Thorax clinical boxes + guide questions Flashcards
In elderly people, the costal cartilages undergo __________________, making them more radio_________
calcification; radiopaque
What ribs are more commonly fractured?
The middle ribs
What part of the thoracic wall moves freely when a pt has flail chest?
A sizable segment of the anterior or lateral parts of the wall
Describe the possible supernumerary ribs
1) Cervical ribs: in 1% of ppl; articulate with C7, clinically significant because they may compress spinal nerves C8 and T1, the inferior trunk of the brachial plexus (can cause tingling/ numbness on lateral forearm), or the subclavian artery (causing ischemic muscle pain)
2) Lumbar ribs: less common, only clinical significance is that they may confuse ID of vertebral levels in imaging
1) The surgical creation of an opening into the thoracic wall to enter the pleural cavity is called what?
2) What are the two types?
3) What is a better way to enter the thoracic cage?
4) What is the most common way to enter the thoracic cage?
1) Thoracotomy
2) Anterior and posterior thoracotomy
3) Laterally
4) With rib retraction (making intercostal space wider)
The sternal body is often used for what?
Bone marrow needle biopsy
1) What is sometimes cut at the median plane to gain wide entry into the thoracic cavity?
2) What are other ways this cavity can be accessed?
1) Sternum
2) Lateral thoracotomy (wide access) or thoracoscopy (less invasive)
1) What is the thoracic outlet?
2) What is a type of thoracic outlet syndrome? Describe it
1) Superior thoracic aperature (and its important arteries + nerves that pass into lower neck and upper limb)
2) Costoclavicular syndrome; compressed subclavian artery between clavicle and 1st rib causes pallor, coldness of upper limb, diminished radial pulse, esp when angle of neck and shoulder is increased.
1) What is a dislocated rib? When does it cause the most pain?
2) What is a rib separation? What are sometimes affected?
1) Rib slipping off sternum; during deep respiratory movements
2) A costochondral junction dislocation (between rib and its cartilage). In 3-10 ribs perichondrium and periosteum are sometimes torn, causing rib to move upward.
1) How can paralysis of the diaphragm be detected?
2) True or false: paralysis of one half of the diaphragm does not affect the other side because they’re innervated by different phrenic nerves
3) What happens during paralysis of diaphragm?
1) Radiographically by noting its paradoxical movement
2) True
3) The paralyzed half is pushed superiorly by abdominal viscera during inspiration (instead of descending) and descends during expiration
True or false: sternal fractures are uncommon, but when they happen the main concern is damage to the heart or underlying structures
True
stopped at 219/ 192
What provides sensation to central diaphragm, mediastinal pleura, and pericardium?
Phrenic nerve
Where do the recurrent laryngeal nerves branch off of the Vagus nerve on right and left side?
1) Right: at the level of the right subclavian artery, right recurrent wraps around subclavian artery.
2) Left: as the vagus nerve passes near the aortic arch, left recurrent wraps around aorta.
Superficially to the esophagus, the arch of aorta wraps around the carina of the ________
trachea
Aorta is slightly on the ___________ side of the vertebral bodies and SVC is slightly on the _____________side
left; right
What is the relationship of the esophagus and aorta in the posterior mediastinum relative to each other and the midline?
-Aorta is slightly on the left side of vertebral bodies and SVC is slightly on the right side
-Esophagus initially medial to the thoracic aorta, but crosses in front of it as it descends.
-As it approaches the diaphragm, it ends up anterolaterally to the aorta (further left than it).
Where do the presynaptic and postsynaptic sympathetic components of the cardiac plexus come from?
1) Presynaptic cell bodies: thoracic lateral horn T1-5(6)
2) Postsynaptic cell bodies: cervical and superior thoracic paravertebral ganglia
Where do the presynaptic and postsynaptic parasympathetic components of the cardiac plexus come from?
1) Presynaptic fibers: of the Vagus n., CN X
2) Postsynaptic cell bodies, (intrinsic ganglia): located near SA and AV node, along coronary arteries
What do sympathetic and parasympathetic input do to the heart conduction system?
-Sympathetic stimulation: increased rate and force, dilates coronary arteries
-Parasympathetic stimulation: slows heart, reduces force of ctx.
What does sympathetic stimulation do to coronary conduction system and coronary arteries during exercise?
Dilates coronary arteries
What is the relationship of the esophagus and aorta as they traverse the diaphragm?
Esophagus is anterior to aorta as they go through the diaphragm to abdominal cavity, esophagus ends superiorly (in stomach) and aorta keeps going.
At the level of the heart base in the inferior middle mediastinum, what is the general relationship of the Vagus and phrenic nerves?
-Vagus nerve runs slightly left of the median over the top of the aortic arch
-Right phrenic nerve runs laterally to superior vena cava (SVC)
-Left phrenic nerve runs laterally to the vagus nerve over the left side of the aortic arch and over the LPA
Describe the fibrous pericardium
-It’s the exterior layer that blends with central tendon.
-Its exterior surface is the epicardium (aka outer layer of myocardium)
-Appears gray
Describe the serous pericardium
-Parietal serous: Interior surface of fibrous pericardium is the parietal layer of serous pericardium
-Visceral serous layer: adheres closely to heart and great vessels
Where is the pericardial cavity?
It’s a potential space between the parietal and visceral layers of the pericardium with thin film of serous fluid
Why may clinically significant pericardial tamponade result in decreased cardiac output?
20-30cc of extra fluid can impinge heart’s ability to relax (dilate, passive process) and fill with blood because the fibrous layer of the pericardium doesn’t stretch much.
Relative to the anterior and posterior chest wall, where is the right and left ventricle located (orientation of the heart in the mediastinum)?
Right side is closer to anterior side of chest wall
The apex of the heart/ point of max intensity is what valve region for auscultation?
Mitral
Which valves are leaflet or semilunar?
Aortic and pulmonary are SL
Mitral and tricuspid are leaflet
Which valves are open and closed during contraction phase of the heart cycle (systole)?
Mitral and tricuspid are closed, aortic and pulmonary are open
Which valves are open and closed during the relaxation phase of the heart cycle (diastole)?
Aortic and pulmonary are closed, mitral and tricuspid are open
What are the 3 major components of the leaflet valve type?
Cusp (top part), tendinous cords (chordae tendineae), papillary muscles
Describe the cardiac skeleton
Non-conductive, helps separate ventricles from atria
Consists of fibrous skeleton, fibrous rings, and fibrous trigones
What is the distribution of the LCA (left coronary artery)? What are its branches?
Has LAD and circumflex branches:
1) Left atrium
2) Most of left ventricle
3) Pt of right ventricle
4) Anterior 2/3 of septum
5) AV bundle conducting system *
6) SA node (40%)
*the reason why LCA branches lead to more arrythmias
What is the distribution of the RCA (right coronary artery)? What are its branches?
Posterior IV branch
1) Right atrium
2) Most of right ventricle
3) Some of left ventricle
4) Posterior 1/3 of septum
5) SA node 60%, AV node 80%
If you have a lateral posterior coronary artery occlusion (heart attack), which coronary artery is most likely affected?
LCA (I think)
If you have a heart attack resulting in a conduction disturbance (left bundle branch block), which coronary artery is affected? Why?
LAD (anterior interventricular), because the LAD supplies blood to the majority of the left ventricle, including the tissue where the left bundle branch is located
Review the cardiac conduction cycle, valves during differ phases and correlate with the ECG tracing
Atrial depolarization: P wave, atria contract and AV valves are open to allow blood into ventricles
Atrial repolarization: not seen on EKG, AV valves close and stops contracting
Ventricular depolarization: QRS complex, ventricles contract and SL valves open
Ventricular repolarization: T wave, ventricles stop contracting and SL valves close
Why does visceral heart pain refer to the arm or shoulder?
-Transmitted by visceral afferent fibers accompanying sympathetic fiber
-Typically referred to somatic structures or areas such as the upper limb having afferent fibers with cell bodies in the same spinal ganglion and central processes that enter the spinal cord through the same posterior roots.
Describe the origin of the coronary arteries
Come from proximal part of ascending aorta and wrap around either side of the heart laterally and posteriorly
1) What is the first branch off ascending aortic arch?
2) What comes off this branch?
3) What comes off that?
1) Brachiocephalic trunk
2) Right subclavian and common carotid
3) Right axillary comes off right subclavian
1) What is the the second branch off the aortic arch? Where does it go?
2) What is the the third branch off the aortic arch? Where does it go?
1) Left carotid a.; goes up neck
2) Left subclavian; splits into left axillary and vertebral arteries
What do the supreme intercostals give off?
First and second posterior intercostal arteries
How many posterior IC arteries are there?
11 pairs that supply the intercostal spaces
Describe the bronchial, mediastinal, and esophageal arteries locations
1) Bronchial: comes from proximal third posterior intercostal artery, goes along the bronchial trees
2) Mediastinal: directly under sternum, they’re branches of internal thoracic artery
3) Esophageal: come from descending thoracic aorta around level of the heart and provide blood to esophagus
What is the first artery branch from the aorta after traversing the aortic hiatus in the diaphragm?
Celiac trunk
What makes up the anterior and posterior rectus sheath above and below the umbilicus?
1) Above umbilicus:
Anterior: EO fascia + anterior lamina of IO
Posterior: posterior lamina of IO + TA fascia
2) Below umbilicus:
Anterior: aponeurosis of all 3 muscles
Posterior: only transversalis fascia (endoabdominal fascia)
What forms the linea alba?
Fusion of abdominal muscle facias @ midline
Review the anterior peritoneal wall
1) Skin
2) Superficial fascia (SQ) is inferior to umbilicus 2 layers:
-Camper fascia – fatty layer
-Scarpa fascia – deep membranous layer
3) Investing (deep) fascia - covers external aspects of 3 muscle layers of abdominal wall and their aponeurosis
4) Endo-abdominal fascia – variable thickness, lines the internal aspect of the abdominal wall (named based on the muscle/aponeurosis it covers)
5) Extraperitoneal fat
6) Parietal peritoneum – lines abdominal cavity
What muscles make up the abdominal wall and how are they related?
1) 3 flat muscles: External Oblique, Internal Oblique, Transversus Abdominis mm.
-Form aponeurosis anterior, rectus sheath enclosing Rectus abdominis, then form linea alba at midline
-EO interdigitates with serratus anterior muscle fibers on costal surface
2) 2 vertical muscles: Rectus Abdominis, Pyramidalis mm.
What layers do you go through external from the skin to enter the peritoneal cavity?
1) Skin: The outermost layer
2) Superficial fascia: A thin layer of subcutaneous tissue above the umbilicus, and two layers below the umbilicus
-Camper’s fascia: The fatty superficial layer below the umbilicus
-Scarpa’s fascia: The deep layer below the umbilicus
3) External oblique muscle: A muscle in the abdominal wall
4) Internal oblique muscle: A muscle in the abdominal wall
5) Transversus abdominis muscle: A muscle in the abdominal wall
6) Transversalis fascia: A layer in the abdominal wall
7) Parietal peritoneum: The final layer before entering the peritoneal cavity
A pneumonectomy is the removal of what?
Entire lung
What is an alternative to the SVC/ collateral?
Bronchial veins
Describe SABA and LABA
1) Adrenergic (norepi) receptor agonist [short acting beta agonist]
2) Sympathetic
Describe SAMA and LAMA
Cholinergic receptors antagonist
Parasympathetic
What goes through the diaphragm’s caval opening?
IVC
What do the pudendal vessels supply?
The scrotum
What does the pampiniform plexus supply?
Testes
The right testicular vein dumps into what vessel? Are varicoceles more or less concerning on this side?
IVC; more concerning
