OMS1- CRS I

thoracic vertebra

have costal facets where ribs will articulate with vertebral bodies

• superior and inferior demifascets on vertebral bodies that make up the articulation with the ribs when put together. Except rib one, where T1 has a complete fascet

• transverse costal facets on transverse processes where rib tubercles articulate while running under the transverse process (although ribs 11-12 do not have costotransverse joint as they do not have tubercles)

parts of sternum

• jugular notch

• manubrium

• body

• xiphoid process

• on sides are articular facets for clavicle and costal cartilage

sternal angle

formed from manubrium articulation with the body, major landmarks or orientation

• corresponds to second costal cartilage (easier to find than rib one)

• T4/T5 intervertebral level, forms transverse thoracic plane (separted superior and inferior mediastinum)

types of ribs

• True Ribs (1-7): have own costal cartilage that articulates to sternum

• False ribs (8-10): costal cartilage joints cartilage above instead of going to sternum

• floating ribs (11-12): no anterior attachment. more mobile.

what is in the costal groove?

on interior and inferior aspect of rib, contains intercostal vein, artery, and nerve.

• important for invasive procedures

• a thoracentesis needle should be immidiately superior to rib

atypical rib features: rib 1

• scalene muscles attachments

• subclavian artery/vein attachment

• brachial plexus

atypical rib features: rib 2

attachments for serratus anterior

whis ribs articulate with 1 vertebral body?

ribs 1, 10, 11, 12

sternocostal joints

• 1st rib joint: syncondrosis (hyaline cartilage => immobile)

• ribs 2-7 are synovial plane joints

costochondrial joint

between ribs and costal artilage

• syncondroses joints

• little to no movement

stuctures entering thoracic aperture

aka throacic inlet, opening boardered by rib one

• trachea

• esophagus

• apex of lungs

• great vessels

• vagus nerves

• phrenic nerves

• sympathetic trunks

inferior thoracic aperture boundaries

• T12

• Ribs 11-12

• costal margin

• xiphisternal joint

• closed by diaphram

how are intercostal spaces named?

named for the rib above it

phrenic nerve

arises from C3-C5

• C3, 4, 5 keep the diaphragm alive

• enters thorax anterior to subclavian artery

• passes anterior to lung root then a long pericardium to diaphram

diaphragmic openings

I 8 10 Eggs At 12

• T8: caval opening (inferior vena cava)

• T10: esophagus

• T12: aorta

rib movement- pump handle

for ribs 2-6

• anterior aspect and sternum of ribs move upwards and forward

• increases chest depth (AP diameter)

rib movment- bucket handle

in ribs 7-10

• ribs elevate, lateral aspect move outward/upward

• increases thorax transverse diameter

• overall, increasing thoracic volume creates a negative pressure gradient so air naturally flows into lungs

rib movement- caliper motion

in floating ribs (11-12)

• has greater mobility, anterior aspect moves laterally during inhalation

• increases expansion of lower thoracic cavity

what ribs are most commonly fractured

ribs 5-9 since they have little protection over the lateral thoracic wall.

• most dangerous ribs to get fractures are 1-2 due to neurovasculatiue structures

• ribs 9-12 are more mobiles and fracture less, but pose an organ damage risk

mediastinum boundaries

• superior: superior thoracic aperture

• lateral: parietal pleura

• inferior: diaphram

• anterior: ribs

• posterior: thoracic vertebrae bodies

inferior mediateinum divisions

• anterior: in front of heart

• middle: heart

• posterior: behind heart

superior mediastinum boundaries

• supeiror thoracic aperture

• transverse thoracic plane

• manubrium

• T1-T7 vertebral bodies

superior mediastinum contents

superficial to deep

• thymus: anterior to fiberous pericardium, aorta, and great veins. posterior to manubrium

• brachiocephalic veins

• superior vena cava

• aortic arch plus branches

• phrenic nerve

• vagus nerve

• trachea

• esophagus

brachiocephalic veins

fusion of internal jugular and subclavian veins

• anterior to aortic arch branches, trachea, vagus nerve

• left is longer than the right since it crosses over to right side of heart to drain into superior vena cava

superior vena cava

drops into median mediastinum to heart

• anterior to trachea and right vegus nerve

• right of the ascending aorta and brachiocephalic trunk.

aortic arch

• starts to curve at TV4/TV5. once it drops, it becomes descending aorta at that level

• arches towards the back over left lung root

• 3 banches: brachicephlic trunk, left carotid artery, left subclavian artery

• attaches to pulmanary trunk through ligamentum arteriosum

vagus nerve

enters superior mediastinum lateral to common carotid arteries, posterior to lung root (phrenic is anterior)

• parasympathetic and visceral sensory to thoracic and abdominal viscera

• anterior vegal trunk travels with esophagus into abdomen

• posterior vagal trunk travels with trachea into abdomen

left recurrent laryngeal nerve

loops under aortic arch to ascend to larynx

• aortic aneurysm can cause voice issues

trachea

• starts an inferior boarder of cricoid cartilage (C6)

• bifurcates at TV4/TV5

• posterior to great vessles

esophogus

• continuation of pharynx starting at C6

• posterior to trachea, at T10 exits thorax at the esophageal hiatus of diaphram

• narrowing points: Pharyngoesophageal junction, aortic arch and tracheal bifurcation, diaphragm.

anterior mediastinum contents

• part of thymus

• fat and connective tissue

• lymph nodes

• sternopericardial ligaments

middle mediastinum contents

• heart (left atrium is anterior to esophagus)

• great vessels

• phrenic nerves => anterior to lung roots

• main bronchi lateral to heart

• esophagus

posterior mediastinum contents

• descending thoracic aorta: passes through diaphragm at aortic hiatus (T12)

• Azygous system of veins: ascends vertebral column, arches over right lung to superior vena cava

• thoracic lymphatic ducts

• thoracic splanchnic nerves

azygous system of veins

azygous vein is supplied by:

• hemiazygous vein: on left side, ascends vertebral column and drains around T9

• Accesory hemiazygous vein: descends on left side, crossed to azygous at T8

thoracic duct

major lymphatic drainage of body, driven by diaphragm motion

• starts at cisternae chyli (large lyphatic duct that collect lymph from lower body) at L2

• ascends behind esophagus on right

• crosses to the left around T5, drains to left venous angle (where subclavian and internal jugular veins fuse)

thoracic splanchnic nerves

pregaglionic sympathetic fibers off the sympathetic chain (most of thoracic wall), will synapse at prevertebral ganglia in abdomen.

• Greater splanchnic nerves (T5-T9)

• Lesser splanchnic nerves (T10-T11)

• Least splanchnic nerves (T12)

diaphram development

starts in week 4, after embryo folding. starts in cervical region and body will elongate around that. phrenic nerve will elongate as well

• steptum transversum: a mesnchyme partition between embryonic thorax and abdomen

• pleuroperitoneal membranes: grows in between thoracic and abdominal cavity. Two, directly inferior to where lungs will grow and continuous with septum transversium

• mesentery of the esophagus: surround esophagus

• muscles cells will arise from cervical somite mytotomes and fuse with membranous complex.

diaphramatic hernia

caused by failure of pleuroperitoneal membranes to grow across intramembranous body cavity. typically on the left

• abdominal organs can extend into the thorax, shifting the mediastinum to the right. underdevelopment of lungs

• with surgery, 70% survival

respirtory development

starts in 4th week, 5 stages. “Early pulms can’t suck air”

1. embryonic

2. pseudoglandular

3. canalicular

4. saccular (past this point, respiration is possible)

5. alveolar

embronic stage of respiratory development

• lung bud appears, starts at gut tube. aka Laryngotracheal diverticulum. Will start to bifurcate into Bronchi, Bronchi bifurcate into lobar bronchi, lobar into segmental.

• pulmonary veins and artery start to develop

• lined by endoderm

• cartilage, muscles, and CT (visceral pleura) arises from splanchnic mesenchyme surrounding lung bud during development

• somatic mesoderm forms parietal pleura

separation of primordial pharynx

in 4th week

• lung bud separates

• tracheoesophageal folds must develop to separate GI from resp.

• fold will fuse to form septum, forms a distinct esophagus dorsally and larngeotrachial tube ventrally

trachesophageal fistulas

congenital defect in the foregut structure separation

• most common (85% of cases) is when the proximal end of esophagus is a dead end and distal end of esophagus is used to trachea. can’t eat, air in abdomen

• esogagus can be disconinuous

• communication between trachea and esophagus

• esophagus can connect to trachea to food goes into lungs

• esophagus can pass through trachea

visceral pleura

• from splanchnic mesoderm

• line parenchyma of lungs, is integrated into lungs

parietal pleura

• from somatic mesoderm

• lines thoracic body wall

pseudoglandular phase of respiratory development

6-16 weeks

• conducting airways and terminal bronchioles develop

• immature neuronal network

• pre-acinar blood vessels

canalicular phase of embryonic development

16-26 weeks

• primative alveoli, terminal bronchioles elarge.

• terminal bronchioles will give rise to 2+ respiratory bronchioli, which will divide into 3-6 primative alveolar ducts

• type 1 (wall of alveolus) and 2 (produces surfactants) cells

• surfactant synthesis

• lung tissue become highly vascularized

• respiration is possible by the end of this stage

saccular phase of respiratory development

• alveoli saccules develop

• extracellular matrix and neural network mature

• surfactant forms a film in alveolar sacs (prevents collapse)

acinus

terminal bronchial + respiratory bronchile + alveoli

respiratory development nmeuonics

• Can’t breath till end of canalicular phase

• capillaries invade during canalicular phase

• surfactant is secreted in saccular stage

alveolar stage

32 weeks to 8 years

• gas exchange area continues to expand

• nerves and capillaries grow

• continued proliferation in general

how does aminiotic fluid affect lung development

breathing it in opens lungs and kidneys to development. Low amniotic fluid will impair development.

respiratory distress syndrome

usually caused by surfactant deficiency in newbonrs

congenital lung hypoplasia

often associated with low amniotic fluid

• decreased amounts of lung

• can also be caused by a diaphamic hernia

picornaviridae family characteristics

• small size

• +RNA, icosahedral hapsid

• non-enveloped

• Three genera: enterovirus, hepatovirus, parechovirus

enterovirus genera

most are acid stable, transmitted fecal-oral

• poliovirus

• coxsackie A and B

• Echovirus

• rhinovirus (although it’s very acid sensitive compared to other enteroviruses, respiratory transmission)

• numbered and lettered enteroviruses

parechovirus genus of picornaviridae

• human parechoviruses replicate in respiratory and GI tract

• diseases are asymptomatic or mild

• Type 3: sever neonatal sepsis and central nervous system damage

coxsakivirus A24

• upper respiratory infection

• may cause acute hemorrhagic conjuctivitis

coxsakivirus A16

Hand-foot-and-mouth disease

coxsakivirus B1-B6

• myocarditis

• pericarditis

• pleurodynia

• respiratory infections

enterovirus A71

• hand foot and mouth

• neurologic complications- acute flaccid paralysis

echovirus

• meningitis

• febrile illness

• rash

• respiratory infection

enterovial disease

• replicates in upper respiratory tract. wide variety of incubation times.

• summer/fall disease

• can spread into blood in primary viremia, can be stopped by memory antibodies

• migrated to target tissues: skin, muscle, brain, meningies, liver, heart

• replication in target tissues causes secondary viremia, leads to a more serious infection (such as polio => paralysis)

enteroviruses and rashes

most create some kind of rash with cold-like symptoms, especially coxsackie (A21 and A24) and echovirus (11 and 20).

• macular rashes: flat red spots

• macularpapilar rashes: flat red spots with one bump in the center

• petechial rashes: small blood blisters

• vesicular rashes: large boils

coxsaki A vs B

• A: common cold and rashes, hand foot and mouth disease, and herpangina

• B: can cause cardiac disease, responsible for half of viral cardiomyopathy. chest pain. rashes and cold-like symptoms

herpangina

typically caused by coxsackie A (8,10,16)

• lesions appear on roof of mouth, not the tounge. Causes pain and difficulty swallowing

• abrupt fever

• no skin rash

• will resolve on it’s own in a few days

• typically infects 3-10yo

hand foot and mouth

typically caused by coxsackie A16 and enterovirus 71

• lesion in mouth (including tounge), hands, and feet

• slow, progressing fever

• exanthem: macules or papules on skin

• enanthem: oral lesion in the tounge and palet

coxsackievirus A viral tagert

• ICAM-1; epithelial cells, fibroblasts, endothelial. Also rhinovirus target

• a few bind to CD55-deacy accelerating factor. mainly in cells associated with blood stream

coxsackievirus B viral tagert

CAR (or CXADR), transmembrane adhesion molecule on cardiac muscle, brain, epithelial and endothelial cells

enterovirus 71 viral target

human scavenger receptor class B member 2 (SCARB2). on several tissue types

poliovirus viral target

CD155

hepatovirus viral target

HAVCR1 (TIM-1). allows it to enter hepatocytes

coxsackie B and pleurodynia

chest pain affecting pleura with sudden onset and worsens when breathing

• abdominal pain and vomiting

• lasts 4 days before full recovery

• typically affects children under 15

coxsackie B and myocardial/pericardial infection

causes about half of the viral myocarditis infections

• inflammation of myocardium, sudden worsening of heart failure. diagnosed with inflamatory markers.

• inflamation of the pericardium surrounding heart, increased fluid within puts pressure on the heart (cardiac tamponade).

• especially coxsackie B3,4,5

how is pericarditis diagnosed

• imaging: heart has a flask-like shape

• sharp chest pain, worsens when inhaling and laying back

• pertinent positive: pain is reduced by sitting up and leaning forward

picornavairus genome

• not large

• looks like messenger RNA with a poly A tail but no 5’ cap.

• at 5’ end is a IRES (internal ribosome entry site), an RNA stem loop. will be linked to VpG protein, has more to do with transcription than tanslation

• one open reading frame creates a large polyprotein that is cleaved by 3Cpro. produces structural protein from P1, and nonstuctual protein from P2 and P3

picornovirus poly protein cleavage

• by 3Cpro

• primary cleavage: cleaves structural proteins P1,2,3

• secondary cleavage: splits proteins up into individual, mature proteins

• creates an RNA dependent RNA polymerase for amplification

picornivirus life cycle

1. virus binds to cells surface receptor through Vp1.

2. can be endocytosed or just have RNA injected into cell. VP4 is released to weaken capsid

3. RNA will undergo translation (Vpg is cleaved beforehand). protein processing.

4. at same time, genome is amplified. first transcribed into -RNA by RNA dependent RNA polymerase. then will be switched back to cyclic +RNA VpG will be added on

5. genetic material is packaged with help of VpG protein. creates provirion

6. another cleavage event produced mature virion.

picornovirus viral protein functions

• 3a: inhibits host cell protein secretion so more can be put towards viral assembly

• 3B: encodes VpG for transcription

• 3C: cysteine protease, cleaved polyprotein. has an RNA binding domain. also shuts off host cell transcription

• 3D: RNA dependent RNA polymerase

• 3CD: zymogen of 3Cpro. also recognizes cloverleaf sutucture at 5’ end of RNA to trigger replication

IRES

recruits ribosomal subunits for initiation. some host genes have these, mainly those associated with stress, mitosis, apoptosis

Vpg in transcription

• viral protein

• required for both + and - RNA sequence

• primer to start transcription, causes it to be covalently attached to genomic RNA

• needs to uridylated by 3Dpol before it can work as a primer, attached to Cre.

• once uridylated, it will cause RNA to loop around and bind to 3’ end on poly A tail. 3Dpol them elongated

IDK, come back to this later. Schizo shit

structures in the pleural cavities

• endothoracic fascia, outside parietal pleura and lines thoracic wall.

• pleura: membrane surrounding lung. outer layer is parietal pleura, inner is visceral pleura. meet and fold back into the root of the lung. forms serous sack

• costodiaphragmatic recess: the space between 2 layers of pleura along the inferior aspect as lung expands/contracts

• costomediastinal recess: space between ribs as lungs change volume

pleural margins

places you want to insert a needle

• midclavicular line: anterior, in the middle of clavical. Lung margin is rib 6, pleural margin is rib 8.

• midaxillary lines: coronal, down the center of armpit. lung margin is rib 8, pleural 10

• midscapular line: posterior, through the center of the inferior angle. lung, rib 10, pleural, rib 12

costophrenic angle

a radiography landmark. angle formed between diapragm and thoracic wall

• can be blunted by fluid in pleural cavity

pleural effusion (hydrothorax)

fluid in the pleural cavity. can be blood (hemothorax) or air (pneumothorax)

• removed through thoracentesis

structures unique to left lung

• cardiac notch along superior lobe where heart protudes

• lingula at the inferior aspect of the cardiac notch

• 2 lobes

root of lung

• where two layers of pleura fold over eachother

• contains the neurovasculatiue and trachea that enters lungs

  • pulmanary artery and veins

  • primary bronchus

  • bronchial arteries and veins

• on right lung bronchus is anterior to pulmanary artery

• on left lung bronchus is inferior to pulmanary artery

trachea

• composed of C shaped hylan cartilage

• where it sits against esophagus is just smooth muscle/connective tissue to allow for some movmenet

• bifurcates at the TV4/TV5. midline strip at the junction is called the Carina.

Primary Bronchi

sits outside the elungs. Also C shaped hyaline cartilage

• right opening is larger, so a forgine object will probably go there

• left bronchus curves up more as it enters lung

lobar bronchi

branches off main bronchi

• right lung has 3, left has 2

segmental/tertiary bronchi

segments off lobar branchi, 10 per lung. as they are functionally independent, one can be operated on and the rest of the lung is okay.

pulmanary vs bronchial circulated

• pulmanary: blood that needs to be oxygenated

• bronchial: much smaller, supplies lung tissues with blood. mainly branches off aorta

what nerves innervate pleural cavity

• parietal pleura: somatic sensory, from phrenic (mediastina aspectl) and intercostal (anterior aspect) nerves

• visceral pleura: visceral sensory innervation and autonomic pathway. localized somatic sensory pain.

• lungs: both sympathetic (cardiopulmonary splanchnic nerves) and parasympathetic affect bronchodilation.

lymph flow of lungs

flows medially then superiorly, following the bronchi

1. bronchopulmonary nodes: at hilum

2. tracheobonchial nodes on primary bronchi

3. bronchomediastinal trunks: along trachea

4. right lyphatic duct/thoracic duct

normal echocardiogram checks

• parasternal long axis (PLAX)

• parasternal short axis(PSAX)

• 4 chamber

• subcostal

procedure for an echo

low frequency, phased array transducer. have pt roll to left side.

• PLAX: 10 oclock or pt right shoulder

• PSAX: 2 o clock or pt left shoulder

• Apical: 3 o clock

• SUBC: straight to pt left

PLAX

• scan left of the sternum, to pt 10 o clock

PSAX

want to scan

• (A) Base- asess anatomy and regurgitation

• (B) mitral valve level- asseses mitral valve anatomy

• (C)papillary muscle level- assess segmental wall motion and left ventricular systolic function

• (D)apex- rule out apicalthrombosis

apical ultrasound

shows 4 chambers

SUBC

subcostal view. asses left ventrical function and right heart sive

layers of heart

• parietal pericardium- on outside of heart, made of areolar tissue and mesothelium.

• epicardium- separated from pericardium via pericardial cavity. areolar tissue and simple squamous mesothelium (epithelium of cavities). also called viseral pericardium.

• myocardium- cardiac cells with connective tissues

• endocardium- made of areolar tissue and simple squamous endothelia