Local anesthetics are more powerful agents for the management of postoperative pain located, interrupt the transmission of harmful impulses through a locking mechanism of the cell membrane of the nerve fibers sodium channels and infiltration of tissues, and topical application can be used in spinal blocks, epidural, peripheral nerves.
Limitations include a limited duration of its action and systemic toxic reactions when they reach high levels in blood. Bupivacaine is one of the most commonly used agents when you want a long lasting, but the dose is limited by the cardiovascular toxicity that produces. Ropivacaine and levobupivacaine new stakeholders have a prolonged duration similar to that of bupivacaine and a lower cardiovascular toxicity and central nervous system (33)
Injection of local anaesthetics in surgical wound, is an attractive technique for the management of pain post-op for being simple, economical and be devoid of side effects. The infiltration can be carried out prior to the surgical incision (preventive analgesia) or at the time of closing the wound.
Local anesthetics in the incision, modulate pain peripheral by inhibiting the transmission of noxious stimuli of the site of the injury to the spinal cord and reduce the peripheral and central sensitization that occurs in response to surgical trauma, resulting in less pain post-op, lower requirements of painkillers and minor side effects associated with these.
This treatment modality has been described in different with and without placebo-controlled randomized studies and the results have been a significant reduction in the post-op pain and demand of opiate analgesics in moderate and minor surgical procedures. In major abdominal surgery, the results have been mixed, some studies have obtained good analgesic effects posoperatorios and in others they have been minimal, it is likely that this is due to different doses and techniques of infiltration have been used and the extent of tissue damage resulting in surgery in different abdominal surgical procedures (34,35).