2 Position the Patient and the Ultrasound
The key to a successful IV catheter insertion under ultrasound guidance is comfort. Both the patient and the provider need to be comfortable from start to finish. The position of the patient’s arm will need to be adjusted depending upon the chosen IV site, but the arm should be held at a height where you do not have to arch your back. Using an adjustable table under the patient’s arm with a sheet roll directly under the extended elbow is an optimal position (see Figure 2). The position of the ultrasound machine is also vital to success. The ultrasound should be placed on the opposite side of the arm being used for IV insertion. The screen should be angled to provide a continuous unobstructed view for real time insertion of the catheter (see Figures 2 and 3).
3 Use a Waterproof Transparent Dressing to Cover the Ultrasound Probe
Traditional probe covers may be bulky and cumbersome, and visualization may not be optimal depending on both the thickness of the cover and the amount of gel used underneath. By placing a waterproof transparent dressing directly over the probe, the need for the traditional probe cover is obviated. Make sure the transducer is clean and dry before applying, and after the procedure is completed, simply peel away the dressing (see Figure 4).
4 Place the Tourniquet High and Tight, or Possibly Place Two
To improve success with peripheral vein cannulation, providers typically use a tourniquet to obstruct the one-way flow of venous blood through valves, thus causing backflow with improved visualization of the target vein and decreased compressibility. Place the tourniquet as close to the axilla as possible when initially searching for an adequate vein. This will lead to better venodilation throughout the arm and will allow for improved visualization of potential cannulation sites. After a preferred site is found, consider placing the tourniquet closer to the desired location. One trick is to place a tourniquet below the target insertion point as well as above the targeted area to help create a closed loop. The two-tourniquet technique forces excess blood into the vein, creating a larger target with improved success rates of peripheral IV insertion. Using a blood pressure cuff inflated to 150 mmHg has also been shown to increase the size and decrease the compressibility of veins, which may also lead to higher rates of cannulation.6