A second technique involves a field block of the major branches suppylying the abdominal wall, to include the 10th, 11th, and 12th intercostals nerves and the illoinguinal and genitofemoral nerves (Busby, 1963). As shown in Figure 19-6, the foemer group of nerves is located at a point midway between the costal margin and iliac crest in the midaxillary line. Thelatter group is found at the lavel of external inguinal ring. Only one skin puncture is made at each of the four sites. At the intercostals block site, the transversalis fascia, avoiding injection of the subcutaneous fat. Approximately 5 to 8 mL of 0.5 percent lidocaine is injested. The procedure is repeated at a 45 degree angle cephalad and caudad to this line. The other side is then injected. At the ilioinguinal and genitofemoral sites, the injection is started at a site 2 to 3 cm lateral from the pubis tubercle at a 45 degree angle. Finally, the skin overlying the planned incision is inlected.