Peripheral Vascular Disease(1)

Peripheral Vascular Disease(1) Guo Xueli ( 郭学利 ) Dept. Vascular Surgery, First Affiliated Hospital

Arteries

Diseases of arteries may take one of three forms: occlusion dilatation arteritis #occluded by atheroma, thrombosis, embolism #dilatated due to degeneration of its wall #the seat of inflammation

Arterial occlusion Two types: partial or complete Causes: atherosclerosis (most often) embolism and trauma(common) The severity of the symptoms depends upon alternative route of blood flow (the form of collaterals)

Clinical features of arterial occlusion in the lower limbs A limb with an occluded artery is usually painful, pale, paralysed and pulseless. Pain: two forms intermittent claudication and rest pain

Intermittent claudication : Starts to walk there is no pain. After walked a few steps cramping pain appears. Claudication distance:the distance a patient can walk before pain comes on. This distance is inversely proportional to the severity of arterial occlusion. Short----the degree of occlusion is severe. Long---- the degree of occlusion is mild.

Rest pain is severe pain felt in the foot even at rest . Worse at night. Aggravated by elevating the foot. Relieved by lowering the foot.

Pallor Ischaemic limb---pale the limb is lowered--venous congestion---blue extravasation of blood from the capillaries ---bright red spots Paralysis Ischaemic limb are often paralysed and without sensation---bad sign

Pulselessness Main artery is occluded---arterial pulses are absent Good collaterals---the pulses are diminished in volume The places of pulsation: the radials, carotids , abdominal aorta, femorals popliteals, posterior tibial and dorsalis pedis arteries.

Temperature severely ischaemic feet --- cold Ulcers and gangrene Severe arterial insufficiency--- ulcers form The patch of skin becomes black and dry --- gangrene

Murmurs Narrow artery, blood flowing through it produces turbulence ---systolic murmur being audible A continuous machinery murmur ---intravenous fistula Location of atheromatous plaques atheromatous narrowing or occlusion sits: the bifurcation , iliac arteries, femoropopliteal segment, or the distal arteries.

Investigation Most patients suffering from pathological processes affecting the arteries tend to be elderly. Metabolic and age-related diseases--diabetes, hypertension, myocardial ischaemia and bronchitis should be excluded. Blood test: to detest abnormalities in the blood Plain x-rays: show up calcification in arteries. Blood flow: three basic parameters--pressure,volume and velocity

Pressure ankle:brachial index > 1.0---normal ankle:brachial index < 0.9---arterial disease Doppler sensor is used to measure the pressure Volume air-filled plethysmograph is used to measure the change Velocity Doppler blood flow detector

Transcutaneous oxygen tension measurement the oxygen tension is the best proof of adequacy of the oxygen delivery system. lower limb : around 55mm Hg---normal < 20mm---patient with rest pain and ischaemic ulcers

Ultrasound(B-mode) images provide information about the diameters of the various vessels at different levels and very valuable adjuncts of velocity measurements. Arteriography a radiopaque dye injected into an artery and x-ray taken to show the dye in the vessels and show up any stenosis,occlusion or dilatation. Digital subtraction angiography can enhance the outline of artery

Management of chronic arterial occlusion general advice:diabetes or hypertension should be kept under control meticulously. smoking---given up exercise---should be taken regularly diet: two types of lipoproteins--cholesterol and triglyceride the former---low cholesterol diet the latter ---weight reduction

medical treatment: aspirin---anti-adhesive effect analgesics---paracetamol or diclofenac vasodilators care of the feet: soft and comfortable socks toe-nails---be trimmed carefully

Buerger’s exercise can increase the circulation to the feet raise the limb---2 minutes lower it --- 2 minutes repeat the cycle---12 times daily for a few weeks

Sympathectomy Its effect is mainly on the vessels in the skin and subcutaneous tissues, may help some patients with rest pain. Surgical sympathectomy: 2 or 3 ganglia with the intervening trunk are removed. Chemical sympathectomy: the phenol solution is injected beside the bodies of the lumbar vertebrae by a long lumbar puncture needle.

Arterial surgery for occlusion in the lower limb Indications for operation: 1.Rest pain 2.Claudication 3.Ischaemic ulcers 4.Embolus: urgent embolectomy to save the limb.

Operations for disease at different sites Aorto-iliac artery stenosis 1.aortofemoral bypass: A synthetic arterial graft is anastomosed above to the aorta and below to the femoral artery. 2.iliac endarterectomy: the atheromatous plaques is removed and use a vein patch to suture the wound. 3.transluminal balloon angioplasty:inflation of the balloon to dilate the stenosed part.

Femoral and profunda artery stenosis The vessels above and below the block are normal. 1.femoro-popliteal bypass graft 2. Profundoplasty Arteries below the politeal a high rate of graft failure

Results of operation The reconstructive surgery of aorto-iliac disease---excellent Femoro-popliteal occlusion in the later stage ---compromised the success rate at the end of 5 years---50%

Acute arterial occlusion 1. represents an emergency. 2.irreversible ischaemic changes begin about 6 hours after the acute arterial occlusion. 3.may result either from trauma or embolism.

Occlusion due to trauma Blunt trauma to an artery: 1.the bruising may cause roughening of the intima--thrombosis occurs---occlusion. 2.the intima may become detached from the underlying muscle---sub-intimal haematoma---occlusion. During a long march the muscle in the unyielding anterior fascial compartment of the leg may be so swollen as to compress the anterior tibial artery--distal ischaemia and the crush syndrome ---urgent fasciotomy

Management to examine the palpation of the pulses. the pulses are absent and the limb is pale and cold---arterial occlusion. 1.the artery must be immediately exposed. 2.the affected part may be resected and an end-to-end anastomosis or a vein graft employed. 3. the artery is bruised---in spasm---4% lignocaine 4.to open the artery to deal with the thrombosis or subintimal haematoma---usually to resect the involved segment of the artery.

Embolic occlusion An embolus is a body which is foreign to the blood stream and which may get lodged in a vessel and cause occlusion. Emboli consist of the blood clot, air or fat. the blood clot---the most common The most frequent origin sites: 1.the roughened intima over necrosed cardiac muscle 2.the left atrium in a case of mitral stenosis 3.the cavity of a large aneurysm

Sites of lodgement of emboli Emboli can get lodged in any organ ---producing ischaemia of the part the most common sites---the lower limbs #cerebral embolism---hemiplegia #retinal arterial embolism---blindness #mesenteric artery---gangrene of the intestine #pulmonary artery---pulmonary embolism--death

Clinical features 1.the source of the emboli 2.severe pain ,cold with mottled blue and white patches 3.paralysis occurs within 4-6 hours after the onset of pain 4.lost the movement of the toes and touch sensation 5.the distal pulses are absent,the femoral pulse may be forceful

The embolic cause include cardiac arrhythmia myocardial ischaemia valvular disease atherosclerosis

Treatment 1.An infusion of 5,000-10,000 units of heparin to prevent thrombosis. 2.Severe ischaemic pain requires with analgesics . 3.Urgent embolectomy. 4.Anticoagulant therapy is continued postoperatively.

Air embolism Air embolism---right-sided heart failure 1.sucked into an open vein 2.reach the venous system after insufflation into the fallopian tube, or during illegal abortion 3.rigid bottles with air vents were used for intravenous infusion The collapsible bottles in use nowadays

Treatment 1.the Trendelenberg position(the head side is low) and turned onto his left side. 2.aspirate the air from the right ventricle by needle. 3.to expose the heart for aspiration under direct vision.

Fat embolism syndrome Cause: extensive and multiple fractures Fat droplets---platelet aggregation---consumption coagulopathy Fat droplets---fatty acid---acute lung injury clinical feature: dyspnoea, skin petechiae, hypoxaemia, thrombocytopenia, falling haemoglobin and fat globules in the urine. Symptoms arise 2 or 3 days after injury.

Two types Cerebral type:drowsy, restless, disoriented, and later comatose. Pulmonary type:increasing cyanosis with signs of right heart failure. Treatment :vasopressors, inotropes and mechanical ventilation. high-dose corticosteroids, low molecular weight dextran.

Gangrene Gangrene:death with putrefaction of macroscopic portion of tissue. Necrosis:the death of individual cells or groups of cells. Sequestrum: a dead piece of bone. Slough: a piece of dead soft tissue e.g. fascia, tendon or skin.

The classic presentation of gangrene---the distal part of a limb. Certain viscera may be affected by gangrene, the appendix, small intestine, and gallbladder. Causes 1.ischaemia: i.atherosclerosis ii.embolism iii.diabetes iv.thromboangiitis obliterans(Buerger’s disease)

v. Raynaud’s disease and ergotism vi.inadvertent intra-arterial injection of drug, thiopentone and cytotoxic drugs. 2.infections 3.trauma: i.direct trauma ii.indirect trauma 4.physical agents: burns due to heat, boiling liquids, chemicals, electricity and irradiation.

Clinical appearance The gangrenous part: 1.cold and motionless 2.arterial pulsation, capillary response---absent 3.the colour changes at first---pallor later---dusky grey or purple discoloration (the pooling of blood in the part) finally---greenish or brownish black (the disintegration of haemoglobin and formation of iron sulphide)

Types dry gangrene: occluded gradually, the part is dry, wrinkled, and black. No foul smell. moist gangrene: occluded suddenly, putrefaction of the tissue, anaerobic infection. Foul smell. moist gangrene is seen in the following conditions: 1. occluded suddenly by a ligature or embolus 2.venous obstruction along with arterial occlusion 3.infection in diabetic tissues 4.in an internal organ, e.g. in acute appendicitis and strangulated bowel

infection by gas-producing organisms---crepitus be felt on palpation Nature history untreated gangrene---circumscribed or spread in extent the line of demarcation between the gangrenous and healthy In dry gangrene: the line of demarcation ---a few days separation---with the minimum infection the bone gangrene separation takes longer time

In moist gangrene: favourable for the growth of bacteria the line of demarcation at a high level---more of the limb lost convert moist gangrene into the dry type Spread of gangrene: the moist type---spread upwards black patches of skin at higher level than the gangrenous part infection---spread upwards

a local amputation---the risk of leaving gangrenous tissues behind to avoid this possibility---an above-knee amputation Treatment :as far as possible try to save the limb 1.to improve the blood supply--direct arterial surgery and interruption of the sympathetic nerve supply 2.good blood supply---a conservative excision 3.gas gangrene or rapidly spreading gangrene--amputation to save his life

General treatment : in embolic gangrene---to treat cardiac failure, atrial fibrillation and anaemia diabetes--- be controlled pain --- non-narcotic drugs Local treatment: #limb ---exposed to encourage dryness, and cool to reduce the metabolic rate and the need of the oxygen #protect the pressure areas #release underlying pus

Special varieties of gangrene Diabetic gangrene three factors---the development of diabetic gangrene 1.the peripheral neuritis of diabetes---trophic changes 2.atheroma of the arteries---ischaemia 3.an excess of sugar---lowers their resistance to infection

the neuropathy---a harmful effect in two ways 1.impaired sensation---neglect of minor injuries 2.the muscular involvement---deformities in the foot---the pressure on the metatarsal heads--callosities So that the infection can rapidly spread upwards. Major arterial disease is usually absent. the dorsalis pedis and posterior tibial pulses ---palpable no intermittent claudication and pain

to examine any pus to test the blood and urine for detecting the presence and severity of diabetes Treatment 1.be brought under control by diet and drug 2.gangrene is managed along the usual lines 3.free drainage of the area with removal of sloughs

Traumatic gangrene direct traumatic gangrene bedsore---most common ulcers---result from the pressure of splints or plasters bedsores ---in a bedridden patient, specially who has suffered injury or disease of the spinal cord. the factors in the development of bedsores: #pressure #loss of the trophic influence of nerves two important factors

#anaemic or malnourished of nerves #moisture---increase the rate of extension the most common sites: the sacrum, the greater trochanter and the heels the prevention of bedsores: 1.a foam mattress 2.the bedsheets must be kept free of all wrinkles 3. sweat, urine or faeces not be allowed to collect over the skin 4.the posture must be changed two-hourly 5.a mattress with a honeycomb of cavities

the treatment is difficult hence the very great importance of prevention Treatment 1.the preventable measures must be continued 2.pent up pus---evacuation 3.small sloughs---Eusol solution large sloughs---surgical removal 4.oedmatous granulation---magnesium sulphate glycerine paste 5.shifting a skin flap to cover the raw area

Indirect traumatic gangrene due to occlusion of an artery 1.pressure, e.g.from a broken bone in a fracture 2.thrombosis, e.g. following injury 3.ligation of a main artery the collateral circulation is adequate---no gangrene Treatment #to deal with the causes #dry gangrene---amputation above the line of demarcation #moist gangrene---amputation to save the life

Frostbite due to exposure to cold the vessel---oedema, blistering, finally gangrene Treatment #warmed gradually to body temperature #wrapped in cotton wool #warm drinks, analgesics or paravertebral injection of the sympathetic chain

Amputations indications : 1.dead i.e.gangrene is present i.major vessels, e.g. from atherosclerosis or embolism ii.peripheral vessels,e.g. in diabetes, Buerger’s disease, Raynaud’s disease,etc. 2.dangerous. Moist gangrene and gas gangrene. the danger to life arises from the absorption of the potent toxins of the clostridia or other anaerobic bacteria.

3. A total loss i. multiple severe lacerations and fracture due to a bomb-blast injury or a road accident. ii. severe contractures or paralysis make the limb impossible to use, and interfere rather than help with locomotion. iii. severe rest pain make life miserable, amputation improves the quality of life.

Amputation at different levels Minor(distal) amputations a finger or toe injury, a small vessel disease (diabetes or Buerger’disease), where gangrene of the toes occurs but the blood supply to the surrounding tissues is good. in diabetes---excision of a metatarsal bone in Buerger’disease--- trans-metatarsal amputations a long plantar flap---the suture line is on the dorsal side, away from the weight-bearing area.

Major amputation above-knee and below-knee amputations. above-knee amputations---abundant blood supply to an absolute guarantee of sound healing of the stump; the function of the artificial limb is not good. below-knee amputations---a lesser certainty of sound healing of the stump; the function of the artificial limb is good.

In the past: Twice as above-knee amputations were performed as below-knee During recent years: the ratio has been reversed, partly because arterial surgery is available to improve the blood supply to the limb.

Flaps muscles which have a rich blood supply---be raised as a part of the flap to cover the bony stump--- sound healing of the wound above-knee amputations---equal anterior and posterior flaps. below-knee amputations---a single long posterior flap

through-knee amputations a long anterior flap, the patellar tendon is sutured to the hamstrings so that both the rectus femoris and the hamstrings help in stabilizing the hip joint in the erect posture. Symes amputations The lower ends of the tibia and fibula are sawn across just above the line of the ankle joint. a posterior flap consisting of the skin of the heel with its underling pad of fibrofatty tissue.

Points in technique the main artery and vein individually ligated---to avoid the arteriovenous fistula. the nerves---gently drawn down cut with a sharp knife allowed to retract upward so that the stump neuroma which inevitably forms should be away from pressure.

the bone---cut with a saw and any splinter removed absolute haemostasis is ensured. suction drains to prevent the collection of serum or blood. the muscles---stitched together over the bone incorporate the deep fascia

Postoperative care of an amputations #.a gauze and cotton wool dressing #.a demoralizing operation, with a inflatable prosthesis a lower limb amputee can get on his feet the day after the operation.

#.exercise: in the past---an important part of rehabilitation and prepared the stump for the prosthesis nowadays--- prosthesis mobilization automatically provides exercises for the stump muscles, preventing the development of disuse atrophy and contractures.

Complications #reactionary haemorrhage, haematoma formation, infection, sequestrum formation, wound dehiscence and gangrene of the flaps. at a later stage---an adherent scar # phantom limb