A laparoscopic approach offers several advantages over an open procedures; potentially
reduces the surgical stress and fluid shifts that may accompany it; in addition there is less
need for postoperative analgesia, reduction of postoperative respiratory and wound
complications.
Despite the minimally invasive nature, pain can be moderate to severe in the immediate
postoperative period that requires multimodal analgesia. Inadequate control of post-operative
pain leads to several unwanted adverse events ranging from patients' discomfort and prolonged
immobilization to thromboembolic phenomenon and pulmonary complications.
Transversus abdominis plane (TAP) block is a type of peripheral nerve block that involves
innervation of the anterolateral abdominal wall. With the aid of ultrasound, local anesthetic
(LA) is injected into the transversus abdominis fascial plane, where the nerves from T6 to L1
are located.
Ultrasound TAP block is accompanied by a good pain relief and reduced intraoperative and
postoperative opioids requirements after laparoscopic surgery. In this case a bilateral TAP
block is necessary because the abdominal skin incisions for the ports of laparoscopic
procedure are performed on both sides.
Unfortunately, TAP block duration is limited to the effect of administered LA. Recently,
adjuvant medications were added to LA to prolong the effect of TAP block. Dexmedetomidine is
a selective alpha 2 (α2) adrenergic agonist with both analgesic and sedative properties. Its
use with bupivacaine either epidurally or intrathecally is associated with prolongation of
the LA effect. A major advantage of dexmedetomidine is its higher selectivity compared with
clonidine for α2A receptors, responsible for the hypnotic and analgesic effects of such
drugs.10 Clonidine action, similar to local anesthetic action, and its interaction with local
anesthetics have been explained by three possible mechanisms. First, clonidine blocks Ad and
C fibers. Secondly, clonidine may cause local vasoconstriction, thus decreasing local
anesthetic spread and removal around neural structures. Thirdly, clonidine used in peripheral
blocks intensifies and prolongs analgesia.