Peripheral Vascular Disease (PAD) Flashcards
(33 cards)
What is acute arterial insufficiency?
Acute occlusion/rupture of a peripheral artery.
Where does acute arterial insufficiency generally affect?
Lower > upper extremity
Femoropopliteal > aortoiliac
What is the aetiology of acute arterial insufficiency?
Embolus, thrombus, trauma, idiopathic.
Less common: pro-coagulant state, thrombosed aneurysm, dissection, fibromuscular hyperplasia, arteritis, entrapment, advential cysts.
What are the features supportive of cardiac embolus causing acute arterial insufficiency?
-History of MI
What are the clinical features of acute arterial insufficiency?
- Pain: absent in 20%
- Pallor
- Paresthesia
- Paralysis/power loss
- Polar (cold)
- Pulselessness (not reliable)
How should acute arterial insufficiency be investigated?
CXR, ECG, arteriography
Mx acute arterial insufficiency?
- Immediate heparinization w/5000IU bolus (APTT >60s)
- Absent power/sensation: immediate revascularisation
- Present power/sensation: work up (inc angio)
- Progress to embolectomy/ thrombectomy/ amputation
- Commence warfarin d1 post op for 3/12
What are the complications of acute arterial insufficiency?
- Compartment syndrome (prolonged ischaemia)
- Renal failure and multi organ system failure due to ischaemic muscle
What is the aetiology of chronic arterial insufficiency?
Predominately atherosclerosis; usually affects lower extremities.
What are the RFx for chronic arterial insufficiency?
Major: smoking, DM, hyperhomocysteinemia
Minor: HTN, hyperlipidemia, FHx, obesity, sedentery life, male gender
What are the clinical features of chronic arterial insufficiency?
- Claudication
- Pulses may be absent
- Bruits may be present
- Signs of poor perfusion
- Other signs of atherosclerosis (IHD, impotence, splanchnic ischaemia)
What are the signs of poor arterial perfusion?
- hair loss
- hypertrophic nails
- atrophic muscle
- skin ulcerations and infections
- poor capillary refill
- prolonged pallor with elevation and rubor on dependency
- venous troughing
Ddx of chronic arterial insufficiency?
- OA: worse at night, varies day-day.
- Neurogenic claudication (due to spinal stenosis/radiculopathy)
- Varicose veins
- Inflammatory (Buerger’s disease, Takayasu’s arteritis)
- Other: popliteal entrapment, radiation injury, trauma
What are the non-invasive Ix of chronic arterial insufficiency?
-ABI:
What are the invasive Ix of chronic arterial insufficiency?
-Arteriography: superior resolution (to MR/CT), better for tibial arteries.
What are the indices for ABI?
Ankle-Brachial Index: >1.2: suspect wall calcification >0.95: normal 0.85-0.94: Mild 0.5-0.84: Mod 0.26-0.49: Severe
Conservative treatments of chronic arterial insufficiency?
- RFx mod: smoking cessation, manage HTN/ hyperlipidemia / DM
- Exercise: improves collaterals / O2 extraction by muscle
- Foot care: esp in DM.
Pharmacotherapy for Mx chronic arterial insufficiency?
- Anti-platelets: e.g. clopidogrel
- Cilostazol: cAMP phosphodiesterase inhibitor with anti-platelet and vasodilatory effects. Improves walking distance
- Pain relief: opiate analgesia, NSAIDs
Surgical Mx of chronic arterial insufficiency?
- Endovascular (stenting/ angioplasty)
- Endarterectomy: remove plaques with patch repair (usually distal aorta/ common femoral)
- Bypass graft
- Chemical sympathectomy (EtOH injected into nerve plexus; rarely effective)
- Amputation
What are the indications for surgical Mx of chronic arterial insufficiency?
Pain interferes with lifestyle, rest pain, night pain, pre-/gangrene.
What are the sites of bypass grafts in chronic arterial insufficiency?
- Aortofemoral
- Axillofemoral
- Femoropopliteal
- Distal arterial
Prognosis for Pts with claudication?
-Conservative Mx: 60-80% improve, 20-30% same, 5-10% deteriorate
If critical limb ischaemia = high risk of limb loss.
What is claudication?
Ischaemic pain in exercising muscles: imbalance b/w demand of muscle and ability to maintain aerobic metabolism -> switch to anaerobic metabolism -> lactic acid build up -> aching discomfort.
Clinical features of claudication?
- Calf pain on exertion (+/- thigh or buttock)
- Onset/severity related to workload
- Relieved with rest
- Reproducible
