Acute limb ischemia.pdf

Acute limb ischemia Bayan Albaqami Kholoud AlHamdan Table of contents Definition and etiology 01 04 Treatment options Approach to assessment 02 05 Compartment syndrome 03 06 Reperfusion syndrome Diagnosis 01 Definition and Etiology Definition Acute limb ischemia is a vascular emergency in which the art...

Acute limb ischemia Bayan Albaqami Kholoud AlHamdan Table of contents Definition and etiology 01 04 Treatment options Approach to assessment 02 05 Compartment syndrome 03 06 Reperfusion syndrome Diagnosis 01 Definition and Etiology Definition Acute limb ischemia is a vascular emergency in which the arterial blood supply to the limbs is suddenly reduced/occluded Ischaemia beyond 6 hours is usually irreversible and results in limb loss. Upper or lower limbs can be affected, but lower limbs are more common Bailey & Love’s Short Practice of Surgery 27 th edition Etiology Thrombosis Native arterial thrombosis Peripheral arterial disease Stent or graft thrombosis Aneurysmal thrombosis Thrombophilia Arterial vasoconstriction Vasoactive drugs Raynaud’s phenomenon Shock https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H518287604 Embolism Cardiac emboli (A- fib, mi) Cholesterol emboli Trauma Direct arterial injury Traumatic arterial dissection with subsequent thrombosis or thromboembolism Acute vs chronic Acute limb ischemia ○ ○ Chronic limb ischemia ○ Patient with normal underlying vasculature, experience acute arterial occlusion Signs develop rapidly in less than 2 weeks Patient with longstanding symptoms of peripheral artery disease for longer than 2 weeks Acute-on-chronic limb ischemia ○ In patients with known peripheral artery occlusive disease or those who have undergone prior revascularization will present with suddenly increasing symptoms of arterial occlusion https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H518287604 https://www.uptodate.com/contents/classification-of-acute-and-chronic-lower-extremity-ischemia?search=classification%20of%20acute%20abd%20chronic%20limb%20ischemia&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1 CLINICAL PRESENTATIONS OF ALI The clinical presentation of acute arterial occlusion depends upon the time course of vessel occlusion; the location of the affected vessels, ranging from proximal large vessel occlusion resulting in ischemia of the entire extremity to distal small vessel occlusion resulting in digital ischemia; The 6 Ps: Pain: Sudden & Severe and is most severe in the distal aspects of the ischemic limb. Pallor: then becomes mottled and purple-blue. Pulselessness Poikilothermia: cold to touch Paresthesia: progresses to anesthesia. Paralysis: Initial muscle weakness progresses to profound irreversible paralysis https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H518287604 02 Approach to assessment History History of presenting illness Associated symptoms History of PVD History of prior revascularization History of blood disorders History of chronic ischemia prior to the acute event PHYSICAL EXAMINATION A careful examination of both lower extremities is necessary to detect signs of ischemia. Pain: usually located distally in the extremity, gradually increases in severity, and progresses proximally with increased duration of ischemia. Later, the pain may decrease in severity Skin perfusion: for temperature, color, and capillary refill. The skin of the ischemic extremity is typically cool (Poikilothermic) and Pale or mottled with delayed capillary filling. Pulses : Acute limb ischemia typically manifests with severely reduced pulses ○ should include palpation of all pulses, including the femoral, popliteal, dorsalis pedis, and posterior tibial pulses as well as the upper extremity pulses (ie, subclavian, axillary, brachial, radial, and ulnar) Neurologic examination: sensory deficits such as numbness or Paresthesias. Major loss of sensory or motor function (Paralysis). https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H518287604 Rutherford’s classification https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H518287604 Rutherford’s classification These categories (viable, threatened, nonviable ) are useful for helping guide decisions about additional vascular imaging and management. Viable limbs: no immediate threat of tissue loss. There is no sensory loss or muscle weakness, and both arterial and venous Doppler signals are audible. Marginally threatened limbs: There is minimal pain (in the toes), no/minimal sensory loss, no muscle weakness, arterial Doppler signals inaudible, and venous Doppler signals are audible. there is usually sufficient time for vascular imaging to define the extent of disease. Immediately threatened limb: need Immediately revascularization, Sensory loss involves more than the toes and may be associated with rest pain. There is mild-to-moderate muscle weakness, arterial Doppler signals inaudible, and venous Doppler signals are audible. Nonviable limb: Complete motor & sensory deficits, arterial and venous Doppler signals are inaudible. https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H518287604 Diagnosis The diagnosis of acute limb ischemia can generally be made based upon the history and physical examination, including assessment of the ankle-brachial index bilaterally. The suspected cause and severity of ischemia determines whether or not to proceed with additional diagnostic testing https://www.uptodate.com/contents/embolism-to-the-lower-extremities?search=embolism%20to%20the%20lower%20extremities&source=s earch_result&selectedTitle=1~150&usage_type=default&display_rank=1 https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H518287604 Vascular imaging The best intial test: Arterial and venous Doppler The Confirmatory tests: Angiography (DSA, CTA, MRA) Confirmatory test should only be performed if they do not result in treatment delays. The modality of choice is Digital subtraction arteriography (DSA) Patients with viable or marginally threatened limbs are usually candidates for urgent vascular imaging However, patients with an immediately threatened extremity and nonviable limb should undergo further evaluation and treatment in a surgical suite. https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H518287604 Digital-subtraction angiogram of the right lower limb. Figure A displays the occlusion of the right popliteal artery (red arrow). Figure B demonstrates the result after the stent implantation Questions 1) Which stage of Rutherford’s classification has inaudible venous Doppler signals ? A) Stage I B) Stage IIa C) Stage IIb D) Stage III 2) What is the best initial imaging modality to diagnose ALI Reference Bailey & Love’s Short Practice of Surgery 27 th edition https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-isch emia#H518287604 https://www.uptodate.com/contents/embolism-to-the-lower-extremities?search=embolism%20to %20the%20lower%20extremities&source=search_result&selectedTitle=1~150&usage_type=default& display_rank=1 https://www.uptodate.com/contents/classification-of-acute-and-chronic-lower-extremity-ischemia ?search=classification%20of%20acute%20abd%20chronic%20limb%20ischemia&source=search_res ult&selectedTitle=1~150&usage_type=default&display_rank=1 04 ALI Management Kholoud AlHamdan Initial management Acute limb ischaemia is a surgical emergency. Complete arterial occlusion will lead to irreversible tissue damage within 6 hours. High-flow oxygen Adequate IV access Analgesics A therapeutic dose heparin or preferably a bolus dose then heparin infusion should be initiated as soon as is practical. Conservative management Rutherford 1 and 2a; a prolonged course of heparin may be the most effective non-operative management of acute limb ischaemia. Regular assessment (to determine its effectiveness) through monitoring APPT and clinical review. Surgical interventions may be warranted if no significant improvement is seen. Interventional management Endovascular: Percutaneous transluminal angioplasty Catheter directed thrombolysis (CDT) Surgical (open): Embolectomy Endarterectomy Bypass Interventional management Endovascular: Catheter directed thrombolysis (CDT) By Urokinase and rtPA (recombinant tissue plasminogen activator) Percutaneous transluminal angioplasty Interventional management Surgical (open): Embolectomy by fogarty catheter. Endarterectomy Bypass https://youtu.be/2WK4Mt__CYs Interventional management Surgical (open): Embolectomy by fogarty catheter. Endarterectomy Bypass https://youtu.be/YnsofXmPpH8 Interventional management Surgical (open): Embolectomy by fogarty catheter. Endarterectomy Bypass So how to choose the intervention modality ? If the cause is due to thrombotic disease: Local intra-arterial thrombolysis Angioplasty Bypass surgery If the cause is embolic: Embolectomy via a Fogarty catheter Local intra-arterial thrombolysis Bypass surgery (if there is insufficient flow back) Surgery strategy is made based on : Site of embolus/thrombus. Duration and Severity since injury. The expertise and facilities of the treating team. Co-morbidities. 05 Complications Kholoud AlHamdan Reperfusion injury, a condition characterized by endothelial damage caused by a returning blood supply after a period of ischemia. This sudden increase in capillary permeability can result in: Compartment syndrome Release of substances from the damaged muscle cells, such as: K+ ions causing hyperkalaemia H+ ions causing acidosis Myoglobin, resulting in significant AKI Compartment syndrome (CS) The tissue swelling as a result of reperfusion injury raises pressure in the limb muscles which are constrained by fascial compartments. ⇒ Reduce perfusion of already damaged tissues ⇒ extremity becomes ischaemic again, and the limb may be lost, despite previously successful revascularization. Tx: Fasciotomy Q1) What Rutherford stage requires amputation? A) I B) IIb C) III Q2) What is the drug of choice for the initial management of ALI ? A) Warfarin B) Heparin C) Aspirin Any Q? Thank you References European Society for Vascular Surgery (ESVS) 2020 Clinical Practice Guidelines on the Management of Acute Limb Ischaemia Acute limb ischaemia - clinical features - management. TeachMeSurgery. Retrieved October 2, 2022, from https://teachmesurgery.com/vascular/peripheral/acute-ischaemia/ 2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: Executive Summary