CMS Flashcards
anaemia
reduced haemoglobin level
signs & symptoms of anaemia
symptoms - tiredness, weakness, dizziness, SoB, angina
signs - paleness, ankle swelling, tachycardia
3 types of anaemia
- microcytic
- macrocytic
- normocytic
microcytic anaemia (2)
caused by:
- Fe deficiency; 3 main causes = menstruation, GI bleed, poor intake; ferratin tested, angular cheilitis, spooned nails & smooth tongue may be seen clinically
- thalassemia; normal haem but globin chain production is modified, 2 types = alpha in Asian & beta in Mediterranean, clinically = chronic anaemia, bone marrow hyperplasia, cirrhosis, gall stones, can only be managed by blood transfusion
macrocytic anaemia (3)
caused by:
- vit B12 deficiency ;occurs in pernicious anaemia where autoimmune reaction against parietal cells which should release intrinsic factor which aids absorption of B12 in terminal ileum, can also occur in Chron’s
tx = supplementation via injection
clinically = beefy tongue, dysaesthesia, recurrent oral ulceration, mucosal atrophy
- folic acid deficiency; e.g. in pregnancy / chron’s (absorbed in jejenum)
- reticulocytes; increased bleeding leads to anaemia itself so immature blood cells added to blood & are larger as they still contain organelles so make blood macrocytic
normocytic anaemia (3)
RBCs of normal size but too few, caused by:
- renal disease; glomerulonephritis (glomerulus doesn’t filter properly & blood lost in urine) or renal failure (no endocrine function of kidneys so erythropoietin no produced so kidneys not stimulated to make RBCs)
- sickle cell anaemia; rbcs change shape under certain concentrations of oxygen so they cannot pass through capillaries
- excessive bleeding
to diagnose cause of anaemia (4)
MCV - normal = 75-90Fl/red cell
haemoglobin - normal = <50m 14-18gm/DL, <50f 12-16gm/DL, >50m 12.4-14.9gm/DL, >50f 11.7-13.8gm/DL
RBC count - normal = M 4-5.9x10to12/L, F 3.8-5.2x10 to 12/L
haematocrit - normal = m 41-50%, f 36-44%
GA & anaemia
under GA general oxygen capacity will be lower so dangerous for those with anaemia especially sickle cell
haematological malignancies
haematological cell line can turn neoplastic but earlier in the line the more aggressive the malignancy
cause unknown
leukaemia
cancer of bone marrow which prevents normal blood manufacture leading to
- anaemia; due to insufficient blood production
- infection; neutropenia
- increased bleeding; thrombocytopenia
neutropenia
lack of neutrophils in the blood so disease related to portals of entry
ptx can present with oral candidosis / tonsillitis
thrombocytopenia
decrease in platelet count causing increased bleeding time & increased frequency of bruising
signs & symptoms of leukaemia (6)
anaemia
neutropenia
thrombocytopenia
bone pain
lymphadenopathy
spleno/hepatomegaly (increased size)
acute lymphoblastic anaemia
body in catabolic state so loss of body weight, high heart rate so fever, sweat, malaise , lymphadenopathy & tissue infiltration
prognosis in young is better
acute myeloid leukaemia
affects non lymphocytes
presentation = same as acute lymphoblastic
chronic lymphocytic leukaemia
mostly affects elderly
B cell lymphoproliferative disease i.e. causes out of control B cell growth
slow progression & asymptomatic
only detected on routine blood tests
chronic myeloid leukaemia
least common
generally hereditary
increase in neutrophils & their precursors
lymphoma
clonal proliferation of lymphocytes in a lymph node or associated lymphoid tissue
solid tumour but some cells may leak into blood
2 types = hodgkin’s & non hodgkin’s
non hodgkin’s more common & more aggressive
hodgkin’s lymphoma
painless lymphadenopathy which will fluctuate in size, often cervical & pain on drinking alcohol
fever, night sweats, weight loss, itching, increase in unusual infections
high cure rate
non hodgkins lymphoma
generally affects B lymphocytes
caused by microbial disease / autoimmune disease / immunosuppression
prognosis not great and 50% relapse
lymphadenopathy widely disseminated & extra nodal disease more common, if waldeyer’s ring affected sore throat & noisy breathing, symptoms of bone marrow failure i.e. fatigue, anaemia, neutropenia & thrombocytopenia
multiple myeloma
malignant proliferation of plasma cells causing increased protein in blood & urine, lytic bone lesions leading to fracture & excess plasma cells in bone marrow leading to bone marrow failure
main symptoms = increased infection, bone pain, renal failure (glomerulus clogged with protein) & amyloidosis
tx of haematological malignancies
chemo/radiotherapy, monoclonal antibodies, haemopoietic stem cell treatment & supportive therapy
what is needed & where is production of clotting factors 2, 7, 9, 10
produced in liver & required vitamin K
fibrinolysis factors
antithrombin III will affect intrinsic pathway by inactivating coagulation factors in pathway, protein S will be a cofactor for protein C and they both have anticoagulant effects as they inactivate factor V & VIII
liver will produce all these factors & vitamin K important for proteins C & S
if patient in shock i.e. lost excessive amounts of blood
immediate - stop bleeding via vascular, platelet & plasma responses i.e. smooth muscle constriction & platelet adhesion & aggregation by endothelium
short term - BP restored by vasoconstriction produced by thromboxane A2 & ADP
medium term - restore volume of fluid by activating RA system so kidney absorbs more water & salt to keep blood volume up, ADH has similar effect as well as vasopressin effects constricting blood vessels
long term - replace constituents of blood
2 types of haemophilia
haemophilia A - factor VIII deficiency
haemophilia B - factor IX deficiency
haemophilia A
sex linked recessive
factor VIII deficiency
carriers/mild = DDAVP used to increase levels of factor VIII / oral tranexamic acid (antifibrinolytic agent)
moderate / severe recombinant = factor VIII should be used to replace factor lost
haemophilia B
sex linked recessive
factor IX deficiency
carriers/mild = oral tranexamic acid as DDAVP will not increase factor IX levels
moderate / severe = only use of recombinant factor IX
von willebrands disease
reduced factor VIII levels & reduced platelet aggregation
autosomal dominant disease characterised by deficiency of von willebrands factor
tx = DDAVP to increase factor VIII or oral tranexamic acid
dental relevance of bleeding disorders
depends on severity
carriers / mild can be seen at GDP with review every 2yrs - observed for 2-3hrs following XLA, biopsy etc
moderate / severe should be seen in hospital setting - observed overnight
IBD only undertaken in hospitals
do not give NSAIDs i.e. aspirin so this will inhibit platelet aggregation & increase bleeding
thrombophilia
increases risk of clot development
inherited = protein C/S deficiency, factor V leiden & antithrombin III deficiency
acquired = DVT, OCP, surgery trauma, cancer, pregnancy
where is vitamin k stored
the liver
dental relevance of liver disease
- mild = blood results normal so ptx treated as normal
- moderate = platelet count >100 so shouldn’t be any issue with tx but local measures for haemostasis may need to be accounted for
- severe = lack of many clotting factors, platelet count <100 so XLA & invasive procedures should be undertaken in a hospital setting
warfarin & INR
want consistent INR of 2-4
it will antagonise vit K which is required for synthesis of factors 2 7 9 10, protein C & S
drug interactions with warfarin
potentiating drugs = ACE inhibitors, antibiotics, NSAIDs
inhibiting drugs = epilepsy drugs & alcohol
dental relevance of warfarin
INR must be checked 48hrs before tx, if unstable check 24hrs, avoid IBD if possible, if tx of warfarin is to be stopped for tx wait 72hrs after (12hrs if heparin)
dental relevance of aspirin & clopidogrel
both of these are irreversible for the life of the platelet which is 7 days
if low dose aspirin & clopidogrel used separately there is no effect on post op bleeding but if used together there will so stop 7 days prior to surgery / invasive procedure
risk factors for cardiovascular disease
irreversible - age, sex, family history
behavioural - smoking, alcohol, diet, exercise, obesity
factors managed by drugs - hypertension, hyperlipidaemia, diabetes, stress
drugs that can increase risk - corticosteroids, OCP, sympathomimetrics i.e. adrenaline
drugs that prevent further cardiovascular disease (3)
- anti-platelet
- anti-arrhythmics
- lipid lowering
these help stop build up of atheroma & help keep the rhythm of the heart under control, help to prevent further hypertension, heart arrhythmias & prevent infarction
anti platelet drugs
e.g. aspirin & clopidogrel
widespread atherosclerosis causes more platelet aggregation which can narrow or occlude blood vessels leading to ischaemia / infarction so these drugs are used to decrease total peripheral resistance to decrease BP
lipid lowering drugs
e.g. statins
inhibit cholesterol synthesis in liver reducing blood cholesterol & LDL levels to reduce further build up of atheroma, help to stabilise TPR keeping BP down
these can interact with antifungals & cause myositis
anti arrhythmic drugs
e.g. amiodarone
bock beta receptors in heart preventing increase in heart rate thus reducing cardiac output
these can cause postural hypotension due to decreased heart rate & can worsen heart failure, will also block beta receptors in lungs making asthma more difficult to treat
drugs that reduce current cardiovascular disease (5)
- diuretics
- anti-arrhythmics
- nitrates
- calcium channel blockers
- angiotensin converting enzyme inhibitors
these drugs help reduce BP thus helping to prevent symptoms of disease & prevent further disease occurring
diuretics
e.g. thiazide / loop - furosemide
thiazide; inhibit NaCl cotransporter in DCT of kidney decreasing Na reabsorption so increased fluid passed as urine e.g. chlorothiazide
loop; inhibit NaClK cotransporter in ascending loop of henle
overall reduce blood plasma volume thus reducing cardiac workload & BP helping reduce symptoms of heart failure
side effects are Na/K imbalance if not monitored properly, can cause gout
nitrates
e.g. glyceryl trinitrate
work by releasing nitrous oxide which causes vasodilation throughout the body, veins supplying heart are dilated reducing preload, resistance arteries will dilate reducing workload & oxygen consumption & collateral coronary artery supply will be dilated reducing angina pain
used as a spray sublingually in emergency
calcium channel blockers
e.g. amlodipine
block calcium channels in smooth muscle including the heart slowing conduction (calcium used to lengthen action potentials), causes vasodilation in peripheral blood vessels, both of these decrease BP
side effect - gingival hyperplasia
ACE inhibitors
e.g. prils
inhibit conversion of angiotensin I to angiotensin II which prevents aldosterone release from medulla of adrenal gland meaning that aldosterone will not be used to resorb salt & water leading to reduced salt & water retention which reduces BP
side effects - hypotension & cough
ischaemia & infarction
deficient blood supply to tissue which can lead to hypoxia / necrosis
can be due to atheroma, embolism or thrombosis
ischaemia leads to infarction over time
atheroma
build up of plaque due to accumulation of lipids, smooth muscle proliferation & formation of fibrous tissue
predisposed by hyperlipaemia, smoking, hypertension, diabetes
atheroma leads to arterial narrowing causing angina / intermittent claudication
can cause increased thrombosis which can lead to ischaemia / infarction
can weaken arterial walls causing aneurysm
thrombosis
formation of solid mass from blood constituents in vascular system
predisposed by atheroma, turbulent blood flow, hypercoagulable blood
embolism
vascular transfer of a substance by blood which becomes stuck in a blood vessel distant from the origin
often caused by thromboembolism
thrombus from left side of heart / arteries break off it can cause ischaemia / infarction due to blood flow obstruction
thrombus formed in DVT can cause focal pulmonary infarction / may obstruct main pulmonary arteries from right side of heart causing sudden death
stable v unstable angina
stable = cardiac arteries become ischaemic so not enough oxygen supplied heart under exertion
unstable = randomly occurs with symptoms sometimes mimicking MI, may be rapid deterioration
diagnosing angina
central crushing autonomic nerve pain which is relieved by rest
sometimes a hyperdynamic circulation
angina investigations
ECG - typically normal but on pain often a raised or lowered ST segment, may see raised ST if previous MI
angiography - to view occlusion or narrowing of coronary arteries
echocardiogram
tx for angina
tx required as over time it will lead to infarction
best action is to modify risk factors i.e. stop smoking, improve diet & increase exercise
drug therapy - anti platelet i.e. aspirin to prevent platelet aggregation on atheroma, Ca channel blockers, diuretics, beta blockers, ACE inhibitors to reduce BP, decreasing amount of atherosclerosis forming & reducing load of heart, nitrates e.g. GTN to reduce preload & dilate coronary arteries
surgical therapy - CABG or angioplasty with stenting
PVD
peripheral vascular disease i.e. ischaemia of the tissues named intermittent claudication & affects lower limbs
pain on exertion & relived by rest
MI
complete blockage of 1 of the coronary arteries leading to functional limitation or death
ST segment elevation and after a Q wave will be present
symptoms - pain, nausea, paleness, sweating
signs - increased troponin level
tx of MI
get to hospital as soon as possible
prescribe aspirin to prevent platelet aggregation, beta blockers & Ca channel blockers to slow heart rate reducing O2 demand, ACE inhibitors & diuretics to reduce heart load by reducing BP
angioplasty & stenting preferred to thrombolysis as this is only effective when given early and will cause all clots to break down causing bleeding so contraindicated in liver disease, severe hypertension & pregnancy
again modify risk factors
stroke
infarction to cerebral arteries in the brain caused by embolism from atheroma or cerebral bleed
dental relevance of angina
central crushing chest pain can radiate to jaw
may struggle to get up stairs in dental surgery
LA with adrenaline may cause angina attack due to increased heart rate if accidentally injected into vein
normal sinus rhythm
p wave - atrial depolarisation
qrs complex - ventricular depolarisation
t wave - ventricular repolarisation
during MI ST is raised and in angina it is lowered
atrial fibrillation
no p wave present
high heart rate with irregular beats
same as in MI
ventricular fibrillation
shockable rhythm
irregularly irregular
common causes of bradyarrhythmia
drug induced by beat blockers
heart block
tx of bradyarrhythmia
pacemaker
caution when using ultrasonic scaler as risk of electrical interference
hypertension
normal = 120/80mmHg
hypertension = 140/90mmHg
systolic = pressure when heart pushes blood out
diastolic = pressure when heart rests between beats
if systolic high there is increased stroke risk due to high BP potentially causing aneurysm & rupturing in cerebral veins & arteries
if diastolic high it causes more problems as heart will have to push harder against already high pressure
3 causes of hypertension
- essential hypertension - no specific cause but thought to be due to how endothelial cells react to different stimuli i.e. different genetics cause a different response
- renal artery stenosis (glomerulonephritis) - kidney arteries become blocked / damaged due to atherosclerosis or thromboembolism causing less water to be excreted increasing BP
- endocrine tumour - release different hormones increasing BP e.g. phaeochromocyte tumours cause sudden adrenaline release, conn’s syndrome causes aldosterone release & cushing’s causes cortisol release
diagnosis of hypertension
often go unnoticed
make get TIAs i.e. mini stroke where cerebral arteries will be temporarily blocked by an embolism which is broken down within 24hrs & neurological function returns
outcome of hypertension
can lead to increased atheroma, MI, stroke, PVD & renal failure
as heart will have to work harder against increased BP causing left ventricular hypertrophy which will increase risk of left heart failure especially if heart can no longer pump against increased BP
tx of hypertension
aim to lower BP to <140/90 by modifying risk factors / pharmacological intervention i.e. diuretics, beta blockers, ca channel blockers, ACE inhibitors
heart failure
output of heart not capable of meeting demands of the tissues; can be:
1. low output failure i.e. problem with heart
2. high output failure i.e. problem with the body as a whole
high output failure
heart is pumping correctly & should be supplying tissues but due to issues with the rest of the body the tissues are not receiving enough oxygen to meet their demands. 2 main causes =
1. anaemia - not enough haemoglobin in blood to transport oxygen to tissues
2. thyrotoxicosis - increased thyroxine hormone produced which increases demands of tissues
low output failure
heart is failing as an organ, not pumping enough blood to keep up with demand; defects include; MI & valve disease
have R, L, congestive (both) failure, often it will start with L then lead to R
aetiology of heart failure
multifactorial disease:
- heart muscle disease; includes MI & myocarditis, decreased cardiac output as heart has functional limitation
- pressure overload; diastolic hypertension; heart has to pump harder against already high BP to force blood into peripheral tissues, aortic stenosis; narrowing of aorta so heart uses more pressure
- volume overload; mitral / aortic valve incompetence the efficiency of heart as a pump will be greatly reduced
- arrhythmias; irregular heart rhythm will lead to decreased efficiency of heart i.e. atrial fibrillation
- drugs; beta blockers can decrease HR leading to low output failure
diagnosis of heart failure
LHS - problems with lungs & systolic BP affected causing dyspnoea (fluid in lungs causing breathlessness especially lying down), orthopnoea, tachycardia, low BP/volume/pulse
RHS - increase venous pressure and so diastolic BP leading to swollen ankles, ascites, raised JVP, tender enlarged liver & poor GI tract absorption
tends to be left affected first
tx of heart failure
underlying cause must be treated
in chronic failure inotropes e.g. digoxin taken to increase heart function with negative inotropes e.g. beat blockers stopped
diuretics, ACE inhibitors, nitrates can be used to reduce BP & heart load
in acute heart failure send to hospital where it is treated with oxygen, morphine & furosemide
4 valves of heart
mitral (bicuspid) - left
tricuspid - right
LAB RAT
pulmonary - right
aortic - left
cardiac valve disease
issue with valves of heart
left more likely to be affected due to higher pressure needed; these are the aortic & mitral valves
aetiology of cardiac valve disease (4)
- usually stenosis of valve so it has narrowed & less blood flows through it
- congenital bicuspid aortic valve where tricuspid has only 2 cusps not 3
- after an MI there could be papillary muscle rupture leading to valve incompetence
- rheumatic fever - can lead on to rheumatic heart disease which can cause valve damage; these ptx can require antibiotic prophylaxis