Approach Considerations
Therapeutic recommendations include single-agent antiplatelet agents for prevention of cardiovascular events in patients wth asymptomatic and symptomatic peripheral arterial disease (PAD). [2] These medications should be used in conjunction with efforts to reduce risk factors, including smoking cessation and exercise therapy. [20]
Statins have been linked to improved prognosis in other vasculopathies, including renovascular and cardiovascular events. [21] Although lacking an immediate effect on any vascular process, statins show promise in slowing the progression of atherosclerotic disease systemically.
When conservative measures fail to improve quality of life and function, endovascular procedures are considered. [1] However, the timing and need for revascularization are related to the general primary presentations of claudication, critical limb ischemia, and acute limb ischemia, in which urgent intervention is warranted for critical limb ischemia. [1, 2]
An emerging treatment for peripheral vascular disease (PVD) is the use of growth factor (delivered as genes or proteins) and cell therapy. The delivery of growth factors or cells to the ischemic tissue can locally stimulate the regeneration of the functional vasculature network, reperfuse the ischemic tissue, and salvage the limb. [22]
See also guidelines from the American Heart Association and American College of Cardiology (AHA/ACC) [12] and the Canadian Cardiovascular Society (CCS). [13]
Prehospital and Emergency Department Care
Prehospital care for PVD involves the basics: control ABCs (airway, breathing, circulation), obtain intravenous access, and administer oxygen. In general, do not elevate the extremity. Note and record the distal pulses and skin condition. Perform and document a neurologic examination of the affected extremities.
Early emergency department care involves attention to the ABCs, intravenous access, and obtaining baseline laboratory studies. Obtain an electrocardiogram (ECG) and a chest radiograph.
Treatment of either thrombi or emboli in the setting of peripheral vascular disease is similar. Empirically, initiate a heparin infusion with the goal of increasing activated partial thromboplastin time to 1.5 times normal levels. Acute leg pain correlated with a cool distal extremity, diminished or absent distal pulses, and an ankle blood pressure less than 50 mm Hg should prompt consideration of emergent surgical referral.
In some cases of emboli, intra-arterial thrombolytic agents may be useful. The exact technique of administration varies, in both dosage and time of administration. Remember that intra-arterial thrombolysis remains investigational. Obviously, such thrombolytic therapy is contraindicated in the presence of active internal bleeding, intracranial bleeding, or bleeding at noncompressible sites.
Surgical Care
Early surgical consultation in patients with acute limb ischemia is prudent. Depending on the case, the surgeon may involve interventional radiology or proceed operatively. Emboli may be treated successfully by Fogarty catheter (ie, an intravascular catheter with a balloon at the tip). The balloon is passed distal to the lesion; the balloon is inflated, and the catheter is withdrawn along with the embolus. This technique most commonly is used for iliac, femoral, or popliteal emboli.
Definitive treatment of hemodynamically significant aortoiliac disease usually takes the form of aortobifemoral bypass, which has a 5-year patency rate of approximately 90%. Those patients in whom peripheral vascular disease (PVD) becomes significant, however, often have a plethora of comorbid medical conditions, such as cardiovascular disease, diabetes, and chronic obstructive pulmonary disease, which increase procedural morbidity and mortality. Axillobifemoral bypass and femorofemoral bypass are alternatives, both of which have lower 5-year patency rates but have lower procedural mortality.
In a retrospective study that evaluated the long-term outcomes of 714 patients who underwent percutaneous procedures for popliteal and infrapopliteal peripheral arterial disease, those with diabetes (n = 418; 58.5%) were younger and had a higher prevalence of a history of coronary artery disease, heart failure, end-stage renal disease, and a previous contralateral limb amputation relative to nondiabetic patients. [23] Independent of baseline comorbidities, diabetes was associated with significantly higher all-cause mortality, ipsilateral major amputation, and major adverse events.
A systematic review and meta-analysis of data from five databases over a period of 20 years (2000-2019) included 17 observational studies with 13,140 patients to examine outcomes of lower extremity peripheral arterial interventions in those with and without chronic kidney disease (CKD) and/or end-stage renal disease (ESRD) relative to individuals with normal renal function. [24] Patients with CKD/ESRD had a higher incidence of target lesion revascularization, major amputations, and long-term mortality; these data were statistically significant for the latter two factors, regardless of the type of intervention (endovascular vs open surgery). However, the higher rates of target lesion revascularization in those with CKD/ESRD were only seen with endovascular interventions; there were no differences for open surgical approaches. [24]
In a study that assessed the long-term clinical impact of post endovascular therapy ABI improvement for peripheral arterial disease in 1307 consecutive patients (710 aortoiliac and 597 femoropopliteal lesions), investigators found that an increase of ABI of at least 0.15 following a successful procedure was independently predictive of "freedom from a composite of target limb revascularization and major amputation, irrespective of the locations of the treated lesions and the preprocedural ABI." [25]
Some areas of arteriostenosis can be revascularized with percutaneous transluminal coronary angioplasty (PTCA). If the occlusion is complete, a laser may be useful in making a small hole through which to pass the balloon. Restenosis is a concern with PTCA, particularly for larger lesions. Stents and lasers are still considered experimental.
An initial study showed promise in relieving the pain of PAD with topically applied lidocaine spray. Suzuki et al studied 24 subjects with PAD and noted a significant drop in pain associated with PAD by applying an 8% lidocaine metered dose spray to the affected areas. Blood levels of lidocaine were minimal, and this technique may have therapeutic potential for those affected with focal PAD pain. [26]
Long-Term Monitoring
Patients who have significant PVD but whose illness is not so severe or acute that it requires inpatient treatment may be discharged with appropriate follow-up. However, counsel these patients regarding the potential effects of various activities and medications on the course of their illness. Advise patients to stop smoking and to avoid cold exposures and medications that can lead to vasoconstriction, including medications used for migraines and over-the-counter medications.
Some recreational drugs (eg, cocaine) may have a deleterious effect on peripheral arterial tone, and beta-blockers may exacerbate the condition.
Consultation with providers who will be following the patient after discharge from the emergency department is advised when making decisions regarding the discontinuance of medications used for chronic medical conditions.