Haematology And Vascular Conditions Flashcards
What is anaemia
Low level of haemoglobin in the blood
What is haemoglobin
A protein found in red blood cells that is responsible for picking up oxygen in the lungs and transporting to to the the cells of the body
How is anaemia subdivided into three categories
Anaemia is initially subdivided into three main categories based on the size of the red blood cell (the MCV). These have different underlying causes:
- Microcytic anaemia (low MCV indicating small RBCs)
- Normocytic anaemia (normal MCV indicating normal sized RBCs)
- Macrocytic anaemia (large MCV indicating large RBCs)
What are the microcytic anaemia causes
T – Thalassaemia A – Anaemia of chronic disease I – Iron deficiency anaemia L – Lead poisoning S – Sideroblastic anaemia
What are the normocytic anaemia causes
A – Acute blood loss A – Anaemia of Chronic Disease A – Aplastic Anaemia H – Haemolytic Anaemia H – Hypothyroidism
What are the macrocytic anaemia causes
Macrocytic anaemia can be megaloblastic or normoblastic. Megaloblastic anaemia is the result of impaired DNA synthesis preventing the cell from dividing normally. Rather than dividing it keeps growing into a larger, abnormal cell. This is caused by a vitamin deficiency
Megaloblastic anaemia is caused by:
- B12 deficiency
- Folate deficiency
Normoblastic macrocytic anaemia is caused by:
- Alcohol
- Reticulocytosis (usually from haemolytic anaemia or blood loss)
- Hypothyroidism
- Liver disease
- Drugs such as azathioprine
What are the signs and symptoms of anaemia
There are many generic symptoms of anaemia:
- Tiredness
- Shortness of breath
- Headaches
- Dizziness
- Palpitations
- Worsening of other conditions such as angina, heart failure or peripheral vascular disease
There are symptoms specific to iron deficiency anaemia:
- Pica: describes dietary cravings for abnormal things such as dirt and can signify iron deficiency
- Hair loss: can indicate iron deficiency anaemia
Generic signs of anaemia:
- Pale skin
- Conjunctival pallor
- Tachycardia
- Raised respiratory rate
Signs of specific causes of anaemia:
- Koilonychia is spoon shaped nails and can indicate iron deficiency
- Angular chelitis can indicate iron deficiency
- Atrophic glossitis is a smooth tongue due to atrophy of the papillae and can indicate iron deficiency
- Brittle hair and nails can indicate iron deficiency
- Jaundice occurs in haemolytic anaemia
- Bone deformities occur in thalassaemia
- Oedema, hypertension and excoriations on the skin can indicate chronic kidney disease
How is anaemia investigated
Initial Investigations:
- Haemoglobin
- Mean Cell Volume (MCV)
- B12
- Folate
- Ferritin
- Blood film
Further Investigations:
- Oesophago-gastroduodenoscopy (OGD) and colonoscopy to investigate for a gastrointestinal cause of unexplained iron deficiency anaemia. This is done on an urgent cancer referral for suspected gastrointestinal cancer.
- Bone marrow biopsy may be required if the cause is unclear
What are the causes of iron deficient anaemia
Insufficient dietary iron
Iron requirements increase (for example in pregnancy)
Iron is being lost (for example slow bleeding from a colon cancer)
Inadequate iron absorption
How is iron deficient anaemia managed
Management involves treating the underlying cause and correcting the anaemia. The anaemia can be treated depending on the severity and symptoms with three methods, that range from fastest to slowest and most invasive to least invasive:
Blood transfusion. This will immediately correct the anaemia but not the underlying iron deficiency and also carries risks.
Iron infusion e.g. “cosmofer”. There is a very small risk of anaphylaxis but it quickly corrects the iron deficiency. It should be avoided during sepsis as iron “feeds” bacteria.
Oral iron e.g. ferrous sulfate 200mg three times daily. This slowly corrects the iron deficiency. Oral iron causes constipation and black coloured stools. It is unsuitable where malabsorption is the cause of the anaemia.
When correcting iron deficiency anaemia with iron you can expect the haemoglobin to rise by around 10 grams/litre per week.
What is an abdominal aortic aneurysm
AKA AAA
Refers to dilation of the abdominal aorta with a diameter of more than 3cm
Often patients first become aware of an aneurysm is when it ruptures, causing life-threatening bleeding into the abdominal cavity
Mortality of a ruptured AAA is ~80%
What are the risk factors for a AAA
Men are affected significantly more often and at a younger age than women Increased age Smoking Hypertension Family history Existing cardiovascular disease
What is the screening process for AAA
All men in England are offered a screening ultrasound scan at age 65 to detect asymptomatic AAA. Early detection of an AAA means preventative measures can stop it from expanding further or rupturing.
Women are not routinely offered screening, as they are at much lower risk. The NICE guidelines (2020) say a routine ultrasound can be considered in women aged over 70 with risk factors such as existing cardiovascular disease, COPD, family history, hypertension, hyperlipidaemia or smoking.
Patients with an aorta diameter above 3cm are referred to a vascular team (urgently if more than 5.5cm).
How do patients with an AAA present
Most patients are asymptomatic and often discovered on routine screening or when it ruptures
Other ways it can present include:
-Non-specific abdominal pain
-Pulsatile and expansile mass in the abdomen when palpated with both hands
-As an incidental finding on an abdominal x-ray, ultrasound or CT scan
How is a AAA diagnosed
Ultrasound: is the usual investigation for establishing the diagnosis
CT angiogram: gives a more detailed picture of the aneurysm and helps guide elective surgery to repair the aneurysm
How is a AAA classified
The severity of the aortic aneurysm depends on the size:
- Normal: less than 3cm
- Small aneurysm: 3 – 4.4cm
- Medium aneurysm: 4.5 – 5.4cm
- Large aneurysm: above 5.5cm
How is a AAA managed
Risk of progression of a AAA can be reduced by treating reversible risk factors:
- smoking cessation
- healthy diet and exercise
- optimising the management of hypertension, diabetes and hyperlipidaemia
Elective surgery:
- involves inserting an artificial graft into the section of the aorta affected by the aneurysm by:
- open repair via laparotomy
- end-vascular aneurysm repair (EVAR) using a stent inserted via the femoral arteries
How does a ruptured AAA present
Severe abdominal pain that may radiate to the back or groin
Haemodynamic instability (hypotension and tachycardia)
Pulsatile and expansile mass in the abdomen
Collapse
Loss of consciousness
How is a ruptured AAA managed
Surgical emergency requiring immediate involvement of experience seniors
Permissive hypotension refers to the strategy of aiming for a lower than normal blood pressure when performing fluid resuscitation because of the theory that increasing the blood pressure may increase blood loss
Haemodynamically unstable patients with a suspected AAA should be transferred directly to theatre. Surgical repair should not be delayed by getting imaging to confirm the diagnosis.
CT angiogram can be used to diagnose or exclude ruptured AAA in haemodynamically stable patients.
In patients with co-morbidities that make the prognosis with surgery very poor, a discussion needs to be had with senior doctors, the patient and their family about palliative care.
What are varicose veins
Distended superficial veins measuring more than 3mm in diameter, usually affecting the legs
What are reticular veins
Dilated blood vessels in the skin measuring less than 1-3mm in diameter
What is telangiectasia
Refers to dilated blood vessels in the skin measuring less than 1mm in diameter
Also known as spider veins or thread veins
How do varicose veins develop
Veins contain valves that only allow blood to flow in one direction, towards the heart. In the legs, as the muscles contract, they squeeze blood upwards against gravity. The valves prevent gravity from pulling the blood back into the feet. When the valves become incompetent, the blood is drawn downwards by gravity and pools in the veins and feet.
The deep and superficial veins are connected by vessels called the perforating veins (or perforators), which allow blood to flow from the superficial veins to the deep veins. When the valves are incompetent in these perforators, blood flows from the deep veins back into the superficial veins and overloads them. This leads to dilatation and engorgement of the superficial veins, forming varicose veins.
What are the risk factors for varicose veins
Increasing age
Family history
Female
Pregnancy
Obesity
Prolonged standing (e.g., occupations involving standing for long periods)
Deep vein thrombosis (causing damage to the valves)
How do varicose veins present
Varicose veins present with engorged and dilated superficial leg veins. They may be asymptomatic or have symptoms of:
- Heavy or dragging sensation in the legs
- Aching
- Itching
- Burning
- Oedema
- Muscle cramps
- Restless legs
- May also have signs and symptoms of chronic venous insufficiency (e.g., skin changes and ulcers).
What is the tap test for varicose veins
Apply pressure to the saphenofemoral junction (SFJ) and tap the distal varicose vein, feeling for a thrill at the SFJ. A thrill suggests incompetent valves between the varicose vein and the SFJ.
What is the cough test for varicose veins
Apply pressure to the SFJ and ask the patient to cough, feeling for thrills at the SFJ. A thrill suggests a dilated vein at the SFJ (called saphenous varix).
What is the trendelenburg’s test for varicose veins
With the patient lying down, lift the affected leg to drain the veins completely. Then apply a tourniquet to the thigh and stand the patient up. The tourniquet should prevent the varicose veins from reappearing if it is placed distally to the incompetent valve. If the varicose veins appear, the incompetent valve is below the level of the tourniquet. Repeat the test with the tourniquet at different levels to assess the location of the incompetent valves.
What is the Perthes test for varicose veins
Apply a tourniquet to the thigh and ask the patient to pump their calf muscles by performing heel raises whilst standing. If the superficial veins disappear, the deep veins are functioning. Increased dilation of the superficial veins indicates a problem in the deep veins, such as deep vein thrombosis.
What is the Duplex ultrasound test for varicose veins
Can be used to assess the extent of varicose veins. It is an ultrasound that shows the speed and volume of blood flow.
How are varicose veins managed
Varicose veins in pregnancy often improve after delivery.
Simple treatment measures include:
- Weight loss if appropriate
- Staying physically active
- Keeping the leg elevated when possible to help drainage
- Compression stockings (exclude arterial disease first with an ankle-brachial pressure index)
Surgical options:
- Endothermal ablation – inserting a catheter into the vein to apply radiofrequency ablation
- Sclerotherapy – injecting the vein with an irritant foam that causes closure of the vein
- Stripping – the veins are ligated and pulled out of the leg
What are potential complications of varicose veins
Prolonged and heavy bleeding after trauma Superficial thrombophlebitis (thrombosis and inflammation in the superficial veins) Deep vein thrombosis All the issues of chronic venous insufficiency (e.g., skin changes and ulcers)
What is peripheral arterial disease
Refers to the narrowing of the arteries supplying the limbs and periphery, reducing the blood supply to these areas. It usually refers to the lower limbs, resulting in symptoms of claudication.
What is intermittent claudication
A symptom of ischaemia in a limb, occurring during exertion and relieved by rest. It is typically a crampy, achy pain in the calf, thigh or buttock muscles associated with muscle fatigue when walking beyond a certain intensity.
What is critical limb ischaemia
The end-stage of peripheral arterial disease, where there is an inadequate supply of blood to a limb to allow it to function normally at rest. The features are pain at rest, non-healing ulcers and gangrene. There is a significant risk of losing the limb.
What is acutel limb ischaemia
Refers to a rapid onset of ischaemia in a limb. Typically, this is due to a thrombus (clot) blocking the arterial supply of a distal limb, similar to a thrombus blocking a coronary artery in myocardial infarction.
What is ischaemia
Refers to an inadequate oxygen supply to the tissues due to reduced blood supply
What is necrosis
Refers to the death of tissue
What is gangrene
Refers to the death of the tissue, specifically due to an inadequate blood supply
What is atherosclerosis
Athero- refers to soft
Sclerosis- refers to hardening
Atherosclerosis is a combination of atheromas (fatty deposits in the artery walls) and sclerosis (the process of hardening or stiffening of the blood vessel walls). Atherosclerosis affects the medium and large arteries. It is caused by chronic inflammation and activation of the immune system in the artery wall. Lipids are deposited in the artery wall, followed by the development of fibrous atheromatous plaques.
What do atherosclerotic plaques cause
Stiffening of the artery walls, leading to hypertension (raised blood pressure) and strain on the heart (whilst trying to pump blood against increased resistance)
Stenosis, leading to reduced blood flow (e.g., in angina)
Plaque rupture, resulting in a thrombus that can block a distal vessel and cause ischaemia (e.g., in acute coronary syndrome)
What are the risk factors of atherosclerosis
Non-modifiable risk factors:
- Older age
- Family history
- Male
Modifiable risk factors:
- Smoking
- Alcohol consumption
- Poor diet (high in sugar and trans-fat and low in fruit, vegetables and omega 3s)
- Low exercise / sedentary lifestyle
- Obesity
- Poor sleep
- Stress
Medical co-morbidities increase the risk of atherosclerosis and should be carefully managed to minimise the risk:
- Diabetes
- Hypertension
- Chronic kidney disease
- Inflammatory conditions such as rheumatoid arthritis
- Atypical antipsychotic medications
What are the potential end results of atherosclerosis
Angina Myocardial infarction Transient ischaemic attack Stroke Peripheral arterial disease Chronic mesenteric ischaemia
What are the features of critical limb ischaemia
6 Ps
- Pain (burning pain that is worse at night when the leg is raised as gravity no longer helps pull blood into the foot)
- Pallor
- Pulseless
- Paralysis
- Paraesthesia (abnormal sensation or “pins and needles”)
- Perishing cold
What is Leriche syndrome
Leriche syndrome occurs with occlusion in the distal aorta or proximal common iliac artery. There is a clinical triad of:
- Thigh/buttock claudication
- Absent femoral pulses
- Male impotence
What are the signs on examination of PVD
Look for risk factors:
- Tar staining on the fingers
- Xanthomata (yellow cholesterol deposits on the skin)
Looks for signs of cardiovascular disease:
- Missing limbs or digits after previous amputations
- Midline sternotomy scar (previous CABG)
- A scar on the inner calf for saphenous vein harvesting (previous CABG)
- Focal weakness suggestive of a previous stroke
The peripheral pulses may be weak on palpation: -Radial -Brachial -Carotid -Abdominal aorta -Femoral -Popliteal -Posterior tibial -Dorsalis pedis Doppler to accurately assess the pulses when they are difficult to palpate.
Signs of arterial disease on inspection are:
- Skin pallor
- Cyanosis
- Dependent rubor (a deep red colour when the limb is lower than the rest of the body)
- Muscle wasting
- Hair loss
- Ulcers
- Poor wound healing
- Gangrene (breakdown of skin and a dark red/black change in colouration)
On examination, there may be:
- Reduced skin temperature
- Reduce sensation
- Prolonged capillary refill time (more than 2 seconds)
- Changes during Buerger’s test
What is Beurger’s test
Assesses peripheral arterial disease in the leg
Two parts to the test:
1. Patient lies on back and lift patient’s legs to an angle of 45 degrees at the hip. Hold for 1-2 mins, looking for pallor, which indicates the arterial supply is not adequate to overcome gravity, suggesting peripheral arterial disease. Beurger’s angle refers to the angle at which the leg is pale due to inadequate blood supply
2. Sit patient up with their legs hanging over the side of the bed. blood will flow back into the legs assisted by gravity. In healthy legs will remain a normal pink colour but in PAD will go:
-Blue initially, as the ischaemic tissue deoxygenates the blood
-Dark red after a short time, due to vasodilation in response to the waste products of anaerobic respiration (aka rubor)
What are arterial ulcers
Arterial ulcers are caused by ischaemia secondary to an inadequate blood supply. Typically, arterial ulcers:
- Are smaller than venous ulcers
- Are deeper than venous ulcers
- Have well defined borders
- Have a “punched-out” appearance
- Occur peripherally (e.g., on the toes)
- Have reduced bleeding
- Are painful
What are venous ulcers
Venous ulcers are caused by impaired drainage and pooling of blood in the legs. Typically, venous ulcers:
- Occur after a minor injury to the leg
- Are larger than arterial ulcers
- Are more superficial than arterial ulcers
- Have irregular, gently sloping borders
- Affect the gaiter area of the leg (from the mid-calf down to the ankle)
- Are less painful than arterial ulcers
- Occur with other signs of chronic venous insufficiency (e.g., haemosiderin staining and venous eczema)
How is peripheral vascular disease investigated
Ankle-brachial pressure index (ABPI)
Duplex ultrasound – ultrasound that shows the speed and volume of blood flow
Angiography (CT or MRI) – using contrast to highlight the arterial circulation
What is ankle-brachial pressure index
Ankle-brachial pressure index (ABPI) is the ratio of systolic blood pressure (SBP) in the ankle (around the lower calf) compared with the systolic blood pressure in the arm. These readings are taken manually using a Doppler probe. For example, an ankle SBP of 80 and an arm SBP of 100 gives a ratio of 0.8 (80/100).
Results:
- 0.9 – 1.3 is normal
- 0.6 – 0.9 indicates mild peripheral arterial disease
- 0.3 – 0.6 indicates moderate to severe peripheral arterial disease
- Less than 0.3 indicates severe disease to critical ischaemic
An ABPI above 1.3 can indicate calcification of the arteries, making them difficult to compress. This is more common in diabetic patients.
How is intermittent claudication managed
Lifestyle changes are required to manage modifiable risk factors (e.g., stop smoking). Optimise medical treatment of co-morbidities (such as hypertension and diabetes).
Exercise training, involving a structured and supervised program of regularly walking to the point of near-maximal claudication and pain, then resting and repeating.
Medical treatments:
- Atorvastatin 80mg
- Clopidogrel 75mg once daily (aspirin if clopidogrel is unsuitable)
- Naftidrofuryl oxalate (5-HT2 receptor antagonist that acts as a peripheral vasodilator)
Surgical options:
- Endovascular angioplasty and stenting
- Endarterectomy – cutting the vessel open and removing the atheromatous plaque
- Bypass surgery – using a graft to bypass the blockage
What is end-vascular angioplasty and stenting
Involve inserting a catheter through the arterial system under x-ray guidance. At the site of the stenosis, a balloon is inflated to create space in the lumen. A stent is inserted to keep the artery open. Endovascular treatments have lower risks but might not be suitable for more extensive disease.
How is critical limb ischaemia managed
Patients with critical limb ischaemia require urgent referral to the vascular team. They require analgesia to manage the pain.
Urgent re-vascularisation can be achieved by:
- Endovascular angioplasty and stenting
- Endarterectomy
- Bypass surgery
- Amputation of the limb if it is not possible to restore the blood supply
How is acute limb ischaemia managed
Patients with acute limb ischaemia need an urgent referral to the on-call vascular team for assessment.
Management options include:
- Endovascular thrombolysis – inserting a catheter through the arterial system to apply thrombolysis directly into the clot
- Endovascular thrombectomy – inserting a catheter through the arterial system and removing the thrombus by aspiration or mechanical devices
- Surgical thrombectomy – cutting open the vessel and removing the thrombus
- Endarterectomy
- Bypass surgery
- Amputation of the limb if it is not possible to restore the blood supply
What is cervical lymphadenopathy
Lymph nodes that are abnormal in size, consistency or number.
Can be localised, regional or generalised
What are the differentials for suspected cervical lymphadenopathy
CHICAGO Cancer Hypersensitivity Infections Collagen vascular disease Atypical lymphoproliferative disorders Granulomatous disease Other (miscellaneous)
How is cervical lymphadenopathy treated
If common, mild swelling, there are a few options available to help manage it either directly or indirectly, such as:
- antibiotics
- antivirals
- NSAIDs
- adequate rest
- warm and wet washcloth compress
If the lymph nodes are swelling because of cancerous growth, treatment may include:
- chemotherapy
- irradiation therapy
- surgery to remove the lymph node
What do cervical lymph nodes do
Lymph nodes are small encapsulated units in the lymphatic system which filter lymph.
Lymph is a fluid responsible for transporting lymphocytes (a type of white blood cell) all throughout the body’s lymphatic vessel system
Cervical lymph nodes, like the rest of the body's lymph nodes, are responsible for fighting infection by attacking and destroying germs that are carried into the node through lymph fluid. After this filtering process is complete, any leftover fluid, salts and proteins re-enter the blood stream Other roles: -filter lymphatic fluid -manage inflammation -trap cancer cells
Lymph nodes can occasionally swell and cause discomfort, they’re essential to a healthy body and proper immune functioning
What causes swollen cervical lymph nodes (lymphadenopathy)
Bronchitis Common cold Ear infection Scalp infection Strep throat Tonsilitis
