Acute limb Ischemia causes examination AHA guidelines

1. Acute Limb Ischemia
Dr Farrukh Masood
Postgraduate Resident,
CPEIC Multan

2. Acute Limb Ischemia
• Definition
 Acute (<2 wk), severe hypoperfusion of the limb characterized by
these features: pain, pallor, pulselessness, poikilothermia (cold),
paresthesias, and paralysis

3. Signs & Symptoms
• Pain distal to site of occlusion more on exertion or when limb is
against gravity
• Numbness/Parasthesias
• Cyanosis

8. Classification

9. Etiology
• Embolism
• Thrombosis in situ
• Dissection
• Trauma
• Hypercoagulablity

10. Embolism
• Source of emboli arise from
• Left ventricle
• Paradoxical emboli
• Prosthetic valvular diseases
• Atrial fibrillation
• Atrial myxomas
• Aneurysms of Aorta or peripheral vessels

11. Thrombosis in situ
• Thrombosis in situ occurs in
• Atherosclerotic peripheral arteries
• Infrainguinal bypass grafts(most common)
• Peripheral artery aneurysms,
• Normal arteries of patients with hypercoagulable states
• In patients with PAD, thrombosis in situ may complicate plaque
rupture and cause acute arterial occlusion and limb ischemia

12. Systemic disorders
• Acquired thrombophilic disorders such as antiphospholipid antibody
syndrome,
• Heparin-induced thrombocytopenia
• Disseminated intravascular coagulation, and myeloproliferative
diseases.
• Inherited thrombophilic disorders such as activated protein C
resistance (factor V Leiden), prothrombin G20210 gene mutation, or
deficiencies of antithrombin III and protein C and S

14. Workup
• Baseline
• Coagulation profile
• Echo

15. Ankle to brachial Index

21. MANAGEMENT
• Legs should be below chest level to increase perfusion by hydrostatic
pressure
• Relieve pain
• Heparinize (Loading dose 75-100IU/kg approx. 5000IU) followed by
18IU /kg/hr infusion(1000U)
• Keep Aptt 2-2.5 times of control
• Categorize patient as viable,threatened or irreversible.
• Revascularization is indicated when the viability of the limb is
threatened or when symptoms of ischemia persist.
• Treat the etiology of occlusion

22. • Catheter-directed intra-arterial thrombolysis plus thrombectomy is an
initial treatment option for patients with either category I or II acute
limb ischemia if they have no contraindication to thrombolysis.
• The thrombolytic regimens currently used include the recombinant
tissue plasminogen activators alteplase, reteplase, and tenecteplase.
Catheter-based thrombolytic therapy should generally be continued
for 24 to 48 hours to achieve optimal benefit and to limit the risk for
bleeding. Adjuvant use of platelet glycoprotein IIb/IIIa inhibitors
shortens thrombolysis time but does not improve outcome.

23. Management PEARLS
• Catheter-based thrombolysis is an appropriate initial option in patients with
viable or marginally threatened limbs and when the ischemia is of less than 14
days' duration, whereas
• Surgical revascularization is more appropriate in those with immediately
threatened limbs and in those whose symptoms have lasted for more than 14
days.
• Patients with irreversible injury require amputation
• Long-term anticoagulant therapy is usually indicated for patients with an embolic
source
• For patients with symptomatic PAD who develop ALI from thrombotic
complications in the limbs (e.g., graft occlusion, stent thrombosis, in situ
thrombosis), intensive antiplatelet therapy may be more effective.

25. Complications
• Limb Loss
• Compartment syndrome
• Sepsis
• Hyperkalemia
• Rhabdomyolysis leading to AKI

26. AHA/ACCF Guidelines
COR LOE
I 1. Patients with ALI should be emergently evaluated by a clinician with sufficient experience to assess limb viability and
implement appropriate therapy.
C
2. In patients with suspected ALI, initial clinical evaluation should rapidly assess limb viability and potential for salvage
and does not require imaging.
C
3. In patients with ALI, systemic anticoagulation with heparin should be administered unless contraindicated. C
4. In patients with ALI, the revascularization strategy should be determined by local resources and patient factors (e.g.,
etiology, degree of ischemia).
C
5. Catheter-based thrombolysis is effective for patients with ALI and a salvageable limb. A
6. Amputation should be performed as the first procedure in patients with a nonsalvageable limb. C
7. Patients with ALI should be monitored and treated (e.g., fasciotomy) for compartment syndrome after
revascularization.
C
8. In the patient with ALI, a comprehensive history should be obtained to determine the cause of thrombosis and/or
embolization.
C
IIa 1. In patients with ALI with a salvageable limb, percutaneous mechanical thrombectomy can be useful as adjunctive
therapy to thrombolysis.
B
2. In patients with ALI due to embolism and with a salvageable limb, surgical thromboembolectomy can be effective. C
3. In the patient with a history of ALI, testing for a cardiovascular cause of thromboembolism can be useful. C
IIb The usefulness of ultrasound-accelerated catheter-based thrombolysis for patients with ALI with a salvageable limb is
unknown
C

27. Take Home Message
• Acute Limb Ischemia is an emergency .Always revascularize it within
6hrs otherwise