Exam 2 Flashcards
(85 cards)
``Lecture 14
The Equine and Bovine thorax
What are the boundaries of the horse’s thorax?
What muscles are lining the thorax?
Boundaries
Formula: C7 T18 L6 S5 Cd15-21
Cranial: 1st rib/cartilage, manubrium, T1
Caudal: Diaphragm
Latera: Ribs/cartilage and intercostal muscles
Dorsal: Thoracic vertebrae and longus colli m.
Ventral: Sternum, costal cartilage, transverse thoracic m.
Muscles lining the thorax
- Longus colli: Atlas to T6, flexor, hypaxial muscle.
- Diaphragm: main muscle of respiration
-Costal part: attaches to cartilages of ribs
-Sternal part: dorsal surface of xiphoid cartilage
-Lumbar part: right and left crura-lumbar vertebrae
Central tendon: inner part of diaphragm Tendons of origin of the crura (The crus of diaphragm (pl. crura), refers to one of two tendinous structures that extends below the diaphragm to the vertebral column. There is a right crus and a left crus, which together form a tether for muscular contraction. They take their name from their leg-shaped appearance – crus meaning leg in Latin.).
Contraction of diaphragm = expansion of thorax, which allows for inspiration
Relaxation of the diaphragm = recoil, expiration, cranially compresses thorax.
What are the openings of the Diaphragm?
Where does it extend to?
Openings
-Aortic hiatus: between the two cura. Where aorta, azygos veins and thoracic duct pass through.
-Esophageal hiatus: perforates the right crus near its junction with the central tendon
-Caval foramen (vena cava): courses through central tendon on the right side.
-Vagus nerve trunk: just ventral to esophagus
Extends to 6th intercostal space/6th rib in horse and Ox
Olecranon frequently found at 5th intercostal space
Diaphragm gives plenty or room for organs in the thoracic cavity (lungs), one of the theories as to why horses are so athletic
Locomotor respiratory Coupling
Horses take one breath per stride
Conditioning is important because they can’t change how many times they breathe per stride.
As they move at speed, the abdominal viscera moves and expands the thorax aiding inspiration
What are characteristic of the pleural cavity and thoracic cavity in horses?
What are the mediastinal contents?
Pleural cavity is separated by mediastinum
Parietal pleura: lines the thoracic cavity
-Mediastinal pleura: cranial, middle or pericardiac, and caudal
-Diaphragmatic pleura
-Costal pleura
Whatever happens in one side also happens on the other due to Mediastinum not being complete in the horse
Medialstinal contents
- Cranial
-Thymus (not seen in older horses)
-Cranial mediastinal lymph node
-Thoracic duct
-Left recurrent laryngeal nerve (branch of vagus): Long nerve predispose to injury or dysfunction. Paralysis of the left side of larynx “Roaring syndrome” sound during exercise
-Sympathetic trunk
-Esophagus
-Trachea
-Vagus nerve
-Left phrenic branch of vagus - Middle
-Tracheobronchial nerve - Caudal
-Caudal mediastinal lymph node: they are small in horses but larger in bovine
Pleural cavities
What/where is the Pleural cupula?
What are the clinical implications of injury to the pleural cupula?
Where are the lines of pleural reflection?
PROJECTION of the pleural space
The plural cupola is the cranial extent of the pleural cavity. Extends cranial to first rib, is larger on the right side.
Extends outside of the thorax
Air in pleura cupula = collapsed lungs
-Axilla injury penetration, SQ emphysema common, air expansion of SQ tissue
The pleural cavity contains only a scant amount of serous fluid.
Costomedialstinal recess ventral to lungs
Lines of Pleural reflection
Costodiaphragmatic recess place where draining penhose can be placed
Horse
-18th rib and 8th rib
Bovine
-13th rib and 8th rib
Abdomen what are the boundaries? Peritoneum, Greater and Lesser Omentum what do they connect?
-Cranial: diaphragm
-Caudal: pelvic inlet
-Dorsal: lumbar vertebrae, diaphragm, and sub lumbar muscles.
-Lateral: abdominal wall muscles and diaphragm
-Ventral: abdominal wall muscles, lines alba, prepubic tendon.
Sublumbar muscles
-Psoas minor: lumbar vertebrae to body of ilium
-Iliopsoas most important, flexor of the hip: Psoas major: lumbar vertebrae to lesser trochanter
-Iliacus: wing of ilium to lesser trochanter
-quadratus lumborum: transverse processes of lumbar vertebrae to wing of sacrum and ilium
Retroperitoneum
-Kidneys (except left kidney of ruminant)
-Adrenal glands
-Ureters for most of their length
-Vessels: aorta, caudal vena cava
Greater omentum
-Connects the greater curvature of the stomach and the initial part of the duodenum with the terminal part of the large colon and initial part of the small colon (which connects dorsally to body wall)
-Omental bursa: is the space between the layers of greater momentum that won’t see during colic surgery
Lesser omentum
-Connects the lesser curvature of the stomach and the first part of the duodenum with the liver.
-Hepatogastric ligament and hepatoduodenal ligament
Bovine Omentum
Different than equine
Lecture 15
Thorax, Lungs
What is the approximate lung capacity in horses?
Do horse lungs have lobation?
What does the hilus of the lung contain?
Which lung has a larger and deeper cardiac impression?
55 liters
No lobation, except accessory lobe of the right lung.
Right equine lung
-Cranial, caudal, accessory lobes
-Cardiac notch @ 3rd-4th intercostal spaces
-Caudal portion may get compressed by diaphragm
-Medialstinal view: Hilus (Bronchus, pulmonary artery, pulmonary vein, pulmonary nerves and lymphatics)
Right lung mediastinal view
-Cardiac impression
-Cranial lobe
-Accessory lobe
-Caudal lobe
-Impression of caudal vena cava
-Impression of cranial vena cava
-Azygous vein impression
-Aortic impression
-Esophageal impression
Right lung lateral view
-Dorsal border
-Basal Border
-Caudal lobe
-Cardiac notch
-Cranial lobe
Right lung medial view
-Pulmonary vein, artery, principal bronchus, pulmonary ligament, etc.
Caudal Diaphragmatic view
-Caudal lobe left and right lungs
-Impression of caudal vena cava
Left Equine Lung
Lateral costal view
-Cranial and caudal lobes
-Deep cardiac notch 3rd to 6th intercostal spaces
-Pericardium contact the thoracic wall at 3rd and 6th ribs
Medial view left lung (mediastinal)
-Hilus
-No accessory lobe
-Esophageal impression
-Aortic impression
-Vascular impression
-Cardiac impression (larger)
Lateral view
-Dorsal border
-Basal Border
-Caudal lobe
-Cardiac notch
-Cranial lobe
At what vertebrae numbers can you find the lungs carina?
Which is the primary (main) bronchus (left and right)?
Which is the Secondary bronchus (lobar bronchus)?
Tertiary (segmental) bronchus (3 caudal, cranial and accessory for Rt and cranial and caudal for left lung)?
Subsegmental bronchus?
Bronchioles?
Between T4-T5
Carina is the very last place where you find the trachea cartilage
It bifurcates to left and right bronchi
Where is the Basal border of the lung in a horse?
Where is the costodiaphragmatic recess (pleural recess) costsmediastinal recess?
How much is the border of the lungs separated from the line of pleural reflection?
Basal border of the lung:
- Dorsal region of Rib 16th to Rib 6th
-Middle of the 11th Rib
-Costochondral junction of the 6th rib (just caudal to olecranon)
Pleural Recesses
-Costomediastinal recess: space ventral to the lungs
-Costodiaphragmatic recess: space caudal to the basal border of the lungs
The basal border of the lungs is separated from the line of pleural reflection by approximately
What are the landmarks for Auscultation of the lungs in Horses?
How much does an equine heat weigh on average?
Caudal angle of scapula
Upper end of the 17th rib
Point of the elbow
Long head of triceps m.
Heart
-0.7% of total body weight
-Average pulse: 28-45 bpm in a mature horse, but it can reach more than 250 bpm during maximum exertion
Which is the auricular face and atrial face?
What can we find on the left and right view of the heart?
Left view auricular face
-Brachiocephalic trunk (cranially)
-Aorta (caudally)
-Pulmonary trunk ligamentum arteriosum
-Pulmonary valve (tricuspid)
-Pulmonary arteries
-Cranial vena cava
-Right auricle
-Right Atrium
-Right ventricle (opened = Conus arteriosus)
-Paraconal inter ventricular branch and Great cardiac vein (apex area)
-Left ventricle
-Left ventricle opened = papillary mm, chordae tendinaeae, Left atrioventricular valve (mitral)
-Left atrium
-Caudal vena cava
-Circumflex branch
-Pulmonary veins
Right view ventricular face
-Right Azygous vein
-Aorta
-Brachiocephalic trunk
-Cranial vena cava
-Right circumflex branch
-Right atrium
-Right atrioventricular valve
-Right ventricle
-Right papillary mm.
Trabecula septotmarginalis
-Subsinuosal inter ventricular brach and middle cardiac vein
-Left ventricle
-Circumflex branch and Great cardiac vein
-Caudal vena cava
-Inside caudal vena cava = coronary sinus, Fossa ovalis intravenous tubercle.
-Pulmonary veins
-Pulmonary arteries
Coronary circulation in the horse, left and right
Equine Heart: Points of maximal intensity
Left coronary artery
-Paraconal inter ventricular branch and great cardiac vein
-Circumflex branch and coronary sinus vein
Right Coronary artery
-Right circumflex branch and coronary sinus vein
-Subsinuosal inter ventricular branch and middle cardiac vein
Pulmonary Valve: left side, 3-4th intercostal space craniodorsal to the olecranon
Aortic valve: left side, 4th intercostal space, ventral to the shoulder joint
Left AV valve (mitral): left side, 5th intercostal space, caudodorsal to the olecranon
Right AV valve (tricuspid): right side, 4th intercostal space, caudodorsal to the olecranon.
Branching of the aortic arch
-Brachicephalic trunk (Huge in horses compared to dogs)
-Left subclavian a.
-Costocervical trunk a. (branch of subclavian a. )
-Deep cervical a. (branch of subclavian a. )
-Right subclavian a.
-Bicarotid truck a. ; Rt and Lt common carotid aa.
Branches of Subclavian a.
Deep cervical a. supplies what important structure?
Deep cervical a., Deep costocervical a. Nuchal ligament injection can lead to hematoma in foals
-From costocervical trunk on the right side, subclavian a. on the left side.
-Courses toward the head to supply cervical structures and musculature in the caudal neck region
Vertebral artery
What does it give rise to and supply?
-Courses cranially through transverse foramina of the cervical vertebrae
-Gives rise to spinal and muscular branches
-Courses through the alar foramen and lateral vertebral foramen of the atlas and enters the vertebral canal.
-Right and left vertebral aa. from basilar a. (horse)
Superficial cervical a.
Internal thoracic a.
Superficial cervical a.
-Supplies structures in the craniolateral shoulder region
Internal thoracic a.
-Ventral intercostal aa.
-supplies ventral part of the thoracic wall
Cranial epigastric a.
-supplies the ventral abdominal wall
Name the arteries
Left subclavian a.
Costocervical trunk a.
Deep cervical a.
Vertebral a.
Superficial cervical a.
Axillary a.
Internal thoracic a.
Horse main/clinical significant veins
Cranial vena cava
Subclavian vein
Bijugular trunk
External jugular veins
Right side
Cranial vena cava
Superficial cervical vein
Vertebral vein
Costocervical vein
Right Azygous vein
Caudal vena cava
General viceral Efferent Sympathetic Mediastinum
-Cervicothoracic ganglion
-Vertebral n.
-Ansa ssubclavia
-Vago sympathetic trunk
-Middle cervical ganglion
-Rami communicantes
-Sympathetic trunk
-Major Splanchnic n.
General visceral Parasympathetic Mediastinum
-Vago sympathetic trunk
-Recurrent laryngeal n.
Vagus n.
Recurrent laryngeal n.
-Dorsal vagal branch
-Ventral vagal branch
-Dorsal vagal trunk
-Ventral vagal trunk
Lecture 16 Ruminant Heart and Lung