Page 175 - Libro 2

10
Upper Extremity Arterial Duplex Scanning
Aaron Partsafas and Gregory L. Moneta
OBJECTIVES
KEY TERMS
axillary | brachial | radial | Raynaud’s syndrome | subclavian | Takayasu’s arteritis | thoracic outlet | ulnar
GLOSSARY
Raynaud’s syndrome a vasospastic disorder of the digital vessels
Takayasu’s arteritis a form of large vessel vasculitis resulting in intimal fibrosis and vessel narrowing
Upper extremity arterial examination uses compo- nents of the history and physical examination in conjunction with noninvasive and sometimes inva- sive studies. Duplex ultrasound examination is a key diagnostic modality when evaluating upper extrem- ity arterial disease. Upper extremity arterial disease occurs much less frequently than lower extremity ischemia, accounting for only about 5% of extrem- ity ischemia. Its low incidence and highly variable etiology causes considerable confusion in clinical practice. Causes of upper extremity symptoms re- lated to arterial disease include mechanical obstruc- tion at the thoracic outlet, embolism, trauma, digital artery vasospasm, and digital artery occlusion. In many cases, a thorough history and physical in con- junction with a duplex ultrasound examination will be sufficient to determine definitive management and minimize the use of arteriography. This chapter will review the arterial anatomy of the upper ex- tremities, identify the important anatomic variations that may be encountered, and will discuss common
thoracic outlet the superior opening of the tho- racic cavity that is bordered by the clavicle and first rib; the subclavian artery, subclavian vein, and brachial nerve plexus pass through this opening
vasospasm a sudden constriction of a blood ves- sel that will reduce the lumen and blood flow rate
clinical applications of upper extremity arterial du- plex scanning. Both normal and abnormal duplex findings, some of which are unique to insonation of the upper extremities arteries, are presented. Finally, a stepwise process for examination of upper extremity arteries is presented.
ANATOMY
Arterial duplex examination of lower extremity ar- teries is quite common compared to the evaluation of upper extremity arteries. For some, upper ex- tremity anatomy may be less well-known. Under- standing the normal arterial anatomy of the upper extremities, along with common anatomic variants, facilitates assessment of upper extremity arteries by duplex ultrasound (Fig. 10-1). Although Chapter 1 reviewed the vascular anatomy, some additional details of upper extremity vessels are described as follows.
List the blood vessels imaged during an upper extremity ultrasound evaluation
Identify normal and abnormal spectral Doppler waveforms
Describe the scanning techniques used to properly insonate upper extremity vessels
Define diseases that impact upper extremity arteries
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