Ultrasound Blocks for the Anterior Abdominal Wall

5. Genitofemoral Nerve Block
Zhirajr Mokini
5. Genitofemoral Nerve Block | 53
Occasionally, the inguinal field block (IFB)/local infiltration
anesthesia (LIA) (see the detailed discussion in Chapter 7) seem
to fail due to pain experienced during spermatic cord
manipulation. In these cases, ideally, a block of the genital
branch of genitofemoral nerve (gGFB) should be performed
because local anesthetic infiltration into the inguinal canal
improves the efficacy of the block (Yndgaard 1994).
A selective gGFB is not possible except under direct
intraoperative vision (Rab 2001). The IIN and gGFN generally
enter the deep inguinal ring and run together into the inguinal
canal on the surface of the spermatic cord. In all cases the gGFN
innervates the cremaster muscle (Rab 2001).
The blind landmark for the inguinal canal that corresponds to
the underlying spermatic cord is the point on the skin, one
finger-breadth above the mid-point between the ASIS and the
mid-penopubic fold at the symphysis pubis (Hsu 2005). The
typical injection site for the gGFB is referred to be
superior-lateral to the pubic tubercle in order to inject the
anesthetic near the spermatic cord (Peng 2008). Caution should
be taken because at the pubis level the inferior epigastric vessels
are found respectively at 7.47 +/- 0.10 cm on the right and 7.49
+/- 0.09 cm on the left side from the midline (Saber 2004).