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3rd Year BDS > Human Disease > Flashcards

Human Disease Flashcards

1
Q

What is the function of an osteoblast?

A

It forms bone

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2
Q

What is the function of an osteoclast?

A

It resorbs bone

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3
Q

What differentiate to form osteoblasts?

A

Mesenchymal progenitor cells

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4
Q

What differentiates to form osteoclsts?

A

Myeloid progenitor cells

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5
Q

Name 5 cell signalling ligands stimulate the activity of osteoblasts?

A 
TNFa
IL-1
IL-11
PTH
PGE2
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6
Q

What do osteoblasts release to activate the differentiation of osteoclasts?

A

RANKL

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7
Q

What vitamin is essential for bone health?

A

Vitamin D

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8
Q

Explain the 4 steps in the cycle of vitamin D formation in our body?

A
  1. Photons from sun hit skin
  2. 7DHC is activated and travels to the liver
  3. At the liver it is converted to 25(OH)vit D (then stored)
  4. It then travels to the kidney and becomes 1,25(OH)2 vit D (physiologically active)
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9
Q

What ion is essential for bone formation/turnover?

A

Calcium

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10
Q

If Ca is low what occurs?

A

Bone resportion

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11
Q

If Ca is high what occurs?

A

Bone formation

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12
Q

What are the 5 main substances that aid the control of Ca metabolism? and which organs?

A 
Ascorbic acid
Vit D
Ca
PTH
PO4

Bone
GI
Parathyroid gland
Kidney
Liver
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13
Q

What is the definition of Paget’s disease of the bone?

A

Localised disorder of bone turnover
Increased bone resorption followed by increased bone formation
Leading to disorganised bone: bigger, less compact, more vascular and more susceptible to deformity and fracture

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14
Q

How is Paget’s disease of the bone transmitted?

A

Genetically (15-30% familial)
Anglo-Saxon origins
Chronic viral infection within osteoclasts

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15
Q

What are the symptoms for Paget’s disease?

A

> 40 age with bone pain
Bone deformity
Excessive heat over pagetic bone
Neurological complications such as nerve deafness

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16
Q

What are the presentations of Paget’s disease?

A

Isolated elevation of serum alkaline phosphatase
Bone pain and local heat
Bone fracture or deformity
Hearing loss

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17
Q

What is the treatment for Paget’s disease?

A 
Surgical intervention (hard if asymptomatic)
Don't treat if raised alkaline phosphatase alone
IV bisphosphonates therapy with one off IV zoledronic acid
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18
Q

What is the difference between Rickets and Osteomalacia?

A

Rickets - before the epiphyseal lines are closed

Osteomalacia - adult disease

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19
Q

What is the definition of Rickets and Osteomalacia?

A

A severe vitamin D or Ca deficiency causing insufficient mineralisation
Muscle function is also impaired in low vit D states

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20
Q

How are vitamin D and Ca related?

A

Vit D stimulates the absorption of Ca and PO4 from the gut and Ca and PO4 then becomes available for bone mineralisation

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21
Q

What is the presentation of Rickets?

A 
Stunted growth
Curved spine
Wide joints at elbow and wrist
Curved legs (splayed)
Wide bones and ankles
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22
Q

What are the symptoms for Osteomalacia?

A

Aches and pains
Inability for muscle coordination
Waddle gait
Struggle out of chair

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23
Q

Treatment for Osteomalacia and Rickets?

A

Ca and vit D supplementation

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24
Q

What is the definition of osteogenesis imperfecta?

A

Genetic disorder of CT characterised by fragile bones from mild trauma or everyday acts

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25
What are the 4 most common phenotypes for osteogenesis imperfecta?
28 different genetic variation exist Type I: milder form when child starts to walk but can present in adults Type II: lethal by age 1 Type III: progressive deforming with severe bone dysplasia and poor growth Type IV: more severe version of type I
26
What is the presentation for osteogenesis imperfecta?
``` Growth deficiency Defective tooth formation hearing loss Blue sclera Scoliosis Ligamentous laxity Easy bruising ```
27
What is the surgical, medical, social and genetic management options for osteogenesis imperfecta?
Surgical to treat fracture Medical to prevent fracture via IV bisphosphonates Social adaptations to education and social Genetic via counselling for parents and next generation
28
What is the definition of osteoporosis?
A metabolic bone disease characterised by low bone mass and micro architectural deterioration of bone tissue, leading to enhanced bone fragility and a consequent increase in fracture risk T- score < -2.5 SDs
29
What other factors increase the risk of bone fractures?
Age BMD Falls Bone turnover
30
What is a good website to calculate the risk of fracture for a patient?
Frax
31
What T-score is needed for an osteoporosis diagnosis?
< -2.5 SDs
32
What type of scan is used to help diagnose osteoporosis?
Dual energy x-ray absorptiometry (DXA)
33
How common is osteoporosis, for men and women?
50% of women over 50 will have an osteoporotic fracture before death (Men 1/5) A 50 year old women had a 17% risk of hip fracture
34
What are the endocrine causes of osteoporosis?
``` Thyrotoxicosis Hyper/Hypoparathyroidism Cushings Hyperprolactinemia Hypopituitarism Early menopause ```
35
Which rheumatic disease can cause osteoporosis?
RA Ankylosing spondylitis Polymyalgia rheumatica
36
Which GI disease can cause osteoporosis?
UC and Crohn's Liver disease Malabsorption
37
Which medications can cause an increase risk of osteoporosis?
``` Steroids PPI (proton-pump inhibitors) Enzyme inducing antiepileptic medications Aromatase inhibitor GnRH inhibitors Warfarin ```
38
What preventions can be put in place to reduce osteoporotic fractures?
Minimise risk factors Ensure good Ca and vit D status Fall prevention strategies Medications
39
What is the treatment for osteoporosis?
HRT until 60 years old Selective oestrogen receptor modulators Bisphosphonates Denosumab
40
What are the side effects of HRT?
Increased risk of blood clots Increased risk of breast cancer Increased risk of heart disease and stroke
41
What are the side effects of SERMS?
Hot flushes Increased clotting risks Lack protection at hip site
42
What are the side effects of bisphosphonates?
Oesophagitis Iritis/Uveitis Atypical femoral shaft fractures Necrosis of the jaw
43
What is Denosumab?
Monoclonal antibody against RANKL Reduces osteoclastic bone resorption Subcut injection every 6 months
44
What are the side effects for Denosumab?
Allergy Symptomatic hypocalcemia if given when vit D is deplete Atypical femoral shaft fractures
45
What are the side effects of Teriparatide?
Injection site irritation Rarely hypercalcaemia Allergy
46
What common features do all CT diseases share?
Auto-antibodies present Mainly female All have oral features
47
What antibody can be used to support a clinical diagnosis?
ANA (95% +ve in CTD) | Lupus
48
What are the oral presentations for systemic lupus?
1/1000 ``` Oral ulcers (painless) Dry mouth/eyes ``` (Fatigue, arthralgia and malar rash across nose)
49
What are the treatments for systemic lupus, specifically oral symptoms?
Aspirin Immunosuppressive medications )sides thrush and ulcers) (methotrexate and rituximab) Check patients bloods Suncream, hydroxychloroquine, anti-inflamm and steroids
50
What are the oral presentations for Sjogren's syndrome?
Dry mouth (xerostomia) --> dental decay and oral infection Salivary gland swellings Dry eyes (xerophthalmia) --> burning and gritty eyes Fatigue Arthralgia
51
How to confirm a suspicions of Sjogren's?
Schirmer's test, saliva test, blood test (RO and La antibodies) Labial gland biopsy (referral)
52
What are the 2 types of Sjogren's?
Primary (just the disease) | Secondary (complication of other CTDs)
53
What is the treatment for Sjogren's, specifically for oral symptoms?
Saliva substitutes: water, BioXtra oral gel, Saliva Othana, Biotene oral gel, High Fl toothpaste Sugar free chewing gum Regular dental check ups
54
What are the 2 types of scleroderma?
Localised: morphoea Systemic: limited and diffuse
55
What are the presentations for systemic sclerosis?
Limited mouth opening Poor dentition Gum recession Secondary Sjogren's ``` Adult onset Raynaud's Swollen hands/sausage fingers Tight waxy skin Fatigue Dysphagia ```
56
What is the treatment for systemic sclerosis?
Immunosuppression (methotrexate) Anti-fibrotic Vascular (ca channel blockers - nifedipine)
57
What are the presentations for inflammatory muscle disease?
Dry mouth and eyes due to secondary Sjogren's Dysphagia Muscle weakness Rash Rapid loss of function (need aid out of chair)
58
What are the 2 types of inflammaotry muscle disease?
Dermatomyositis | Polymyositis
59
What is the treatment for inflammatory muscle disease?
Steroid Immunosuppressives IV Immunoglobulins
60
What is the definition of antiphospholipid syndrome?
Sticky blood disorder | have it or its abs
61
What is the clinical presentation of antiphospholipid syndrome?
Recurrent thrombosis Recurrent pregnancy loss Peculiar rash (levido reticularis)
62
What is the lab presentation of antiphospholipid syndrome?
Anticardiolipin antibody Lupus anticoagulant Anti-beta 2 glycoprotein
63
How to treat someone with antiphospholipid syndrome and what effect does this have on dental procedures?
Antiplatelets Anticoagulants High bleeding risk
64
What are the presentations for Behcet's disease?
Recurrent painful oral ulcers
65
What are the presentations for giant cell arteritis?
Jaw pain Jaw Cramps/claudications Tongue pain
66
What are the presentations for juvenile idiopathic arthrtis?
Micrognathia | TMJ involvement
67
What medications give side effects such as oral ulcers?
Methotrexate Sulfasalazine Fetunomide Mycophenolate mofetil
68
What medications give side effects such as dry mouth
Amitriptyline
69
What medications give side effects such as thrush?
Steroids | Immunosuppressants
70
What medications give side effects such as metallic taste?
Penicillamine | Sulfasalazine
71
What medications give side effects such as gum hypertrophy or staining?
Cyclosporin
72
What are the 2 main causes of autoimmunity?
Genetic: susceptible genes that lead to a failure of self-tolerance Environmental stimuli: tissue damage leading to presentation of self-antigens activating self-reactive lymphocytes
73
What is the definition of autoimmune disease?
A failure or breakdown of immune system that maintains tolerance to self tissues
74
How does the immune system change for someone who is autoimmune?
Loss of tolerance is due to abnormal selection or lack of control of self-reactive B/T cells
75
What is the definition of a hypersensitivity response?
A harmful immune response that may produce tissue injury or cause serious disease
76
What is each type of hypersensitivity reaction mediated by?
TI-III - antibodies | TIV - T cells
77
What type of hypersensitivity does autoimmune disease fall under?
TII-IV
78
What is he antibody, ligand, MoA and general name for type I hypersensitivity?
IgE Soluble antigen Act mast cells and produce mediators Allergy
79
What is he antibody, ligand, MoA and general name for type II hypersensitivity?
IgG, IgM Cell or matrix antigen Opsonisation, phagocytosis, complement and act of leukocytes Rheumatic fever
80
What is he antibody, ligand and general name for type III hypersensitivity?
IgG, IgM Soluble antigen Complement, Fc receptor recruitment and act of leukocytes RA
81
What is he T cell variation, ligand, MoA and general name for type IV hypersensitivity?
Th1 - sol antigen TI diabetes (delayed-type) Th2 - sol antigen MS (T cell mediated) (both produce inflammatory cytokines) CTL - cell antigen Th1 - macrophage activation causing cytokine-mediated inflamm Th2 - direct cell killing and cytokine mediated inflammation
82
Explain the process of type I hypersensitivity?
1. Exposure to allergen 2. Act of Tfh cells and stimulation of IgE class switching in B cells 3. Production of IgE 4. Binding of IgE to FceRI on mast cells 5. Repeated exposure to allergen 6. Activation of mast cell; releasing medicators 7. Mediators such as cytokines and vasoactive amines and lipid
83
What are the effects of biogenic amines (histamine)
Vasodilation | Vasc leakage
84
What are the effects of lipid mediators (PAF and LTC4)
Bronchoconstriction intestinal hypermotility | Inflammation
85
What are the effects of cytokines (TNF)
Inflammation
86
What are the effects of cationic granule proteins?
Killing parasitic cells
87
What are the effects of enzymes?
Tissue damage
88
Explain the mechanism of action of type II hypersensitivity?
Antibody binding to antigen Recruit and activate inflammatory cells (via complement and Fc receptor) (neutrophils and macrophages) Causing tissue injury
89
Explain the mechanism of action of type III hypersensitivity?
Soluble immune complexes of antibodies and antigens Recruit and activate inflammatory cells (via complement and Fc receptor) (neutrophils) Causing tissue injury
90
What is the MoA of 'type V' hypersensitivity
Antibody against TSH receptor Stimulates the receptor without the ligand Increase production of thyroid hormone Hyperthyroidism
91
Name 4 TII hypersensitivity disease?
Autoimmune haemolytic anaemia Insulin-resistant diabetes Myasthenia gravis Graves' disease
92
Name 3 TIII hypersensitivity disease?
Systemic lupus Polyarthritis Poststreptococcal glomerulonephritis
93
Name 3 TIV T cell mediated hypersensitivity diseases and their antigen targets?
TI diabetes - Islet cells RA - TII collagen MS - myelin basic protein
94
Theoretically, how can we treat TIV hypersensitivity?
Blockade of CD4 or MHC II molecules with blocking antibodies | Or blockage of CTLA-4 (T-cell inhibitor)
95
What part of genetics can influence autoimmunity?
HLA alleles
96
What HLA does RA have?
DR4
97
What HLA does Insulin-dependent diabetes have?
DR3/DR4
98
What HLA does MS have?
DR2
99
What HLA does systemic lupus have?
DR2/DR3
100
What gene polymorphisms in HLA can cause increased susceptibility to autoimmune disease?
IL-10
101
What are the potential mechanisms of environmental causes for autoimmunity?
Molecular mimicry Viral/bacterial superantigens Enhanced presentation and processing of autoantigens Bystander activation Act of lymphocytes by lymphotropic viruses
102
What is the definition of molecular mimicry?
Activation of autoreactive T cells by microbial peptides that have sufficient structural similarity to self peptide
103
What is the definition of viral/bacterial superantigen?
Activation of autoreactive T cells that express particular Vbeta segments
104
What is the definition of enhanced presentation and processing of autoantigens?
Enhanced presentation of autoantigens by APC recruited to inflammatory site, followed by priming of autoreactive lymphocytes
105
What is the definition of bystander activation?
Expansion of previously activated T cells at inflammatory site
106
What is the definition of activation of lymphocytes by lymphotropic viruses?
Viral infection of lymphocytes, such as infection of B cells with Hepatitis C virus, resulting in enhanced antibody production and formation of circulating immune complexes
107
What is a good example for molecular mimicry and MoA?
Rheumatic fever: | - streptococcal A antibodies bind M protein, then cross react with cardiac myosin
108
What are the types of autoimmune disease?
Systemic and organ specific
109
What is the definition of systemic autoimmune disease?
Spread throughout the body
110
What is the definition of organ specific autoimmune disease?
Directed towards one organ
111
What are the oral presentations of systemic lupus?
``` Mouth ulcers Facial rash (butterfly) ```
112
What is TI diabetes' mainly mediated by and what does it attack?
By CD4 and attacks islet cells and insulin and GAD65
113
What are the oral presentations of oral lichen planus?
Papular skin eruptions | Chronic desquamative gingivitis
114
What is the treatment for oral lichen planus?
Mouthwash
115
What is oral lichen planus' mainly mediated by and what does it attack?
CD8 cells | Targeting keratinocytes
116
What is the oral presentation of TI diabetes?
Increased caries risk
117
What is the definition of arthritis?
Inflammation of joints
118
What are the symptoms of arthritis?
Pain Stiffness Swelling Functional impairment
119
What are the clinical signs of arthritis?
Tenderness Restriction of movement Heat Redness
120
What is the definition of RA?
A chronic autoimmune systemic illness characterised by a symmetrical peripheral arthritis and other systemic features, associated with joint damage
121
Explain the classification for RA?
``` Categories such as: - joint involvement - serology - acute phase reactants - duration of symptoms A score >6/10 is classified as having definite RA ```
122
What are the aetiologies for RA?
``` Genetic: - associated with position 70-74 of DRBeta1 Environmental: - smoking - chronic infection (perio disease) ```
123
What is the pathology of RA?
Synovitis: - bone erosion - swollen and inflamed synovial membrane - inflamed synovium - inflamed joint capsule - destruction of cartilage - long term joint damage
124
What test to request to identify if a patient has RA?
Anti-cyclic citrullinated antibodies test (ACPA) | MRI to identify inflammation
125
If patient has arthritis, what should you ask about?
Where specifically the arthritis is? | If neck, be careful during extra-oral and intra-oral examinations, as neck is very tender
126
What are the non-specific features of systemic RA?
Fatigue Weight loss Anaemia
127
What are the specific features of systemic RA?
Mouth, eyes, lungs, nerves, skin and kidneys
128
What are the long term features of systemic RA?
CV disease | Malignancy
129
What is a good website to assess a patient's disease score? What are the score ranges?
das28.com DAS < 2.4 represents clinical remission DAS > 5.1 eligibility for biologic therapy
130
What are the 4 therapeutic categories for the treatment of RA?
NSAIDs Disease modifying anti-rheumatic drugs Biologics Corticosteroids
131
What is the definition of Disease modifying anti-rheumatic drugs (DMARD)?
A group of structurally unrelated, typical small molecule drugs which have demonstrated to have a slow onset effect on disease activity and retard disease progression, but have been associated with toxicity profiles and risk of occasional serious adverse events
132
Name 4 examples of DMARDs for RA?
Methotrexate Sulfasalazine Hydroxychloroquine Leflunomide
133
What is the approach for management and treatment of RA?
Early and aggressive intervention is key to obtaining optimal outcomes Effective suppression of inflammation
134
Why is methotrexate the golden standard?
``` Effective Well-tolerated Cheap People stay on it Can be combined with DMARD or biologics ```
135
What is the definition of biologic DMARDs?
Large complex proteins which need to be given via injection, they work rapidly and are well tolerated but with important toxicities
136
Name 6 biologic DMARDs for RA?
TNFa inhibitors (first line) IL-1/6 inhibitors Anti B/T cell therapies Oral kinase inhibitors
137
What are the side effects of biologic DMARDs?
Injection site reaction Infection Possible malignancy
138
When can you use corticosteroids for RA?
Short term | In combination with other treatments for RA
139
What are the outcomes for RA sufferers?
50% will be unable to work due to disability within 10 years of diagnosis Increased number of sick days 75% of cases diagnosed during working life
140
Where to position the blood pressure cuff on the arm?
It should be over the brachial artery, above the elbow | Place the stethoscope on the artery to listen for sounds
141
What are the key Korotkoff sounds?
I: artery just opening after reliving of some pressure - SYSTOLIC V: silent artery, artery fully open - DIASTOLIC
142
Process of measuring blood pressure?
1. Place tourniquet over the brachial artery, above the elbow - line on tourniquet should line up with the brachial artery 2. Place stethoscope over artery Inflate tourniquet until the artery is fully occluded 3. Behind to deflate the tourniquet slowly and once the first sound is heard record the pressure value - this is the systolic pressure 4. Continue to release the pressure from the tourniquet, until the artery is fully open and the sound has become silent - this is the diastolic pressure
143
How should the patient be positioned?
Arm on table | Level with heart
144
What is the definition of osteoporosis?
Low bone mass and microarchitectural deterioration of bone tissue
145
What are the risk factors for osteoporosis?
Rheumatic disease Malabsorption Endocrine Medication
146
What is the absorption and T1/2 of bisphosphonates?
Very poor intestinal absorption 50% goes to skeleton, rest excreted via kidney Long skeletal retention, with T1/2 of 10 years
147
What are bisphosphonates?
Pyrophosphate analogues | 2 phosphates linked to C
148
What is the function of bisphosphonates?
Prevent loss of bone density and decrease risk of fractures
149
How do bisphosphonates work?
Stimulate osteoclast apoptosis and inhibit cholesterol synthesis pathway This decreases osteoclast numbers and decrease bone resorption
150
Chemically, how are 2nd and 3rd generation bisphosphonates different?
2nd: N side chain 3rd: N heterocyclic ring
151
Name 3 2nd generation bisphosphonates?
Alendronate Ibrandronate Pamidronate
152
Name 2 3rd generation bisphosphonates?
Risedronate | Zoledronate
153
What is the definition of Medication Related Osteonecrosis of the Jaw (MRONJ)?
It is defined as exposed bone, or bone that can be probed through an intraoral or extraoral fistula, in the maxillofacial region that has persisted for more than eight weeks in patients with a history of treatment with anti-resorptive or anti-angiogenic drugs, and where there has been no history of radiation therapy to the jaw or no obvious metastatic disease to the jaws.
154
What are the systemic risk factors for MRONJ?
``` Genetics Disease Age Obesity Alcohol Steroid therapy Tobacco Sex ```
155
What are the medication related risk factor?
Total dose | Length of treatment
156
What are the local factors related to risk factors?
Microtrauma Inflamm disease Oral surgery Oral implantology
157
What is the pathogenesis of MRONJ?
``` Inflamm/infection Microtrauma Altered bone remodelling or over suppression of bone resorption ANgiogenesis inhibition Soft tissue BPs toxicity Peculiar biofilm of the oral cavity terminal vascularisation of the mandible Suppression of immunity Vit D deficiency ```
158
Risk assessment for MRONJ?
No risk - if no meds Low risk - if on meds but not previous diagnosis Higher risk - if on meds for <5 years
159
Dental advice for a patient with MRONJ?
``` Healthy diet and reducing sugary snacks and drinks Excellent oral hygiene Fl toothpaste and mouthwash Stop smoking Limit alcohol Regular dental check ups ```
160
What symptoms should an MRONJ patient report to the dentist?
``` Exposed bone Loose teeth Non-healing sores or lesions Pus Tingling Numbness or altered sensations Pain Swelling ```
161
What are the treatments for established MRONJ?
Surgical Gentle debridement (best) Avoid resection Remove sequestra
162
What is a medical management for MRONJ?
Teriparatide
163
Why is stroke relevant to dentists?
Seeing older patients A link between oral health and risk of stroke OH poor after stroke
164
Risk factors at the dentists for stroke?
Invasive treatments
165
When do most strokes occur across the population?
75% over the age of 65
166
What fraction of patients die within 1 year after their stroke?
1/2
167
What percentage of stroke survivors become dependent on others?
50%
168
How many strokes does the UK have per year?
150,000
169
How much does stroke cost the the NHS?
8bn
170
What is the definition of stroke?
It is the sudden onset of focal neurological symptoms caused by ischemia or hemorrhage and lasting more than 24hrs Most strokes are ischaemic
171
What is the difference between a stroke and a TIA?
Symptoms usually resolve within 24hrs (usually an hour)
172
What is the definition of a hemorrhagic stroke?
Blood leaks into brain tissue
173
What's the definition of an ischaemic stroke?
Clot stops blood supply to an area of the brain
174
What are the vessels of the anterior supply to the brain?
Common carotid
175
What are the vessels of the posterior supply to the brain?
Vertebral arteries
176
What do the vertebral arteries form?
Basilar artery
177
What does the basilar artery form?
Posterior cerebral artery
178
What does the internal carotid artery form?
Middle cerebral artery
179
What does the middle cerebral artery form?
Anterior cerebral artery
180
How is the posterior and anterior blood supplies of the brain connected?
Posterior communicating artery
181
What does the carotid system of the brain supply?
Most of the hemispheres and cortical deep white matter
182
What does the vertebrobasilar system of the brain supply?
Brain stem, cerebellum and occipital lobes
183
What is the function of the frontal lobe?
Judgement, foresight and voluntary movement | Smell
184
What is the function of the motor coretx?
Movement
185
What is the function of the sensory coretx?
Pain, heat and other sensations
186
What is the function of the parietal lobe?
Comprehension of language
187
What is the function of the temporal lobe?
Hearing | Intellectual and emotional functions
188
What is the function of the Occipital lobe?
Primary visual area
189
What is the function of the Wernicke's area?
Speech comprehension
190
What is the function of the cerebellum?
Coordination
191
What is the function of the Brain stem?
Swallowing, breathing, heartbeat, wakefulness centre and other involuntary functions
192
What is the function of the Broca's lobe?
Speech
193
What would occur of there is a small stroke in the deep white matter?
Major deficit as the fibres are packed closely together
194
What are the signs and symptoms of stroke?
``` Motor: clumsy or weak limbs Sensory: loss of feeling Speech: dysarthria/dysphagia Neglect/visuospatial problems Vision: loss in one eye or hemianopia Haze palsy Ataxia/vertigo ```
195
What does the posterior circulation supply?
Pons Midbrain Hindbrain Cerebellum
196
What are the stroke symptoms that may arise from the posterior circulation?
``` Ataxia Vertigo Nystagmus Loss of consciousness (thrombus in basilar artery) Cardiorespiratory control ```
197
What are some conditions that present similar symptoms to stroke?
``` Migraine Epilepsy Structural brain lesions Metabolic disorders vestibular disorder Psychological disorders Demyelination Mononeuropathy ```
198
Name 4 causes for a stroke?
Carotid stenosis Carotid disease Atrial fibrillation Lacunar stroke (small vessel)
199
Name 2 rare causes for a stroke?
Foramen ovale hole (PFO) | Carotid dissection
200
Name 4 non-modifiable risk factors for stroke?
Previous stroke Age Male Family history
201
What is the most important modifiable risk factor for stroke?
Hypertension
202
Name 5 other modifiable risk factors for stroke?
``` Diabetes (3x) Smoking (2x) Lipids Alcohol Obesity ```
203
Over 1 minute of large vessel ischaemic stroke what can a patient lose?
1.9 million neurons 13.8 billion synapses 12km of axonal fibres
204
What is the acronym of FAST?
Facial weakness Arm weakness Speech problems Time to call 999
205
What the the immediate management for stroke?
Thrombolysis for patients if they present within 4.5 hours | Thrombectomy
206
What is the early management protocol for stroke?
Concentrates on: - swallowing - fluids and oxygen - early therapy involvement - good nursing care - aspirin (may wait 24hrs)
207
What is the best thing for someone to do for a person experiencing a stroke?
Get them to a hospital as fast as possible | Increases the chance of survival and reduce damage
208
What is the definition of clot retrieval?
Enter the artery in the arm | Tip penetrates clot and suctions it out
209
Name the investigations carried out to confirm the diagnosis for a stroke?
``` CT or MRI scan: - exclude haemorrhage - exclude tumour - define lesion Carotid doppler if anterior circulation signs Echo: - to exclude cardiac cause ```
210
Why is secondary prevention essential for stroke survivers?
7% of patient having a TIA with have another within 1 month 20% of stroke survivors will have another within 5 years Many de of cardiovascular events
211
Name 5 secondary prevention techniques for stroke survivors and TIAs?
``` Anti-hypertensives Anti-platelets Lipid lowering drugs warfarin or DOACS Carotid endarterectomy ```
212
Why do stroke patients have more oral problems?
Nil by mouth | Unable to brush teeth due to physical and swallowing problems
213
Name 6 types of cardiovascular diseases?
``` Angina MI Heart failure Transient ischaemic attack Thrombotic stroke Atrial fibrillation ```
214
What is the basic process of the formation of a atherosclerotic vessel??
Damage to the vessel wall Activation of platelets and inflammatory cells for abnormal healing Incorporation of cholesterol forming a fibrous cap
215
What can cause damage to the vessel walls?
Diabetes Hypertension Smoking
216
What drug groups can be used to reduce wall stress?
Beta blockers Renin-angiotensin system Ca blockers
217
Why do we use beta blockers to reduce vessel wall stress?
Reduces mortality in IHD and HF Reduces symptoms in angina, AF and SVT Anti-hypertensive
218
Name 3 examples of beta blockers?
Atenolol (B1) Metoprolol (B1) Propranolol (B1/2) Bisoprolol (B1)
219
Where are Beta 1 receptors found?
Aim for beta blockers Heart Kidneys: reduce renin release
220
What is the function of beta 1 receptors when activated?
Slows HR and conduction (negative chronotropic) Increases diastolic time, reduces BP Reduces contractility (negative inotropic)
221
Where are beta 2 receptors found?
SM | Skeletal muscle
222
What is the function of beta 2 receptors when activated?
Reduces tremor | Lethal bronchospasms for asthmatics, vasoconstriction and PVD
223
What are dental implications or beta blocker use?
Protects heart from deleterious effect of adrenaline | Can disguise physiological signs of significant blood loss
224
Why do we use ACE inhibitors and angiotensin receptor antagonists to reduce stress in vessel walls?
Reduce mortality and progression of disease in IHD, CVD and renal disease with proteinuria Prevent aberrant remodeling following MI (reduce aneurysm formation) Reduction in HF symptoms
225
Explain the renin-angiotensin system?
Angiotensinogen produced by liver ANG converted to ANG I by renin released from kidney in response to reduction in perfusion pressure ANG I converted to ANG II by ACE secreted by the lungs ANG II acts on adrenals leading to the release of aldosterone
226
What is the function of ANG II?
Potent vasoconstrictor: - peripheral vasc - efferent arteriole of the glomerulus
227
What is the function of aldosterone?
Retention of NA at the expense of K in the DCT of the kidney
228
Name 3 examples of ACE inhibitors?
Ramipril Captopril Lisinopril
229
What are the positive effects of ACE inhibitors?
Reduce BP Reduce afterload on heart Prevents aberrant remodelling after MI Reduces proteinuria
230
What are the negative effects of ACE inhibitors?
Reduces perfusion pressure in glom | Cough
231
Name 2 examples of Angiotensin II receptor blockers?
Losartan | Candesartan
232
What are the positive effects for Angiotensin II receptor blockers?
Reduce BP Reduce afterload on heart Prevents aberrant remodelling after MI Reduces proteinuria
233
What are the negative effects for Angiotensin II receptor blockers?
Reduces perfusion pressure in glom
234
What are dental implications ACE inhibitors and ARBs?
What NSAIDs to prescribe | Avoid if taking ACE inhibitor or has IHD, CVD or heart disease
235
Name 2 examples of aldosterone anatgonists?
Spironolactone and eplerenone
236
Why do we use aldosterone antagonists to reduce stress in vessel walls?
``` Used in HF Spiro used for HT: - enhanced diuretic effect - reduces mortality in IHD and HF - NSAIDs may be a big NO ```
237
Why do we use Ca channel blockers to reduce stress in vessel walls?
Antihypertensive agent | Reduce symptoms for Angina, AF and SVT
238
Name the 2 types of Ca channel blockers?
Dihydropyridine | Non-dihydropyridine
239
What is the mechanism of action of dihydropyridine Ca channel blockers and name 2 examples?
Block Ca entry into SM Less effect in myocardial pacemaking tissues Amlodipine Felodipine
240
What is the mechanism of action of non-dihydropyridine Ca channel blockers and name 2 examples?
Block CA entry into SM Blocks Ca entry into myocardial pacemaking tissue slow SA and AV conduction Verapamil Diltiazem
241
What are dental implications for Ca channel blockers?
Gingival hypertrophy: - specifically with dihydropyridine - poor OH and gingival inflamm as a risk factor (nifedipine and amlodipine) - Common in males and older generation - Not permanent (solve OH and stop taking drug)
242
What drug targets the ADP receptor? (as an antagonist?)
Clopidogrel Prasugrel Ticagrelor
243
What drug targets phosphodiesterase (as an inhibitor?)
Dipyridamole
244
What drug targets fibrinogen receptor (as a blocker?)
Abeximab
245
What drugs target COX I?
Aspirin | NSAIDs
246
What drug targets the thrombin receptor? (as an inhibitor)?
Vorapaxxar
247
What are dental implications anti-platelet drugs?
Interactions with NSAIDs: - potent COX inhibitors - increased bleeding risk (GI)
248
Why do we use Statins to reduce stress in vessel walls?
Primary: reduce cardiovascular risk if patient's 10 year risk >20% Secondary: after cardio event
249
What is the chemical name for a statin?
Hydroxy-methyl-glutaryl CoA reductase inhibitor (HMGCoA)
250
Name 3 examples of statins?
Simvastatin Rosuvastatin Atorvastatin
251
What are dental implications for statins?
Clarithromycin contraindicated with simvastatin and increases risk of myositis (muscle aches and pains)
252
Why do we use diuretics to reduce stress in vessel walls?
Antihypertensive effect Promote Na and water loss in kidney Reduce total content Reduce BP
253
Name 2 examples of thiazide diuretics?
Indapamide | Bendroflumethizide
254
Name 2 examples of loop diuretics and their indication?
Furosemide Bumetanide For HF
255
What are dental implications for diuretics?
Nephrotoxic effect in combo with NSAIDs
256
Why do we use anti-coagulants to reduce stress in vessel walls?
Primary or secondary prevention in CVD associated AF
257
Name 2 examples of Vit K antagonists?
Warfarin | DOACs
258
What are dental implications for anticoagulants?
``` Enhanced effect: Inhibition of cP450: - clarithromycin, azoles and antifungals Reduced effect: Induction of cP450 - rifampicin ```
259
Name 1 antianginal? and its implication for dentistry?
Nicorandil | Can cause ulceration
260
Name 2 antiarrhythmics? and its implication for dentistry?
Digoxin | Amiodarone - theoretically reduces toxic dose of lignocaine
261
What occurs during immediate response to injury?
Attempts to maintain tissue structure/function Minimise deleterious effects of injury Overlaps with the inflammatory process
262
What is the definition of regeneration?
Replaces damaged cells with new cells Leaves no trace of injury Tissue requires ongoing mitotic activity
263
What is the definition of repair?
Replaces damaged cells with fibrous CT Leaves permanent scar Occurs in non-mitotic tissues and with more severe injuries
264
What is the definition of stromal regions?
Support tissue: - CT, ECM, BVs and nerves Non-mitotic
265
What is the definition of parenchymal tissues?
Functional cells of organs Highly specialised Hepatocytes and kidney tubular cells Mitotic cells
266
What is the definition of a labile cell?
Continuous division | Often exposed to damage/abrasion and need constant replacement
267
Name 4 examples of labile cells?
Skin Oral cavity GI tract Uterus
268
What is the definition of stable cells?
Division stops when growth is complete | Still has potential for division (regen)
269
Name 3 examples of stable cells?
Hepatocytes Kidney tubular cells SM cells
270
What is the definition of fixed cells?
Incapable of mitotic division If damaged they are replaced by fibrous scar tissues Scar lacks any functional capacity
271
Name 3 examples of fixed cells?
Nerve cells Skeletal muscles cells Cardiac muscle cells
272
What is the definition of inflammatory mediators?
Released by WBCs such as monocytes and macrophages
273
Name 6 examples of inflammatory mediators?
``` TNF-a IL Interferons Arachidonic acid Leukotrienes Prostaglandins ```
274
What is the function of inflammatory mediators?
Coordinate: - blood clotting (initial vasoconstriction) - recruit immune cell infiltration (delayed vasodil - phagocytosis of debris and bacteria - new cell growth and fibroblast infiltration - angiogenesis
275
What is the definition of growth factors?
Released by fibroblasts, macrophages and endothelial cells
276
Name 5 examples of GFs?
``` PDGF FGF EGF VEGF TGF ```
277
What is the function of GFs?
Coordinate: - inflammatory response - chemotaxis - proliferation and differentiation - generation of ECM - angiogenesis
278
What GF related function do fibroblasts, macrophages, epithelial cells and neutrophils allow?
Chemotaxis Proliferation Differentiation Produce ECM
279
What is the definition of the ECM?
Locally secreted milieu that surrounds and supports the cells in 3D
280
Name the 3 different types of ECM composition?
Structural Water-hydrated gels Adhesive glycoproteins
281
What is the function of fibrous ECM? and examples of them?
Scaffolding of ECM provides framework and tensile strength Collagen Elastin
282
What is the function of water-hydrated gel ECM? and examples of them?
Provides lubrication, resilience and flexibility Proteoglycans hyaluronic acid
283
What is the function of adhesive glycoprotein ECM? and examples of them?
Provide cohesion between matrix components and cells Fibronectin Laminin
284
What are the 2 different forms of ECM?
Basement membrane | Interstitial matrix
285
What is the definition of basememnt membrane?
ECM sheet that epithelial, endothelial and SM cells lie on Physical/chemical barrier Giving structural support and strength
286
What is the definition of interstitial matrix?
``` Found between cells within tissue Abundant and consistency varies (nerves sparse but bone dense) Provides adherence (like glue) Also protects against tissue compression ```
287
How does the ECM aid in tissue repair?
Help regulate cell prolif, diff and movement Contains regulatory molecules for repair Prived a tissue framework for repair/regen However, repairing damaged tissue needs largely intact ECM
288
What occurs in tissue repair if the ECM is excessively damaged?
Impaired control Disorganisation Causing delayed or dysregulated repair
289
What are the 3 key phases for wound healing?
Inflammatory Proliferative Remodelling
290
What is the initial phase of wound healing?
Injury Stop bleeding via vasoconstriction Platelet activation and aggregation forming a fibrin clot
291
What occurs during the inflammatory phase of wound healing?
Vasodilation and increased vessel permeability This recruits plasma and WBCs to the wound site Neutrophils and macrophages ingest debris and fibrin Neutro secrete GFs to attract other immune cells Macrophages secrete GFs and stimulate angiogenesis 0-2 days
292
What occurs during the proliferative phase of wound healing?
``` Macrophage GFs stimulate: - continued angiogenesis - influx and activation of fibroblasts Fibroblasts: - variety of ECM components - secrete GFs to activate angiogenesis or further fibroblasts recruitment - this forms the granulation tissue 2-21 days duration ```
293
What is the defintion of granulation tissue?
Precursor to scar tissue Moist, red CT and develops into a mature scar Provides a framework for scar formation
294
What is the process of angiogenesis during granulation tissue formation?
Growth of new capillary buds from existing vessels Visible at wound surface eventually from new vasculature Provide blood supply
295
What is the process of fibrogenesis during granulation tissue formation?
Influx/activation of fibroblasts secrete: - hyaluronic acid and fibronectin (loose ECM) - then proteoglycans (local oedema and moistness) - finally collagen (progression to mature scar)
296
What occurs during the late proliferative phase?
Inflammation no longer apparent Fibroblasts persit producing collagen and strength the ECM Granulation tissue migrates upwards leaving scar behind (scar avascular) Upper epithelial layer proliferates, using granulation tissue as matrix Seals wound with new epithelial Some cell division replaces keratinocytes and epiderma strata
297
What occurs during the remodelling phase?
Fibroblasts continue to secrete collagen ALso secrete collagenase: - breakdown collagen fibres - prevents wound separation - remodels, shrinks and re-oriented scar Scar contracts inwards (contractile fibroblasts)
298
What are the characteristics of mature scar tissue?
``` Forms from granulation tissue Formed during late proliferative phase Pale (few BVs) Quiescent, spindle fibroblasts Dense collagen Elastic fibres Wound site filled in ```
299
How does regeneration differ to repair?
``` May show different profile of GFs Fewer fibroblasts and less ECM fill in Greater emphasis on division of regenerating cells Minor scar More function ```
300
What factors influence healing?
Infection Separation Foreign bodies Affected by extent of injury and tissue loss
301
What factors are required for healing?
``` Nutrition O2 Blood flow Immune function Inflammatory function ```
302
Difference between primary intention and secondary intention?
Primary is minor damage | Second is major damage
303
What is included on a Full Blood Count (FBC)?
``` Red cells (description of cells) White cells (+subtypes) Platelets ```
304
How to send a FBC?
EDTA sample to haematology lab
305
Describe the structure of a neutrophil?
Multi-lobed nucleus | Granular cytoplasm
306
Describe the structure of a eosinophil?
Multi-lobed and granular | Increased in allergy, inflamm and myeloproliferative disease
307
When are basophil found in the blood, in response to?
Increased in allergy and myeloproliferative disorders
308
Describe the structure of a monocyte?
Larger | Lobulated nuclei
309
What to double check if platelets are very low?
Check for platelet clumping on the blood count
310
Male Hb reference range for 12-70 yo?
140-180 g/L
311
Male Hb reference range for >70 yo?
116-156 g/L
312
Female Hb reference range for 12-70 yo?
120-160 g/L
313
Male Hb reference range for >70 yo?
108-143 g/L
314
What is the definition of anaemia?
Reduction in red cells or their haemoglobin content
315
Name 4 causes of aneamia?
Blood loss Increased destruction Lack of production Defective production
316
Describe the signs and symptoms of anaemia?
Tiredness/Fatigue Dizziness/Lightheadedness Breathlessness (on exertion) Chest pains Pale Glossitis Angular stomatitis Koilonychia (spoon-shaped nails) Due to oxygen deprivation
317
What does MCV stand for?/
Mean cell volume (cell size)
318
What does MCH stand for?
Mean cell haemoglobin
319
Diagnosis for Low MCV and MCH and and a further test?
Hypochromic microcytic Test for Serum ferritin (low)
320
Diagnosis for Raised MCV and a further test?
Macrocytic Test for B12/Folate and bone marrow (low)
321
Name 4 causes of hypochromic microcytic anaemia?
``` Blood loss Increased requirements Reduced intake Normal ferritin (Thalassaemia) Anaemia of chronic disease ```
322
Name 4 causes of macrocytic (megaloblastic) aneamia?
``` B12: - autoimmunity (pernicious anaemia) - binds to intrinsic factor which has autoantibodies against them - gastric disease Folate: - dietary - malabsorption - increased requirements Myelodysplasia Liver disease Drugs Alcohol Thyroid disease ```
323
Diagnosis for normal MCV and MCH and a further test?
Normochromic normocytic anaemia | Reticulocyte count
324
Diagnosis for a low/normal reticulocyte count?
Marrow replacement Hypoplasia (secondary anaemia)
325
Diagnosis for a increased reticuloycte count?
Acute blood loss | Haemolysis
326
Describe what occurs for haemolytic anaemia?
Accelerated red cell destruction Compensation by BM (increased reticulocytes) Level of Hb balance between red cell production and destruction
327
How long does a RBC last in the circulation?
120 days
328
How are RBCs broken down?
By the reticuloendothelial system
329
What are RBCs broken down into?
Globin Iron Protoporphyrin
330
What does globin get converted into?
Amino acids
331
What does iron get converted into?
Binds to transferrin
332
What does protoporphyrin get converted into?
Bilirubin Transported to liver Bound to glucuronides Excreted in urine as urobilinogen or in the faeces as stercobilinogen
333
Name 3 types of congenital haemolytic anaemia and tests for their diagnosis?
``` Hereditary spherocytosis (HS) Enzyme deficiency (G6PD) Haemoglobinopathy (HbSS) ```
334
Name the acquired types fof haemolytic anaemia?
Autoimmune haemolytic anaemia (extravascular)
335
Name 3 intravascular acquired types of haemolytic anaemia?
Mechanical (valve) Severe infection PET/HUS/TTP
336
Describe the signs and symptoms of haemolytic anaemia?
Jaundice | Yellow sclera
337
Explain the mechanism of action for Warfarin?
Orally active vitamin K antagonist Reduces functional factors II, VII, IX and X Monitored by INR
338
Indications for Warfarin?
Atrial fibrillation Prosthetic heart valves Other arterial thromboembolism Venous thromboembolism
339
What are the disadvantages for warfarin?
``` Wide individual variation in dose to achieve target INR High drug inters Dietary inters (vit K rich food) Fatal bleeding 1% per year ```
340
What is warfarin target enzyme and what is it metabolised by?
Vit K epoxide reductase | P450
341
What is warfarin target INR?
2.0-3.0 Can go up to 3.0-4.0 In therapeutic range for 60%
342
What are the considerations a dentist must take when a patient on warfarin attends the surgery for an extraction?
INR <4.0 dental procedures are allowed Oxidised cellulose, collagen sponges and sutures can be considered 5% tranexamic acid mouthwash for 2 days can be considered Avoid NSAIDs IANB - anecdotal risk of bleeding with airway compromise (INR >3.0) Single dose antibiotic prophylaxis unlikely to affect INR
343
Name the immediate and gradual reversal of warfarin?
Immediate: - coagulation factor concentrate (II, VII, IX and X), Intravenous Gradual: - vitamin K, PO/IV
344
Explain the mechanism of action for heparin?
Inhibits thrombin and F Xa indirectly
345
Indications for heparin?
Prophylaxis of venous thrombosis Treatment of arterial and venous thrombosis Need interruption of treatment at least 24hrs pre procedure
346
Describe what the ideal antithrombotic drug should do?
``` Orally active Predictable dose-response No monitoring required Minimal drug inters minimal effect of diet ```
347
Name 3 new Anti-Xa oral anticoagulants?
Rivaroxaban (3A4 and 2J2) Apixaban (3A4) Edoxaban (3A4)
348
Name 1 new antithrombin oral anticoagulant
Dabigatran
349
Explain the mechanism of action for Dabigatran?
Inhibits thrombin Metabolised in the liver Excreted via the kidneys
350
Explain the mechanism of action for new Anti-Xa anticoagulants?
Metabolised by the Liver | Excreted via faeces and kidney
351
What to suggest to patients on DOACS for a low and high bleeding risk procedures?
``` Low: - treat without interruption High: - omit dose on morning of procedure - omit for longer (48/72) if have renal disease ```
352
Explain the mechanism of action for aspirin?
Irreversible inhibitor of platelet COX reduce platelet aggregability Impairs primary haemostasis
353
Explain the mechanism of action of Clopidogrel/Ticagrelor/Prasugrel?
Block the platelet ADP receptor (P2Y12)
354
Explain the mechanism of action of dipyridamole?
Blocks platelet phosphodiesterase and adenosine deaminase
355
Indications for aspirin?
For secondary prophylaxis of arterial thrombosis Used in combo with: - dipyridamole in stroke - clopidogrel after coronary intervention - rivaroxaban in peripheral/coronary artery disease
356
How long do aspirin's effects last for?
7 days
357
How long do clopidogrel effects last for?
over 5 days
358
What should you advice to a patient taking anti-platelet drugs for a extraction?
Treatment should be fine without interruption of drug as the risk/benefit to stopping the drug is much higher risk
359
Name the 2 causes of reduced survival for thrombocytopenia?
Immune thrombocytopenic purpura | Drug induced
360
Name the 5 causes of reduced production for thrombocytopenia?
``` Chemotherapy Bone marrow malignancy/failure Megaloblastic anaemia Drug induced Alcohol excess ```
361
What is the normal platelet count?
>140 x10^9/L
362
What is the mild thrombocytopenia platelet count?
80-140 x10^9/L
363
What is the moderate thrombocytopenia platelet count?
20-80 x10^9/L Increased bleeding after trauma
364
What is the severe thrombocytopenia platelet count?
<20 x10^9/L Severe bleeding after trauma
365
Platelet count threshold for simple elective procedures?
>20
366
Platelet count threshold for simple extraction?
>30
367
Platelet count threshold for complex extraction?
>50
368
Platelet count threshold for LA?
>30 | Avoid IAN
369
Platelet count threshold for Minor oral surgery?
>50
370
Platelet count threshold for major oral surgery?
>80
371
Describe Immune thrombocytopenic purpura?
``` Autoimmune Against platelets Triggered by infection or meds Variable severity Responsive to immunosuppressants or splenectomy ```
372
What coagulopathy are associated with liver disease?
All clotting factors and fibrinogen are reduced | Enlarged spleen due to portal hypertensions leads to thrombocytopenia
373
Reduced clotting factor + thrombocytopenia = ?
Bleeding
374
Reduced natural anticoagulants = ?
Thrombosis
375
How to manage patients with liver disease?
Striking balance between preventing bleeding and thrombosis | Often avoid replacement of clotting factors unless hemorrhagic
376
Signs and symptoms of acquired haemophilia?
New onset bruising No previous bleeding disorder history Isolated prolonged APTT and low levels of VIII Antibody to VIII
377
Management of acquired haemophilia?
``` Bypassing agents (Novoseven) to control bleeding episodes Immunosuppression with high dose steroid (+/- cyclophosphamide) Refractory cases may require B cell depletion with Rituximab ```
378
Vitamin C deficiency can cause acquired bleeding disorder?
``` Yes Cofactor in collagen synthesis Require 40mg daily Smokers need more Can lead to scurvy ```
379
Signs and symptoms of scurvy?
``` Normocytic anaemia Bleeding with normal platelets and coagulation Skin and gum changes High risk: - alcoholics - malignancy ```
380
What are the risk factors for essential hypertension?
``` Obesity Alcohol Salt intake Stress Genetics ```
381
What is the definition of secondary hypertension?
Due to other diseases such as kidney dysfunction or hormonal disturbances
382
Explain how to manage a patient with high BP?
Weight loss Low salt diet Moderation of alcohol intake If risk too high pharmacological measures are indicated
383
Blood pressure value to be diagnosed with hypertension?
>160/100 mmHg Treatment
384
``` Blood pressure value to be diagnosed with borderline hypertension (High CV risk)? ```
140-159/90-99 mmHg Treatment
385
``` Blood pressure value to be diagnosed with borderline hypertension (High CV risk)? ```
140-159/90-99 mmHg Lifestyle changes
386
What is the definition of postural hypotension?
Where one's BP falls on standing up with subsequent brief loss of consciousness This is especially seen when a patient gets up from the dentist's chair Can be further exacerbated with the use of sedation during dental procedures
387
What antihypertensive drug causes gingival overgrowth?
Some Ca channel blockers such as nifedipine
388
What BP reading will make dental treatment not suitable?
180/110 mmHg
389
What recommendations would you give to a hypertensive patient needing a dental procedure in the future?
hypertensive patients take their medication on the day of the dental procedure and have their BP checked a few minutes following injection. Always seek medical advice where there is any concern.
390
What is the definition of stable angina?
Angina is a temporary obstruction of blood flow to the heart, with no associated damage to the myocardium. This typically presents as chest pain radiating to the jaw or left arm that resolves within minutes. Where pain occurs with exercise, this is known as 'stable angina'.
391
What is the definition of unstable angina?
Where pain is experienced at rest or on minimal exertion, this is 'unstable angina'.
392
What is the definition of ischaemic heart disease?
Occurs when there is inadequate blood supply and, hence, oxygen supply to the heart muscle.
393
What is the definition of myocardial infarction?
Myocardial infarction is a complete obstruction of blood flow to the myocardium leading to muscle death. This presents as angina-like pain that is more severe and persistent and is associated with nausea, vomiting and shortness of breath. The patient is often pale and clammy
394
What are the risk factors for Ischaemic heart disease?
Age Gender Genetics ``` Hypertension High cholesterol Diabetes Obesity Excess alcohol consumption ```
395
Explain the development of an atherosclerotic plaque in a coronary artery?
Develop at sites of pre-exisiting arterial wall damage caused by hypertension smoking or high blood cholesterol Fatty plaques become large enough to occlude vessel Plaque also promotes thrombus development leading to complete occlusion
396
What modifiable risk factors can a patient with IHD reduce?
``` Exercise with a balanced diet Smoking cessation BP control DIabetes control Reduction of cholesterol ```
397
Name 3 drugs that are indicated for MI, and angina?
Aspirin Statins ACE inhibitors
398
Describe the mechanism of action for aspirin?
By inhibiting circulating platelets from forming a clot, preventing obstruction of the arteries
399
Describe the mechanism of action for statins?
Reduce LDLs | Inhibiting HMG-CoA reductase
400
Describe the mechanism of action for ACE inhibitors?
Inhibiting the enzyme ACE
401
What surgical intervention is GS for treatment of IHD?
Percutaneous angioplasty Insertion of a stent via a peripheral artery into a stenosed coronary artery If this fails, a coronary artery bypass graft can be undertaken (from patient's leg)
402
How long should treatment be avoided after an acute MI?
6 months
403
What is the definition and symptoms of congestive heart failure?
This is the situation where the oxygenated blood pumped out from the heart is inadequate to meet the metabolic demands of the body. This mismatch can result in a variety of symptoms, the commonest being fluid retention in dependent areas such as the legs and, more significantly, in the lungs. Patients subsequently have difficulty breathing, and are unable to lie flat. They have poor exercise tolerance, also limited by difficulty breathing. In the severest form, patients are short of breath at rest and are unable to mobilise at all.
404
What medications are indicated for HF and their aims?
``` Diuretics (loop) - remove extra fluid ACE inhibitors (promote cardiac function) B-blockers (promote cardiac function) ```
405
What are the dental implications for a patient with HF?
Difficulty lying flat | If uncontrolled, avoided unless an emergency
406
Name 2 analgesics to be wary when prescribing for a patient with kidney or liver problems?
NSAIDs | Opioids
407
Why you need to be wary when prescribing for a patient with kidney or liver problems?
Dosages are metabolised at different rates due to the loss of function can exacerbate disease and have higher levels in the blood
408
How can NSAIDs cause damage?
Direct damage to kidneys with long-term use | Cause fluid retention exacerbating HF symptoms straining the myocardium
409
How can opioids cause damage?
Avoid morphine as liver damaged individuals can lead to drug accumulation
410
What is the definition of an ECG?
The electrocardiograph (ECG) is a trans-thoracic interpretation of the electrical activity of the heart.
411
What does the P wave represent?
Atrial contraction
412
What does the PR interval represent?
Passage of electrical current between atria and ventricles
413
What does the QRS complex represent?
Ventricular contraction
414
What does the T wave represent?
Ventricular relaxation
415
What's the definition of a cardiac arrhythmia?
occur when there is an abnormality within the cardiac conduction system. They may manifest as dizziness, palpitations, collapse, shortness of breath or sudden cardiac death. There may be no symptoms at all.
416
Bradycardia?
<60 bpm
417
Tachycardia?
>100 bpm
418
When can sinus bradycardia be seen?
Sinus bradycardia is often seen in athletes; it may also be seen in patients with hypothermia or hypothyroidism.
419
When can sinus tachycardia be seen?
Experienced during exercise. It is also seen with fever and in hyperthyroidism.
420
What is the definition of atrial fibrillation?
It occurs when electrical activity within the atria becomes disordered and chaotic. Consequently, the muscle fibres of the atria no longer contract in synchrony; instead they 'fibrillate' making the atria mechanically ineffective.
421
How does AF look on an ECG?
Lack of P waves and by an irregularly irregular ventricular rate`
422
What are the signs and symptoms for a patient presenting with AF?
``` Palpitations Shortness of breath Collapse DIzziness Fatigue ```
423
Name 5 conditions that can cause AF?
``` ISH Rheumatic HD Hypertension Mitral valve disease Cardiomyopathy ```
424
How to manage a patient withAF?
Rhythm control: - cardioversion with shocking or amiodarone/flecainide Rate control: - via b blockers (bisoprolol and digoxin) Stroke prevention: - anticoagulation such as warfarin
425
What is the definition of heart block?
occurs when there is a delay in the conduction of electrical current as it passes through the cardiac conduction system
426
What are the signs and symptoms for heart block?
Many symptom free Fatigue Dizziness Collapse
427
Name the 2 types of heart block?
AV block | Bundle branch block
428
What is the definition of AV block?
Block at the level of the AV node
429
What is the definition of bundle branch block?
There is an abnormality lower down in the conducting system
430
Name the 3 degrees of heart block?
1st 2nd 3rd
431
Describe 1st degree heart block and ECG findings?
when there is delayed electrical conduction to the ventricles following atrial activation. However, every impulse reaches the ventricles. Prolonged PR interval
432
Describe 2nd degree heart block and ECG findings?
Occurs when there is intermittent block of impulses to the ventricles. The heart may beat slowly, irregularly or both.
433
Name the 2 types of 2nd degree heart block?
Mobitz 1 | Mobitz 2
434
How does Mobitz 1 show via ECG?
Failed conduction of QRS complex due to progressive elongation of PR interval
435
How does Mobitz 2 show via ECG?
Dropped QRS complex | 2 P waves to a single QRS complex
436
Describe 3rd degree heart block and ECG findings?
Occurs when there is complete failure of conduction to the ventricles from the atria. Life is maintained by so called 'escape rhythms' generated in conducting tissue within or distal to the AV node. This results in a very slow heart rate There is no relationship between P waves and QRS complexes and the ventricular rate is slow.
437
Aetiology of First degree heart block?
Athletes and young patients Structural heart disorders Drugs
438
Aetiology of Second degree heart block?
Young people Athletes Structural abnormalities Acute myocardial infarction
439
Aetiology of Third degree heart block?
Complete heart block Elderly (degenerative) Young patients (ischemic)
440
Treatment for first degree heart block?
Rarely warranted
441
Treatment for 2nd and 3rd degree heart block
Artificial pacemaker
442
What is the definition of bundle branch block?
Occurs when there is complete or incomplete interruption to the flow of electrical current through the right or left bundle branches
443
What is the difference between right and left bundle branch block?
Right: - healthy individuals as an isolated congenital abnormality - result from cardiac or respiratory condition - damage to heart Left: - more severe - from IHD, aortic valve disease or secondary to chronic hypertension
444
Name the 12 complications of hypertension?
``` Haemorrhage Stroke Cognitive decline Retinopathy Peripheral vascular disease Renal failure Dialysis Transplantation Left ventricular hypertrophy HF CHD MI ```
445
How does IHD and stroke risk change with a 2 mmHg rise in BP?
7% for IHD | 10% for stroke
446
At what BP is a patient hypertensive?
NICE: 140/90
447
What is the definition of Stage 1 hypertension?
Clinic blood pressure is 140/90 mmHg or higher | ABPM daytime average 135/85 mmHg or higher.
448
What is the definition of Stage 2 hypertension?
Clinic blood pressure is 160/100 mmHg or higher | ABPM daytime average 150/95 mmHg or higher.
449
What is the definition of Severe hypertension?
Clinic systolic blood pressure is 180/120 mmHg or | higher
450
Name the 7 risk factors for hypertension?
``` Cigarette smoking Diabetes Renal disease Male Hyperlipidemia Previous MI/Stroke Left ventricular hypertrophy ```
451
How is BP controlled systemically?
By an integrated system of the | sympathetic and renin angiotensin aldosterone systems.
452
What occurs during activation of the sympatheic nervous system of the heart?
Vasoconstriction Reflex tachycardia Increased CO All increasing the BP
453
When is the Renin-angiotensin-aldosterone system stimulated?
Fall in BP Fall in blood volume Na depletion
454
What is the aetiology of hypertension?
Polygenic: - major and poly genes Polyfactorial: - environment
455
Name 2 theories on hypertension aetiology?
Increased reactivity of resistance vessels and resultant increase in peripheral resistance – as a result of an hereditary defect of the smooth muscle lining arterioles • A sodium homeostatic effect – In essential hypertension the kidneys are unable to excrete appropriate amounts of sodium for any given BP. As a result sodium and fluid are retained and the BP increases
456
Name 9 risk factors that contribute to hypertension?
``` Age Genetics Environment Weight Alcohol intake Race Birth weight Na intake ```
457
Name the 2 types of hypertension?
Primary | Secondary
458
What is the definition of secondary hypertension and its causes?
``` Caused by other disease Renal disease Drug induced Pregnancy (pre-eclampsia) Endocrine Vascular (coarctation of aorta) Sleep Apnoea ```
459
Name 4 types of renal disease that cause 2nd HT?
Chronic pyelonephritis Fibromuscular dysplasia Renal artery stenosis Polycystic kidneys
460
Name 3 types of drug inducers of 2nd HT?
NSAIDs Oral contraceptive Corticosteroids
461
Name 6 types of endocrine causes of 2nd HT?
``` Conn’s Syndrome – Cushing's disease – Pheochromocytoma – Hypo and hyperthyroidism – Acromegaly ```
462
How to accurately diagnose HT?
Must use ABPM Ambulatory Blood pressure Monitoring – or HBPM Home Blood pressure Monitoring
463
HT risk calculator?
assign-score.com
464
BHS target pressure to reach?
<135/80-85 mmHg
465
Why do we treat hypertensive patients?
reduce cerebrovascular disease by 40-50% | – reduce MI by 16-30%
466
How do we approach treatment for hypertensives?
Stepped approach Low doses of several drugs Minimises adverse events and maxismises patient compliance
467
BIHS guidelines for young and elderly patient with HT?
``` Young: - ACE inhibitor or ARB Elderly: - Ca ch blocker - Thiazide (diuretic) ```
468
Step 1 treatment for a HT patient?
<55 offer ACE inhibitor/ARB contraindicated for afro-caribbean and women of childbearing age (avoid teratogenicity) (low renin state and a lower cardiac output, with increased peripheral resistance)
469
Step 2 treatment for a HT patient?
Add thiazide diuretic such as indapamide to CCB or ACEI/ARB
470
Step 3 treatment for a HT patient?
Add CCB, ACEI and diuretic together
471
Name 3 ACE inhibitors?
Ramipril Perindopril Lisinopril
472
Contraindications of ACE inhibitors?
Renal artery stenosis Renal failure Hyperkalaemia
473
ADR of ACE inhibitors?
``` Cough First dose hypotension Taste disturbance Renal impairment Angioneurotic oedema ```
474
Name 3 types of ANG II antagonists (ARB)?
Valsartan Candesartan Irbesartan Similar sides and nters No cough
475
Name 4 types of Ca ch blockers?
``` Vasodilators: - amlodipine - felodipine Rate limiting: - verapamil - diltiazem ```
476
Contraindications of Ca ch blockers?
Acute MI Heart failure Bradycardia (rate limiting CCBs)
477
ADRs of CA ch blockers?
``` Flushing Headache Ankle oedema Indigestion Reflux oesophagitis ``` Also cause bradycardia and constipation
478
Name 2 thiazide type diuretics?
``` Indapamide Chlorthalidone 1st line for afro-caribbean Can be combo Help in stroke and MI ```
479
Mechanism of action for thiazide diuretics?
Urinary excretion of Na
480
ADRs of thiazide diuretics?
Gout | Impotence
481
Name 1 alpha antagonist for HT?
Doxazosin
482
Name 2 centrally acting agent for HT?
Methyldopa | Moxonidine
483
Name 2 vasodilators for HT?
Hydralazine | Minoxidil
484
Mechanism of action for doxazosin?
Selectively block postsynaptic alpha 1-adrenoceptors | Oppose vascular smooth muscle contraction in arteries
485
ADRs of Doxazosin?
First dose hypotension Dizziness Dry mouth Headache
486
Indications for methyldopa?
HT in pregnancy
487
Mechanism of action for methyldopa?
Converted to alpha-methylnoradrenaline which acts on CNS alpha adrenoceptors which decrease central sympathetic outflow
488
ADRs for methyldopa?
``` Sedation Drowsiness Depression Dry mouth Nasal congestion Orthostatic hypotension ```
489
Mechanism of action for moxonidine?
Centrally acting imidazoline agonist
490
Describe the treatment regimen for patient over 55 YO?
``` CCB + thiazide diuretic + ACE inhibitor + Beta blocker + less commonly used agent ```
491
Describe the treatment regimen for patient under 55 YO?
``` ACE inhibitor Childbearing age CCB or beta blocker + thiazide diuretic + CCB + b-blocker + less commonly used agent ```
492
What interactions can occur between HT and pregnancy?
Develop gestational HT Sometimes BP rises severely from about 20 weeks BP>140/90 mmHg and proteinuria >300 mg/24h --- Preeclampsia
493
Treatment for HT pre-pregnancy?
Nifedipine Methyldopa Atenolol Labetalol
494
Treatment for HT during pregnancy?
+ thiazide diuretic | + amlodipine
495
Potential complications for hypertensive pregnant women?
``` Postural hypertension Renally impaired Bradycardia Collapse Drug inters ```
496
What is the clinical value for a anaemic patient?
< 13.5 g/dl in M | < 11.5 g/dl in F
497
What are the signs and symptoms of anaemia?
``` Fatigue Headaches Loss of appetite Weight loss Breathlessness Pale skin Increased HR Nausea ```
498
What are the oral symptoms of anaemia?
``` Angular cheilitis Glossitis Burning mouth/tongue Aphthous ulcer Oral candidiasis Delayed wound healing ```
499
Name 5 causes of normocytic anaemia?
``` Cancer RA IBS Renal problems TB ```
500
What is the definition of microcytic?
Red cell is <80 fl in size and is usually associated with reduced intra-cellular haemoglobin (Hb), which creates a hypochromic appearance
501
What is the definition of macrocytic?
Reflects an increased MCV but with reduced Hb level
502
What is the definition of normocytic?
The Hb is low but the MCV is within normal limits
503
Name 4 causes of microcytic anaemia?
Iron deficiency Anaemia of chronic disease Sideroblastic anaemia Thalasseamia
504
How is iron absorbed via the GI?
Absorbed in the duodenum in acidic conditions and carried in the blood as transferrin but stored in the marrow, liver and muscle as ferritin
505
Name 5 common causes of iron deficiency anaemia?
``` Period GI blood loss Increased demand Small bowel disease Poor diet ```
506
What is the FBC diagnosis for iron deficiency anaemia?
Low Hb and low MCV Low ferritin Total iron binding capacity is increased
507
What is the management for iron deficiency anaemia?
Treat cause Oral iron (Ferrous sulphate) IM
508
Name the 2 types of Thalassaemia?
Alpha | Beta
509
Name the 3 types of Beta Thalassaemia?
Major Intermedia Minor
510
What causes megaloblastic anaemia?
Vit b12 deficiency | Folate deficiency
511
Name the 6 main reasons for B12 deficiency?
``` Pernicious anaemia Gastrectomy Vegan Ileal resection Coeliac disease Bacterial overgrowth ```
512
Name the 4 main reasons for folate deficiency?
Diet Malabsorption High demand Drugs
513
What is the definition of sickle cell anaemia?
Inheritance of a gene for HbS, sickle haemoglobin. This is needed for the exchange of valine for glutamic acid in position 6 of the Hb beta chain
514
What is the role of G6P dehydrogenase?
Glucose-6-phosphate dehydrogenase deficiency is vital to maintain glutathione in a reduced state to help the movement of electrons (H) through the metabolic pathways (oxidation)
515
Blood group O - serum abs and info?
Anti A and B | Universal donor
516
Blood group A - serum abs and info?
Anti B
517
Blood group B - serum abs?
Anti A
518
Blood group AB - serum abs and info?
None | Universal recipients
519
Name 6 respiratory symptoms?
``` Breathlessness Cough Sputum Haemoptysis Chest pain Wheeze ```
520
What assessments would a dentist carry out to assess respiratory disease?
Pulse oximetry Pulse rate Respiratory rate Peak flow meter
521
What is the definition of TI respiratory failure and give 2 examples?
Low PO2 Normal or low PCO2 Acute asthma Pneumonia
522
What is the definition of TII respiratory failure and give 2 examples?
Low PO2 High PCO2 COPD Obesity hypoventilation syndrome
523
Signs and symptoms for asthma and COPD?
Breathlessness Wheeze Cough
524
What is the difference between COPD and asthma?
COPD: - irreversible airflow obstruction Asthma: - reversible airflow obstruction
525
What tests can be carried out to help diagnose asthma and COPD?
History Peak flow recording Lung function
526
Name the 5 treatment options for Asthma and COPD?
``` Inhaled bronchodilators (salbutamol) Inhaled corticosteroids (beclomethasone) Oral theophylline Oral leukotriene receptor antagonist (montelukast) Oral prednisolone ```
527
What is the definition of pneuomina?
Infection of the lower respiratory tract
528
What are the signs and symptoms of pneumonia?
``` Fever Myalgia Headache Cough Chest pain Sputum Dyspnoea ``` Can proceed to TI respiratory failure
529
What are the treatment for pneumonia?
Antibiotics Oxygen intravenous fluids
530
What is the definition of obstructive sleep apnoea?
Loud snoring and cessation of breathing Daytime sleepiness Poor concentration
531
How to treat obstructive sleep apnoea?
Weight loss CPAP Mandibular repositioning splint
532
What is the definition of a pulmonary embolism?
Blood clot in the lungs, that typically arises in the leg veins
533
Name 4 risk factors for pulmonary embolism?
Recent major operation Recent major trauma Immobility Major chronic disease
534
What are the signs and symptoms of pulmonary embolism?
Breathlessness Chest pain Haemoptysis
535
What is the treatment for pulmonary embolism?
Anticoagulation
536
What is the definition of a pneumothorax?
Collapsed lung
537
Name the 2 types of pneumothorax?
Primary | Secondary
538
Signs and symptoms for a pneumothorax?
Chest pain | Dyspnoea
539
How to treat a patient with pneumothorax?
Aspiration of air around collapsed lung Observation Chest drain
540
Signs and symptoms for lung cancer?
Cough Haemoptysis Weight loss
541
What is the definition of a chronic cough?
Cough lasting longer than 8 weeks
542
Name 3 common causes of chronic cough?
Asthma Gastro-oesophageal reflux Postnasal drip
543
What is the definition of bronchiectasis?
Dilated and damaged airways
544
Signs and symptoms of bronchiectasis?
Cough Large amount of sputum Haemoptysis
545
What are the treatment options for chronic cough/
Inhaled corticosteroids gastric acid suppression (omeprazole) Intranasal steroid spray (beconase)
546
How to diagnose sleep apnoea?
Sleep study
547
How to diagnose lung cancer?
CT scan | Bronchoscopy
548
How to diagnose chronic coughing?
Lung function test
549
How to diagnose bronchiectasis?
CT thorax
550
What is the definition of interstitial lung disease?
Thickening, inflammation of interstitium of the lung
551
Signs and symptoms of interstitial lung disease?
Dyspnoea | Dry cough
552
How to diagnose interstitial lung disease?
CT scan
553
Treatment options for interstitial lung disease?
Corticosteroids Oxygen Pulmonary rehab Pirfenidone
554
Explain the process of the platelet plug?
Vessel damage leads to platelet adhesion to the VWf Platelets then aggregate to other platelets to form a plug + some fibrinogen Fibrinogen is hen broken down to form fibrin forming the clot
555
What is the intrinsic pathway for clotting?
``` IX --> IXa IXa --> X via VIIIa X --> Xa Prothrombin --> Thrombin via Xa Fibrinogen --> Fibrin by thrombin ```
556
What is the extrinsic pathway for clotting?
``` VII + Tissue factor VIIIa/TF --> Xa X --> Xa Prothrombin --> Thrombin via Xa Fibrinogen --> Fibrin by thrombin ```
557
Name 4 pathological causes for bleeding disorders?
Decreased number of platelets Abnormal platelet function Von Willebrand disease Coagulation factor (deficiency or inhibition)
558
Name 5 points to think about when gauging bleeding history?
``` Do you have a bleeding disorder? How severe is the disorder? Pattern of bleeding Congenital or acquired Mode of inheritance ```
559
Name 6 times history of bleeding can give information?
``` Bruising Epistaxis Post-surgical bleeding Menorrhagia Post-partum haemorrhage Post-trauma ```
560
Name 5 types of platelet type of pattern of bleeding?
``` Mucosal Epistaxis Purpura Menorrhagia GI ```
561
Name 3 types of coagulation factor for pattern of bleeding?
Articular Muscle haematoma CNS
562
How to determine the difference between acquired and congenital?
Previous episodes Age at first event Previous surgical challenges Associated history
563
What is the definition of Haemophilia A and B?
X-linked Identical phenotypes Severity of bleeding depends on the residual coagulation factor activity
564
What are the clinical features of haemophilia?
``` Haemarthrosis Muscle haematoma CNS bleeding Retroperitoneal bleeding Post surgical bleeding ```
565
What questions to ask a dental patient with a suspicion of bleeding disorders?
Do you have a history of bleeding disorder? Do you have a family history of bleeding? Have you had any previous operations? Are you taking any anticoagulant drugs?
566
What advice is given for severe haemophilia for dental procedures?
Enhanced preventive GDP | All treatments except prosthetics in specialist hospital setting
567
What advice is given for moderate haemophilia for dental procedures?
Enhanced preventive GDP | All treatments except prosthetics specialist hospital setting
568
What advice is given for mild haemophilia for dental procedures?
Enhanced preventive advice and treatment GDP Many procedures at GDP 2 yearly review specialist dental centre
569
What treatment should a haemophiliac +ve patient have for dental management?
``` Prevention as normal Mild Haem A: - DDA VP/tranexamic acid Mod/Severe Haem A: - coagulation factor replacement for VIII All Haem B: - coagulation factor replacement ```
570
What dental LA procedures require factor elevations?
IAN | Lingual infiltration
571
What dental LA procedures DO NOT require factor elevations?
Buccal infiltration Intrapapillary injection Intraligamentary injections
572
What adjunctive to treatment is useful for bleeding disorder patient?
Suturing and local haemostatic measure for extractions | Resorbable and non-resorbable sutures acceptable
573
Name 8 local haemostatic agents?
``` Oxidized cellulose Surgicel Absorbable gelatine sponge Gelfoam Cyanoacrylate tissue adhesives Surgical splints Lyostypt Ankaferd blood stopper ```
574
Hwat complications can occur with haemophilia treatment?
``` Viral infections: - HIV, HBV and HCV Inhibitors - DDAVP Flushing Rare arterial events Hyponatremia in babies ```
575
What is the definition of Von Willebrand disease?
``` Common Variable severity Autosomal Mucosal platelet bleeding type Quantitative and qualitative abnormalities of vWF ```
576
What precautions should you advice to a Von willebrand disease patient before treatment?
vWF concentrate or DDAVP Tranexamic acid Topical applications
577
Name the 4 valves of the heart?
Pulmonic Aortic Bicuspid Tricuspid
578
Name the 3 types of valvular heart disease?
Valvular stenosis Valvular regurgitation Aortic coarctation CHD
579
What does the aortic valve look like?
Inverted Merc badge
580
Name the 2 types of aortic stenosis?
Degenerative | Bicuspid
581
What is the aetiology of degenerative aortic stenosis?
Becomes thick and calcified | Can fuse in the future
582
What is the aetiology of bicuspid aortic stenosis?
2 leaflets rather than 3 leaflets
583
Name 3 symptoms of aortic stenosis?
Chest pain Breathlessness on exertion Syncope/Dizziness
584
Name the 2 types of causes of aortic regurgitation
Aortic defects | Leaflet defects
585
How can the aorta cause aortic regurgitation?
Dilated aorta
586
How can the leaflets of the aortic valve cause aortic regurgitation?
Bicuspid Rheumatic heart disease Endocarditis
587
Explain how Rheumatic heart disease occurs?
Occurs from primary infection that leads to cross-abs to heart structure
588
Name the 2 symptoms of aortic regurgitation?
Dyspnoea: - orthopnoea - paroxysmal nocturnal dyspnoea Chest pain
589
Name the 4 aetiologies for mitral valve disease?
``` Myxomatous degeneration (valves become redundant and elongated) Functional MR (enlarged ventricles, valves don't match up) Rheumatic heart disease Infectious endocarditis ```
590
Name the 3 symptoms for mitral valve disease?
Breathlessness Palpitations due to AF Embolisation
591
What is the definition of mitral stenosis?
Thickening and scarring of the leaflets | Fusion of the commissures
592
WHat is the definition of mitral regurgitation?
Leaflet abnormality | Mitral annular dilatation
593
Name the 2 right sided valves?
Tricuspid | Pulmonary
594
Name 2 types of congenital heart disease?
Ventricular septal defects | Compex CHD
595
Name 2 types of material for prosthetic heart valves?
Mechanical | Tissue
596
What medication must you be on if you have a mechanical heart valve?
Warfarin
597
How often should a blood INR be carried out?
Every 6 weeks
598
What is the INR for AF?
2-3
599
What is the INF for metallic heart valves?
2.5-4
600
How long should a tissue valve transplantee stay on anticoagulants for?
3 months
601
What to ensure about your patient with bleeding disorders before invasive treatments?
Ensure INR 2-4 72 hrs prior Ensure no other antiplatelet therapy (aspirin or clopidogrel) DO NOT prescribe NSAIDs or COX-2 inhibitors Ensure proper local haemostasis
602
What are the risks of stopping oral anticoagulation?
Small, but fatal
603
What is the definition of infective endocarditis?
Infection on the cardiac or vascular endothelium Forms vegetation Contains platelets, fibrin, microorganisms and inflammatory cell
604
Name the 2 predisposing factors and their subtypes for infective endocarditis?
``` Endothelium subjected to turbulent flow: - any valvaular or cardiac abnormality - prosthetic heart valves Bacteremia: - IV drug users - dental procedures - surgical procedures at infected sites ```
605
Name the 6 aetiologies for infective endocarditits?
``` Bacteria: - streptococcus - staphylococcus - enterococcus - pneumococcus - gram -ve bacilli Fungi Mycobacteria Rickettsiae Chlamydia Mycoplasma ```
606
Name the 7 signs and symptoms for infective endocarditis?
``` Fever Malaise Anorexia Weight loss HF due to acute valvular destruction Systemic embolisation Acute renal failure ```
607
What are the NICE guidelines for antibiotic prescription?
High risk patients when a high risk procedure is performed
608
What is the emphasis for dentists when treating patients with bleeding disorders?
Good oral hygiene | Regular dental review 2 yearly
609
Which patient count as a high risk patient for antibiotic prescription?
Prosthetic valve or prosthetic material used for cardiac valve repair Previous infective endocarditis CHD: - unrepaired cyanotic disease - complete repair up to 6 months after procedure - residual defects persists at the site of implantation of prosthetic material
610
What is the definition of a invasive dental procedure?
Procedures requiring the manipulation of the gingival or peri-apical region of the teeth or perforation of the oral mucosa including scaling and RCT)
611
What are the ESC 2015 guidelines for infective endocarditis prophylaxis?
``` No allergy: single dose 30-60 mins before procedure - amoxicillin or ampicillin - 2 g po/IV adult - 50 mg/kg po/IV child Allergy to penicillin: single dose 30-60 mins before procedure - clindamycin - 600 mg po/IV adult - 20 mg/kg po/IV ```
612
Which procedures do not need antibiotic prophylaxis for infective endocarditis/
LA injections in non-infected tissue (superficial caries) Removal of sutures Dental x-rays Placement or adjustment of removable orthodontic appliances or braces Shedding of deciduous teeth or trauma to the lips or oral mucosa
613
Name 11 invasive dental procedures?
Placement of matrix bands • Placement of sub-gingival rubber dam clamps • Sub-gingival restorations including fixed prosthodontics • Endodontic treatment before apical stop has been established • Preformed metal crowns (PMC/SSCs) • Full periodontal examinations (including pocket charting in diseased tissues) • Root surface instrumentation/subgingival scaling • Incision and drainage of abscess • Dental extractions • Surgery involving elevation of a mucoperiosteal flap or muco-gingival area • Placement of dental implants including temporary anchorage devices, mini implants • Uncovering implant sub-structures
614
Name 8 non-invasive dental procedures?
``` Infiltration or block local anaesthetic injections in non-infected soft tissues • BPE screening • Supra-gingival scale and polish • Supra-gingival restorations • Supra-gingival orthodontic bands and separators • Removal of sutures • Radiographs • Placement or adjustment of orthodontic or removable prosthodontic appliances ```
615
What dose of amoxicillin is needed for an adult with bleeding disorder patient prophylactically?
3g 60 mins before procedure
616
What dose of amoxicillin is needed for a child with bleeding disorder patient prophylactically?
Max dose 3g 50 mg/kg Oral suspension
617
What dose of clindamycin is needed for an adult with bleeding disorder patient prophylactically?
600mg 60 minutes before procedure
618
What dose of clindamycin is needed for a child with bleeding disorder patient prophylactically?
20 mg/kg | 600 mg max dose
619
What is consisted of the lower GI tract?
``` Jejunum Ileum Ascedning Colon Descedning colon Sigmoid colon Rectum Caecum ```
620
What is the function of the small bowel?
Enzymatic digestion absorption Gut hormone secretion Immune
621
What is the function of the large bowel?
Storage and elimination of waste | FLuid and electrolyte reabsorption
622
What are the symptoms for colorectal cancer?
Change in bowel habit Rectal blood loss Abdominal pain Weight loss Co-incidental anaemia
623
When does bowel cancer screening occur?
``` 50-74 YO Every 2 years Faecal occult blood Immunochemical test +ve result referral for colonoscopy 2% require colonoscopy ```
624
Explain how the adenoma can develop into a carcinoma?
Normal epithelium Small adenoma Large adenoma Invasive adenocarcinoma
625
What are the stages of colorectal cancer?
Dukes A-D
626
Dukes A?
Tumour confined to mucosa | 93% survival
627
Dukes B?
Extension through mucosa to muscle layer | 77%
628
Dukes C?
Extension through mucosa to muscle layer Involvement of lymph nodes 48%
629
Dukes D?
Distant spread | 7%
630
What is the surgical management for Dukes A?
Endoscopic resection possible for polyps Possible need for stoma if low rectal tumours or perforated or obstructed tumours
631
What is the genetic and environmental contribution for colorectal cancer?
Mainly sporadic Can be genetic Increased risk with IBD
632
What is the definition of familial adenomatous polyposis and its dental significance?
Autosomal dominant Mutation of APC gene High risk cancer Annual colonoscopy Supernumerary teeth Unerupted teeth Multiple osteomas of mandible (cotton wool like appearances)
633
What is the definition of Inflammatory bowel disease?
Chronic relapsing inflammatory conditions of the bowel UC and Crohn's Peak incidence in 20s
634
What is the aetiology for IBD?
Environmental Genetic Candidate genes identified
635
What are the triggering factors for IBD?
Bacterial infection Diet Vaccination history Social factors - smoking
636
Where does UC effect?
``` Continuous mucosal inflammation Affects the colon Rectum - proctitis Left sided hemi Extensive pan ```
637
What are the symptoms for UC?
Bloody diarrhoea Abdominal cramping Weight loss Malaise
638
What are the signs and symptoms of Crohn's disease?
``` Diarrhoea Bleeding Weight loss Vomiting Perianal symptoms ``` Fistula Abscesses Fissures
639
What are the signs and symptoms of Crohn's disease?
``` Diarrhoea Bleeding Weight loss Vomiting Perianal symptoms: - fistula - abscesses - fissures ```
640
What are the extra-intestinal manifestations for IBD?
Eyes: uveitis and conjunctivitis Joint: sacroiliitis, monoarticular arthritis and ankylosing spondylitis Liver: fatty, gallstones, pericholangitis and sclerosing cholangitis Skin: vasculitis, pyoderma gangrenosum and erythema nodosum
641
What is the definition of toxic megacolon?
Colonic dilatation and systemic toxicity due to severe flare of colitis
642
What is the definition of toxic megacolon?
Colonic dilatation and systemic toxicity due to severe flare of colitis
643
What is the medical treatment for IBD and their dental impact?
Immunosuppression Corticosteroids for acute flare ups Thiopurines (BM suppression) Biologics - infliximab (anti-TNF) Ensure no dental infection ongoing prior to administration
644
What is the definition of Coeliac disease?
Intolerance to gluten | Loss of microscopic villi in the SI, resulting in malabsorption
645
What are the symptoms for Coeliac disease?
Diarrhoea Weight loss Bloating Anaemia
646
Diet changes for coeliac +ve patient?
No: - bread - pasta - cake - cereals - sauces - pre-prepared meals - beer
647
What is the definition of small bowel infarction?
Acute mesenteric ischaemia Usually due to arterial thrombus or embolism blocking blood flow Rapid onset Emergency resection required
648
Name 2 eating disorders?
Anorexia nervosa | Bulimia nervosa
649
What is the definition of anorexia nervosa?
Refusal to maintain normal wight Fear of weight gain Distorted perception of body image
650
What's the definition of bulimia nervosa?
Binge eating followed by attempts to restrict weight gain | Purging
651
Oral manifestations for vomiting?
``` Palatal erosion Occlusal erosion of maxillary teeth: - incisal edges of incisors thin and knife-edged - cupped out appearance Swollen parotid glands ```
652
What is the definition of hereditary hemorrhagic telangiectasia?
Autosomal dominant Perioral telangiectasia Small bowel lesions can bleed Photocoagulation/embolisation/surgery
653
What is the definition of Peutz-Jeghers syndrome?
Autosomal dominant Mucocutaneous pigmented macules Multiple polyps throughout bowel (block or bleed) GI cancers risk hight
654
Oral manifestations for Crohn's disease?
``` Orofacial granulomatosis: - inflammatory condition affect the oral mucosa - found before Crohn diagnosis - non-caseating granulomas Recurrent mouth ulcers ```
655
Treatment for oral manifestations for Crohns?
Local/systemic corticosteroids | Cinnamon-free diet
656
What is the definition of diverticular disease?
Asymptomatic | Bulging sac of tissue protruding from colonic wall
657
Complications for diverticular disease?
Bleeding Perforation Infection + abscesses Require surgery High fibre diet good
658
Name 3 types of small bowel diseases?
Crohn's Coeliac disease Ischaemia/infarction
659
What are the symptoms of hereditary hemorrhagic telangiectasia?
Epistaxis | Pulmonary and cerebral lesions
660
Oral manifestation for iron-deficiency anaemia?
Angular cheilitis
661
What are the functions of the digestive system?
Digestion Secretion Absorption Motility
662
What is the sequence of organs that the food passes through?
``` Mouth Oesophagus Stomach SI Colon Rectum Anus ```
663
What organ is responsible for digestion?
Stomach
664
Which organ is responsible for absorption and secretion?
``` Absorption: - upper SI - colon Secretion: - lower SI - colon ```
665
Name the 2 forms of digestion?
Chemical | Enzymatic
666
Name each organ/tissue present in the GI tract?
``` Mouth Salivary glands Pharynx Trachea Oesophagus Liver Gallbladder Stomach Pancreas LI SI Rectum Anus ```
667
Describe the cross-sectional structure of the GI tract wall? Out to In
``` Serosa Longitudinal muscularis externa Myenteric plexus Circular muscularis externa Submucous plexus Submucosa (BVs and nerves) Mucosa (epithelium) Lumen ```
668
Name the 2 autonomic controls of the GI system?
Long (para) | Short (ENS) reflexes
669
Describe how the parasympathetic NS control the GI function during digestion?
``` Vagus nerve mainly Except salivation (VII and IX) Stimulatory: - increased secretion - increased motility ```
670
Describe how the sympathetic NS control the GI function during fight/flight?
Splanchnic nerve Inhibitor (except salviation): - reduced secretion - reduced motility
671
Where does the blood from the GI system drain to?
Hepatic portal vein
672
What 2 main vessels enter the Liver?
Hepatic portal vein | Hepatic artery
673
Why do we chew?
Prolong taste experience | Defence against respiratory failure
674
Explain the voluntary system in which chewing is controlled?
Somatic nerves innervate the skeletal muscles of the mouth and jaw
675
Explain the reflex pathway for chewing?
Contraction of jaw muscles leads to pressure of food against the gums, hard palate and tongue, activating mechanoreceptors that communicate to inhibit jaw muscles thus reduces the pressure causing contraction
676
Name the main organs for swallowing?
``` Hard palate Soft palate Tongue Epiglottis Glottis Larynx ```
677
Explain the oral phase (voluntary) during swallowing?
Bolus pushed to back of the mouth by tongue
678
Explain the pharyngeal phase during swallowing?
On presence of bolus it activates the sequence of reflex contractions of the pharyngeal muscles This is coordinated y the swallowing centre in the medulla The soft palate is reflected backwards and upwards (closing off the nasopharynx) As the bolus reaches the oesophagus the upper oesophageal sphincter relaxes and the epiglottis will cover the opening to the larynx stopping food entering the trachea Once bolus has entered the oesophagus the sphincter contracts (preventing reflux)
679
Explain the oesophageal phase during swallowing?
The propulsion of the bolus to the stomach Peristaltic waves sweep the bolus along the oesophagus and reaches stomach in 10s As the bolus nears the stomach the lower oesophageal sphincter relaxes allowing the bolus to enter the stomach Receptive relaxation of the stomach is initiated following relaxation of the sphincter and entry of bolus Vagal reflexes communicate to that there is relaxation of the thin, elastic SM of the gastric fundus and body
680
How does the size of the stomach change?
50mL --> 1500mL with no Pa change
681
Name the 3 main parts of the stomach?
Fundus Body Antrum
682
What allows the receptive relaxation of the stomach?
Rugae in the stomach
683
What is the function of the fundus?
Storage of material
684
What is the function of the body?
``` Storage Mucus HCl Pepsinogen Intrinsic factor ```
685
What is the function of intrinsic factor?
Binds B12 Aids haemoglobin formation Travels to terminal ileum and transported to the liver
686
What is the function of HCl and pepsinogen?
Digestion
687
What is the function of the antrum?
Mixing/grinding | Gastrin
688
What is the function of gastrin?
Regulates the secretion of HCl and pepsinogen
689
Name the 4 types of cells of a gastric gland?
Surface mucous Mucous neck Parietal Chief
690
What do mucous neck cells secrete?
Mucus
691
What do chief cells secrete?
Pepsinogen
692
What do parietal cells secrete?
HCl | Intrinsic factor
693
Name the 3 ways mechanism in which gastric acid is controlled?
Neurocrine (vagus) Endocrine (gastrin) Paracrine (histamine)
694
Explain the cepahlic phase of gastric acid secretion?
Sight, smell or taste of food witl activate the vagus nerve which activate parietal and g cells which release gastrin to further activate parietal cells Gastrin/ACh activate ECL cells which release histamine to further activate Parietal cells
695
Explain the gastric phase of gastric acid secretion
Distension of stomach after arrival of food stimulates the vagal and enteric reflexes releasing ACh activating the parietal cells Peptides present in the lumen activate G cells secreting gastrin will activate parietal cells Gastrin/ACh will activate ECL cells to release histamine and activate parietal cells
696
What cells produce pepsiongen?
Chief cells
697
How is pepsinogen activated?
pH of lover than 3 Acid hydrolysis and forms pepsin Pepsin continues to hydrolysis of pepsinogen
698
How is pepsinogen packaged?
Zymogens to stop cellular digestion
699
How are pepsin and HCl secretion related?
Proprotional to one another
700
What secrete gastic mucus?
Surface epithelial cells and mucus neck cells
701
What is the function of gastic mucus?
Cytoprotective role Protects mucosal surface from mechanical injury Neutralise pH as it has a high HCO content Protects against gastric acid corrosion and pepsin digestion
702
At what pH is pepsin denatured?
Neutral pH
703
Explain how acid is neutralised before entering the duodenum?
HCO secreted from Brunner's gland duct cells | H + HCO3 --> H2CO3 -> H20 + CO2
704
Explain how the duodenum controls the secretion of HCO3?
Long and short reflex for HCO3 secretion | Release of secretin from S cells increases HCO3 secretion
705
What does secretin activate the release of and from where?
HCO3 from pancreas and liver
706
How is secretin release controled?
Acid neutralisation leads to the inhibition of secretin release
707
What is the function of the duodenum?
To neutralise acid from the stomach
708
What duct enters the duodenum and the name of its sphincter?
Common bile duct | Sphincter of Oddi
709
Name the 2 types of cells of the exocrine pancreas?
Acinar cells | Duct cells
710
What do acinar cells secrete?
Digestive enzymes in zymogens
711
What is the function and location of enterokinase?
Brush border of duodenal enterocytes | Overt trypsinogen to trypsin
712
What is the function of trypsin?
Converts all zymogens to their active forms
713
What stimulates HCO3 secretion in the pancreas?
Secretin
714
What is secretin secreted in response to?
Acid in duodenum
715
What stimulates the release of zymogens from acinar cells?
Chlecystokinin
716
What is CCK secerted in response to?
Fat/aas in duodenum | Vagal reflex triggered by arrival of organic nutrients in the duodenum
717
Explain the process if acid from the stomach reaches the duodenum?
SI increases secretin release Causing the pancreas to release HCO3 HCO3 flow into SI Neutralises the SI acid
718
Explain the process if there is an increase in FA and aas related to pancreatic function?
Increased CCK release in SI Causing enzyme release from pancreas Increased flow of enzymes into SI Increased digestion of fast and protein in SI
719
Describe the structure of the liver?
Liver lobule Portal triad (hepatic portal veins, hepatic artery and bile canaliculus) Hepatocytes Hepatic sinusoids
720
What is included in the portal triad?
Hepatic portal veins Hepatic artery Bile canaliculus
721
Do the hepatic artery and hepatic protal vein mix?
Yes
722
What do the hepatocytes produce?
Bile
723
What other fucntions do hepatocytes have?
Nutrient storage Nutrient interconversion Detoxification
724
Describe the pathway for blood and nutrients through the liver system?
Hepatic portal vein and hepatic artery form the hepatic sinusoid Blood enters the central veins to the hepatic veins back to the heart The nutrients are taken out by the hepatocytes and stored or converted Hepatocytes also produce bile that pass into canaliculi to the hepatic ducts to aid in digestion
725
What nutrints are stored in the hepatocytes?
``` Glycogen Fat B12 A D E K Cu Fe ```
726
What is the function of the liver?
Bile production and secretion
727
Name the 6 components of bile?
``` Bile acids (secreted by L) Lecithin (secreted by L) Cholesterol (secreted by L) Bile pigments (secreted by L) Toxic metals (secreted by L) Bicarbonate (secreted by pancreas) ```
728
What is the function of bile acids, lecithin and cholesterol
Solubilse fat
729
What is the function of bile pigments?
Bilirubin from ahem
730
What is the function of toxic metals?
Detox in liver
731
What is the function of HCO2?
Neutralisation of acidic chyme
732
How do we improve the solubility of bile acids?
Conjugated with glycine or taurine forming bile salts
733
What is the function of the gallbladder?
Overflow area for bile from the common bile duct
734
How are bile salts recyled?
enterohepatic circulation
735
What is the pathway for bile?
``` Liver Bile duct Duodenum Ileum Hepatic portal vein Back to the liver 5% lost in the faeces ```
736
Explain the process of control of bile secretion?
Sphincter of Oddi controls the release of bile and pancreatic juice into the duodenum If contracted, stays closed and overflows into gallbladder If fat is present in the duodenum the response is to release CCK, in turn this relaxes the sphincter and contracts the gallbladder The bile enters the duodenum and solubilises the fat CCK activates pancreatic enzyme secretion and bile secretion
737
What is the other function of the gallbladder?
Concentrates the bile 5-20 times the normal of the liver Absorbs Na and H2O Via paracellular pathways
738
What is the cross-sectional structure of the SI?
``` Mucosa Submucosa Circular muscle Longitudinal muscle Serosa ```
739
What is present on the GI mucosa?
Plica: | - have villi increases SA
740
Describe the structure of the epithelium in the SI
``` Villi Crypts Lamina propria Goblet cells Endocrine cells Absorptive cells Muscularis mucosae ```
741
How often os the lining of the gut replaced?
Every 5 days
742
Describe the structure of an enterocyte?
Microvilli - higher SA | Cuboidal
743
Name 3 disaccharides of glycogen/starch?
Maltose Sucrose Lactose
744
Which enzymes catalyse maltose, sucrose and lactose to breakdown?
Maltase Sucrase Lactase
745
What is maltose broken down into?
2 glucose
746
What is sucrose broken down into?
1 glucose | 1 fructose
747
What is lactose broken down into?
1 glucose | 1 galactose
748
Which enzyme breaks down glycogen/starch?
Amylase
749
Which enzyme breaks down peptides?
Endopeptidases | Forming 2 smaller peptides
750
Which enzyme breaks down the smaller peptides?
Exopeptidases called aminopeptidase and carboxypeptidase to produce amino acids and even smaller peptides
751
How do the enterocytes transport nutrients across their membranes?
Na-coupled secondary active transport: - Na/K pump to bring in K - Na coupled with nutrient into cell - nutrients enter bloodstream - K leaves via K channel - also water follow Na
752
Explain the process of emulsification of fat in the stomach?
Mechanical breakdown in the antrum | Bile salts to stop the droplets from reforming large fat droplets in the duodenum
753
How are the droplets converted to micelles?
Pancreatic lipase | Into FA and monoglycerides
754
How are the FAs absorbed into the cells?
Diffuse into the cell
755
How do the enterocytes convert and package the FA for future use?
FA and monoglycerides travel to the ER Converted to triacylglycerol via triacylglycerol synthetic enzymes and packed via vesicles to form chylomicrons Chylomicron will travel in the lacteal via the lymphatic system to be absorbed into the blood
756
What is the defintion of segementation?
Processing the meal Small sections of the SI constrict and then relax to allow mixing Increasing Sa of the food to aid absorption
757
What os the defintion of peristalsis?
Contraction behind the bolus and relaxation ahead to move the bolus towards the anus
758
Name the parts of the LI?
``` Ileum Caecum Asceding colon ransverse colon Descedning colon Sigmoid colon Rectum ```
759
Describe the structure of the cross-sectional wall of the LI?
Intestinal crypts (very deep) (goblet cells) Submucosa Circular muscle Longitudinal muscle (tenia coli 3 lines)
760
Name the 2 sphincters in control of defaecation?
Anus closed by internal anal sphincter (SM under autonomic control) and external anal sphincter (skeletal muscle and voluntary control)
761
Explain the process of defaecation?
Wave of intense contraction (mass movement contraction) from colon to rectum Distension of rectal wall produced by MM of faeces into rectum activates the mechanoreceptors activating the defaecation reflex giving the urge to defaecate
762
Explain the process of the defaecation reflex?
Parasympathetic control via the pelvic splanchnic nerve: - contraction of rectum - relaxation of internal and contraction of external anal sphincter - Increased peristaltic activity in colin increases the PA on the external sphincter - relaxation of external sphincter under voluntary control allow expulsion of faeces

3rd Year BDS (21 decks)

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