Block 3 Flashcards
(199 cards)
1
Q
What are the three meninges?
A
Dura mater, Arachnoid, Pia
2
Q
What is the location of CSF absorption into the venous system?
A
Dural sinuses
3
Q
The dura mater is a thick layer of ___________
A
Thick layer of fibroblasts
4
Q
What meninx is spiderweb-like and consists of a thin layer of fibroblasts that trap CSF between it and pia mater?
A
Arachnoid mater
5
Q
What meninx consists of a single layer of fibroblasts?
A
Pia mater
6
Q
What is the primary function of the meninges?
A
To protect the brain and spinal cord from mechanical injury
7
Q
The flow of CSF enters what location after it passes through the cerebral aqueduct?
A
The Fourth Ventricle
8
Q
Where does the CSF enter after the lateral ventricles?
A
The third ventricle, through the foramina of Monro (interventricular foramina)
9
Q
Where is CSF formed?
A
Ependymal cells in choroid plexus, located in each of the 4 ventricles
10
Q
List the 4 functions of CSF
A
1) Cushion brain
2) Maintain extracellular environment for neurons and glia cells
3) Waste control
4) Distribution medium for peptide hormones and growth factors that are secreted into CSF
11
Q
If there is increased CSF in the skull and associated increased ventricular volume and intracranial pressure, what is the most likely cause?
A
Hydrocephalus
12
Q
This is normally caused by an obstruction to CSF flow
A
Non-communicating hydrocephalus
13
Q
What type of hydrocephalus is caused by impairment of absorption and can be secondary to meningitis or hemorrhage?
A
Communicating hydrocephalus
14
Q
What are the blood-brain barrier components?
A
Specialized endothelial cells lined by basal lamina, astrocyte endfeet, pericytes and microglial cells
15
Q
What is the importance of a functioning blood brain barrier?
A
To repel potentially harmful substances
16
Q
What meninx fuses with the inner surface of the skull bones?
A
Dura mater
17
Q
What ventricle is found between the two cerebral hemispheres?
A
Lateral ventricles
18
Q
What ventricle is found at the midline of the diencephalon?
A
Third ventricle
19
Q
What ventricle is located between the cerebellum and the dorsal surface of the hindbrain (pons/medulla)?
A
Fourth ventricle
20
Q
Explain the flow of CSF down the pressure gradient from its site of formation at the choroid plexus
A
Lateral ventricles into the 3rd ventricle, through the foramina of Monro, through the cerebral aqueduct of the midbrain, into the fourth ventricle into the subarachnoid space through the foramina of Luschka
21
Q
Where is CSF sampled from in most veterinary species?
A
Between skull and first cervical vertebra (atlas)
22
Q
If the CSF fluid appears turbid, what does that indicate?
A
Increased cellularity (poss. infection, cancer)
23
Q
Absorption of CSF tends to be pressure dependent and _________
A
Unidirectional
24
Q
True or False
CSF fluid does not get replaced in the body
A
False - it is replaced several times a day
25
In brain capillaries, passage through intercellular clefts is blocked by what?
Tight junctions
26
True or False
Exchange of blood solutes is highly selective in the blood-brain-barrier
True
27
What surrounds the endothelium in the blood-brain-barrier?
Pericytes and astrocytes
28
What kind of junctions are found in the blood brain barrier?
Tight junctions
29
True or False
Pinocytosis is commonly seen at the blood brain barrier
False
30
What types of molecules can easily pass across the capillary endothelium of the blood brain barrier?
Small, uncharged, lipid soluble and unbound to proteins (ie. O2, CO2, ethanol, nicotine)
31
What are some examples of molecules that need specific, carrier-mediated transport mechanisms to pass through the blood brain barrier?
Glucose and some amino acids
32
True or False
Antibiotics and anti parasitic drugs readily pass the blood brain barrier
False - the BBB repels them
33
What nerve block is used to prevent closure of the eyelid/blinking?
Auriculopalpebral nerve block
34
What kind of nerve block would you use to perform an ophthalmic exam?
Auriculopalpebral nerve block
35
What are the landmarks for the auriculopalpebral nerve block?
Dorsal aspect of the zygomatic arch, or depression caudal to the mandible
36
This type of block is only a motor block and does NOT desensitize the eye
Auriculopalpebral nerve block
37
True or false
The motor nerve can be palpated
True
38
True or False
If you are going to enucleate the eye, you do not need to block all 4 nerves
FALSE - all 4 must be blocked
39
What are the main sensory nerves of the equine eye?
A) Supraborbital nerve
B) Lacrimal Nerve
C) Infratrochlear nerve
D) Zyomatic nerve
ALL
40
What sensory nerves do you block with a SQ injection?
Lacrimal, infratrochlear, and zygomatic
41
True or False
You have to fully anesthetize a horse to enucleate the eye
False - Standing enucleation by blocking all 4 sensory nerves plus the retrobulbar nerve
42
What dental nerve block works to block everything rostral on one side of the face?
Infraorbital nerve block
43
This nerve block desensitizes the ipsilateral upper lip and nose
Infraorbital nerve block
44
If you need to desensitize teeth rostral to the 1st molar, maxillary sinus and roof of nasal cavity, what block is used?
Infraorbital nerve block
45
What block is used to desensitize the lower lip and lower incisors?
Mental Nerve Block
46
What block provides anesthesia of the mandible?
Inferior alveolar nerve block
47
This nerve block is often performed blindly (which is difficult and possibly risky) however, it is still safer than GA
Inferior alveolar nerve block
48
What dental block is used for the maxilla and sinus cavity?
Maxillary nerve block
49
Where is the caudal epidural administered?
Between Co1 and Co2 space
50
What nerve block is administered in the space palpated by moving tail up and down in a horse?
Caudal epidural
51
What are some techniques that can be used to verify placement of caudal epidural?
Loss of resistance/hanging drop technique (checking placement by placing a drop of the block in the hub of the needle)
52
What are some indications for an equine epidural (caudal epidural)?
Tail, perineum, rectum or vulva procedures
Fetotomy, obstetric manipulations
Hindlimb analgesia
53
For local anesthetics, what is important to limit the cranial spread of the drug?
Volume
54
True or False
The goal of local anesthetics in equine is to cause motor blockage of the hindlimbs
FALSE
We are avoiding hind limb ataxia/motor blockage
55
How much 2% lidocaine is typically used in an adult horse?
6-8 mL
56
Xylazine and detomidine are what type of drugs?
Alpha-2 agonists
57
What are some side effects of alpha-2 agonists?
Sedation, 2nd degree AV block, ataxia
58
True or false
Side effects of alpha 2 agonists can be reversed
True (w/ IV antagonist)
59
What drug provides analgesia without the risk of motor blockade?
Morphine
60
What drug is typically used for hind limb trauma, surgery or severe laminitis?
Morphine
61
What are some common side effects of morphine?
Uticaria and ileus
62
This analgesic can be administered via epidermal catheter for long-term analgesia
Morphine
63
True or False
An epidural catheter can be placed to administer local anesthetics in equine
FALSE
Local anesthetics can not be administered epidurally due to loss of motor
64
If the epidural catheter is advanced into the LS space what happens?
analgesia for the hindlimbs
65
What combination provides excellent analgesia for equine?
Alpha 2 agonist + Morphine
66
What is used for additional anesthesia in large animals for castration?
Intratesticular block
67
True or False
If an intratesticular block is used, the animal does not need sedation or GA
False
68
Why is lidocaine used for intratesticular blocks?
Rapid onset - quickly diffuses into spermatic cord
69
How much lidocaine can be used in horses for intratesticular blocks?
20 mLs
70
How much lidocaine can be used in small ruminants for intratesticular blocks?
2-5mL
71
What block should only be used for ruminant enucleation and why?
Retrobulbar block - only used for enucleations because you can perforate the eye
72
What nerve is blocked for dehorning purposes?
Cornual branch of zygomaticotemporal nerve
73
What type of block is commonly performed for goat dehorning?
Ring block around the horn
74
What nerve can not be realistically blocked in goats?
Cornual branch of infratrochlear nerve (it is too close to the eye)
75
If a laparotomy needed to be performed on a cow, which of the following blocks could be used?
a) Auriculopalpebral
b) Infraorbital
c) Line block
d) Inverted L block
e) caudal epidrual
C and D (Line and inverted L)
76
What are the sites of administration for an L block?
T13, L1, L2
77
What layers is a line block providing analgesia for?
SQ and muscular layers
78
In what block (Inverted L or Line) is the local being injected along the incision site?
Line block
79
What blocks, used for ruminant flank laparotomy, are given in the dorsal and ventral branches of T13, L1 and L2?
Proximal paravertebral block
Distal paravertebral block
80
Inclusion of what injection site would provide better anesthesia for a flank laparotomy?
a) T12
b) L3 and L4
c) L3
d) None- you want to stay away from L3 and L4
b) L3 included for proximal block, L4 included for distal block
81
What is a contraindication of including L3 in a block?
If L3 and L4 are administered local block, the animal could lose motor and go down which is dangerous
82
What are some indications for a caudal epidermal in ruminants?
Obstetric manipulations, surgical procedures for tail, perineum, anus, rectum, vulva, vagina, prepuce, scrotum
83
Where is a ruminal caudal epidermal administered?
Between S5-Co1 or Co1-Co2 space
84
What types of drugs are used for ruminant caudal epidurals?
Local anesthetics, alpha 2 agonists, moprhine
85
True or False
Ruminant caudal epidurals are rarely performed
False - common and easily performed
86
True or False
Ruminant lumbosacral epidural should not induce loss of motor function
False - it does induce motor function
87
Where is the site of injection for the ruminant lumbosacral epidural?
Between L6-S1
88
What animals is the ruminant lumbosacral epidural used?
Immature cattle (caudal epidural in adult cattle), small ruminants, camelids, and pigs
89
What are the 4 techniques used for anesthesia for the teats?
Ring block
Inverted V
Cistern infusion
IV regional anesthesia
90
Paravertebral block of L1-L3 (L4) can provide anesthesia to what area of the udder?
Cranial aspect of udder and teats
91
What block provides anesthesia to the caudal aspect of the teats and udder (around anus)?
Pudendal block
92
Intravenous regional anesthesia (Bier Block), is used for what?
Commonly used for site of injury or disease (ie foot abscess/wound)
93
Why would a Bier Block be given IV versus as a local block?
Inflammation can block the effects of a local block
94
What side of the heart pumps blood through the lungs?
Right side of the heart
95
What side of the heart pumps blood through the body's tissue and supplies O2 and nutrients, removing CO2?
Left side of the heart (Systemic)
96
Contraction and emptying of the heart
Systole
97
Relaxation and filling of the heart
Diastole
98
What is the primary function of the cardiovascular system?
Transport
99
Most of the resistance in blood vessels is due to what?
Vessel diameter
100
Ability to increase the volume of blood held without a large increase in blood pressure
Capacitance
101
What does high capacitance allow for?
High blood volume and low blood pressure; it is the ability to increase the volume of blood without a large increase in BP.
102
True or False
The greater the vessel diameter, the greater its resistance and blood flow.
False: The greater the vessel diameter, the great its resistance and LOWER the blood flow
103
What holds more volume of blood, a vein or artery?
Veins hold more volume
104
What tolerates higher pressure, a vein or artery?
Artery
105
What is the largest artery?
Aorta
106
Arteries deliver _______ blood to the organs.
Oxygenated
107
Smallest branches of arteries
Arterioles
108
What blood vessels have the highest resistance to blood flow?
Arterioles
109
Thin walled, single layer of endothelial cells surrounded by basal lamina, also the site of exchange of nutrients, gases, water and solutes between blood and tissues.
Capillaries
110
Thick walled blood vessels that are under high pressure
Arteries
111
Thin walled blood vessels with low elastic tissue but high capacity, containing the largest percentage of blood in the CV system.
Venules and veins
112
What blood vessels would have the largest lumen?
Veins
113
What cells make up the atria and ventricles, are able to shorten/lengthen, and have striated muscles specialized for contraction and impulse conduction?
Working myocardial cells (cardiomyocytes/myocardium)
114
Cells that exhibit automatic rhythmical electrical discharge (cardiac action potentials)
Pacemaker Cells (autorhythmic cells)
115
Where are pacemaker cells found?
SA and AV nodes, Purkinje fibers
116
Found in the conducting system of the heart, these cells carry the action potential throughout the heart
Conducting cardiomyocytes
117
What are the similarities between cardiac and skeletal muscles?
Fibers are striated
Myofibrils of actin and myosin
Similar sarcomere arrangement
Contain SR and T-Tubules
118
True or False
Cardiac muscle is usually multinucleated
False - It is uninucleated
119
What type of muscle has high mitochondrial density?
Cardiac muscle
120
What allow the cardiac muscle cells to contract in a wave-like pattern?
Intercalated discs
121
True or False
Cardiac muscle fuse into a single multinucleated fiber during embryonic development
False - it is a functial syncytium
122
True or False
Cardiac myocytes branch during development and bind to other myocytes
True
123
True or False
Fibers remain separated as distinct cells with their sarcolemma, but are also electrically separate to each other.
False - they are electrically CONNECTED to each other through intercalated discs (the rest of the above statement is true)
124
Part of the sarcolemma, contains 2 cell-cell junctions (Gap junctions and desmosomes)
Intercalated disk
125
Provide mechanical strength and anchor the end of the cardiac muscle fibers together
Desmosomes
126
What is the normal/primary/natural pacemaker of the heart?
SA node or sinus node
127
Where is the SA node located?
Right atrium
128
Where are slower pacemakers located?
AV node and Bundle of His-Purkinje system
129
Small strip of specialized cardiac muscle cells (pacemaker cells)
Sinus node (SA node)
130
True or False
The SA nodes have numerous contractile muscle filaments
False - they have almost none
131
What is the movement of the action potential (from where to where)?
SA node --> Atrial walls --> AV node
132
What delays impulse conduction from the atria to the ventricles?
AV node
133
Located in the posterior wall of the right atrium, immediately behind the tricuspid valve
AV node
134
AV node fibers have fewer GAP junctions for what reason?
Slower ion movement between cells, which allow the atria to empty their blood into the ventricles before ventricular contraction begins
135
AV-Bundle passes downward in the ventricular septum and divides into left and right bundle branches that are found where?
Beneath the endocardium
136
The AV-Bundle allows only forward conduction from what to what?
From the atria to the ventricles
137
Atria muscle is separated from ventricular muscle by what?
continuous fibrous skeleton
138
True or False
The transmission velocity in the ventricular purkinje system is fast
True
139
Special purkinje fibers lead the AV node impulses through the what into the what?
Through the AV-Bundle (bundle of His) into the ventricles
140
The ends of Purkinje fibers penetrate the muscle mass and become continuous with what?
Cardiac fibers
141
Part of the heart that is oriented dorsocranially
Base
142
Part of the heart that points ventrocaudally and to the left
Apex
143
What view of the heart is called the auricular surface?
The left view
144
What view of the heart is called the atrial surface?
The right view
145
Separation of the atria and ventricles, often containing fat and encircles the base of the heart
Coronary groove
146
Separation of the ventricles
Interventricular grooves
147
AV valve cusps/leaflets that originate from the outer ventricular wall
Marginal or Parietal cusps
148
AV valve cusps/leaflets that originates from the interventricular septal wall
Septal cusps
149
What anchor cusps to the inner walls of the ventricles?
Chordae tendineae
150
What secure the chardae tendineae to the inner walls of the ventricles?
Papillary muscles
151
What closes during systole to prevent backflow of blood into the atria?
AV valves
152
What side of the heart receives deoxygenated blood from systemic cirulation and send blood into pulmonary circulation?
The right side
153
What side of the heart receives oxygenated blood from the pulmonary circulation and send blood into the systemic circulation
Left side
154
The right atrium receives blood from what?
The cranial and caudal vena cava (and venous return from the heart muscle)
155
The right ______ pumps blood into the right _________ through the right _______ _________
The right **atrium** pumps blood into the right **ventricle** through the right **AV valve**
156
Right ______ contracts to send blood to the lungs through the __________ trunk & _________ arteries
The right ventricle contracts to send blood to the lungs through the pulmonary trunk and pulmonary arteries
157
The ________ semilunar valve prevents backflow of blood from the pulmonary trunk into the right ventricle during _______
The pulomonary semilunar valve prevents backflow of blood from the pulmonary trunk into the right ventricle during diastole
158
Oxygenated blood travels back to the heart through the _______ veins into the left ______ which then pumps blood into the left ______ through the left _____ ______
Oxygenated blood travels back to the heart through the pulmonary veins into the left **atrium** which then pumps blood into the left ventricle through the left **AV valve (mitral valve)**
159
Left ventricle contracts to send blood through the _____ ______ valve and into the ________ out to the rest of the body (and to supply the heart muscle itself)
Left ventricle contracts to send blood through the **aortic semilunar**valve and into the** aorta**out to the rest of the body
160
The _____ _____ valve prevents backflow of blood from the aorta into the left ventricle during ______
The **aortic semilunar **valve prevents backflow of blood from the aorta into the left ventricle during **diastole**.
161
Valve located between the right ventricle and pulmonary arteries (trunk)
Pulmonary Semilunar Valve
162
Valve located between the left ventricle and the aorta
Aortic Semilunar Valve
163
If you are auscultating the left side of a dog, what are the three valve sounds you may listen for and where specifically are they?
P = pulmonary valve (3rd IC space)
A = Aortic valve (4th IC space)
M = Mitral (left AV) (5th IC space)
164
If you are auscultating the right side of a dog, what valve are you listening for and where is it located?
The tricupsid/Right AV (4th IC space)
165
What sound are you hearing at the beginning of systole that is the "lubb" sound?
S1
166
What sound are you hearing that is the "dupp" sound?
S2
167
The closure of the left and right AV valves produces what sound?
The S1 or "lubb"
168
The closure of the aortic and pulmonic semilunar valves produce what sound?
The S2 or "dupp"
169
True or False
You should be able to hear the sound of blood flow from one structure to the next in normal dogs and cats?
False - blood flow from one structure to another is normally silent in normal dogs and cats
170
What sounds are not normally heard in normal small animals, but can be heard in some large animals normally?
S3 and S4
171
What is an example of a cause of an ABNORMAL S3 sound?
Congestive heart disease / DCM
172
What is an example of a cause of an ABNORMAL S4 sound?
Hypertrophic Cardiomyopathy (HCM)
173
Where is the thymus located?
In the cervicothoracic area, starting from dorsal sternal aspect towards ventral cervical area (sometimes more thorax vs cervical depending on species)
174
Less discrete lymphoid aggregations
Tonsils
175
This lymphatic organ is placed at the level of the abdominal cavity in relationship with the stomach. It has importance in storage, release, and concentration of erythrocytes and produces lymphocytes and monocytes
Spleen
176
Found in the course of blood vessels, these small lymphatic bodies resemble lymph nodes but have no lymphatic vessels (absent afferent/efferent lymphatics).
Hemal nodes
177
True or False
All animals have hemal nodes
False
178
In what species are hemal nodes typically found?
Sheep
179
These structures may represent an intermediate stage between a lymph node and the spleen
Hemal node
180
Found in some animals in relation to their abdominal and thoracic viscera
Hemal node
181
Present in many mucous membranes (larynx, intestine, prepuce, and vagina) and do NOT have capsules
Diffuse lymphatic tissue and lymphatic nodules
182
In what lymph tissue are capsules present?
Lymphatic organs
183
What are the lymphatic organs?
Lymph nodes, spleen, thymus gland
184
What lymph tissue is found in connective tissue of almost all organs?
Diffuse lymphatic tissue
185
What lymph tissue is found singly or in clusters?
Lymphatic nodules
186
What are the lymphatic nodules that occur in the mucosa that lines the ileum?
Peyer's patches
187
What is the role of the lymphatic circulatory system?
Collects interstitial fluid, waste material, and others (like viruses and bacteria) that are in the body tissues outside the bloodstream
188
What is lymph?
Ultrafiltration of blood plasma
189
What is the difference between lymph and blood plasma?
Lymph has less protein as it is ultra-filtered
190
Lymph vessels draw up the lymph fluid from around the cells to send it towards the _______. There, lymph fluid collects into a large vessel that drains into the ______ ____ ____ that opens in the heart.
Chest, cranial vena cava
191
Without the lymph vessel, what would happen to lymph fluid?
It would build up and cause swelling
192
Contain immune cells that help fight infection by attacking and destroying germs that are carried through the lymph fluid
Lymph nodes
193
What vessels lead into a lymph node?
Afferent lymphatic vessels
194
What vessels lead out of a lymph node?
Efferent lymphatic vessels
195
True or False
Afferent vessels become Efferent vessels
False
Efferent vessels become afferent vessels
196
What are the lymph nodes of the head?
Parotid, lateral retropharyngeal, and mandibular
197
What are the lymph nodes found in the neck?
Superficial cervical (pre-scapular)
198
Lymph node situated caudo-ventrally to the angle of the mandible, in the angle between the masseter muscle and mandibular salivary gland
Mandibular lymph center
199
Usually a single lymph node, situated near the base of the ear, close to the tempo-mandibular joint
Parotidian lymph center
