This presentation gives latest (2016) guidelines regarding acute limb ischemia (ALI), published in Journal of American College of Cardiology (JACC) in March 2017

1. 2016 AHA/ACC Lower Extremity PAD Guideline
Jibran Mohsin
Resident, Surgical Unit I
SIMS/Services Hospital, Lahore

2. J Am Coll Cardiol. 2017 Mar 21;69(11):e71-126.

3. Components
• PAD (Peripheral arterial disease)
• CLI (Critical Limb ischemia)
• ALI (Acute Limb ischemia)

4. ACUTE LIMB ISCHEMIA

5. Definition
• Acute Limb Ischemia (ALI)
• Acute (<2 wk), severe hypoperfusion of the limb characterized by these
features
• Pain
• Pallor
• Pulselessness
• Poikilothermia(cold)
• Paraesthesias, and
• Paralysis
• 3 categories

6. Categories Class Sensory loss Motor loss Capillary refill Arterial flow
(Doppler)
Venous
flow
(Doppler)
Tissue loss
Viable (not
immediately
threatened)
I No No Audible Audible Minor
Threatened
(salvageable)
II a (marginally
threatened)
Limited to toes if
present
No muscle
weakness
Slow-to-intact Inaudible audible Minor
II b (immediately
threatened)
> Toes and with
rest pain
Mild-moderate
muscle
weakness
slow-to-absent
Irreversible
(nonsalvageabl
e)
III Profound
sensory loss,
Anesthetic
profound
muscle
weakness or
paralysis (rigor)
Inaudible inaudible Major tissue
loss
inevtible
Permanent nerve damage
inevitable

9. Clinical Presentation of ALI:
Recommendations
• Patients with ALI should be emergently evaluated by a clinician with
sufficient experience to
1. assess limb viability and
2. implement appropriate therapy.

10. Clinical Presentation of ALI:
Recommendations
• In patients with suspected ALI, initial clinical evaluation should rapidly
assess limb viability and potential for salvage and does not require
imaging

11. Medical Therapy for ALI: Recommendations
• In patients with ALI, systemic anticoagulation with heparin should be
administered unless contraindicated.
(Heparin (generally IV UFH) is given to all patients acutely. This can stop thrombus propagation and may provide an
anti-inflammatory effect that lessens the ischemia)
(in case of HIT and thrombosis direct thrombin inhibitor)

12. Revascularization for ALI: Recommendations
• In patients with ALI, the revascularization strategy should be
determined by local resources and patient factors (e.g., etiology and
degree of ischemia)
(Emergently vs urgent)
(Catheter-directed thrombolysis vs surgical thromboembolectomy)
RAPID RESTORATION of arterial flow with least risk to patient

13. Revascularization for ALI: Recommendations
• Catheter-based thrombolysis is effective for patients with ALI and a
salvageable (viable or marginally threatened) limb
(Particularly in setting of recent occlusion, thrombosis of synthetic grafts, and stent thrombosis)

14. Revascularization for ALI: Recommendations
• Amputation* should be performed as the first(index) procedure in
patients with a nonsalvageable (class III) limb
(low potential of limb salvage ad risk of reperfusion syndrome and associated MOF)
*may be deferred if pain under control and no infection and meets with patients goals

15. Revascularization for ALI: Recommendations
• Patients with ALI should be monitored and treated (e.g., fasciotomy) for compartment syndrome
after revascularization
(due to reperfusion causing cellular edema)
Indications
1. Raised intra compartment pressure (> 30 mmHg) – not always easily accessible
2. Clinical: increased pain, tense muscle, or nerve injury
3. Category IIb ischemia for whom time to revascularization is > 4 hours

16. Revascularization for ALI: Recommendations
• In patients with ALI with a salvageable limb, percutaneous mechanical
thrombectomy (PMT) can be useful as adjunctive therapy to
thrombolysis (pharmacologic therapy)

18. Revascularization for ALI: Recommendations
• In patients with ALI due to embolism* and with a salvageable limb, surgical
thromboembolectomy can be effective
*arterial embolism with absent pulse ipsilateral to ischemic limb
1. may benefit from adjunctive intraoperative fibrinolytics
2. if fails, bypass can be performed

19. Revascularization for ALI: Recommendations
• The usefulness of ultrasound-accelerated catheter-based
thrombolysis (delivery of thrombolytic agents) for patients with ALI
with a salvageable limb is unknown

20. Diagnostic Evaluation of the Cause of ALI:
Recommendations
• In the patient with ALI, a comprehensive history should be obtained to determine
the cause of thrombosis and/or embolization.
(Predisposing conditions: Atrial fibrillation, LV thrombus, aortic dissection, trauma, hypercoagulable
state, and limb artery bypass graft)
(History: MI, LV dysfunction  CCF, endocarditis, DVT with intracardiac shunt ( paradoxical artrial
embolism)

21. Diagnostic Evaluation of the Cause of ALI:
Recommendations
• In the patient with a history of ALI, testing for a cardiovascular cause of
thromboembolism can be useful
(most useful in patient without underlying PAD)
1. ECG: rhythm (Atrial fibrillation) or evidence of MI
2. Echocardiography: cardiac etiology – valvular vegetation, LALV thrombus, or intracardiac shunt

23. Available at surgicalpresentations