Flashcards in Thorax Deck (50):
The withers run between which vertebrae?
How many sternebrae are there?
6 or 7
The heart is positioned between which IC spaces?
2 to 6
What are the names of the interventricular grooves and which is on the left/right side?
Paraconal interventricular groove - left; subsinuosal interventricular groove - right
The fossa ovalis is in which chamber? Where is it specifically and what is its name in the fetus?
Right atrium; depression in the interatrial septum just caudal to the intervenous tubercle; foramen ovale
What is the opening of the coronary sinus and where is it located?
The terminal end of venous drainage of the heart itself; ventral to entrance of caudal vena cava
The conus arteriosus is in which chamber?
What is the trabecula septomarginalis and where is it located?
Muscular strand from septal to parietal wall that contains Purkinje fibers; right ventricle
What structure is unique to the bovine heart?
Ossa cordis - ossified fibrocartilage
Where is the puncta maxima in the horse (left/right)?
Pulmonary - 3rd IC low
Aortic - 4th IC high
Left A-V (mitral) - 5th IC low
Right A-V - 3rd-4th IC low
What is different about the puncta maxima in the cow?
Left A-V - 4th IC low
Scapula is in which IC space?
Olecranon is in which IC space?
Which muscle limits access to heart sounds and where does it extend from?
Triceps; caudal border of scapula to olecranon
*see previous notecards with IC spaces
Branches of the left subclavian a.
Branches of the right subclavian a.
-Branch supplying 1st few intercostal aa.
What is different about the subclavian branches in cattle?
Costocervical trunk gives rise to deep cervical and vertebral aa. on both the left and right side
The horse has which azygos vein?
Ruminants have which azygos vein?
Left OR both
Thymus growth and location in the horse
Largest at 2 mos. then regresses, little remains after 3 years; cranial mediastinum
Thymus growth in cattle
Both the cervical and thoracic portions grow rapidly in first 6-9 mos. then regress variably, thoracic portion may still be large in animals several yrs old
What is the significance of the proximity of the caudal mediastinal ln to the vagus n.?
They can compress the nerve; since the vagus innervates the esophagus and rumen, this can result in GI problems
Parasympathetic nn. branching from the vagus n.
Dorsal branches from left and right vagus (form dorsal vagal trunk)
Ventral branches from left and right vagus (form ventral vagal trunk)
Recurrent laryngeal n.
Where can the recurrent laryngeal n. be seen from the right and left sides?
Left - leaves vagus and courses around aortic arch
Right - courses around right subclavian a.
Sympathetic structures of the thorax
Sympathetic trunk and ganglion
Middle cervical ganglion
-ansa subclavia *connects cervicothoracic and middle cervical ganglia
Vertebral nn. - sympathetic contribution to cervical spinal nn.
Cardiac nn. are sympathetic or parasympathetic?
Which nn. make up the phrenic n.? Which m. does the phrenic cross?
C5, C6, C7; scalenus, then enters thoracic inlet
Which nn. make up the brachial plexus? Out of which m. do they emerge?
C6, C7, C8, T1, T2; scalenus
At what level does the trachea bifurcate in the horse? Is it dorsal or ventral to the esophagus?
T5 or T6; ventral to esophagus
At what level does the trachea bifurcate in cattle? At what level is the tracheal bronchus?
Which vessels provide functional supply to the lungs? Nutritional supply?
Functional - left and right pulmonary aa.
Nutritional - bronchoesophageal a.
Equine lung lobes
Left - cranial, caudal
Right - cranial, caudal, accessory
What are the cardiac notches and where are they located on each side?
Allow pericardium contact with chest wall, approximate division between cranial and caudal lobes
Left - ribs 3-6
Right - ribs 3-4
Ruminant lung lobes
Left - cranial (cranial part, caudal part), caudal
Right - cranial, middle, caudal, accessory
Where are the cardiac notches located on each side in ruminants?
Left - ribs 3-5
Right - ribs 3-4
The tracheal bronchus supplies which lobe (ruminants only)?
Right cranial lobe
The basal border of the lungs, which contacts the diaphragm, is located where in the horse?
Costochondral junction of 6th rib
Middle of 11th rib
Dorsal part of 16th rib
(6, 11, 16)
Borders of the lung field (auscultation triangle) in the horse
Cranial border - caudal aspect of triceps
Dorsal border - lateral edge of back mm.
Ventral border - basal border of lung (6, 11, 16)
What is different about the auscultation triangle in cattle?
The ventral border (basal border of the lung) is the 6th costochondral junction to the dorsal 11th rib (6, 11).
Potential space where costal and peripheral part of diaphragmatic pleura contact
Outpouching of pleura on medial side of right 1st rib, extending several cm. in the neck
Line of pleural reflection and location
Reflection of the costal pleura onto the diaphragm; costochondral junction of ribs 8-9, curves caudally and dorsally from costochondral junctions of succeeding ribs to vertebral end of rib 17
What is different about the line of pleural reflection in ruminants?
It starts at the 8th costochondral junction, to the mid 11th rib, and ends at rib 12
Site for thoracocentesis in the horse
7th IC space low
Site for thoracocentesis in the ruminant
6th or 7th IC space low
Where is the vertex (most cranial part) of the diaphragm located?
What goes through the aortic hiatus?
What goes through the esophageal hiatus?
What goes through the foramen venae cavae?
Caudal vena cava