At the end of this chapter, the learner will be able to:
Relate the pathological changes in the vascular anatomy to the formation of arterial and venous wounds.
Differentiate between arterial and venous wounds.
Perform a vascular screening and interpret noninvasive vascular studies for arterial and venous disorders.
Use the information obtained from vascular studies to develop a plan of care for arterial wounds (before and after surgery) and venous wounds.
Determine when and if surgical intervention is needed for patients with arterial and venous wounds.
Select the appropriate compression therapy for patients with lower extremity vascular wounds based upon vascular studies.
The vascular system is an intricate system of arteries, veins, and lymphatic vessels designed to transport the blood from the heart to the core and peripheral tissue, providing tissue with the oxygen and nutrients necessary to sustain life, and from the same tissue back to the heart and lungs for recirculation. (FIGURE 4-1) An interruption to blood flow in any one or more of the vessels can cause significant and critical pathologies that result in integumentary changes, wounds, or impaired healing. If the pathology is in the arterial system, the wound is termed ischemic; if it is in the venous system, it is termed venous. Both types have very defining characteristics and predictable vascular study results that are used to determine the optimal plan of care for the individual patient. This chapter focuses on the pathophysiology, prevention, and treatment of arterial and venous wounds; lymphatic disorders are discussed in Chapter 5.
Anatomy of the arterial and venous circulatory systems The circulatory system consists of the cardiac, arterial, venous, and lymphatic systems. The arterial system is further delineated into the macrocirculation (arteries large enough to be named) and microcirculation (capillaries and arterioles too small to be named). The lymphatic system is illustrated in Chapter 5.
Vascular diseases such as peripheral arterial occlusive disease (PAOD) and chronic venous insufficiency (CVI) cause the majority of lower extremity wounds; the majority of arterial wounds are caused by PAOD. The clinical spectrum of PAOD ranges from asymptomatic disease to mild claudication, to tissue loss or gangrene of the foot or lower extremity. When patients with PAOD have an ulcer or gangrene of the lower extremity, it is termed critical limb ischemia (CLI). The major cause of CLI is a reduction in distal tissue perfusion below the resting metabolic requirements usually associated with atherosclerosis; however, other conditions may cause wounds that appear to be arterial or ischemic. (TABLE 4-1) Diabetes mellitus (DM) is one of the most serious and prevalent of these disorders. The combination of DM and PAOD may lead to foot ulceration or gangrene, which may result in amputation. The overall risk of amputation ...