Vascular Flashcards
Peripheral vascular disease
Causes, sx, ix, mx
Causes:
• Smoking
• Diabetes mellitus
• Hypertension
• Hyperlipidaemia, characterised by high total cholesterol and low high-density lipoprotein (HDL) cholesterol levels
• Physical inactivity
• Obesity.
Sx:
Symptoms
• Impaired ability to walk
• Pain in the buttocks and thighs, relieved at rest
Signs
• Pale, cold leg
• Hair loss
• Presence of ulcers
• Poorly healing wounds
• Weak or absent peripheral pulses
Ix:
PAD investigations start with a complete cardiovascular risk assessment, which includes measurements of blood pressure, full blood count, blood glucose, lipids, and an electrocardiogram (ECG).
Specific investigations include the Ankle-Brachial Pressure Index (ABPI). This straightforward, first-line investigation for PAD is conducted by using a Doppler probe to measure the systolic brachial blood pressures of the arms and comparing them with the ankle blood pressures.
The ABPl is computed as follows:
Ankle pressure (on side of interest)/Brachial pressure (on side of interest)
Interpretation of ABPI:
• 1.2: suggests abnormal thickening of vascular walls (typically in diabetes)
• 0.9 - 1.2: Normal
• 0.8 - 0.9: Mild disease
• 0.5 - 0.8: Moderate disease
• <0.5: Severe disease
Imaging investigations may include:
• Duplex arterial ultrasound: beneficial for individuals who might be suitable for revascularisation.
• MR arteriogram: utilised for those who are candidates for revascularisation.
• CT arteriogram: employed in those unsuitable for MR.
• Digital subtraction angiography: typically performed at the time of intervention or for monitoring disease.
Mx:
Cardiovascular risk management:
• Antiplatelet therapy with clopidogrel 75mg once daily (Aspirin is an alternative if clopidogrel is not tolerated or contraindicated).
• Lipid-lowering therapy with atorvastatin 80mg once nightly.
• Optimising glycaemic control in diabetic patients.
• Appropriate management of high blood pressure.
Pain management:
• Naftidrofuryl oxalate, a vasodilator, can alleviate pain in PAD. It should only be prescribed if supervised exercise is ineffective and the patient does not want to be referred for angioplasty or bypass surgery.
Surgical options include:
• Endovascular methods, recommended for small discrete stenosis.
• Surgical bypass, suitable for larger, more extensive stenosis.
• Amputation may be required in cases of critical limb ischaemia unsuitable for other interventions, intractable pain, an unresolving ulcer, or severe loss of function
Abdominal aortic aneurysms
Rf, sx, ix, mx
Enlarged abdominal aorta that exceeds a diameter of 3cm
Rf:
- age
- male
- smoking
- HTN
- FHx
Sx:
- pulsation abdo mass
- abdo or back pain
Ix:
- abdo US (screening at age 65: 3-4.4 yearly, 4.5-5.4 3 monthly, >5.5 surgical intervention)
- CT angiography
- MRA
- bloods (FBC, coag profile, renal function tests, electrolytes)
Mx:
- open repair
- endovascular aneurysm repair
- must be >5.5 cm or increased >5mm over 6 month period
Deep vein thrombosis (DVT)
Causes, sx, ix, mx
Risk factors for DVT can be remembered with the mnemonic THROMBOSIS:
• Thrombophilia
• Hormonal (COCP, pregnancy and the postpartum period, HRT)
• Relatives (family history of VTE)
• Older age (>60)
• Malignancy
• Bone fractures
• Obesity
• Smoking
• Immobilisation (long-distance travel, recent surgery or trauma)
• Sickness (e.g. acute infection, dehydration)
Sx:
• Unilateral erythema, warmth, swelling and pain in the affected area
• Pain on palpation of deep veins
• Distention of superficial veins
• Difference in calf circumference if the leg is affected
• This should be measured 10cm below the tibial tuberosity
• 3cm difference between the legs is significant
Ix:
- wells score (cancer, paralysis, surgery, tenderness, swollen more than 3cm, pitting oedema, history of DVT)
- D-dimer
- Doppler ultrasound
- bloods (FBC, U&E, LFT and coag screen)
Mx:
- DOACs (apixaban) as first line anti coag
- second line is LMW heparin for at least 5 days with a target INR of 2.5
- in unprovoked DVT drop anti coags after 3 months
Acute ischaemic limb
Def, causes, sx, ix, mx
Acute limb ischaemia (ALl) is a severe, symptomatic hypoperfusion of a limb that has been occurring for less than 2 weeks. Although the definition specifies a 2-week period, this condition is considered a surgical emergency and demands urgent intervention, ideally within 4-6 hours.
Causes:
• Thrombosis (40%) - This often results from the rupture of atherosclerotic plaques.
• Embolism (40%) - These are most commonly observed in patients with atrial fibrillation.
• Vasospasm - Such as observed in Raynaud’s phenomenon.
• External vascular compromise:
• Trauma
• Compartment syndrome
Acute limb ischaemia secondary to thrombosis typically has a sub-acute onset and is associated with features of peripheral vascular disease in the contralateral limb. In contrast, ALI secondary to embolisation has a more acute onset and often results from atrial fibrillation.
Sx (6Ps):
• Pulseless
• Painful
• Pale
• Paralysis
• Paraesthesia
• Perishingly cold
Ix:
• Full blood count (FBC)
• Urea and electrolytes (U&E)
• Blood grouping and saving
• Clotting profile
• Electrocardiogram (ECG) - This is particularly useful to detect atrial fibrillation, suggesting an embolic cause for ALI.
Acute limb ischaemia can be further classified according to the Rutherford criteria, which can help stratify management:
• Stage I - Viable limb. There is arterial signal that can be picked up with Doppler.
• Stage lla - Mild sensory deficit and no motor deficit.
• Stage Ilb - Severe sensory deficit. It is usually more than just the toes. There may also be rest pain. There can also be motor deficit. Limb salvage depends on immediate treatment. Fasciotomies are often required.
• Stage III - Irreversibly non-viable limb. Sometimes patients with stage Ill undergo amputation. Very early treatment can rarely result in some degree of reversal.
Mx:
For thrombotic causes, management strategies include:
• Angiography for incomplete ischaemia. This helps map the occlusion site and plan for intervention. Potential endovascular procedures include angioplasty, thrombectomy, or intra-arterial thrombolysis.
• Urgent bypass surgery for complete ischaemia.
For embolic causes, the leg is typically threatened, and immediate embolectomy is required. If embolectomy fails, on-table thrombolysis may be considered.
Note that in cases where the limb is non-viable, amputation may be required. In all cases, the patient should be kept nil by mouth in preparation for potential surgical interventions. Intravenous heparin may be administered to prevent further thrombus propagation, typically after a senior review.
Arterial ulcers
Cause, sx, ix, mx
Cause:
- peripheral arterial disease due to atherosclerosis
Sx:
- occur distally (heel or toe tips)
- small and deep
- punched out margin
- do not bleed or ooze
- weak distal pulses
- skin/hair atrophy
Ix:
- physical exam
- Doppler ultrasound
- angiography
Mx:
- lifestyle changes
- antiplatelets eg. Aspirin or clopidogrel
- statins
- antihypertensives
Surgical site infection
Def, path, rf, sx, ix, mx , prevention
During surgery, skin and/or non-sterile organs are breached, potentially introducing microorganisms into previously sterile spaces. Depending on the number of organisms introduced, the virulance of the pathogen and the host’s immune response, this can cause infection in the post-operative period. Wound infections can be classified by depth: from superficial to deep incisional, and organ/space infection.
Causative organisms:
• Staphylococcus aureus - particularly orthopaedic surgeries
• Escherichia coli - particularly abdominal surgeries
• Pseudomonas aeruginosa
Rf:
• Advanced age
• Frailty
• Comorbidities
• Complexity of surgery
• Immunosuppression
• Smoking status
Sx:
- fever
- local pain
- erythema
- discharge from wound
- abscess
Ix:
- wound swab
- FBC, U&E, CRP
- sepsis 6
Mx:
- Abx
Prevention:
- laminar flow air
- antibiotics prophylaxis
- aseptic technique
- wound closure with appropriate sutures
- dressing changes
Hospital acquired infections
Path, types, mx, prevention
Common pathogens:
- staph aureus
- C. Difficile
- e. Coli
- pseudomonas
Types:
- resp
- UTI
- surgical site
Mx:
- initiate sepsis 6
- pneumonia = co-amoxiclav
- catheter associated UTI = trimethoprim (lower) or cefalexin (upper)
- indwelling line sepsis = vancomycin
Prevention:
- hand hygiene
- PPE
- safe disposal of sharps
- aseptic technique
- regular cleaning
Chronic ischaemic limb
Def, cause, sx, ix, mx
Chronic limb ischaemia is a form of peripheral arterial disease that results in a symptomatic reduced blood supply to the limbs. It is typically caused by atherosclerosis
Sx:
- intermittent claudication
- cramping pain in the calf after walking
- relieved by rest
- cold limb
- arterial ulcers
- absent pulses
Ix:
- buegers test
- ABPI
- Doppler ultrasound
- CTA or MRA
- cardiovascular risk assessment (bp, MB, lipid profile and ECG)
Fontaine classification:
Stage I Asymptomatic
Stage II Intermittent claudication
Stage III Ischaemic rest pain
Stage IV Ulceration or gangrene, or both
Mx:
- lifestyle advice
- 80 mg atorvastatin
- 75 mg clopidogrel
Anaemia
Causes, sx, ix, mx
Causes:
- Blood loss
- Increased destruction (haemolytic)
- Inadequate RBC production (lack of iron, B12, folate, copper, erythropoietin and chronic inflammation)
Ix:
- FBC
- vit b12 and folate
- genetics
- Serum ferritin is acute phase reactant so can show inflammation
- Serum iron reflects iron intake so doesn’t show iron stores
Mx:
- More iron rich food
- Limit cow milk
- Dietician referral
- If menstruation contributes then mefenamic acid
- Address contributing factors
- Iron is better absorbed with vitamin c
