)
-stretch artery
-thrombokinase- enzyme that dissolves
-rigid/semirigid mesh stents put in after dilation -> balloon inflates
echocardiogram
-detects fluid
-doppler echocardiogram- demonstrates flow through heart -> valve stenosis, regurgitation, septal defects
cardiac referred pain
-ischemia and accumulation of metabolic products stimulate pain (nothing else)
-noxious stimuli in the heart -> refers to
-superficial part of body -> Ex. skin on medial aspect of left upper limb
-cardiac sensory nerves enter at T1-T4/T5 especially on left side
-referred pain to structures innervated at this same level
AV and SA node supply
-most common cause of conducting system damage -> CAD
-LAD supplies AV bundle
-RCA branches supply SA and AV nodes
-damage to AV bundle/node -> heart block -> excitation doesnt reach ventricles
-when both bundles are blocked -> ventricles beat independently (slowly)
-if only one branch is blocked -> 1 ventricle beats asynchronously
aneurysm of ascending aorta
-not protected by pericardium (beginning part is)
-blood rush hits hard here due to lack of support from pericardium
-localized dilation
-chest pain that radiates to back
-can compress traches, esophagus, recurrent laryngeal nerve -> difficulty breathing and swallowing
coarctation of aorta
-stenosis
-narrowing
-obstructs blood flow to inferior body
-common site- ligamentum arteriosum
-coarctation below ligamentum arteriosum (postductal coarctation) -> circulation is still ok bc of intercostal and internal thoracic arteries
percussion of heart
-density of size of the heart
-3,4,5 intercostal spaces
-from right to left axillary line
-resonance to dullness
CVA / stroke
-cerebrovascular accident
-occlusion of cerebral artery
-usually from clots formed in LA
stenosis
-valve cant open fully
-narrowing
-slows blood flow
-requires more force to pump past -> increase pressure
regurgitation / valve insufficiency
-valve cant close fully
-nodule formation and scarring prevents
turbulence
-restriction of flow (stenosis) and blood flow through narrow opening into larger space produce turbulence
-creates eddies (small whirlpools) -> produce vibrations -> murmurs.
-Superficial vibrations -> thrills -> may be felt on the skin over area of turbulence
prolapsed mitral valve
-leaflets are enlarged, redundant or floppy
-extending back into LA during systole
-blood regurgitates into LA when LV contracts
-murmur
aortic valve stenosis
-MC
-left ventricular hypertrophy
-MC results from degenerative calcification
pulmonary valve stenosis
-valve cusps are fused
-narrow central opening
-infundibular pulmonary stenosis- conus arteriosus underdeveloped -> restriction of right ventricular outflow
-degree of hypertrophy of RV is variable.
ischemia vs infarction
-infarction -> tombstone
-ischemia -> depression
-ischemia can lead to infarction
