Week 2 Flashcards

1
Q

In what 8 scenarios should a check x-ray be requested?

A
  1. Shortness of breath
  2. Acute chest pain
  3. Investigation for malignancy
  4. Following severe trauma
  5. Pneumonia
  6. Chronic lung diseases
  7. Pleural diseases
  8. Peritonitis
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2
Q

What is the lingula?

A

A combined term for the two lingular bronchopulmonary segments of the left UPPER lobe.
Made up of: Inferior lingular segment, superior lingular segment

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3
Q

What is the process for interpreting a chest XR?

A
  1. Admin and Technical (PD PO RIP)
    - Patient id
    - Date
    - Projection: PA/AP
    - Orientation: L or R
    - Rotation
    - Inspiration: Full inspiration detected by rib count (10 from back, 6 from front)
    - Penetration: Exposure so that vertebral bodies just visible behind back
  2. Structures (ABCDEFGH):
    - Airway: Trachea, Bifurcation of bronchi visible
    - Breathing: Check expansion of lungs, check lung fields, opacities
    - Cardiac: Heart size, borders of heart
    - Diaphragm: Right hemidiaphragm 1 rib higher than left, identify stomach bubble, look for free air below right diaphragm
    - External structures: Surrounding bones
    - Fat and soft tissues: Breast shadows, examine subcutaneous fat
    - Great vessels: Aortic arch, pulmonary arteries, veins in the mediastinum, calcium deposits
    - Hidden areas: Apices, mediastinum widening, aortic dissection, mediastinal emphysema, behind the heart for lingular pneumonia
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4
Q

What is the carina?

A

The ridge of cartilage of the trachea at the bifurcation

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5
Q

What is possible reason for a missing rib from a CXR?

A

Tumour grown around the rib. If the CXR is PA thent he tumour is posterior to rib

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6
Q

What are the review areas of the CXR?

A

Apices
Behind the heart
Below the diaphragm (Space between liver = gas)

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7
Q

What are the 4 areas of error that can occur when taking a CXR?

A

PA vs AP Film: PA preferred as the magnification of heart is reduced = film more reliable
Rotation: For optimum rotation, there must be an equal distance between the medial ends of the clavicle and the spinous processes of the vertebrae
Penetration: Over-penetration appears dark, Poorly penetrated appears light/fuzzy
Inspiration vs Expiration: Inspiration preferred as structures more densely packing into thorax

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8
Q

What are the two major types of solid structures in the interstitial fluid?

A

Collagen

Proteoglycans filaments

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9
Q

What substances generates the Colloid Osmotic/Oncotic Pressure?

A

Plasma proteins (mainly albumin)

This creates a difference in the abundance (and consequently pressures) between capillaries and extracellular fluid

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10
Q

Which is lower, the plasma or interstitial osmotic pressure?

A

Interstitial

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11
Q

What is the capillary hydrostatic pressure and what does it cause fluid to do?

A

Pressure difference between either end of the capillary
Forces fluid out of capillary into the interstitium
Drops from arterial to venous end

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12
Q

What is interstitial hydrostatic pressure and what effect does it have on fluid?

A

Pressure within the interstitial fluid.
When positive= forces fluid into the capillary
When negative= Draws fluid into the interstitium

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13
Q

What 4 features is the lympathetic system in control of?

A
  1. Concentration of proteins in interstitial fluids
  2. Volume of interstitial fluid
  3. Interstitial pressure
  4. Immune response
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14
Q

Venous return is a major determinant of…

A

Cardiac output due to myogenic response of the ventricles

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15
Q

Factors affecting venous return?

A
  1. Sympathetic innervation: Increases tone, hence decrease capacity of vein, more blood flow to heart. Hence increase in CO
  2. Muscle Pumps: Muscle relaxed= Valve closed, blood in vein. Muscle contracted= Valve open, blood flow to heart
  3. Postural effects: Equal pressure when recumbent, when standing drop in head and increase in legs.
  4. Inspiratory movements Leads to pressure difference between peripheral veins and heart as thorax pressure decreases
  5. Blood volume
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16
Q

What is orthostatic (postural) hypotension?

A

Decrease in bp when going from supine to upright.

Reflex vasoconstriction in legs and lower abdomen

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17
Q

What are the boundaries of the anterior mediastinum?

A

Anterior: Sternum
Posterior: Pericardium
Lateral: Lungs + pleura

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18
Q

What are the boundaries of the superior mediastinum?

A
Superior: Thoracic inlet
Inferior: Sternal angle at T4/5
Anterior: Manubrium
Posterior: T1-4
Lateral: Lungs + pleura
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19
Q
Thymus:
Structure?
Location?
Function?
Arterial supply?
Venous drainage?
A

Structure: Bi-lobed
Location: In anterior mediastinum between manubrium, sternum and pericardium. Extends from jugular notch to 4th CC
Function: Programming t-lymphocytes, recognizing self antigens
Arterial supply: Internal thoracic and inferior thyroid arteries
Venous drainage: Left brachiocephalic vein

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20
Q

Name the 5 bony landmarks of the venous plane of the superior mediastinum?

A
  1. Post. to sternoclavicular joint: Internal jugular and subclavian veins join to form right and left BCVs
  2. Post to manubrium: Left BCV passes anterior to arch of aorta
  3. Post to 1st R costal cartilage: RBCV and LBCV join to form SVC
  4. Post to 2nd R costal cartilage: Arch of azygos vein joins SVC
  5. Post. to 3rd costal cartilage: SVC enters right atrium
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21
Q

What areas do the following veins drain:

  1. Azygos
  2. Subclavian
  3. Internal jugular
A
  1. Azygos: Posterior chest wall
  2. Subclavian: Upper limb
  3. Internal jugular: Head and neck

All drain to their corresponding BCV

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22
Q

What two veins drain into the LBCV and not the right?

A
  1. Internal thoracic: Drains ant. chest wall

2. Thyroid veins: If protruding above manubrium, could be at risk in tracheostomy

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23
Q

What are the three branches of the aortic arch?

A
  1. Brachiocephalic trunk (gives RCC, RSV arteries)
  2. Left common carotid
  3. Left subclavian
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24
Q

What two arteries “clasp” the trachea?

A

Left common carotid

Brachiocephalic trunk

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25
What is the trachea made up of?
C-shaped rings of hyaline cartilage supporting a fibro-elastic and muscular air-transport tube
26
How does the right main bronchus differ to the left?
Right is shorter (bifurcates earlier), wide and more vertical
27
What is the epithelium in the trachea?
Pseudostratified ciliated columnar with goblet cells
28
Fill in blanks: The lymphatic efferents for the rest of the body empty into the ________ ____ that is the continuation of the _______ _____ and lies between the aorta and ____ ____ in the posterior _____
The lymphatic efferents for the rest of the body empty into the THORACIC DUCT that is the continuation of the CISTERNA CHYLI and lies between the aorta and AZYGOS VEIN in the posterior MEDIASTINUM
29
What are the 3 clusters of mediastinal nodes and where do they drain to?
1. Superior tracheobronchial 2. Inferior tracheobronchial 3. Anterior mediastinal On the left, nodes drain to thoracic duct On the right, nodes drain to thoracic lymph duct [Tracheobronchial nodes are clustered at the tracheal bifurcation]
30
What two factors must be controlled to maintain tissue perfusion across the whole body?
Constant arterial blood pressure | Control distribution of total cardiac output
31
Mean arterial blood pressure=
MABP= CO x Total Peripheral Resistance
32
Where are the two baroreceptors located and what is their innervation?
``` Carotid body (chemoreceptor): Located at bifurcation of common carotid artery. Innervated by glossopharyngeal nerve Aortic baroreceptor: In walls of aorta, innervated by vagus nerve ```
33
How do baroreceptors detect changes in bp?
Operate as stretch receptors | Firing rate Increases/decreases with bp changes
34
What is the primary purpose of baroreceptor reflex?
To reduce minute-to-minute variations of arterial pulse
35
How do cardiopulmonary baroreceptors differ from baroreceptors?
1. Sense central blood volume ("low pressure receptors") in atria, ventricles, veins and pulmonary vessels 2. If rate of firing decreases: - Sympathetic nerve activity to heart and blood vessels increases - Parasympathetic nerve activity to the heart decreases
36
What is the Bainbridge Reflex?
Atrial reflex control of BP: Sympathetic-mediated reflex in response to increased blood in the atria. This increases HR and contractility If aortic/carotid baroreceptors sense high pressure, Bainbridge reflex can over-ride
37
What is the Medullary Cardiovascular Control (MCVC) vasomotor centre?
Consists of 3 regions located on the Medulla: 1. Sensory area: Input from baroreceptors 2. Lateral portion: Efferent sympathetic nerves 3. Medial portion: Effect parasympathetic (vagal) nerves
38
What is responsible for the continuous low-level tone of vessels?
Sympathetic nerves exerts vasomotor tone on vessels which keeps them partially constricted. [NOTE veins are innervated by sympathetic. Decrease capacitance --> increase in venous return, stroke volume and then cardiac output]
39
What is the CNS ischemic response?
Emergency pressure control system When blood flow to the MCVC centre is v low: 1. Increase in peripheral vasoconstriction 2. Increase sympathetic stimulation of heart 3. Increase systemic arterial pressure
40
What are two examples of acute auto-regulation if bp increases?
Myogenic theory: Stretch-induced vascular depolarization of smooth muscle due to increases arterial pressure Metabolic theory: Increase arterial pressure increases oxygen and washes out local factors
41
What is the journey of the thoracic aorta?
From: T4/5, 2nd CC To: Aortic hiatus in the diaqphragm (T12) between the crura and behind the median arcuate ligament
42
What are the 5 main types of branches of the thoracic aorta?
1. Oesophageal arteries supply the middle third of oesophagus 2. 9 posterior intercostal arteries supply the lower 9 intercostal spaces 3. Subcostal arteries lie inferior to the 12th rib, supply posterior abdominal wall 4. Bronchial arteries vary (usually 2 lift and 1 right)
43
The middle _______ is supplied by branches from the aorta, and therefore it drains to the ____ vein
The middle OESOPHAGUS is supplied by branches from the aorta, and therefore it drains to the AZYGOS vein
44
What vessels do the following arteries arise from: - Internal thoracic? - Anterior intercostals? - Posterior intercostals?
Internal thoracics arises from the subclavian arteries Anterior intercostals arise from the internal thoracic arteries Posterior intercostals arise from the aorta
45
How does the muscle vary in the oesophagus?
Upper 1/3: Striated muscle (as swallowing is voluntary and rapid) Middle: Mixed Upper 1/3: Smooth muscle, involuntary
46
What mechanism is there to prevent air being sucked into the stomach during inhalation?
Indentation caused by the normal function of the cricopharyngeal sphincter, between the pharynx and the oesophagus
47
What 3 features of the oesophagus allow the cardiac sphincter that prevents gastric reflux?
1. The lower oesophagus passes through the right crus of the diaphragm 2. It has an oblique entry into the stomach 3. Resting tone of the smooth muscle of the lower oesophagus
48
``` For the superior/cervical third of the oesophagus: Arterial supply? Venous drainage? Nerve supply? Lymph drainage? ```
Arterial supply: Inferior thyroid arteries Venous drainage: Brachiocephalic veins Nerve supply: Branches of the vagus nerve (recurrent laryngeal nerves) Lymph drainage: Deep cervical nodes
49
``` For the middle third of the oesophagus: Arterial supply? Venous drainage? Nerve supply? Lymph drainage? ```
Arterial supply: Thoracic aorta and bronchial arteries Venous drainage: Azygos system Nerve supply: Oesophageal plexus Lymph drainage: Tracheobronchieal nodes
50
``` For the inferior/abdominal third of the oesophagus: Arterial supply? Venous drainage? Nerve supply? Lymph drainage? ```
Arterial supply: Left gastric artery Venous drainage: Left gastric --> Portal vein Nerve supply: Branches of oesophageal plexus Lymph drainage: Left gastric and coeliac nodes
51
What is the effect of cirrhotic liver disease on the veins?
Cirrhotic liver disease raises the portal venous pressure (ie portal hypertension) and blood escapes via the submuscosal veins in the oesophagus and into the systemic azygos vein. Hence the veins become dilated and tortuous
52
What are the 4 oesophagus constrictions?
1. Upper oesophagus sphincter 2. Arch of aorta 3. Left main bronchus 4. Diaphragm
53
What side does the thoracic duct lie?
THE LEFT HAND SIDE ONLY
54
Where does the thoracic duct drain into?
The junction of the left internal jugular and left subclavian vein (ie the left brachiocephalic vein)
55
When undertaking thoracic surgery great care must be taken to avoid damage to the thoracic duct as leakage of lymph will cause a _______
Chylothorax
56
On the left the thoracic duct enters the left brachiocephalic vein, after receiving lymph from which 3 trunks?
1. Jugular lymph trunk 2. Subclavian lymph trunk 3. Bronchomediastinal trunk [All from LHS]
57
On the right the lymph drains into the right brachiocephalic vein, from which 3 trunks is this lymph originating?
1. Jugular lymph trunk 2. Subclavian lymph trunk 3. Bronchomediastinal trunk [All from RHS] [All may fuse before entry to form the RIGHT LYMPHATIC DUCT]
58
Where does the azygos drain?
The posterior wall of the thorax by received vein equivalents of the branches of the descending aorta
59
What 3 main vessels make up the azygos system?
1. Azygox vein 2. Hemi-azygos (lower) vein 3. Accessory (upper) azygos vein
60
What are the two primary determinants in the regulation of the blood pressure?
1. The renal output curve of salt and water 2. The level of salt and water intake At least one needs to change to have long term effect
61
How is ADH release stimulated?
1. Increase in osmotic pressure detected by hypothalamic osmoreceptors 2. Hypovolemia detected by atrial baroreceptors 3. Angiotensin II
62
Describe how the renin-angiotension-aldosterone system (RAAS) achieves in increased arterial pressure?
1. Renin is released from the kidney juxtoglomerular cells 2. Production of angiotension II - Constricts renal arteries - Release of aldosterone from adrenal glands, increase Na and Water reabsorption - Release of ADH from pituitary
63
What is purpose of atrial-natriuretic hormone release?
1. In response to stretch of the atria | 2. Helps oppose the offects of the RAAS
64
``` Describe the response of the following factors to HYPOVOLEMIA at the point of haemorrhage and reflex compensations: SV? HR? CO? TPR? MABP? ```
SV: Drops then increases partially HR: Stays same, then increases due to sympathetic innervation CO: Drops, then increases partially TPR: Same the increases due to vasoconstriction MABP: Drop then returns to normal Later response to hypovolemia: Arteriolar constriction of renal arteries, promotes fluid reabsorption.
65
What interventions can be made if volume of fluid lost cannot be compensated for?
Fluid replacement required: - Resus fluids (colloid/Hartmann's/blood) - Fluid challenge algorithm
66
How does your cortex, the time of day and respiration affect blood pressure control?
Cortex: Conscious effects of emotions via the nerves from cortex to MCVC centre Time of day: Diurnal variations due to hormones and cortical input Respiration: Mechanical movement, chemoreceptors
67
Why is medicine a difficult environment in which to admit or report errors?
1. Admitting mistakes has risk of admitting incompetence? 2. Medicine is not an exact science 3. A "norm of non-criticism" 4. Whistle-blowing is not easy
68
What are the common causes of basic errors in medicine?
1. Stress 2. Fatigue 3. Covering for colleagues 4. Professional culture (unwillingness to use support structures) 5. Feeling that decisions must be made alone 6. Unable to admit to uncertainty
69
What requirements were set by the Duty of Candour in 2015?
Created a legal requirement for health and social care organisations to inform patients when they have been harmed as a result o the care they have received.
70
What are the 4 steps involved in the professional Duty of Candour set by the GMC?
TELL the patient when something has gone wrong APOLOGISE to the patient OFFER an appropriate remedy EXPLAIN fully to the patient the short and long effects of what has happened
71
Describe the three elements that comprise an action in negligence. Negligence is the legal approach a patient may take in response to error/inadequate care.
The claimant must establish: 1. She/he is owed a duty of care by the defendant 2. That the defendant breached that duty by failing to provide reasonable care 3. That the breach of duty caused the claimant's injuries, and that those injuries are in close proximity
72
Define the Bolam test?
A doctor is not guilty of negligence if he has acted in accordance with a practice accepted as proper by a responsible body of medical men in that particular art ie If others would've done the same, then you're in the clear. Risk of bias
73
What is the Bolitho test?
Modified Bolam to add: The professional opinion must be capable of withstanding logical analysis
74
What is causation?
During a complaint, there must be a clear link between the action (or inaction) of a doctor and the harm the patient experienced. Key factor= proximity.
75
Contrast what is meant by a person-centred approach and a systems-based approach to addressing medical errors
Person-centred approach: When the focus is on the individual doctor Systems-based approach: Considered the environment, seeks to minimize opportunities for error
76
Identify ways of reducing errors through a systems-based approach
1. Dedication centres: Beneficial for less common procedures 2. Require to retrain: Keeps skills up to date with new procedures and techniques 3. Data collection of incidents: Scottish Patient Safety Research Network set up to improve safety through collecting data 4. Improved instrument design 5. Protocols and guidelines 6. Checklists 3,4,5,6: Growing understanding of importance of "human factor" approach
77
Right and Left Vagus Nerves: 1. Carry _____ fibres to the thoracic and abdominal viscera 2. They are heading for the oesophagus and stomach so they lie.... 3 Carry innervation for the striated muscles of the _____ and _____ 4. Both vagus nerves give preganglioc branch to autonomica plexuses: P_____, C_____ and O_______
1. Carry PARASYMPATHETIC fibres to the thoracic and abdominal viscera 2. - Closer to the mid-line than the phrenic nerves - Pass posterior to the lung root 3. Carry innervation for the striated muscles of the pharynx and larynx 4. Pulmonary, Cardiac and Oesophageal
78
When the right vagus reaches the oesophagus, what happens?
Forms the oesophageal plexus with the left vagus. | They then reform as anterior (mainly left) and posterior (mainly right) vagal trunks as oesophagus leaves thorax
79
What 3 arteries is the left vagus nerve related ro?
LCCA LSCA Left side of Aortic Arch
80
Recurrent laryngeal nerves: 1. Given of by which nerve? 2. Provides motor branches to which muscle 3. Provides sensory innervation to what?
1. Vagus gives recurrent laryngeal nerves 2. Moton branches to the laryngeal muscles 3. Sensory to mucosa below vocal folds
81
What are two potential causes for hoarseness of the voice?
Tumour or Enlarged lymph nodes compressing the nerves
82
What are the postsynaptic neurotransmitters for sympathetic and parasympathetic innervation?
S: Noradrenaline PS: Acetylcholine
83
Explain why efferent neurons, of the Autonomic (visceral) effect nervous system, are said to be in a two-neurone chain?
The cell body of the 1st neurone lies in the CNS The cell body of the 2nd neurons is located in a ganglion Axon from first neurone synapsis on cell body of 2nd neurone in the ganglion
84
Parasympathetic nerves are distributed only to ____, ____ and _____
Parasympathetic nerves are distributed only to head, neck and viscera ( NB- no supply to the skin or to limbs)
85
What is meant by craniosacral outflow?
When the parasympathetic preganglionic neurones "hitch-like" with the cranial or sacral spinal nerves that supply only the head, neck, thoracic and abdominal pelvic viscera.
86
In parasympathetic supply, which of the 1y and 2y neurones is longer
``` The 1y (preganglionic) neurone is long The 2y (postganglionic) neurone is short ```
87
What is meant by thoracocolumbar outflow?
Sympathetic neurcones preganglionic cell bodies lie in a sympathetic ganglion They either a) Hitch-hike along somatic nerves and/or arteries and are distributed widely all over the body b)They supply adjacent viscera through autonomic plexuses
88
What are sympathetic trunks?
Preganglionic sympathetic neurones emerge from the cord in the T1 to L2 spinal nerves Cell bodies of the postganglionic neurones arranged in 2 chains of linked ganglia that lie alongside all the vertebral bodies. One chain on each side
89
What is the difference between WRC (white rami communicantes) and GRC (grey rami communicantes)?
Preganglionic neurones pass to the sympathetic trunk in white rami communicantes (WRC) and either synapse immediately in the adjacent ganglion or they travel up or down in the trunk to be distributed above T1 and below L2 After synapsing in a ganglion, the postganglionic (2y) neurone joins a spinal nerve via a grey ramus communicantes (GRC) in which it is distributed to the body wall WRC: Spinal cord to sympathetic trunk GRC: Sympathetic trunk to spinal nerve
90
At which point do the two sympathetic trunks fuse?
The ganglion impar
91
What is the stellate ganglion a fusion of?
Inferior cervical ganglion and the T1 ganglion
92
Which sympathetic primary neurones don't synapse in the trunk?
Those passing straight through the trunk to reach abdominal viscera and adrenal glands. This occurs via the greater, lesser and least splanchnic nerves.
93
Where to the following nerves synapse: 1. Greater splanchnic 2. Lesser splanchnic 3. Least splanchnic These nerves allow the 1y sympathetic neurones to synapse outwith the sympathetic trunk.
1. Coeliac ganglia 2. Superior mesenteric ganglia 3. Inferior mesenteric ganglia All examples of prevertebral ganglions
94
What neurone levels supply to lungs and heart?
T1-T5 Fibres ascend the trunk and synapse in T1 and inferior/middle cervical ganglia. Cardiac branches (2y neurone) leaves the sympathetic trunk and pass down to cardiac plexuses
95
In the ANS the neurones orginiates from which levels provide the following structures: 1 Stomach 2. Midgut derived structures and gonads 3. Hindgut
1. T7-T9 2. T10-T11 3. T12
96
What are the symptoms of horner's syndrome?
- Ptosis (dropping) of the upper eyelid - Pupillary constriction (miosis) - Anhydrosis (lack of sweating) - Flushing of the face
97
What is the effect of decreased alveolar oxygen on the local blood flow in pulmonary circulation?
Reduces blood flow as the arterioles to that region are constricted. Opposite effect to systemic circulation
98
When is the window for coronary flow?
When the arterial pressure > ventricular pressure as the coronary vessels are dilated
99
What are the 4 issues with coronary blood flow?
1. Myocardium cannot function anaerobically due to lactic acid build up 2. Arterioles close mechaniscally during systole 3. Decrease in diastolic filling during exercise 4. Increase oxygen demand and increase metabolic demand during exercise
100
What are the two main controls of coronary blood flow?
1. Primary controller is local metabolism. In proportion to need of cardiac musculature for O2. Stimulates release of vasodilators (e.g. adenosine) 2. Sympathetic stimulation
101
In sympathetic stimulation of skeletal muscle arteries, the adrenaline released from adrenal medulla causes....
Vasodilation of skeletal muscle arterioles
102
What factors promote venous return to heart?
1. Increase in skeletal muscle pump activity 2. Increase frequency and depth of inspiration 3. Increase in venous tone via sympathetic innervation
103
What is the purpose of feedforward control?
Primes the CVS so that activity is modified to suit the demand of the exercise. E.g. 1. Increasing sympathetic and decreases PS = increase CO and TPR 2. Release of ADH + vasopressin = water retention 3. Resetting of baroreceptors upwards
104
How does attempt to maintain a steady TPR during dynamic exercise?
Use of muscles increases their metabolic activity (accumulation of local factors) which stimulates vasodilation. This decreases TPR. The body then stimulates vasoconstriction to non-essential organs. If the vasodilation still outweighs the vasoconstriction, cardiac output has to increase to maintain arterial blood pressure.
105
How doesdynamicexercise alter the blood flow to the skin?
Initially the blood flow is reduced as the skin is viewed as "non-essential" As exercise continues the heat generated needs to be dissipated. Blood flow to the skin returns as it is essential for temperature regulation via radiation and sweating. As a consequences, TPR decreases
106
What is the frank-starling mechanism?
The stroke volume of the heart increases in response to an increase in the volume of blood filling the heart (the end diastolic volume) when all other factors remain constant.
107
Why does the cardiac output increase during dynamic exercise?
1. Increase sympathetic an decrease PS increases HR and stroke volume 2. Venous return to heart increases (due to vein compression between muscles), causing minor increase in EDV
108
What is end-diastolic volume (EDV)?
End-diastolic volume (EDV) is the volume of blood in the right and/or left ventricle at end load or filling in (diastole) or the amount of blood in the ventricles just before systole.
109
What is the effect of dynamic exercise on MABP?
Slight increase. | Not elevated greater greatly due to changes in CO and TPR balancing out
110
What is the effect of dynamic exercise on pulse pressure?
May increase due to increased systolic pressure (a result of increase CO in aorta) and a mild decrease in diastolic pressure (a result of decreases afterload as the TPR decreases)
111
What is the effect of static exercise of the CVS?
1. Compression of arteries and veins 2. Increase venous return 3. Increase in TPR 4. Local factor attempt to cause vasodilation but compression prevents this 5. Accumualtion of local factors cause increase in CO 6. MABP increases: as both systolic and diastolic pressures increase
112
Classify vascular diseases
Arteries: Atherosclerosis Veins: Thrombosis (phlebothrombosis vs thrombophlebitis) All vessels: Vasculitis, radiation damage Tumours
113
Describe the characteristics of atheroma and its complications
Morphology of atheromatous plaque: Core of lipid with fibrous cap Complications: Cerebral infarction, carotid atheroma, myocardial infarction, aortic aneurysym, peripheral vascular disease, gangrene
114
Define aneurysm and name the types
``` Definition: An aneurysm is a localized, permanent, abnormal dilatation of a blood vessel or the heart Types: - Atherosclerotic -Dissecting -Berry -Micro-aneurysms -Syphilitic -Mycotic ```
115
Define vasculitis
``` Inflammation and necrosis of blood vessels Pathogenesis: •Cell immune-mediated inflammation •Deposition of immune complexes •Direct attack by circulating antibodies ```
116
Classify vasculitis
1. Giant-cell (temporal) arteritis: over 50s 2. Takayasu arteritis (pulseless disease): Of the upper limb 3. Polyarteritis nodosa (PAM): of visceral organs 4. Kawasaki disease (children less than 4yrs)
117
What is peripheral vascular disease and its 4 effects?
``` PVD is atheroma of distal aorta/iliac/femoral arteries which causes ischaemia of lower limbs Effects: 1. Intermittent claudication 2. Pain 3. Ulcers 4. Gangene ```
118
Where are atherosclerotic aneurysms normally found and what is their morphology?
Location: Abdominal aorta, distal to renal arteries Morphology: -Saccular/fusiform -15-25cm -Wall diameter is greater than 50% -Frequently contains mural thrombus (adhered to bv wall)
119
``` Atherosclerotic aneurysm: Location? Morphology? Clinical consequences? Presentation? ```
Location: Abdominal aorta, distal to renal arteries Morphology: -Saccular/fusiform -15-25cm -Wall diameter is greater than 50% -Frequently contains mural thrombus (adhered to bv wall) Clinical consequences: -Thrombosis -Embolism -Rupture -Obstruction of a branch vessel Presentation: An abdominal pulsating mass
120
``` Atherosclerotic aneurysm: Location? Morphology? Clinical consequences? Presentation? ```
Location: Abdominal aorta, distal to renal arteries Morphology: -Saccular/fusiform -15-25cm -Wall diameter is greater than 50% -Frequently contains mural thrombus (adhered to bv wall) Clinical consequences: -Thrombosis -Embolism -Rupture -Obstruction of a branch vessel Presentation: An abdominal pulsating mass
121
Dissecting aortic aneurysm: Found in? Morphology? Clinical symptoms?
Found in: -Men with hypertension -Younger patients with systemic or localized abnormalities of connective tissue Morphology: -Usually initiates with an intimal tear. -1-2cm from aortic valve -Dissection can extend along the aorta retrograde toward the heart... or.... -Distally sometimes into the iliac and femoral arteries Clinical symptoms: -Sudden onset of excruciating pain (beginning in the ant. chest, radiating to the back) -The most common cause of death is rupture of the dissection outward into he pericardial, pleural or peritoneal cavities
122
Berry aneurysms: Where? Found in? Associated with?
Location: Circle of Willis Found in: Young hypertensive people Association: Sub-arachnoid haemorrhage
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Capillary micro-aneurysms: Associated with? Define? Associations?
Associations: Hypertension, diabetes Definition: Small aneurysms of branches of middle cerebral artery Association: Intra-cerebral haemorrhage
124
What vessel do syphilitic aneurysms using affect?
The thoracic aorta
125
Mycotic aneurysm: Define? Location?
Definition: Wall of the artery weakened by infection Location: In brain, secondary to embolism
126
``` Varicose veins: Define? Risk factors? Cause? Conseqences? ```
``` Varicose veins: Abnormally dilated, tortuous veins produced by prolonged, increased intraluminal pressure and loss of vessel wall support Risk factors -Age -Sex -Heredity -Posture -Obesity Cause: Incompetent venous valves Causes: Stasis, congestion, oedema, pain and thrombosis, skin ulceration and bleeding ```
127
Classify vascular tumours
Benign: - Angioma - Haemangioma: Juvenile (strawberry), capillary (ruby spots), cavernous (port wine stains), capillary + cavernous Malignant: -Angiosarcoma: Skin, soft tissue, breast, bone, liver, spleen
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What is oncotic pressure?
Oncotic pressure, or colloid osmotic pressure, is a form of osmotic pressure exerted by proteins, notably albumin, in a blood vessel's plasma (blood/liquid) that usually tends to pull water into the circulatory system.