Veins have thinner walls, less muscle and elastic tissue, and lie closer to the skin surface than do arteries. Veins also differ in that some, mostly in the limbs and especially the lower limbs, have endothelial valves. These permit blood flow only towards the heart, preventing reflux. The return of blood to the heart is therefore reliant on three factors: patency of the veins, valve competence and contracting surrounding muscles (muscle pump). During exercise, the veins in the leg are compressed by the contracted leg muscles, which act as a ‘muscle pump’, so allowing blood to be returned towards the heart. Blood is returned from the lower limbs to the right side of the heart via the inferior vena cava by the pumping action of the muscles. This pumping action from the calf and foot muscles compresses the deep veins of the legs, which contain one-way valves, and pushes the blood back to the heart, with backflow being prevented by the valves. These muscular contractions allow emptying of the blood from the superficial veins into the deep veins, via the communicating vessels. The venous system of the leg comprises a superficial system in the skin and subcutaneous fat, and a deep system beneath the fascia. The main superficial leg veins are the long and short saphenous, which form a venous network with other perforating veins, which pass through the fascia to join the deep veins. These deep veins run alongside the arteries and have the same names.

Symptomatic PAOD is commoner in men and also occurs earlier, the incidence being twice as high as than women <60 in men under 60 years old (Kannel et al, 1970). Female sex hormones are thought to account for this difference, as symptomatic disease is more common postmenopause (Sans et al, 1997).

It is considered proven that smoking is the most preventable cause of cardiovascular morbidity and mortality. Nicotine and carbon monoxide have been shown to produce endothelial injury, leading to the development of atherosclerotic plaque in the arteries (Powell, 1991). Quitting smoking will reduce the risk of developing PAOD (Bowlin et al, 1994), and studies have shown evidence of reduction in disease progression within 3 months (Seltzer, 1989). Smoking also enhances the effect of other risk factors such as hypertension and hyperlipidaemia (Pasternak et al, 1996). Smoking should be stopped and patients informed of the harmful effects of nicotine on their condition. The majority of smokers with PAOD are nicotine addicts and require counselling and behavioural support therapy. In addition, nicotine replacement therapy, bupropion or varenicline tartrate can help relieve cravings and withdrawal symptoms in order to successfully quit.

Hyperlipidaemia and hypercholesterolaemia are recognized risk factors for atherosclerosis. A high dietary intake of saturated fat is known to contribute to a high blood cholesterol, and hyperlipidaemia is known to have a congenital factor (Oliver, 1991). In addition to a healthy low-fat diet, lipid-lowering therapy (statins) improves endothelial function. Irrespective of cholesterol levels, the Heart Protection Study strongly recommends that all patients with PAOD should be treated with a statin to reduce vascular mortality (Collins, 2002). Weight reduction will also benefit obese patients with intermittent claudication, as this reduces the workload on the lower limbs.

Peripheral arterial occlusive disease is a major complication of both insulin-dependent and non-insulin-dependent diabetes mellitus (Beach et al, 1988). Diabetics are more susceptible to atherosclerosis due to calcification of the medial lining of the arteries (Edmonds and Foster, 2005). Neuropathy is also common, which causes a lack of sensation, making the diabetic prone to trauma, resulting in foot injuries, infections and non-healing ulcers. Diabetic leg ulcers are usually situated on the bony prominences of the feet, resulting in necrotic wounds. Good blood glucose control reduces the risk of small vessel limb disease.

Foot care advice should be given to all patients with arterial occlusive disease, not only diabetics, to help reduce the incidence of injury, and followed up with an information leaflet to aid concordance (Ley, 1993). The nurse can help educate the patient by teaching them how to perform self-assessment and foot care (Fig. 22.2). Patients should be instructed to check their feet daily or, if they are unable to do this for themselves, a relative or carer will need to be taught how to do this. The importance of contacting their nurse, doctor, foot clinic/podiatrist immediately if problems occur should be stressed.

Hypertension has been associated as a risk factor with generalized vascular diseases as well as peripheral occlusive disease (Kannel and McGee, 1985). Increased mechanical stress due to higher blood pressure can result in endothelial damage to the artery wall. Screening, advice and treatment to maintain blood pressure below 140/90 mmHg is recommended by the British Hypertension Society (Williams et al, 2004). Blood pressure should be taken in both arms on initial assessment. If a higher value is noted of between 10 and 15 mmHg, this may indicate an arterial stenosis on the side of the lower reading.

Homocysteine is a by-product of protein metabolism, and elevated levels are linked to acceleration of atherosclerosis and increase the risk of thrombosis (Boushey et al, 1995). Elevated homocysteine levels should be checked, particularly in patients under 60 years old. Daily supplements of folic acid may help reduce the risk of developing atherosclerotic vascular disease (Hankey and Elkeboom, 1999).

Binge drinking should be avoided and drinking kept within recommended safe limits: 3–4 units daily for men and 2–3 units daily for women.

Physical inactivity is a major risk factor for cardiovascular disease. Regular exercise combined with weight reduction is associated with lowering cholesterol and blood pressure.

Abdominal obesity in combination with hypertension, dyslipidaemia and glucose intolerance will result in metabolic syndrome. This increases the risk of type 2 diabetes and vascular disease (Grundy et al, 2004).

Social deprivation also increases risk factors for developing peripheral arterial disease, as patients from lower social classes are more likely to eat an unhealthy diet, exercise less and smoke. Unemployment and high anxiety levels have been found to contribute to development of the disease (Bowlin et al, 1994).

Vascular diseases are generally caused by a combination of risk factors. For reasons unknown, men are more prone than women to all forms of vascular disease, especially aortic aneurysms. However, women’ss protection diminishes with age. Over the age of 70 years old, the risks are similar for both sexes (Kannel and McGee, 1985).

Intermittent claudication is pain only induced by exercise, experienced in the foot, calf, thigh or buttock, depending on the level of arterial occlusion, when a certain distance is walked. The pain is caused by inadequate blood supply to the muscles and can vary in severity and walking distance. Walking at a brisk pace or on an incline will produce symptoms earlier. Patients frequently refer to their symptoms as an ache, heaviness or dullness of the leg muscles. Intermittent claudication may affect one or both legs, is more common in the calf and is always relieved by rest.

Patients with intermittent claudication may not experience a major handicap to their lifestyle, or their symptoms may even resolve with regular walking exercise. McAllister (1976) found that a patient with intermittent claudication had a 50% chance of symptoms spontaneously improving, a 30% chance of remaining unchanged, with 20% of patients deteriorating. Although some claudicants may initially fear limb loss, only 7 of 100 patients (6 of whom had diabetes) underwent major amputation. If the condition becomes more severe, it may lead to signs of critical ischaemia such as rest pain, ulcers and possible gangrene. In the 1950s, Fontaine classified the signs and symptoms of chronic leg ischaemia into four stages (Box 22.1). It is therefore important that patients with intermittent claudication modify their risk factors at an early stage to help prevent disease progression and also to reduce their chance of suffering a heart attack or stroke.

Rest pain is a chronic pain described as ‘associated with a chronic pathological process which causes continuous pain’ (Bonica 1990, cited in Twycross, 1994:17). As the disease progresses, the blood flow to the leg is reduced such that pain occurs while resting rather than induced by exercise. Patients with ischaemic rest pain initially awake at night with pain in the foot and toes. Pain is continually present when the patient is immobile and prevents sleep occurring, causing rapid deterioration in the patient’s morale. Temporary relief may be gained by hanging the limb out of bed or by sleeping in an armchair with the foot down.

Arterial disease may ultimately result in tissue loss of the toes, foot or leg. Critical leg ischaemia is a condition which endangers the distal part of the limb, and there is a high risk that the patient will require toe or limb amputation. The symptoms and signs specified in the Second European Consensus Document on Critical Leg Ischaemia (European Working Group, 1991) are:

Limb pulses are palpated to assess the adequacy and volume of the blood supply at femoral, popliteal, posterior tibial and pedal pulse sites (Fig. 22.4). The absence of pulses or a weak pulse may determine the presence of arterial disease, and require confirmation by Doppler ultrasound (Moffatt et al, 1994).

The presence of bruits (abnormal ‘whooshing’ sounds or murmurs) may be heard with a stethoscope. This turbulent flow, heard over major arteries, may be significant in carotid vessels which are narrowed due to atherosclerosis.

Doppler ultrasound is a practical non-invasive test using ultrasonic high-frequency sounds emitted from a hand-held transducer probe. It is used to assess the arterial blood supply to the lower limb by listening to the arterial sounds, and for measuring the ankle/brachial systolic pressure ratio, to aid diagnosis and detect the degree of arterial insufficiency. Doppler ultrasound can also be used to ascertain the presence of pedal pulses following intervention such as angioplasty, thrombolysis or reconstructive bypass surgery.

The highest systolic pressure in the arm at the brachial artery is compared with the highest systolic pressure in the ankle at the dorsalis pedis and the posterior tibial artery, to give an ankle–brachial pressure index (ABPI):

The lower the ABPI, the greater the arterial impairment. However, false high readings may be obtained in patients with diabetes, atherosclerosis, and chronic renal disease, as a result of calcification of the arteries, which means the sphygmomanometer cuff cannot fully compress the hardened arteries.

ABPI is also known to be a predictor of survival in vascular patients; the lower the ABPI, the higher the risk of vascular mortality (McDermott et al, 1994).

Measurement of toe pressures can be performed to assess arterial blood flow in diabetics by using photoplethysmography (PPG). A special small occlusion cuff is usually attached to the first toe, and the PPG sensor uses changes in infrared light to detect blood flow. This technique is feasible because distal pedal vessels in diabetics are less calcified and incompressible than ankle vessels.

Angiography is usually performed under a local anaesthetic and can be undertaken on a day case basis, depending on the age, social circumstances and clinical condition of the patient. Sedation or general anaesthesia may occasionally be required for very anxious patients. Digital subtraction angiography (DSA) allows greater clarity of the arteries (Belli and Buckenham, 1995). This is a computerized method of angiography without background information, e.g. bones and bowel.

The role of the nurse in providing holistic care is of vital importance, as promoting a healthy lifestyle will enable patients to make lifestyle choices to try to improve their own health and quality of life. Influencing lifelong health beliefs and smoking, eating and exercise habits in this patient group provides a challenge to the nurse. The nurse, whether a novice ward nurse or an experienced nurse specialist running nurse-led services, will need to gain the patient’s active participation in decision-making and actions in order to bring about change to slow disease progression. Factors affecting adherence and understanding of a patient’s self-motivation are essential in effecting changed behaviour. Control of this chronic condition and prevention of complications will depend on the careful assessment of the patient’s risk factors as discussed earlier, and strategies to manage them, especially smoking.

Medication concordance is vital, and patients should be advised of the importance of taking medications regularly, such as antihypertensives, diabetic drugs, statin and antiplatelet therapy. The latter medication, such as aspirin, reduces the frequency of thrombotic events in peripheral arteries and reduces overall cardiovascular mortality in claudicants by reducing blood viscosity (Antithrombotic Trialists Collaboration, 2002).

Stress management is also important, as the body’s response to life pressures and anxieties is to release adrenaline (epinephrine), which increases the heart rate, blood glucose and cholesterol levels. Consequently, the body becomes stressed, resulting in hypertension, which eventually contributes to the development of atherosclerosis. Teaching the patient stress management strategies, such as relaxation techniques, taking regular exercise and avoiding excessive alcohol or food consumption, is equally important.

Exercise is the mainstay of treatment for patients with claudication and has been shown to improve pain-free walking distance (Hiatt et al., 1991, Lungren et al., 1988, Patterson et al., 1997 and Perkins et al., 1996). It aids in the development of collateral circulation, which may help prevent ischaemia in the affected leg. A Cochrane Review recommends exercise as a key component of management of intermittent claudication (Leng et al, 2002). However, it has yet to be established what an ideal exercise programme should be, although supervised, structured programmes are more beneficial (Bendermacher et al., 2006 and Cheetham et al., 2004). In addition, walking exercise of 30 minutes at least three times a week, and walking to near-maximal pain, will achieve greatest improvement in patients (Gardner and Poehlman, 1995). The TASC working group (2000) recommends that exercise therapy (preferably supervised) should always be considered as part of the initial management of patients with intermittent claudication. Despite the evidence and recommendations, supervised programmes are not readily available in primary or secondary health settings. Some patients may not be willing to wait for symptom improvement with exercise, or are more likely to not have access to suitable programmes.

Percutaneous transluminal angioplasty (PTA) has become an established treatment for moderate to severe claudication, limb-threatening disease with ischaemic rest pain and to help facilitate healing of ischaemic ulcers. Angioplasty is performed under local anaesthesia and therefore carries a lower overall risk than surgery. Recent advances in technique have made day case angioplasties possible in some centres for patients with intermittent claudication (Cleveland et al, 2002).

Short stenosis or occlusion of iliac, femoral and popliteal arteries can be effectively treated by angioplasty. The procedure involves the insertion of a balloon catheter, which is passed into the lumen of the vessel, usually via the femoral artery, under local anaesthesia. The catheter is advanced to the site of the atheromatous plaque, and the balloon inflated, dilating the stricture, and hence improving the patency of the lumen of the vessel (Fig. 22.6A).

Other techniques such as atherectomy and insertion of stents can be combined with angioplasty. Atherectomy (Fig. 22.6B) uses high-speed revolving cutters to cut and remove an obstructing thrombus, whereas expandable metal stents can be inserted to prevent restenosis at the angioplasty site (Fig. 22.6C).

This is the coring out of the atheromatous plug using a ring stripper inserted into the artery lumen; it is now more commonly used for common femoral or carotid artery stenosis.

This bypass extends from the distal aorta to the common femoral arteries and is performed for stenosis or occlusion of the aorta or iliac vessels, using synthetic graft material. Patients with aorto-iliac disease will often present with bilateral buttock/hip claudication and impotence.

This bypass is performed for occlusion in the superficial femoral artery.

This bypass is performed for occlusion in distal vessels in patients with severe critical ischaemia who may have accompanying gangrenous lesions in the foot. The graft extends from the femoral artery to either the peroneal or tibial artery in the leg or foot. Distal bypass surgery can be a lengthy and clinically demanding procedure that may also require surgical debridement of gangrenous foot lesions at the end of the arterial reconstruction.

Extra-anatomical grafts may be considered for patients who are too unfit for major abdominal surgery and are at risk of limb amputation for critical ischaemia. These synthetic grafts are routed extraperitoneally through subcutaneous tissue to bypass the diseased vessel. The axillary and femoral arteries lie close to the skin surface, making the procedure more rapid and straightforward than more invasive bypassing. Although this type of bypass is less traumatic for patients, the patency rates are much lower than for aorto-iliac reconstructions (Beard, 2000).

This graft is performed for aorto-iliac occlusion.

This graft is performed for iliac artery occlusion.

Thorough multidisciplinary assessment of the patient is required. The aim of surgery with critical leg ischaemia should be a pain-free patient with a functioning limb. Primary amputation may need considering as an option if there is severe tissue necrosis which prevents weight bearing of the foot, fixed flexion deformity of the limb, or in very frail patients with severe medical problems who could not withstand a lengthy anaesthetic. Acquiring informed consent will require lengthy discussion with the patient and relatives, taking into consideration all these factors.

The patient should be fully informed of the bypass technique and the nurse will need to explain all pre- and postoperative care requirements. Due to the complexity of bypass surgery, the use of diagrams as a teaching aid may be useful for explaining the position of the intended grafts.