Laparoscopic Guided vs Ultrasound Guided Transabdominal Plane Block in Minimal Invasive Colorectal Surgery; a Comparison Between Time of Procedure and Efficacy on Pain Relief and Postoperative Opioid Consumption.

At Danderyds hospital in Stockholm, since 2010, we are conducting patient care according to international evidence based Enhanced Recovery After Surgery (ERAS) protocols. Within colorectal surgery Danderyds hospital has been appointed ERAS Centre of Excellence due to documented favorable clinical results and a particularly suitable infrastructure for clinical research. The protocol comprises of 24 evidence-based interventions aimed at reducing so called surgical stress and promote early recovery after surgery. All interventions are executed in the same way for all patients. Optimal post-operative pain relief constitutes one of the 24 interventions and within this section a few methods are recommended. Transversus abdominus plane (TAP) block is one of those, and have been shown to reduce post-operative pain, reduce opioid consumption and elevate mobilization after surgery.

A TAP block is performed by injecting local anesthetics into the nervous plane in between the transverse and external muscles in the abdominal wall, and thereby blocking the nerves responsible for transmitting pain from the laparoscopic holes created during surgery.

Normally this TAP blockage is performed by the anesthesiologist using ultrasound to guide the needle for injection into the right plane of the abdominal wall. A procedure that can be cumbersome and that in our hospital setting takes around 30 minutes and is executed directly after the surgery but before the patient is alleviated of narcosis.

A novel technique has recently been described to guide the needle into the right position for the TAP block. In this technique the surgeon will use the laparoscopic camera and the port holes already made during surgery to visualize the inside of the abdominal wall, and by landmarks and a specially described bulging of the peritoneum as a marker, guide the needle from the outside and inject local anesthetics into the right plane. This method described by earlier studies has a procedure time at around 5+-1 minutes and has the benefit of not needing ultrasound or any other equipment not already present for the surgical procedure.

In this study we aim to include participants selected for elective robotic-assisted or laparoscopic minimal invasive surgery of the colon or rectum, where a TAP block is normally performed. The participant will be randomized to either a TAP block performed by the surgeon using laparoscopic guidance or by an anesthesiologist using ultrasound guidance. The intended surgery in itself will not be altered.