Several studies have demonstrated that for patients with intravenous access that is difficult, ultrasound guidance leads to improved success rates with a decreased number of percutaneous punctures, decreased time to intravenous access, and fewer complications than standard techniques for PIV cannulation.^1-4 Ultrasound guidance also has been shown to aid nursing personnel in difficult-access patients.⁴

Clinical Indications

Emergency physicians should consider placement of an ultrasound-guided peripheral intravenous line (UGPIV) when attempts to obtain peripheral intravenous access by standard methods have failed, and in patients with known difficult PIV access without palpable peripheral vessels. (See peripheral intravenous access algorithm on page 22.)

How to Place a Peripheral Intravenous Line Using Ultrasound Guidance

• Patient positioning: The most common area for UGPIV placement will be the antecubital fossa region. The patient’s forearm should be extended to maximize accessibility for the ultrasound probe. In a supine patient, the easiest area to attempt UGPIV placement will most likely be on the volar aspect of the patient’s forearm. (See image 1 and image 2.)
• Probe selection: The high-frequency linear array probe should be used, as it provides higher resolution of the superficial areas of soft tissue. The flat footprint of the linear array probe is less cumbersome and less prone to slip off of the vessel of interest than the curved footprint of the high-frequency endocavitary probe.
• Supplies: A longer intravenous catheter, usually more than 1.5 inches, may be necessary, as the veins used for attempted UGPIV access may be deeper than those veins that are palpable. Sterile ultrasound gel should be used, as infection may be a complication with any type of intravenous access. Also remember that a tourniquet should be placed both for standard PIV and UGPIV attempts to make the vessel easier to cannulate.
• Vessel selection: After cleaning the skin with an alcohol swab, apply an adequate amount of sterile ultrasound gel to the area where the attempt will be made. Consider the use of local anesthetic when attempting cannulation of deeper veins.

Probe Orientation

Two techniques, short axis and long axis, have been described for placing a UGPIV.5 This article will address the short-axis technique, because novice sonographers may have improved cannulation times with this method, compared with the long-axis technique.⁵