Cardiovascular System Flashcards
Name the 3 causes of anaemia
Reduced production of Hb
Increased losses of Hb
Increased demand of Hb
Define anaemia
Reduction in haemoglobin in the blood
Define aplastic anaemia
Reduced normal RBCs as a result of bone marrow failure
What is thalassaemia?
Give the two types
Normal haem production
Genetic mutation of globin chains
- Alpha chains: Asians
- Beta chains: Mediterraneans
What are the 5 clinical effects thalassaemia?
Chronic anaemia Marrow hyperplasia (skeletal deformities) Splenomegaly Cirrhosis Gallstones
What 2 ways can you manage thalassaemia?
Blood transfusions
Prevent iron overload
What 2 reasons are there for an increased demand of Hb resulting in anaemia?
Pregnancy
Malignant disease
What ethnic group is sickle cell anaemia predominantly seen in?
Afro-caribbeans
Define sickle cell anaemia
Inherited Hb defect due to defect in structure of beta chain
Define HCT
Haematocrit: a measure of the total volume of RBC relative to the total volume of the whole blood in sample
Define microcytic anaemia and give its 2 causes
Small RBCs often hypochromic (pale) due to low Hb concentration
Caused by Fe deficiency and thalassaemia
Define macrocyclic anaemia and give its 2 causes
Large RBC; associated with maturation problems
Caused by vitamin B12/folate deficiency and retics
Define normacytic RBC and give its 3 causes
Normal RBCs
Caused by bleeding/renal/chronic disease
Define reticulocytes
Immature RBCs which are larger than RBCs
How can you detect anaemia using reticulocytes?
A reticulocyte percentage that is higher than normal is a sign of anaemia
What differences are there between reticulocytes and RBCs?
Reticulocytes are stained purple due to organelles/RNA
Reticulocytes are larger than RBCs
What are the 7 signs of anaemia?
Pale mucosa Smooth tongue (Fe deficiency) 'Beefy' tongue (Vit B12 deficiency) Pale Tachycardia (fast heart rate, due to lower O2 carrying capacity) Enlarged liver Enlarged spleen
What are 4 symptoms of anaemia?
Tired/weak
Dizzy
SOB (shortness of breath)
Palpitations
What 6 things can be investigated for anaemia?
Medical history
FBC (full blood count)
FOB (faecal occult blood)- blood in patients stool
Endoscopy/ colonoscopy
Renal function- patients with chronic renal disease will often become anaemic
Bone marrow examination
Name 3 ways anaemia can be treated
Replace haematinics (general term for nutrients required to make RBCs) e.g. Iron, folic acid, Vit b12
Blood transfusions
Erythropoietin- hormone; increases rate of RBC production
What 3 functions does blood have?
Transport of nutrients
Removal of waste
Transport of host defences
What are the 5 components of blood?
Cell component
Plasma proteins: albumin
globulin
Lipids
Nutrients
WaterDefine leukopenia
Low white cell count
Define thrombocytopenia
Low platelets
Define pancytopenia
All cells reduced
Define polycythaemia
Raised Hb
Define leukocytosis
Raised WCC
Define thrombocythaemia
Raised platelets
Define leukaemia
Neoplastic (abnormal) proliferation of white cells Usually disseminated (wide spread)
Define lymphoma
Neoplastic proliferation of white cells
Usually a solid tumour
In what 2 cases would someone receive a blood transfusion?
When one or more components of the blood has to be replaced quickly e.g. RBCs, platelets, clotting factors
When bone marrow cannot produce blood cells
What 3 complications can result from a blood transfusion and what can they cause?
- Incompatible blood
- Cell lysis: fever, jaundice, death - Fluid overload
- Heart failure - Transmission of infection
- Blood borne viruses e.g. Hep B, HIV
- Prion disease
- Bacterial infections e.g. Syphilis
Describe the transfusion protocol (3 steps)
Blood is filtered to remove any clots
The patients temperature, pulse and BP are monitored every 15 minutes during transfusion
Transfusion is stopped if there is any significant change
Define haemostasis
The arrest of bleeding
What 3 components can result in a haemostatic disorder?
Vascular component- retraction of vessel (collagen disorder)
Cellular component- platelets number and function
Coagulation component- adequate clotting
- adequate clot lysis
How would you investigate the platelet number and platelet function for haemostatic disorders?
Full blood count
‘Bleeding time’
How long does it take to make new platelets?
7-10 days
What are 3 visual signs of haemostatic disorders?
Purpura- skin rash from bleeding into skin from capillaries
Ecchymosis- bruise from release of blood into tissues either from injury or spontaneous leaking from vessels
Petechiae- small round flat dark red spots caused by bleeding into skin or beneath mucous membrane
What are the 3 types of inherited bleeding disorders?
Haemophilia A
Haemophilia B
Von Willebrands disease
What are 2 ways to develop an acquired bleeding disorder?
Warfarin
Liver disease
Define porphyria
How many does it affect
What are the 2 types
Abnormality of haem metabolism
1 in 10000 population affected
1. Hepatic porphyria
2. Erythropoietic porphyria
What are the clinical effects of porphyria?
Photosensitive rash
Neuropsychiatric disturbance in acute attacks (motor and sensory changes, seizures)
Hypertension
Tachycardia
Name 5 triggers of porphyria
Many drugs Pregnancy Acute infections Alcohol Fasting
What name is given to low Hb
Anaemia
What name is given to low WCC?
Leukopenia
What name is given to low platelet count?
Thrombocytopenia
What name is given to raised Hb?
Polycythaemia
What name is given to raised WCC?
Leukocytosis
What name is given to raised platelet count?
Thombocythaemia
What name is given when all cell types are reduced?
Pancytopenia
What 3 features of cancer cells cause them to be malignant?
Uncontrolled proliferation
Loss of apoptosis (cells don’t self destruct)
Loss of normal functions/products
Name 4 causes of leukaemia/lymphoma (aetiology)
Inherited DNA mutations (some associated with known syndromes)
Chemicals
Radiation
Viruses
What is a blast?
Immature cell
What group of cancers does leukaemia refer to?
Cancers of the bone marrow
What does leukaemia prevent and what 3 things does this result in?
Prevents normal manufacture of blood
Anaemia
Infections: neutropenia- decreased WBC so increased susceptibility to disease
Bleeding: thrombocytopenia- decreased platelets
What is the pathogenesis (disease process) of leukaemia?
- Clonal proliferation
- Replacement of bone marrow
- Increased marginalisation of productive normal marrow resulting in:
- marrow failure
- organ infiltration (leading to organ failure)
Name 5 things that can be a clinical presentation of leukaemia
Anaemia
Neutropenia- decreased WBCs
Thrombocytopenia- decreased platelets
Lymphadenopathy- neck lumps due to enlarged lymph nodes
Splenomegaly/ Hepatomegaly - swollen abdomen
Bone pain- especially in children
What 3 things can be clinical presentations of neutropenia?
- Infections associated with portals of entry e.g. Tonsillitis, pneumonia, thrush
- Reactivation of latent (dormant) infections
- Increased severity and frequency of infections, and can rapidly lead to systemic infections
Name 2 symptoms of neutropenia
Recurrent infections
Unusual severity of infection
Name 3 signs of neutropenia
Unusual patterns of infection and rapid spread
Will respond to treatment but recur
Signs of systemic involvement e.g. Fever, rigors (shivers), chills
What investigation can be done for neutropenia?
Unusual pathogens, usually bacterial
What are 5 symptoms of thrombocytopenia?
Bruise easily/spontaneously Minor cuts fail to clot Gingival bleeding Nose bleeds Menorrhagia- abnormally heavy menstrual bleeding
Name 4 signs of thrombocytopenia
Bruising
Petechiae- small dark bruises cause by bleeding into skin
Bleeding on probing
Bleeding/bruising following procedure
What is the peak age for acute lymphoblastic leukaemia?
4 y/o
What is the incidence of acute lymphoblastic leukaemia?
25 per 1,000,000 per year
What is the incidence of acute myeloid leukaemia?
25 cases per 1,000,000 per year
In what age group is acute myeloid leukaemia most prevalent?
The elderly
What is the most common form of leukaemia?
Chronic lymphocytic (lymphoid) leukaemia
What is lymphoma?
Clonal proliferation of lymphocytes arising in lymph node or associated tissue
What is the incidence of lymphoma?
200 cases per 1,000,000 per year
What is the ratio of number of suffers of non-hodgkins lymphoma to Hodgkin’s lymphoma?
6:1
Define Stage I of lymphoma tumour staging
Single lymph node region or single extra lymphatic site involved
Define Stage II of lymphoma tumour staging
Two or more sites on same side of diaphragm involved
Define Stage III of lymphoma tumour staging
Both sides of diaphragm involved
Define Stage IV of lymphoma staging
Diffuse involvement of extra lymphatic (and nodal disease)
What 3 tests may be used to help stage a tumour?
CT
PET
MRI
What 3 things does tumour staging take into account?
Number of nodes involved and site
Extra nodal involvement
Systemic symptoms
What is the peak age of Hodgkin lymphoma?
15-40 y/o
What is the clinical presentation of Hodgkin lymphoma?
Painless lymphadenopathy- enlargement of lymph nodes
Fever, night sweats, weight loss, itching
Infection
What are the 2 types of non-Hodgkin lymphoma and how are the divided?
B-cell: 85%
T-cell: 15%
What is the peak age to develop NHL?
Any age
What are 3 possible causes of NHL? (Aetiology)
- Microbial factors e.g. EBV
- Autoimmune disease e.g. Rheumatoid arthritis
- Immunosuppression e.g. AIDS, post transplant
Name 4 aspects of clinical presentation of NHL compared to HL
- Lymphadenopathy- enlarged lymph nodes (often widely disseminated)
- Extra-nodal disease more common- e.g. Oropharyngeal involvement (noisy breathing and sore throat)
- Symptoms of marrow failure e.g. Aplastic anaemia
- Constitutional symptoms less common e.g. Fever, weight loss
Define Multiple Myeloma
The malignant proliferation of plasma cells (WBCs) in bone marrow
What are 3 clinical features of Multiple Myelomas?
- Monoclonal paraprotein released by malignant plasma cells found in the blood and urine
- Lytic bone lesions (destruction of bone cells)- pain and fracture likely
- Excess plasma cells in bone marrow- leading to marrow failure
Name 5 treatment for haematological malignancies
Chemotherapy Radiotherapy Monoclonal antibodies Haemopoietic stem cell transplantation Supportive therapy e.g. Pain control, nutrition, psychological support
What does chemotherapy target?
Targets cells with high turnover rate (e.g. Mucosa) to induce cell death
What is a disadvantage of chemotherapy targeting?
Results in many unwanted effects in normal high turn over tissues
What are 3 side effects of chemotherapy?
Hair loss
Nausea and vomiting
Tiredness
What is a long term risk of chemotherapy?
Risk of oncogenesis (development of new abnormal growth) in surviving patients
Name 3 examples of chemo drugs
Methotrexate
Cyclophosphamide
Vincristine
Define radiotherapy
Cytotoxic effect of ionising radiation
Describe the treatment of monoclonal antibodies
Monoclonal antibodies specific to cancer cell antigens are produced artificially in large quantities and given to patient
What is a disadvantage of monoclonal antibodies and how are the drugs recognised?
Very expensive to produce and deliver
Drug names end in “-mab”
Define allogeneic stem cell transplant
Stem cell from live donor, either relative or stranger who has been matched
Define autologous stem cell transplant
Stem cells from patient themselves
Name 6 oral manifestations of haematological malignancies
Gingival swelling Mucosal pallor Spontaneous bleeding Petechiae Oral ulceration Infection
What importance does the mouth have in patients receiving cancer therapy?
The mouth is a potential source of infection which can be life threatening in an immunocompromised patient
Pre-cancer treatment, what preventative measures would a dentist take with the patient?
OHI
Dietary advice
If gingival disease- alcohol free chlorohexidine
Applicator trays for fluoride gel and tooth mousse
High fluoride toothpaste
High fluoride varnish application
Define mucositis
Acute inflammation of the mucosa
What preventative management can be done to for patients with mucositis?
Improve OH of patient so decreased healing time
Ill fitting dentures/sharp restorations adjusted
Mucosal shields (if radiotherapy)
Name 6 ways mucositis can be managed
- Difflam spray
- 2% lidocaine mouthwash prior to eating
- Gelclair
- Chlorohexidine
- Ice chips- oral cooking
- Cell transplant
Define xerostomia
Thick, acidic and viscous saliva with loss of protective functions
What 2 approaches are there to treat xerostomia?
Saliva stimulation
Saliva replacement
Name 4 ways to for stimulate saliva
Chewing sugar free gum
Pilocarpine
Acupuncture
Acid pastilles (contraindicated in dentate)
Name 4 ways to replace saliva
Taking sips of water
Saliva orthana
Biotene
Bio Astra
What 4 things should patients with xerostomia avoid?
Hard, spicy, strong flavoured foods
Foaming toothpaste
Alcohol and smoking tobacco
Fizzy drinks and fruit drinks
Name 3 irreversible risk factors of CV disease
Age
Sex
Family history
Name 4 reversible behavioural risk factors for CV disease
Smoking
Obesity
Diet
Exercise
Name 4 reversible medical risk factors for CV disease
Hypertension
Hyperlipidaemia (high cholesterol)
Diabetes
Stress
Name 8 risk factors for hypertension
Age Race Obesity Alcohol Family history Pregnancy Stress Drugs e.g. non-steroidal, oral contraceptive
Name 6 ways you would test if someone is at high risk of CV disease
Family history Diet Smoking Test cholesterol Test blood pressure Test for type 2 diabetes
Name 4 ways someone can present with CV disease
Angina
Myocardial infarction
Stroke
Claudication
Name 4 approaches to preventing/controlling CV disease
- Lifestyle changes
- Control total cholesterol- statin treatment
- reduce cholesterol to
Name 2 ways drugs are used in CV system and give examples for each
- Prevent FURTHER disease
- anti platelet drugs
- lipid lowering drugs
- anti-arrhythmics - To reduce symptoms of current current disease
- diuretics
- anti-arrhythmics
- nitrates
- calcium channel blockers
- ACE inhibitors
Give three examples of anti-platelet drugs
Aspirin
Clopidrogel
Dipyridamole
How does aspirin work?
It inhibits platelet aggregation
By altering balance between Throboxane A2 and Prostacyclin
It is irreversible for the life of the platelet
How does Clopidrogel work?
It inhibits ADP induced platelet aggregation
How does Dipyridamole work?
It inhibits platelet phosphodiesterase (enzyme which breaks phosphodiester bonds)
How do Lipid-Lowering drugs work?
They inhibit cholesterol synthesis in liver
Therefore reducing both the total cholesterol and LDL cholesterol
What side effect can lipid lowering drugs have?
Possible myositis (muscle disease) with some drug interactions
Give an example of an anti-arrhythmics and 2 types of it
Beta-adrenergic blockers (beta blockers)
Atenolol- selective: B1 only
Propranolol- non-selective: B1 and B2
What 3 effects so beta blockers have?
- Prevent increase in HR
- cause postural hypotension
- prevent unusual heart rhythms which can lead to a MI - Reduce heart efficiency
- make heart failure once - Block beta receptors in lungs
- make asthma worse/difficult to treat
How do diuretics work?
They increase salt and water loss therefore decreasing plasma volume and decreasing cardiac workload
What is a side effect of diuretics?
Can lead to Na+/K+ imbalance if not monitored
Name 2 types of nitrates
Glyceryl trinitrate (GTN)- short acting Isosorbide Mononitrate- long acting
What 3 ways do nitrates work?
- Dilate veins- reduce preload to heart
- Dilate resistance arteries- reduce cardiac workload (afterload)
- reduce cardiac oxygen consumption - Dilate collateral coronary artery supply- reduce anginal pain
What 3 ways can nitrates be administered and why?
Sublingual
Transdermal
Intravenous
Inactivated by first pass metabolism
What side effect do nitrates have?
Headache
What 2 ways do calcium channel blockers work?
They block calcium channels in smooth muscle
Some are more active in heart muscle
- reduces strength of heart contractions
- e.g. Verapamil
Some are more active on peripheral blood vessels
- relaxation and vasodilation
- e.g. Nifedipine, amlodipine
Name a side effect of calcium channel blockers
Some cause gingival hyperplasia (increased number of cells)
- those acting on peripheral blood vessels
How do Angiotensin Converting Enzyme (ACE) inhibitors work and give examples?
Inhibit conversion of Angiotensin I to Angiotensin II
Prevents aldosterone dependant reabsorption of salt and water
Therefore decreases BP
E.g. Enalapril, ramapril, lisinopril
Name 2 side effects of ACE inhibitors
Cough
Hypotension
What other drugs have the same effect as ACE inhibitors?
Angiotensin II blockers (e.g. Losartan)
Inhibit same system but use different mechanism
Define thrombosis
The formation of a solid or semi-solid mass from the constituents of the blood within the vascular system during life
Name 3 factors predisposing to thrombosis
- Abnormality of blood vessel wall particularly the endothelium (e.g. Atheroma)
- Alterations in blood flow- stasis and/or turbulence
- Hypercoagulable blood
Name 4 ways blood vessels are damaged
Atheroma
Inflammation
Trauma
Bacterial toxins
Name 5 occurrences that blood is hypercoagulable
Following surgery In disseminated cancer During pregnancy While taking oral contraceptive pill In genetic deficiency states of blood clotting factors
Name 4 locations of thrombi
Arterial
Venous
Cardiac
Capillaries
Name 4 causes of DVTs
Bed ridden following surgery
Heart failure
Severe tissue injury
Pelvic tumours
Name the 3 fates of thrombi
- Removal by fibrinolytic system
- Organisation- replacement fibrosis
- Embolism
Define embolism
Movement of solid, liquid or gaseous material through the blood and its impaction in a blood vessel at a site distant from its origin
What are the 2 main types of embolism and explain their mechanism
Systemic thrombo-embolism
- thrombi form on left side of heart or in arteries, break free and Impact distally in systemic arterial tree causing ischaemia or infarction due to obstruction of blood flow
Pulmonary Thrombo-embolism
- thrombi arise in deep veins of leg or pelvis
- if large, emboli obstruct main pulmonary arteries arising from right side of heart (sudden death)
- if smaller, emboli obstruct smaller, more peripheral pulmonary artery branch (clinically silent)
Define atherosclerosis
Patches (plaques) of thickening of artery lining
Due mainly to accumulation of plasma lipids, proliferation of smooth muscle and formation of fibrous tissue
Site of occurrence of atherosclerosis
Any ARTERY
Name 4 clinical effects of atherosclerosis
- Arterial narrowing sufficient to cause ischaemia
- Predisposes to throbosis because of lumenal occlusion of artery
- Embolism
- Weakening of artery wall leading to aneurysm formation (swelling in wall of artery)
Name 6 major risk factors of atherosclerosis (aetiology)
- Age- atheroma progresses slowly throughout adult life
- Sex- lower incidence in women until menopause
- Plasma lipids- hyperlipidaemia predisposes to atheroma
- Hypertension- atheroma risk increases with increasing BP
- Cigarette smoking
- Diabetes mellitus
Define ischaemia
Deficient supply of blood to an area such that it becomes hypoxic (deficient 02 to tissues)
What is the aetiology of ischaemia?
Most commonly due to narrowing or obstruction of arterial supply caused by atheroma, thrombosis or embolism
Name the 2 types of ischaemia and their clinical effects
- Partial ischaemia (blood flow reduced to a level that is adequate while resting, but hypoxia develops at times of increased oxygen demand e.g. Exercise)
a) Angina pectoris- myocardial ischaemia due to narrowed, atheromatous coronary arteries- often induced by exercise and causes sever crushing central chest pain
b) Intermittent claudication- atheromatous narrowing of leg arteries leading to pain in calf muscles induced by exercise
- Complete ischaemia- no blood flow leading to tissue infarction (organs supplied by blocked artery dies)
Define infarction and give its aetiology
Tissue death or necrosis due to reduction or loss of blood supply.
Usually due to arterial narrowing or occlusion which is often atheromatous and/or thrombotic in nature
What 2 things is tissue susceptibility to infarction dependant on?
- Metabolic rate of tissue- brain more susceptible than fibrous tissue
- Anatomy of vascular supply e.g. Occlusion of an end artery in brain- infarction
What is the fate of infarcts?
Dead tissue incites an inflammatory reaction followed by granulation tissue and eventually fibrous scar replacement
Define ischaemic heart disease and give its aetiology
An imbalance between myocardial oxygen supply and demand
Most commonly due to narrowed atheromatous coronary arteries and/or thrombosis
Name 3 clinical effects IHD
Angina pectoris- myocardial ischaemia due to narrowed coronary arteries
Sudden cardiac death
Myocardial infarction
Name 3 complications of MIs
Cardiac arrhythmias
Cardiac failure/ cardiogenic shock
Mural thrombosis and/or thromboembolism
Define hypertension
Raised systemic arterial pressure with systolic >140mmHg, diastolic >90mmHg
What are the two classifications of hypertension?
Primary (essential, idiopathic)- no detectable underlying cause
Secondary- resulting from renal diseases or adrenal diseases (e.g. Cushing’s)
Name 3 pathological effects of hypertension
- Risk factor for development of atheroma, cardiac failure, renal failure and cerebral haemorrhage
- In heart, can lead to left ventricular hypertrophy
- In brain, associated with rupture of micro aneurysms
What is the aetiology of both types of hypertension?
Primary- inherited defect of sodium handling by cell membranes (e.g. In the kidney)
Secondary- the renin/angiotensin/aldosterone system is often involved
Define cardiac failure
Cardiac failure occurs when cardiac function (pump) fails to maintain a circulation adequate for metabolic needs of body DESPITE adequate blood volume
Name 3 causes of cardiac failure
- Myocardial injury e.g MI
- Increased workload e.g hypertension, valvular heart disease
- Abnormal cardiac rhythm
Name the 3 manifestations of cardiac failure
Left ventricular failure
Right ventricular failure
Biventricular (congestive) cardiac failure
Define shock
Widespread hypofusion (low flow) of tissues due to inadequate effective circulating blood volume
As a result there is systemic cellular hypoxia, increased anaerobic metabolism and progressive derangement of cellular function
Name and explain the 3 types of shock
- Hypovolaemic shock
May be due to: haemorrhage or fluid loss
Overall effect: critical reduction in blood/plasma volume (not enough blood) - Cardiogenic shock
May be due to: MI, cardiac rupture, massive pulmonary thromboembolism
Overall effect: failure of myocardial pump due to damage or blood flow obstruction (adequate blood volume, but inadequate circulation) - Septic shock
Due to: bacterial infection
Overall effect: loss of vascular tone, pooling of blood in peripheral vessels (normal blood volume, abnormal blood distribution)
Name and describe the 3 pathological stages of shock
- Compensated shock- mildly decreased BP, increased HR, peripheral vasoconstriction so skin cold and clammy
- Decompensated shock- if circulatory deficiency persists compensatory mechanisms fail so further decrease in BP, increase in HR, systemic tissue hypoxia and worsening tissue damage
- Irreversible shock- if circulatory defects not corrected, cell necrosis occurs in vital organs leading to coma and death
Define valve stenosis
Decrease in size of valve orifice so increased pressure load in preceding cardiac chamber
Define valve incompetence
Failure of complete valve closure, causes regurgitation of blood so increased volume load for cardiac chambers on both sides of valve
Define infective endocarditis (IE)
Colonisation of normal or damaged heart valves by microorganisms with the formation of friable, infected thrombi (vegetations) on the surface of the valve cusps and resultant valve injury
Name 3 predisposing factors to infective endocarditis
- Conditions which cause bacteraemia or septicaemia e.g. Dental procedures
- Abnormalities of heart valves whether congenital or acquired
- Immunosuppressed host
Name 3 clinical effects of bacterial endocarditis
- Injury to valves (incompetence and/or stenosis) or adjacent myocardium (abscess formation, perforation)
- Embolic events
- Fever, malaise, weight loss
Name the 2 main types of angina
‘Classical’ angina
‘Unstable’ angina
Name 4 symptoms of ‘classical’ angina
No pain at rest
Pain with certain level of exertion
Pain relieved by rest
Gradual deterioration
Name signs of ‘classical’ angina
Often none
Name 5 investigations of angina
ECG- resting and exercise Eliminate other diseases e.g. Thyroid, anaemia, valve Angiography Echocardiography Isotope studies
Name the 2 main treatments of angina and ways they are done (2 each)
- Reduce oxygen demands of heart
- reduce afterload (blood pressure)
- reduce preload (venous pressure) - Increase oxygen delivery to tissues
- dilate blocked/ narrowed vessels (angioplasty)
- bypass blocked/narrowed vessels (CABG)
Name 2 non-drug therapies for angina
- Live with limitations
2. Modify risk factors- stop smoking, graded exercise programme, improve diet/ control cholesterol
Name 4 situations drug therapy is used to treat angina and give examples of the drugs used
- To reduce MI risk– aspirin
- To treat hypertension- diuretics, Ca channel antagonists
- ACE inhibitors, Beta blockers - To reduce preload/dilate coronary vessels- nitrates
- In emergency treatments- GTN spray/tab
Where is peripheral vascular disease usually located and what causes it?
Usually lower limb
Atheroma in femoral vessels
Name 5 characteristics of peripheral vascular disease
- Claudication pain in limb on exercise (cramping)
- Limitation of function
- Poor wound healing
- May lead to tissue necrosis or gangrene
- Aggravated by CV risk factors
What are the 2 main strategies for infarction and how are these done?
- Reduce tissue loss from necrosis
- open blood flow to ischaemic tissues (thrombolysis, angioplasty)
- bypass obstruction (CABG, femoral bypass) - Prevent further episode
- risk factor management
- aspirin
Name 3 causes of a brain infarction (stroke)
Usually embolism from atheroma
Occasionally cerebral bleed
Rarely vessel thrombosis (good collateral blood supply)
Name a stroke that has symptoms lasting less than 24 hours
Transient ischaemic attacks (TIAs)
What are the symptoms and signs of MIs?
Central chest pain, nausea, pale, sweaty
Name 2 MI investigations
- ECG- ST segment elevating/ T wave abnormalities
- Cardiac enzymes- troponin
- creatinine kinase
- LDH and AST
What is the primary care of MIs?
Aim to get to hospital
Analgesia (pain killer), aspirin, reassurance
BLS if required (cardiac arrest)
What hospital care is given to MIs?
Thrombolysis if indicated, or acute angioplasty and stenting
Drug treatment to reduce tissue damage
Prevent reoccurence/complications
Name 2 drugs that can be used for thrombolysis
Streptokinase
TPA
Name 6 contraindications of thrombolysis
Injury Surgery Severe hypertension Diabetic eye disease Liver disease Pregnancy
Name 6 complications of MIs
- Death
- Arrhythmias
- Heart failure
- Ventricular hypofunction and thrombosis
- damaged ventricular wall, clots could form on wall due to lack of
movement
- damaged ventricular wall, clots could form on wall due to lack of
- DVT and pulmonary embolism
- Complication of thrombolysis
Define bacteraemia
It is the transient (short lived) presence of bacteria in the bloodstream
Define septicaemia
It is the persistent presence of bacteria in the blood stream, with attendant signs and symptoms
Define sepsis
“The host response to infection”
What 4 things make up the SIRS criteria?
Chills and fevers
High HR
Panting, increased CO2 in blood
High/low WCC
What criteria equals sepsis
Infection
+
SIRS criteria (at least 2)
What criteria equals severe sepsis?
Give its mortality rate
Sepsis
+
Organ dysfunction
40% mortality
What criteria equals septic shock?
Give its mortality rate
Sepsis
+
Shock refractory to fluid resuscitation
60% mortality
Name 4 reactions of sepsis
Endothelial damage
Micro vascular dysfunction
Impaired tissue oxygenation
Organ injury
What results in clinical features of gram negative septicaemia?
Result from endotoxin release (poison within bacteria)
What 4 events make people most susceptible to gram negative septicaemia?
Major GI surgery
Immunosuppressive chemotherapy
Burns
Extremes of age
Where are most gram negative septicaemias acquired?
Hospital acquired
What is the most common isolate of gram negative septicaemia?
E. Coli
What causes clinical features in gram positive septicaemia?
Teichoic acid and peptidoglycan from cell wall of bacteria
Name 4 sources of infection of gram positive septicaemia
- Skin e.g. Indwelling catheters
- Respiratory tract e.g. S. Pneumoniae
- Bone/joint infections e.g. S. Aureus
- Oral cavity
Who is susceptible to fungal septicaemia and what is its most common isolate?
Immunosuppressed hosts e.g. Haematological malignancy, AIDS
Candida albicans
How is septicaemia treated?
IV fluids, oxygen and other supportive measures
‘Blind’, empirical IV antibiotics- broad spectrum given as soon as infection suspected
Identify and remove source where possible e.g. Foreign body, catheter
Define infective endocarditis
Microbial infection of endothelial lining of heart
Usually manifests are vegetations on heart valves
What 6 types of patients are ‘at risk’ of infective endocarditis?
- Acquired valvular heart disease
- Prosthetic heart valve
- Structural congenital heart disease (abnormalities of heart tissue)
- Previous endocarditis
- Hypertrophic cardiomyopathy (enlarged heart)
- Recurrent bacteraemia
Name 3 clinical feature of IE
Fever
Heart murmur
Splenomegaly
Name 2 common microbial culprits of IE
Streptococci – oral streptococci
Staphylococci– staphylococcus aureus
Where is the primary habitat of oral streptococci?
Oral cavity/ upper respiratory tract
Name 4 ways IE is diagnosed
- Clinical signs
- Blood cultures (3 sets over 24hrs)
- Echocardiography- visualise lesions
- DUKE criteria
Name 2 outcomes of hypertension and what they can lead to
- Accelerated atherosclerosis
- MI
- Stroke
- Peripheral vascular disease - Renal failure
What are common causes of hypertension?
There are none
Name 2 rare causes of hypertension
- Renal artery stenosis (narrowing)
- Endocrine tumours
- phaechromocytoma
- Cushing’s syndrome
What are signs of symptoms of hypertension?
Usually none
May get headache
May get TIAs
Name 5 ways hypertension can be investigated
- Urinalysis- look at what kidneys are excreting in urine
- Serum biochemistry
- Serum lipids
- ECG
- Renal ultrasound, renal angiography, hormone estimations
What is the aim of treating hypertension
To get BP to less than 140/90mmHg
Name 2 ways hypertension can be treated
- Modify risk factors- smoking, exercise, weight
2. Single daily drug dose
Define heart failure
“output of heart incapable of meeting demands of tissues”
Give examples of both high and low output cardiac failure
High output failure- anaemia, thyrotoxicosis
Low output failure- cardiac defect e.g. MI, valve disease
What is the biggest cause of heart failure?
Ischaemic heart disease
Name 5 things that can cause low output heart failure (aetiology)
- Heart muscle disease e.g. MI
- Pressure overload e.g. Hypertension, aortic stenosis
- Volume overload e.g. Mitral/aortic incompetence
- Arrhythmias e.g. Atrial fibrillation, heart block
- Drugs e.g. Beta blockers, corticosteroids
Name 8 symptoms of heart failure
SOB Ankle swelling Chronic lack of energy Difficulty sleeping due to breathing Swollen/tender abdomen Cough with frothy sputum Increased urination at night Confusion and/or impaired memory
Name signs of left heart failure
LUNGS and systolic effects
- dyspnoea (difficulty breathing), tachycardia, low BP, low volume pulse
Name signs of right heart failure
Venous pressure elevated
- swollen ankles, ascites (accumulation of fluid- abdominal swelling), raised JVP (jugular venous pressure), tender enlarged liver, poor GI absorption
What treatment would be given for acute heart failure
Emergency hospital management
- O2, morphine, frusemide (diuretic used to treat fluid retention)
What treatment would be given for chronic heart failure?
Community based
- improve myocardial function
- decrease ‘compensation’ effects (decrease salt and water retention)
- where possible, treat cause
What 4 types of drugs may be used in chronic heart failure and why
- Diuretics- increase salt and water loss
- ACE inhibitors- decrease salt and water retention
- Nitrates- decrease venous filling pressure
- Inotropes e.g. Digoxin
What drugs would be stopped when treating heart failure and why
Stop negative inotropes e.g. Beta blockers
- decrease HR and makes heart beat less efficiently
Name the 4 heart valves and state what side they are on
Left- aortic, mitral (bicuspid)
Right- pulmonary, tricuspid
The heart valves on what side of the heart most commonly fail and why?
Left side
Valves have to do more work under higher pressure
What 4 things cause valve disease?
- Congenital abnormality e.g bicuspid aortic valve (instead of tricuspid)
- MI
- Rheumatic fever
- MAY cause valve damage
- Patients with history MUST be investigated for RHD
- If no disease, no antibiotic prophylaxis is required - Dilation of aortic root
What 2 types of replacement valves are there?
Mechanical Porcine (pig valve)
Give 3 facts about porcine valves
Only last 10 years
Do not need anticoagulant
Good for elderly and young
Name 4 congenital heart defects and describe them
- Atrial septal defects- hole in wall between the 2 atria
- Ventricular septal defects- hole in wall between 2 ventricles
- Patent ductus arteriosus- opening between 2 major blood vessels leading from heart (usually closes after birth)
- Great vessel malformations
What is cyanosis, give the 2 types and when it occurs
Bluish discolouration of skin and mucous membranes resulting from inadequate amounts of O2 in blood
Central- from congenital heart disease
Peripheral- cold environment
Exists when there is 5g/dL or more if DEoxygenated Hb in blood
What is the term for a fast heart rate/rhythm and give 2 examples
Tachy arrhythmias
- atrial fibrillation
- ventricular tachycardia– diastolic time decreases so chambers less filled
What is the term for slow heart rates/rhythms and give 2 examples
Brady arrhythmias
- heart block (electrical impulses impaired)
- drug induced– beta blockers, digoxin
What are pace makers used to treat and how do they work?
Treat bradyarrhythmias
Senses electrical impulses in heart and stimulates heart beat if one does not occur
What is the term for a normal heart rhythm and explain the wave
Sinus rhythm
P-wave: atrial depolarisation
QRS complex: ventricular depolarisation
T-wave: ventricular repolarisation
Q wave most seen in patients who’ve suffered MIs
What is the term for a heart no longer beating and why is this the case?
Asystole
No electrical activity (defibrillator won’t help)
Define ventricular fibrillation
Unstable electrical activity (usually during MI)
No cardiac output
Treat with defibrillation
Name 5 dental treatments that would require no special care for those with coagulation problems
Hygiene therapy RPDs Restorative (including crowns and bridges) Endodontics Orthodontics
Name 4 dental treatments that would require special care for those with coagulation problems
Extractions
Minor oral surgery
Periodontal surgery
Biopsies
What 5 things need to be considered/done when performing extractions/surgery on patient with coagulation problems
- Appropriate monitoring prior to treatment
- Atraumatic treatment
- Consider antibiotics
- Observe to ensure haemostasis (arrest in bleeding)
- Comprehensive post-op instructions
What are the 2 main types of antithrombotic medication
Oral anti coagulation
Antiplatelet medications
What are 5 indications for the use of oral anticoagulants?
Atrial fibrillation DVT Heart valve disease Mechanical heart valves Thrombophilia
Name the 4 main types of oral anticoagulants available and an example of each
- Coumarins e.g. Warfarin
- Indanediones e.g. Phenindione
- Direct thrombin (DT) inhibitor e.g. Dabigatian
- Factor Xa inhibitor e.g. Apixaban
What is the daily dose of warfarin?
1-15mg
How is warfarin response measured?
INR (international normalised ratio)
What is INR?
Ratio of the patients prothrombin time (PT) to a standardised ‘normal’ PT
INR= patient PT/mean normal PT
What is the target INR for
- Mechanical heart valves
- Recurrent VTE while adequately anti coagulable
- Other cases
- 3.0-4.0
- 3.0-4.0
- 2.0-3.0
Name 4 medications that should be avoided by people with coagulation problems (on warfarin)
Aspirin (as an analgesic)
Co-proxamol
Ketorolac
Azole anti-fungal drugs
What is major risk for warfarin users
Haemorrhage
Name 4 characteristics of DT and FXa inhibitors
No routine blood tests required
Standard dose for each patient
Tablets take either once or twice a day
No reversal agent available
Name 5 anti-platelet medications
Low dose aspirin Clopidogrel Dipyridamole Tirofaban Ticagrelor
What 3 effects do antiplatelet drugs have on clotting
Inhibit platelet aggregation
Inhibit thrombosis formation
Define inherited bleeding disorders
A genetic defect which effects the coagulation of blood
Name 3 things inherited bleeding disorders may affect
- Coagulation cascade
- a reduction in one or more of the coagulation factors - Platelets
- number
- function - A combined deficieny
Name 4 common inherited bleeding disorders and give the different subtypes for each (where applicable)
- Factor VIII deficiency
- haemophilia
- haemophilia A - Factor IX deficiency
- Christmas disease
- Haemophila B - Von Willebrands disease (reduced factor VIII level)
- Factor XI deficiency
Describe the inheritance of factor VIII and IX deficiencies
Sex-linked recessive
Males are affected
Females are carriers
How are severe and moderate cases of factor VIII deficiency treated
Require use of recombinant factor VIII
How are mild sufferers and carriers of factor VIII deficiency treated?
Majority respond to DDAVP
Very mild cases may only require oral tranexamic acid
How are sufferers of Factor IX deficiency treated?
Require recombinant factor IX
Does not respond to DDAVP
Describe the inheritance of Von Willebrands disease
Autosomal dominant
Sexes affected equally
How is Von Willebrands disease treated
Majority respond to DDAVP
Very mild cases may only need oral tranexamic acid
Name 3 ‘safe’ LA injection sites for patients with bleeding disorders
Buccal infiltration
Intraligamentary injections
Intrapapillary injections
Name 3 ‘dangerous’ sites for LA injections
Inferior alveolar nerve block
Lingual infiltration
Posterior superior nerve block
Name 5 steps taken when performing extractions/surgery on patient with bleeding disorder
- Appropriate care from haemophilia unit
- Atraumatic treatment
- Consider antibiotics
- Observe after surgery
- 2-3 hours for mild/carriers
- overnight for severe/moderate - Comprehensive post-op instructions
Define thrombophilia
Increased risk of developing blood clots
Name 4 types of inherited thrombophilia syndromes
Protein C deficiency
Protein S deficiency
Factor V Leiden
Antithrombin III deficiency
Name 6 ways to acquire thrombophilia
Antiphospholipid syndrome Oral contraceptives Surgery Trauma Cancer Pregnancy
What is the term for decreased platelet numbers
Thrombocytopenia
What is the term for normal platelet numbers but abnormal function
Qualitative disorders
What is the term for increased platelet numbers
Thrombocythemia
At what platelet count can dental treatment be safely done in thrombocytopenia patients
Platelet count >50*10x9
Name 3 common causes of liver disease
Alcohol
Hepatitis
Drug induced
What haematological changes occur in those with liver disease in terms of:
- Hb
- Platelets
- PT (prothrombin time)
- APTT (activated partial thromboplastin time)
- Thrombin time
- Little change
- Decrease
- Increase
- Increase
- Increase
