CARDIOVASCULAR MODULE:
ARTERIAL OCCLUSIVE DISORDER
Adult Medical-Surgical Nursing
Peripheral Arterial Occlusive Disorder is a disruption of the peripheral arterial circulation obstructing the flow of oxygenated blood to the tissues
It may occur as an acute emergency
It may be gradual, progressive and chronic
Arterial Occlusive Disorder: Description
Acute Peripheral Vascular Occlusion:
Acute Vascular Occlusion: Aetiology
The artery is blocked by:An embolism (the most frequent cause) from: An aneurysmInfective endocarditisMyocardial infarctionMitral valve disease/ atrial fibrillationProsthetic heart valvesLocalised trauma
Acute Vascular Occlusion: Pathophysiology
An embolism from the left side of the heart or from an aneurysm passes to the peripheries: (the limbs or mesenteric arteries)
The embolism lodges at a site of arterial branching or atherosclerotic narrowing*
This impairs or cuts off the blood supply distal to the occlusion → ischaemia
May lead to infarction of the tissue
(*Also a thrombus may form at an atherosclerotic site with the same result)
Clinical Manifestations
Sudden onset of: (6 “p” s)PainPallorPulselessnessParaesthesiaParalysisPoikilothermia (cool to touch)→ tissue discoloration of affected limb →
gangrene
Acute Vascular Occlusion: Diagnosis
Acute emergency
Diagnosis from history and clinical picture
Doppler Ultrasound
Emergency Treatment
Early treatment to remove embolus/clot and re-establish circulation
Anticoagulation to prevent further extension of clot or more emboli
Embolectomy by balloon catheters distal and proximal to clot or
Surgery: “Thrombo-endarterectomy”: removal of embolus, and stent or graft to keep artery patent
Thrombolytic drug may be possible if very recentAnticoagulants or anti-platelet aggregation drugs
long-term
Follow-up and Long-term Care
Follow-up angiogram to ensure full patency
Long-term anticoagulant or antiplatelet therapy (to prevent recurrence)
INR during anticoagulation
Treat the cause if appropriate
Nursing Responsibilities
ICU post-op: Bedrest with initial immobility of the affected
limbMonitor anticoagulant therapyMonitor vital signs and fluid balanceMonitor:Colour, temperature, sensation, mobility and
pulses of affected limb post-operatively*Observe arterial wound dressing very
carefully (risk of major haemorrhage)
Chronic Peripheral Arterial Occlusive Disease (PAD):
Chronic PAD: Description
A progressive insidious narrowing and eventual occlusion of the peripheral arteries to the extremities, usually the legs
Occurs in men more than womenAge group 60 - 80 years
Arteries affected are aorto-iliac, femoral, popliteal, tibial, peroneal
Chronic PAD: Pre-disposing Factors
Smoking (most important)*HyperlipidaemiaHypertensionDiabetes Mellitus (macrovascular disease –
accelerated atherosclerosis)Obesity and sedentary lifestyleFamily tendency
Chronic PAD: Pathophysiology
Atherosclerosis:Leads to gradual thickening of the intima and
media of the arteries and narrowing and occlusion of the vessel lumen
Tends to be segmented with good patches between atherosclerotic narrowing
Gradual development of collateral circulation because of increasing ischaemia to distal tissues
Ischaemia can lead to ulceration and gangrene (although collateral circulation may prevent this)
Chronic PAD: Clinical Manifestations
Note:When symptoms occur there is already 75%
narrowing of the arteries
Chronic PAD: Clinical Manifestations
Calf pain on exercise “intermittent claudication” (lactic acid formation) → later:
Pain at rest (mainly feet and toes from nerve ischaemia)
Pain is felt more at nightPain relieved by legs dangling below the
patient to increase the blood supply by gravity
Clinical Manifestations (continued)
Paraesthesia:Numbness and tingling, burning Shooting pains to toes and feetPallor: blanching on elevationHyperaemia: red or bluish dusky skin when
limbs dependent Shiny skin with loss of hairPulses weak or absentSkin and tissue atrophy: poor healingIschaemic ulcers on bony toes → gangrene
Chronic PAD: Diagnosis
Doppler ultrasound: velocity of blood flow
Duplex imaging: Doppler mapping
Segmental BP: (at thigh, calf, ankle): should be the same as brachial. As disease progresses leg BP ↓
Angiography: aorta and femoral arteries assessed prior to intervention or surgery
MRI
Chronic PAD: Management
This a chronic progressive disease formerly with no treatment apart from palliative care
VasodilatorsAnalgesia Exercise encouraged as condition allowsSurgery* may be considered for severe and
disabling claudication to avoid risk of amputation: Endarterectomy, By-pass Graft or Stent
(the patient’s overall health is an important consideration)* Anti-platelet cover if graft/ stent
Chronic PAD: Nursing Considerations
Gentle exercise encourages development of collateral circulation
Encourage to avoid smokingAvoid obesityKeep feet and legs warm and cleanObserve for potential ulcers If surgical intervention: post-operative initial
immobility of affected limbSpecial monitoring of pulses, colour, sensation
and temperature of both limbs (to compare)