A vascular access system for accurately locating body structures, such as blood vessels within a patient includes a flexible probe for applying {HEAD ~ Doppler ultrasonic techniques} that has {TAIL ~ a relatively adjustable length} relative to a needle assembly 
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A vascular access system for accurately locating body structures , such as blood vessels within a patient includes a flexible probe for applying { HEAD ~ Doppler ultrasonic techniques } that has { TAIL ~ a relatively adjustable length } relative to a needle assembly
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH