FN emerges below the inguinal ligament lateral the femoral vein and artery. It is covered by, and separated from the vascular bundle by the fascia iliaca. Overlying fascia iliaca, there is fascia lata which runs together with the fascia iliaca laterally. The fascia iliaca compartment within the pelvic brim also contains the lateral cutaneous nerve of the thigh laterally. This nerve supplies sensory supply to the lateral thigh.
|Red dot on the image above represents the site of injection. Note, it is at least 2-3cm lateral from femoral artery unlike femoral block.|
- Patient not co-operative or refusing
- Allergic reaction to Local
- Infection over the site
- Previous femoral-bypass surgery
- Anticoagulation – INR >1.5 (Relative)
1 FIB Needle
1 Injection needle 25G
1 Drawing Up needle 18G
1 Syringe 5 ml
2 Syringes 20 ml
5 Gauze swabs
- Place the patient supine and obtain Verbal/Written consent
- Do a neurovascular exam prior to the block
- Follow Aseptic precautions
- Draw a line between ASIS and Pubic Tubercle and divide it into 3 parts (see image below)
- Point of injection is 1-2cms inferior to this line at the junction of lateral and middle 1/3 (i.e 1cm inferior to the junction of medial 2/3 and lateral 1/3)
- Feel for femoral artery and ensure that you are at least 3-4 cm lateral to it.
- Anesthetise skin with 2-3 ml 1% Lidocaine
- Inject Bupivacaine - Advance the needle and feel for two distinct “pops” (fascia lata and then fascia iliaca). Advance the needle a further 1-2mm.
- Aspirate, and if negative inject slowly. There should be no resistance to injection. If there is, it means you are too deep. Withdraw the needle until injection is easy. There should be no pain or paraesthesia on injection. Inject slowly, aspirating with every 2-3 mls.
- Withdraw the needle at the end of the procedure and apply a little pressure to the area for up to two minutes. The idea to to ensure maximum drug is delivered proximal to the site of injection and thus reaching all the three nerves.