Name:
Ultrasound Guided Femoral Nerve Block
Description:
Ultrasound Guided Femoral Nerve Block
Thumbnail URL:
https://cadmoremediastorage.blob.core.windows.net/294fd36f-7dcb-4924-834c-135199241218/thumbnails/294fd36f-7dcb-4924-834c-135199241218.jpg?sv=2019-02-02&sr=c&sig=l3Is7I7gvi1zO55cjVGZ3FGfG9MeDiZGoQYbdEUDJiI%3D&st=2023-06-07T08%3A08%3A23Z&se=2023-06-07T12%3A13%3A23Z&sp=r
Duration:
T00H03M48S
Embed URL:
https://stream.cadmore.media/player/294fd36f-7dcb-4924-834c-135199241218
Content URL:
https://asa1cadmoremedia.blob.core.windows.net/asset-6e144434-aa63-459c-8d92-457121a71315/Hadzic_04_Femoral20block-with20CR.mov
Upload Date:
2022-02-27T00:00:00.0000000
Transcript:
Language: EN.
Segment:0 .
Ultrasound-guided femoral nerve block.
Segment:1 Anatomy.
The femoral nerve lies lateral to the femoral artery. The nerve is covered by the fascia iliaca. Of note, the femoral vessels are enveloped in a separate fascial sheath, called the vascular sheath, that may not communicate with the femoral nerve. It is important to note that multiple fascial sheaths can be identified in this region.
Fascia lata is one of them, and should not be confused with the fascia iliaca sheath. Fascia lata appears more superficial and is not anatomically related to the femoral nerve. The arrows indicate the fascia iliaca. Lateral and superficial to the iliopsoas muscle is the sartorius muscle, which should not be confused with the iliopsoas muscle. We will now spend a few moments discussing the ultrasound anatomy of the femoral nerve block.
The ultrasound transducer is placed over the anterior thigh in the area of the inguinal crease. The ultrasound image shows the femoral nerve immediately lateral to the femoral artery. Ultrasound clearly depicts the fascial layers. The two layers of the fascia iliaca envelope the femoral nerve, which sits on the iliopsoas muscle.
The fascia lata is much more superficial, whereas the vascular fascia may not contain the femoral nerve.
Segment:2 Technique.
The technique begins with the disinfection of the skin. A small gauge needle is used to inject local anesthetic subcutaneously to decrease the discomfort during needle manipulation.
In this example, the needle approaches the femoral nerve with an in-plain technique and eventually enters between the two layers of the fascia iliaca. Injection of local anesthetic causes separation of the two layers of the fascia, and the distribution of local anesthetic is clearly seen enveloping the entire femoral nerve between the two layers of the fascia.
Often times, during the performance of a femoral nerve block, a motor response of quadriceps is elicited. If the motor response is present, it is important to ensure that the absence of the response with a current of less than 0.3 milliamps to decrease the risk of an intrafascicular injection. This particular ultrasound anatomy example demonstrates the dispersion of local anesthetic under the fascia iliaca laterally towards the sartorius muscle.
It is important to note that there are several large vessels in the vicinity of the femoral nerve. Therefore careful aspiration throughout the procedure is crucially important to avoid an inadvertent intravascular injection during the block.