Thoracic cavity Flashcards
(112 cards)
1
Q
The body cavity is divided into what 3 parts?
A
- Thoracic cavity
- Abdominal cavity
- Pelvic cavity
(abdom. + pelvic = abdominopelvic cavity)
- coelomic cavity (birds)
2
Q
The point of transition of the abdominal cavity into the pelvic cavity is called the:
A
abdominopelvic cavity
(there is no clear-cut demarcation between the two)
3
Q
The thoracic cavity lies within the ____ _____.
A
thoracic cage
4
Q
Where does the thoracic cavity begin and end?
A
beginning- cranial opening of the chest
end- thoracic outlet
5
Q
What is the section of the thoracic cavity cranial to the diaphragm?
A
The pectoral cavity
6
Q
What section of the thoracic cavity is caudal to the diaphragm?
A
The intrathoracic part of the abdominal cavity
7
Q
What 4 things make up the thoracic cavity?
A
- Bones
- Muscles
- Fascia
- Serosa
8
Q
What are the 3 bone parts of the thoracic cavity?
A
- Thoracic vertebrae
- Ribs
- Sternum
9
Q
What 3 things make up the cranial border of the thoracic cavity?
A
- 1st pair of ribs
- T1
- Manubrium (first sternibrae)
Serves as the thoracic inlet
10
Q
What makes up the caudal border of the thoracic cavity?
A
Diaphragm
- it is attached to the lumbar veterba, caudal ribs, and sternum
(NOT the last rib)
11
Q
What 2 things make up the dorsal border of the thoracic cavity?
A
- Hypaxial muscles
- Thoracic vertebrae
12
Q
What makes up the lateral borders of the thoracic cavity?
A
The ribs and intercostal muscles
(where most surgical procedures are conducted)
13
Q
What are the 4 openings into the diaphragm?
A
- Caval foramen/hiatus
- Aortic foramen/hiatus
- Esophageal hiatus
- Lumbocostal arch
14
Q
The caval foramen/hiatus is the passageway for the:
A
caudal vena cava
15
Q
The aortic foramen/hiatus is the passageway for what 3 things?
A
- aorta
- azygos vein
- thoracic duct
16
Q
The esophageal hiatus is the passageway for what 2 things?
A
- esophagus
- vagal trunks (vagus nn.)
17
Q
What passes through the lumbocostal arch?
A
- sympathetic trunk
- splanchnic nerve
18
Q
What is the most cranial part of the central tendon of the diaphragm?
A
the cupula/vertex
19
Q
What is the site of traumatic pericarditis?
A
the cupula/vertex of the diaphragm
20
Q
What is a clear sign regarding the diaphragm that an animal may possess asthma?
A
If it flattens too much during inspiration or appears concave. This can be observed through radiography.
21
Q
What are the crura of the diaphragm?
A
leg-like extensions of the diaphragm that are tendinous and attach to the lumbar vertebrae
22
Q
What are the 2 functions of the crura of the diaphragm?
A
- restriction of the movement of the diaphragm
- muscular contraction
23
Q
In a radiograph, right lateral views can be identified due to the diaphragmatic cruras being _____, and the heart apex is:
A
diaphragmatic cruras are parallel
heart apex is not in contact with the sternum
24
Q
In a radiograph, left lateral views can be identified due to the diaphragmatic cruras _____, and the heart apex is _____:
A
diaphragmatic cruras crossing each other
heart apex is a bit raised, and is not in contact with the sternum
25
During what phase of respiration is surgical incision preferred? Why?
During inspiration; there is decreased organ contact with the body wall
26
Each time the dome-shaped diaphragm contracts, it flattens, causing the thoracic cavity's caudal border to move ______.
caudally
27
What is the diaphragm innervated by?
Phrenic nerve: somatic sensory and motor fibers
28
What main 2 arteries pass through the diaphragm?
- musculophrenic a.
- pericardiacophrenic a.
(there are also others, but we aren't going to talk abt them)
29
Where does the phrenic nerve originate?
C5-C7 (sometimes C4)
30
What is eructation in ruminants?
- Also called belching
- reflex involving the rumen, reticulum, esophageal orifice, and esophagus.
- process for removing fermentation gases produced in the reticulo-rumen
31
What are the 3 smaller cavities within the thoracic cavity?
- Pleural cavity
- Mediastinum
- Pericardium cavity
32
The pleural cavity contains the _____.
lungs
33
The pleural cavity is formed by what 2 things?
- pleura (serous membrane)
- mesothelial cells (lining the cavity)
34
The parietal pleura is closest to the ____.
thoracic wall
35
What is the difference between the visceral and parietal pleura of the pleural cavity?
visceral pleura adheres to the lungs
parietal pleura lines the walls of the thoracic cavity
36
What is the space between the parietal pleura and visceral pleura?
the pleural space
37
What are the functions of the pleural space/ serous fluid?
- secrete fluid by serous membrane/pleura
- lubricate lungs
- suspends/fixates the lungs/heart within the thoracic cavity
38
What are the 4 layers of the heart?
- pericardium
- epicardium (visceral paricardium)
- myocardium
- endocardium
39
What is the pericardial space?
The space between the pericardium and epicardium that contains pericardial fluid
40
What is the serosa on the surface of the lung called?
The pulmonary (visceral) pleura
41
What is the serosa lining the walls of the thorax, including the mediastinum and diaphragm?
The parietal pleura
42
Double serous membranes have a ___ function.
supporting and stabilizing
43
What is a thoracocentesis?
## Footnote
also called: thoracentesis, pleural tap, needle decompression(?), thoracostomy
A procedure in which fluid is collected off of the thoracic cavity
## Footnote
Helps with the diagnosis of pneumothorax (air) or hydrothorax (fluid) and therapy
44
Where is the safest place to perform a thoracocentesis?
- costodiaphragmatic recess
- intercostal spaces 6-8, somewhere close to the costochondral junction can also be used
45
Describe how to insert the needle when performing a pleural tap:
Insert the needle on the cranial end of the ribs and parallel to the lungs to avoid hitting nerves/vessels which run along the caudal border with the bevel down
46
Where do you enter in a thoracentesis in cases of fluid removal (hydrothorax)?
ventral, cranial border of ribs
47
Where do you enter in a thoracentesis in cases of air removal (pneumothorax)?
dorsal
48
Why do you NEVER insert a needle along the CAUDAL border of the ribs?
There are too many nerves and blood vessels. During a thoracentesis, try to come as close to the cranial border as possible
49
The mediastinal recess is bordered cranially by the _____.
pericardium
50
The mediastinal recess is bordered caudally by the _____.
diaphragm
51
On the right side, the mediastinal recess is by the _____.
caudal vena cava & its mesentery
52
On the left side, the mediastinal recess is by the ______.
mediastinum
53
The costodiaphragmatic recess is between the:
pleura costalis and the pleura diaphragmatica
(This space is filled by the lungs during inspiration.)
54
Each pleura from the right and left sides ends cranially in a dome-shaped sac called the ______.
pleura cupula
(in carnivores and ruminants, this extends about 1-2 finger widths furthan cranially than the cranial thoracic aperture)
55
The space between the left and right layer of the pleura mediastinalis is called the ______.
mediastinum
56
What are the 3 parts of the mediastinum?
- cranial/precardial mediastinum
- middle/cardial mediastinum
- caudal/postcardial mediastinum
57
The cranial mediastinum begins at the:
cranial aperture of the thorax
(supply vessels and nerve tracts run through the cranial mediastinum from the thoracic cavity -> head + cranial limbs & cranial wall of the cavity)
58
The thoracic cavity contains organs and tissues that function in which 5 systems?
- respiratory
- cardiovascular
- nervous
- immune (thymus)
- digestive
59
What are the clinical applications for the thoracic cavity?
- diaphragmatic rupture
- diaphragmatic hernia
- prolapse
- percussion
60
What are a few effects of a rupture of the diaphragm? (can be a consequence of external trauma)
- Abdominal organs become displaced into the thoracic cavity, compromising lung function
- at the defect site, the intestine may become incarcerated & blood supply to displaced organs could be obstructed
61
A diaphragmatic hernia involves the translocation of ______ into the thorax through an area of weakness in the connective tissue components of the diaphragm.
abdominal contents into the thorax
(The peritoneum also enters the thoracic cavity.)
62
What are the signs of a diaphragmatic hernia?
labored breathing and exercise intolerance
63
Which section of the thoracic cavity is commonly associated with diaphragmatic hernias?
intrathoracic part of the abdominal cavity
64
When there is no hernial sac, yet there is still organ displacement, it is called a _____.
prolapse
65
What is cardiac dullness? Idk if this is correct
a triangular area of the front of the chest (determined by percussion); corresponds to the part of the heart not covered by the lungs
66
Where can the apex beat of the heart be heard in dogs?
left: 4th to 5th intercostal space (5th is optimal)
right: 4th to 5th intercostal space
67
Where can the apex beat of the heart be heard in ruminants?
left: 3rd to 5th intercostal space (4th is optimal)
nothing on the right side
68
Where can the apex beat of the heart be heard in horses?
left: 3rd to 6th intercostal space (5th is optimal)
right: 3rd to 4th intercostal space
69
What does absolute dullness correspond to?
The costomediastinal recess; important during percussion
70
Where does absolute dullness occur in dogs?
left: 4th to 6th intercostal space
right: 4th to 6th intercostal space
71
Where does absolute dullness occur in ruminants?
left: 3rd to 4th intercostal space
nothing on the right side
72
Where does absolute dullness occur in horses?
left: 3rd to 5th intercostal space
right: 3rd to 4th intercostal space
73
What is the maximum audibility of the heart valve sounds in dogs?
- left AV-valve: 5th Is
- aortic valve: 4th Is
- pulmonary valve: 3rd Is
- right AV-valve: 4th Is
| Is = intercostal space
74
What is the maximum audibility of the heart valve sounds in cattle?
- Left AV-valve: 4th Is
- Aortic valve: 4th Is
- Pulmonary valve: 3rd Is
- Right AV-valve: 4th Is
| Is = intercostal space
75
What is the maximum audibility of the heart valve sounds in horses?
- Left AV-valve: 5th Is
- Aortic valve: 4th Is
- Pulmonary valve: 3rd Is
- Right AV-valve: 4th Is
| Is = intercostal space
76
What is serosa?
The outer lining of organs and body cavities of the abdomen and chest, including the stomach.
(thin, transparent, and moist MM that provides a partition, fixation, and contains blood vessels and nerves)
| also called the serous membrane
77
What 7 structures do you have to cut through from outside to inside to reach the viscera of the thoracic cavity?
- skin
- latissimus dorsi
- external intercostal
- internal intercostal
- endothoracic fascia
- serosa
- organs
78
What makes a serosa moist?
The presence of mesothelium
79
What is serosa called in the thoracic cavity vs the abdominal cavity?
thoracic- pleura
abdominal- peritoneum
80
What are the general boundaries of the abdominal cavity?
diaphragm to the wings of the ilium
81
What are the general boundaries of the pelvic cavity?
Wings of ilium to ischium
82
How does the thoracic cavity communicate with the external environment?
through the nose
83
How does the abdominal cavity communicate with the external environment?
through the mouth and anus
84
How does the pelvic cavity communicate with the external environment?
through the vagina and urethra
85
What are the 2 characteristics of a visceral cavity?
- They accommodate visceral organs
- They communicate with the external environment
86
What serves as a landmark for the thoracic cavity?
the ribs
87
What 5 structures provide support for the thoracic cavity?
- thoracic vertebrae
- ribs
- sternum
- muscles
- serosa
88
What is the dome-shaped musculotendinous structure located in the thoracic cavity?
the diaphragm
89
How does the volume of the thoracic cavity change?
by movements of the diaphragm and ribs, which is important for respiration
90
How does the contraction of the diaphragm affect the volume/pressure of the thoracic cavity?
Each time the dome-shaped diaphragm contracts, it flattens, causing the thoracic cavity's caudal boundary to move caudally
91
During inspiration, the pressure of the thoracic cavity _____ and the volume _____.
pressure decreases; volume increases
92
During expiration, the pressure of the thoracic cavity _____ and the volume _____.
pressure increases; volume decreases
93
What arteries and veins supply and drain the diaphragm?
cranial and caudal phrenic artery/vein
94
What is another name for the visceral pleura of the pleural cavity?
Pulmonary pleura
95
What are the 4 different names of the parietal pleura?
- diaphragmatic
- costal
- mediastinal
- cervical
the name varies depending on the location
96
What is the costodiaphragmatic recess?
The point where the costal and diaphragmatic parietal pleura join
97
What is contained within the mediastinal recess?
The accessory lung lobe
98
What separates with parietal and visceral pleura?
pleural cavity/pleural space, which contains serous fluid secreted by the serosa of the pleura
99
What is the result of excess fluid in the pleural space?
Inhibition of respiration
100
What are plicae?
serous membranes that connect two organs together
101
What are examples of special areas where large hollow organs are directly connected to the body wall through CT adhesions?
rumen or caecum of horses
102
What are the 3 niches/spaces of the thoracic cavity?
- mediastinal recess
- costodiaphragmatic recess
- pleural cupula
103
What 12 structures are contained in the cranial mediastinum?
- subclavian artery and vein
- vagus nerve
- sympathetic trunk
- esophagus
- thoracic duct
- phrenic nerve
- brachiocephalic trunk
- thymus
- trachea
- cranial vena cava
- recurrent laryngeal nerve
- longus colli m.
104
What 14 structures are contained within the middle mediastinum?
- sympathetic trunk
- ascending aorta
- esophagus
- principal bronchus,
- brachiocephalic trunk
- thoracic duct
- right azygos vein
- right vagus nerve
- right phrenic nerve
- costocervical trunk
- vertebral arteries
- bicarotid trunk
- internal thoracic arteries and veins
- cranial vena cava
105
What 10 structures are contained within the caudal mediastinum?
- left sympathetic trunk
- thoracic aorta
- esophagus
- ventral vagal trunk
- left phrenic nerve
- thoracic duct
- dorsal vagal trunk
- caudal vena cava
- right phrenic nerve
- internal thoracic artery
106
What is the purpose of the pericardial cavity?
to allow the heart to beat freely
107
What are the names of the two layers of the pericardal cavity?
- parietal: pericardium
- visceral: epicardium
108
What happens in the event of excess pericardial fluid volume?
beating of the heart is inhibited
109
What is pneumothorax?
air in the thoracic cavity due to either an internal or external puncture wound
110
What are the signs of pneumothorax?
labored breathing and collapsed lung
111
What is hydrothorax?
fluid in the thoracic cavity caused by heart disease, renal failure, or liver cirrhosis
112
What is hemothorax?
Blood in the thoracic cavity caused by rupture of the great vessels within the thoracic cavity
