To perform a USGFICB, two approaches exist. Both have the goal of injecting local anesthetic into the compartment lateral to the femoral nerve, which lies lateral and adjacent to the vascular bundle (see Figure 1). The two approaches are the infrainguinal (see Figure 2A) and the suprainguinal (see Figure 2B).
- High-frequency linear transducer (6–10 MHz) with sterile lubricant
- 0.5% ropivacaine (5 mg/mL): dilute 30 mL 0.5% ropivacaine into 30 mL 0.9% normal saline
- Max dose is commonly considered 3 mg/kg.
- Ropivacaine is the preferred local anesthetic due to its long-acting duration with a greater safety profile than bupivacaine.13
- Mixing of local anesthetics is not currently advised due to less predictable onset, duration, and potency.13
- 22-gauge blunt-tipped echogenic needle (Whitacre and Sprotte needles are blunt-tipped needles, which provide better tactile feedback when “popping through” the fascia lata and fascia iliaca.)
- IV tubing connected to a 30 or 60 mL syringe
- Chlorhexidine scrub or alcohol prep sponge
- Local anesthetic for cutaneous anesthesia (eg, 12% lidocaine without epinephrine)
- Personal protection equipment including sterile gloves
- Second provider present for assistance
- Airway supplies and 20% lipid emulsion available
With the above supplies prepared and on standby, perform a preprocedure scan to determine the patient’s specific anatomy. Prepare the selected injection site with chlorhexidine or isopropyl alcohol. A skin marker may help maintain proper orientation to the injection site. Next, flush the premixed 30 mL of ropivacaine and normal saline through the line and echogenic needle.