A Study to Compare Laparoscopic to Echographic Assisted Transversus Abdominis Plane Block in Laparoscopic Colectomy

The anterior axillary line is used as landmarks. After insertion of the optic trocar, the peritoneum is visualized. A 14 Gauge needle is inserted 2 cm cranially respect the taken landmark through the skin until the penetration of the internal and external oblique fascias, identified as sudden lowering of resistance. A solution of 15 ml of Ropivacaine (0.2%) is then injected. The procedure is performed then 2 cm caudal to the first landmark on the same side. The procedure is than repeated identically on the contralateral side.

Whilst the patient is in the supine position, a high frequency ultrasound probe is placed transverse to the abdominal wall between the costal margin and iliac crest. The needle is introduced in plane of the ultrasound probe directly under the probe and advanced until it reaches the plane between the internal oblique and transversus abdominis muscles. Then 15 ml of local anaesthetic solution is injected. The needle is than retracted until its tip is positioned in the fascial plane between the internal and the external oblique muscles and a second bolus of 15 ml of local anaesthetic is injected. The procedure is than repeated identically on the contralateral side.