Lower Limb Ischemia PDF

Lower limb ischemia Dr. Abdulwahab A AL-Makhathi  Lower limb ischemia Anatomy of lower limb artery  Lower limb ischemia Anatomy of lower limb artery  Lower limb ischemia Anatomy of lower limb artery  Lower limb ischemia DEFINITION : Impairment arterial blood su...

Lower limb ischemia Dr. Abdulwahab A AL-Makhathi  Lower limb ischemia Anatomy of lower limb artery  Lower limb ischemia Anatomy of lower limb artery  Lower limb ischemia Anatomy of lower limb artery  Lower limb ischemia DEFINITION : Impairment arterial blood supply sufficient to interfere with nutrition and functions of the limb. TYPES Acute ischemia. Chronic ischemia.  Acute limb ischemia Embolism " the commonest cause " Cardiac origin (85-90%) Atrial fibrillation is the most common source. Ventricular thrombus (post MI) Debris from damaged valves (RHD or endocarditis) Noncardiac origin (10-15) Atherosclerotic plaque debris Thrombus from aneurism  Acute limb ischemia Embolism Site of impaction 1) The bifurcation of the common femoral artery (40%). 2) The aortic bifurcation. 3) The bifurcation of the popliteal a. 4) The bifurcation of the brachial a. 5) The bifurcation of the common carotic a.  Acute limb ischemia Atherosclerosis DEFINITION: Degenerative arterial disease due to aging process affecting the whole arterial system. INCIDENCE: Age : > 45 years. Sex : male > female Risk factors : Hypertension , obesity , hypercholesterolemia , +ve family history , hyper triglycerides , heavy smokers  Acute limb ischemia PATHOLOGY : a. Sudden occlusion of an artery stagnation of the nearby vein tissues will be loaded with fluid. - If gangrene occur, it will be moist aseptic. b. Different tissues tolerate ischemia to variable extent : - Muscle : irreversible damage within 6 - 8 hours. - Skin : moist aseptic gangrene within 24 hours. Acute limb ischemia Acute limb ischemia  Acute limb ischemia CLINICAL PICTURE : [ 6PS ] 1) Pain :  sudden onset.  bursting or burning ( nerve ischemia ) 2) Pallor : which is replaced later on by mottled cyanosis due to accumulation of deoxygenated blood then finally black ( if irreversible damage ). 3) Pulselessness : below the level of occlusion. 4) Parasthesia :reflects neural ischemia 5) Paralysis : due to muscle ischemia. 6) Progressive coldness (poikilothermia): decreased energy production due to cellular hypoxia.  Acute limb ischemia CLINICAL PICTURE : [ 6PS ]  Acute limb ischemia INVESTIGATIONS: (A)ECG & Echocardiography for evidence of valvular heart disease. (B)Doppler U/S & duplex scanning to detect the level of obstruction. (C) Arteriography : but may cause a delay for 2-3 hours, therefore it's not done in a threatened limb. (D)Laboratory studies : Acidosis & CK indicate extensive muscle necrosis.  Acute limb ischemia Treatment Preoperative treatment Immediate heparin start with 5000 – 10000 IU then 5000 IU every 2 hours to prevent propagation of thrombosis unless contraindication (HIT). The fluid rehydration to protect the kidneys from myoglobinuria. Avoid elevation of limb to maximize arterial flow. Foley catheter inserted to monitor urine output.  Acute limb ischemia A. Urgent Embolectomy Anaesthesia : better under local anesthesia ( may be spinal anesthesia ). Operation :  Preferably percutaneous via Fogarty balloon catheter but may be done open if necessary.  It must be within 6 - 8 hours to save the limb. but if done after that time it will be called delayed embolectomy  The value of delayed embolectomy is lowering the level of amputation because of irreversible muscle damage which has occurred.  Acute limb ischemia Treatment  Acute limb ischemia Urgent Embolectomy  Acute limb ischemia Treatment B. Bypass Graft Thrombectomy: Bypass thrombectomy is more likely to succeed with prosthetic bypasses. The performance of a fasciotomy to circumvent reperfusion injury/compartment syndrome is an important consideration. C. Amputation If established gangrene.  chronic limb ischemia DEFINITION: Slowly progressive arterial obstruction that gives enough time for collaterals to develop and, therefore gangrene does not occur rapidly. AETIOLOGY: [A] Above 45 years : Atherosclerosis is the commonest cause. [B] Below 45 years : In non diabetics : - In Males : Buerger's disease ( thrombangitis oblitrante ) - In Females : Raynaud's disease In diabetics : Diabetic foot & gangrene.  chronic limb ischemia CLINICAL Presentation : Asymptomatic (50%) Pain (Claudication). Pallor. Paraesthesia. Cold limb. Diminished or absent arterial pulsation. Skin trophic ulcer. gangrene.  chronic limb ischemia CLINICAL Presentation : pain Pain.  chronic limb ischemia CLINICAL Presentation : Pain.  chronic limb ischemia CLINICAL Presentation :  chronic limb ischemia CLINICAL Presentation : chronic limb ischemia chronic limb ischemia ABI  chronic limb ischemia INVESTIGATIONS: (A) Laboratory studies: CBC , RBG , UREA , CREATIN and serum lipid (B) Ankle-brachial index (C) Doppler U/S & duplex scanning to detect the level of obstruction. (D)DIGITAL SUBTRACTION ANGIOGRAPHY (E) COMPUTED TOMOGRAPHIC ANGIOGRAPHY : It is done only if direct arterial surgery is considered. (F) MAGNETIC RESONANCE ANGIOGRAPHY [ M.R.A ] It can visualize arteries without injection of any contrast  chronic limb ischemia DIGITAL SUBTRACTION ANGIOGRAPHY [ D.S.A ] Less Invasive. X-ray picture is taken & the image is introduced to the computer. The dye is injected I.V to reach the heart then to the arteries. Further X-ray picture is taken & the image is introduced to the computer. By subtracting the 1st image from the 2nd an arteriogram can be obtained. chronic limb ischemia  chronic limb ischemia COMPUTED TOMOGRAPHIC ANGIOGRAPHY Values : shows of the vessel wall. Site & length of obstruction. Collateral circulation. Distal Run off i.e. distal flow beyond the occlusion. Methods : Direct trans-femoral arteriography. Direct trans-lumbar aortography. Ante-grade trans-brachial aortography. Retro-grade trans-femoral aortography.  chronic limb ischemia INVESTIGATIONS: Trans-lumbar Aortography complete occlusion of Lt.iliac artery occluded Rt. external iliac artery  chronic limb ischemia Trans-femoral Arteriography chronic limb ischemia  chronic limb ischemia (1)Conservative treatment INDICATIONS: Mild Ischemia ( No Rest pain & distal Run off ) METHODS 1)Relief of symptoms i) Improve general health & tissue oxygenation : correction of anaemia & any associated lesion e.g. heart lesion. ii) Protection of ischemic parts : carefully wash, dry & powder ischemic parts with use of suitable shoes. iii) Improve blood supply : V.D. drugs as Trental & Anti-platelets as Aspirin (small dose) B. Progression of the disease 1. Stop smoking. 2. Control of D.M, hypertension ….etc  chronic limb ischemia (2)Endovascular surgery INDICATIONS 1) Suitable only for localized occlusion in a large & medium sized vessels. 2) Suitable for unfit patient for surgery. METHODS 1. Percutaneous trans-luminal balloon angioplasty (PTA) A special balloon catheter is introduced at site of narrowing of the blood vessel. The balloon is inflated to dilate the stenosed segment. 2. Arterial stent (After balloon dilatation) A stent is introduced to keep the lumen patent. 3. Laser angioplasty Destruction of the atheromatous plaque by laser.  chronic limb ischemia (3)Surgical procedures 1) ARTERIAL RECONSTRUCTION A) Thrombo-end-arterectomy Indications : 1) Rest pain + distal Run off 2) localized obstruction. 3) large Arteries. Technique :  Arteriotomy then removal of thrombus & thickened atherosclerotic intima leaving a patent lumen.  Before closing, the distal intima should be attached to arterial wall by interrupted sutures to prevent it's dissection later on.  After closing, the patent lumen will be endothelialized. chronic limb ischemia  chronic limb ischemia B) Arterial by-pass Indications : 1) Rest pain + distal Run off 2) multiple lesions. 3)large & medium sized arteries. Technique : The idea is to by-pass the obstruction by inserting a graft from the health artery above the obstruction to distal run off below chronic limb ischemia  chronic limb ischemia Types of grafts : 1)Synthetic grafts e.g. Aorta-iliac graft They may be : (a) Teflon or Dacron. (b) Polytetra Flouroethylene (PTFE). 2. Natural grafts e.g. Femoro-popliteal graft They may be : (a) reversed long saphenous vein reversed to avoid obstruction by its valves (b) In situ long saphenous vein valves are destroyed by a stripper chronic limb ischemia chronic limb ischemia  chronic limb ischemia 2)INDIRECT ARTERIAL SURGERY (Sympathectomy) Indications i) Vascular conditions. 1)Rest pain + No Run off ( Buerger’s or Raynaud’s disease ) 2) After amputation to help wound healing. ii) Hyperhidrosis Excessive sweating of the hands Contraindications : 1)Intermittent claudications 2)Established.  chronic limb ischemia Principles of lumbar sympathectomy 1) Fit : ( surgical sympathectomy ) - Preganglionic section of L1 ,L2 & L3 ganglia. 2) Unfit : ( chemical sympathectomy ) Para-vertebral block of L1 , L2 & L3 ganglia. 5% phenol in water is injected beside bodies of L1,2&3 ganglia under screen to destroy these ganglia. N.B : The 1st. lumbar ganglion should be preserved on one side, otherwise failure of ejaculation occurs  chronic limb ischemia 3) AMPUTATION [ I ] Conservative amputation Indications : 1) If good blood supply to adjacent gangrenous tissues. 2) If line of separation & demarcation are well defined. Technique : 1) Excision at line of demarcation. 2) The skin should be neither redundant nor undertension. [ II ] Urgent high amputation Indications : 1) If spreading gangrene. 2) If uncontrolled infection & toxaemia.  chronic limb ischemia Technique : 2) Above knee amputation (A.K.A) The stump will be supplied by the profunda femoris. 2) Below knee amputation (B.K.A) If popliteal pulse is felt. chronic limb ischemia Conservative Amputation