title: Use of hand-held Doppler to identify difficult forearm veins for cannulation.
mesh_terms: D002406:Catheterization, Peripheral / Q000379:methods*; D005542:Forearm / Q000098:blood supply*; D006801:Humans; D018608:Ultrasonography, Doppler; D018084:Ultrasonography, Interventional; D014680:Veins / Q000000981:diagnostic imaging