Vascular Flashcards
Method to monitor heparin infusion
Activated Partial Prothromboplastin TIme (aPTT)
Goal: maintain range of 1.5-2.5 times the patient’s aPTT baseline value
Measured 6 hourly initially, then 24 hourly once at therapeutic range
Father with history of AAA at 60
Management
20% higher lifetime risk of developing AAA
Ultrasound screening for men and women > 50 years old with family history of AAA
CTA only if AAA present and if surgery needed; not the ideal test.
Which sign of ALI requires immediate surgical treatment?
Key diagnosis of complete ischaemia warranting urgent surgery:
Paralysis
- unable to wiggle toe or fingers
Mortality rate of ruptured AAA
~80%
Urgent surgical repair of AAA when > 5.5cm
50% of PAD patients are asymptomatic; only 10-15% have symptoms.
What is the most common symptoms?
How to diagnose?
Management
Intermittent Claudication (IC)
- Symptomatic pts have worse prognosis.
Diagnosis
1. History, clinical examination
2. Initial diagnostic tool: ankle-brachial index (ABI) measurement
No need for US Doppler/CTA if no endovascular or open surgery planned.
DSA - gold standard for imaging peripheral arteries, but rarely used cause invasive.
Management
- First: smoking cessation if there is
- Surgery
What is helpful as a DVT prophylaxis for a hospitalised patient?
Enoxaparin (Clexane)
- Subcutaneous injection 40mg OD
- Found to prevent VTE without causing serious bleeding complications.
- In patients with renal failure, reduce dose to 20mgOD
Management for newly diagnosed peripheral artery disease
- Antiplatelet medication (aspirin or Clopidogrel) ONLY IF there is risk of CVS disease
- Anticholesterol medication even in the absence of dyslipidaemia
- Antihypertensive (ramipril or any other ACEI or ARBs)
- Supervised exercise program
Pulmonary Embolism or DVT in a Pregnant Woman
Diagnosis
V/Q scan for PE (after confirming CXR is normal)
US Doppler for DVT
ALI by femoral artery occlusion by an embolus
SSX
Management
Pain, pallor, paraesthesia, pulselessness, paralysis, perishing cold
Emergency embolectomy under LA/GA after giving IV Heparin
- reversible within 4 hours
- irreversible after 6 hours
[If CLI, arterial bypass is helpful; Amputation only if presence of irreversible changes]
Non-healing DFU in the presence of PVD
Management
- Conservative management
- If fail —> REVASCULARISATION with angioplasty and endovascular stunting
- most appropriate to restore blood supply - Reduce cardiovascular events: antiHTN + antiplatelet
- If infection, antibiotics
AAA
Initial imaging
When to refer?
Physical examination —> ultrasound
Refer to vascular surgeons when AAA > 5cm
[CTA with contrast for evaluation and if planning elective repair]
4.5 AAA on aortic US
Management?
Repeat US in 12 months
Recommendations:
3 - 3.9cm: every 24 months
4 - 4.5cm: every 12 months
4.6 - 5.0cm: every 6 months
> 5.0cm: every 3 months
When to refer CLI patient to vascular surgeon?
- Rest pain
- Ischaemic ulceration
- Gangrene
- Claudication symptoms – limiting life and work, no improvements with conservative management after 6 months
Revascularisation required to prevent limb loss.
- endovascular angioplasty or stenting
- open surgical reconstruction by bypass or endarterectomy
Internal carotid artery 90% stenosed
Management?
Carotid endarterectomy
- can reduce stroke!!!
Start aspirin after endarterectomy.
Reperfusion Injury
Features?
- Acute renal failure
- Increased CK levels
- Hyperkalaemia
- Myoglobinaemia
- Metabolic acidosis
These metabolic complications can cause death
Most common cause of ALI
Thrombosis
Even native coronary vessels or bypass grafts can get blocked due thrombosis (less common with embolus)
[Other causes: smoking, congestive cardiac failure, embolism, vasculitis, etc.]
Modality of choice for screening and surveillance of AAA
Ultrasound
AAA screening
- family history
Vs - no family history
- family history: Men < 55, women < 60
- no family history: Men < 65, women < 70
No regular screening in Australia
When should an AAA case be referred to a vascular surgeon STAT?
When it’s leaking/ruptured!
Clinical triad: abdominal and/or back pain, pulsatile abdominal mass, hypotension
Next step to making the diagnosis = To confirm the diagnosis
… of acute arterial occlusion and extent of blockage:
Urgent CT angiogram (gold standard investigation — confirmatory!)
Clinical features of chronic obstructive arterial disease
- intermittent claudication
- reproducible calf pain with activity that is relieved by rest
- shiny, hyperpigmented skin
- hair loss and ulceration on the legs
- thickened nails
- muscle atrophy
- vascular bruit
- poor pulses (HALLMARK)
Versus 6Ps of ALI
Rest pain present in PVD
DDX/Disease is called?
Critical Limb Ischaemia
Requires revascularisation to prevent limb loss
Refer STAT
Management of Superficial Thrombophlebitis
Due to
- IV infusion
- spontaneously
Self-limiting condition
May be complicated by DVT or PE in high-risk patients for VTE
- IV infusion: treat with topical/oral NSAIDs
- Spontaneously: LMWH for 4 weeks and monitor for VTE
Enoxaparin (aka LMWH)
Enoxaparin (aka LMWH)
Best anticoagulation on second-day post surgery for patients at a high risk of developing VTE (has h/o DVT)
ENOXAPARIN (LOW MOLECULAR WEIGHT HEPARIN) —> Warfarin after 1-2 days.
Can cease LMWH when INR is at therapeutic range.
Varicose Veins
- dilated superficial veins
CEAP Classification is used for grading severity of venous disease
When to refer to Vascular Team?
Guidelines: above CEAP 3 only refer to vascular team.
Oedema = CEAP 3 can manage in GP as treatment is often conservative
- compressive therapy
- diet/smoking cessation etc.
Venous Duplex Ultrasound*
ABI > 0.6 and palpable pulses usually means compressive therapy
Best initial treatment for DVT
Injectable heparin (unfractionated or LMWH) initially
Followed by Warfarin within 1-2 days
Then test daily INR
Once INR 2-3,
Stop heparin and continue warfarin for 6 months
Chronic Venous Leg Ulcer due to Chronic Venous Insufficiency
And
Compression Stockings
Compression increases ulcer healing rates.
Multicomponent system > single component system
Elastic component > inelastic component
Easily removed by user - in case of pain
Contraindicated if:
ABPI < 0.8 (arterial)
Caution if:
diabetic with peripheral neuropathy - unable to detect increasing pain
Fibromuscular Dysplasia - can result in stenosis of the renal arteries and hypertension
Commonly affecting women in their 20s and 40s
What to do if renal artery stenosis is involved?
Do Percutaneous Transluminal Angioplasty - mainstay therapy.
However if atherosclerotic type, may see better use in taking ACEI or antihypertensive drugs.
UFH or LMWH preferred for DVT
UFH
- safe to use on unstable patients
- easily reversible with protamine sulfate
Driving post aortic aneurysm or cardiac valvular repair
Unfair to drive private car for 4 weeks, 3 months for commercial car
What to use to CONFIRM DVT?
Duplex Doppler Ultrasound
MRI for suspected caval and iliac venous thrombosis, especially in pregnancy
Indications for inferior vena cava filter for patients with thromboembolism
- Absolute contraindication to therapeutic anticoagulation.
- Failure of anticoagulation when there is acute proximal venous thrombosis.
It is inserted percutaneously via femoral or jugular approach and is usually positioned below the renal veins.
