ESP Block Versus Wound Infiltration for Laminectomy

Spinal surgery is often burdened by perioperative pain and its treatment presently represents a challenge for anesthetists. An inadequate intra and postoperative analgesic therapy leads to a delay in the mobilization of the patients, prolonged hospital stay and thromboembolic complications, as well as the onset of chronic pain syndromes . Effective pain treatment can help improve surgical outcome for patients undergoing spinal surgery. From the pathophysiological point of view pain in vertebral surgery can originate from different anatomical structures: vertebrae, discs, ligaments, dura mater, facet joints, muscles and skin-subcutis. The terminal innervation of these tissues originate from the dorsal branches of the spinal nerves, and this represents a target a multimodal approach to perioperative analgesia in vertebral surgery. Systemically administered drugs such as NSAIDs, opioids, ketamine, intravenous lidocaine could benefit from the addition of locoregional therapies such as neuraxial blocks (anesthesia peridural or subarachnoid) or as shown more recently by other anesthesia techniques locoregional ultrasound-guided In recent years the anesthesiological interest has focused on the Erector Spinae Plane Block (ESPB). First described by Forero et al, it is a paraspinal interfascial block targeting the dorsal and ventral branches of the spinal nerves just after their emergence from the spinal cord. In the ultrasound-guided technique the local anesthetic is injected between the deep fascia of the muscle itself and the transverse processes of the vertebrae at the level interested. The aim of this study is to evaluate the efficacy of ESPB when compared to wound infiltration in patients undergoing laminectomy

Both arms will receive the same treatment (Wound infiltration and ESP block) after general anesthesia induction (Participant masked to intervention) Drugs will be prepared after randomization by a physician not involved in the care of the patients and not involved in the study, and labelled as WOUND INFILTRATION and ESP block. One syringe will contain local anesthetic, the other normal saline (Care Provider masked to intervention, Investigator masked to intervention) Outcome assessor will be not involved in other part of the study and will be not aware of the intervention (Outcome assessor masked to intervention)

Patient will receive ESP block one level above surgery with ropivacaine 0.35% 20 ml per side Patient will receive preoperative wound infiltration with Saline 40 ml

Patient will receive ESP block one level above surgery with Saline 20 ml per side Patient will receive preoperative wound infiltration with ropivacaine 0.35% 40 ml

Bilateral ultrasound guided injection of saline in the erector spinae plane (below erector spinae plane muscle group and above the transverse process of the vertebra)

Blinded injection of saline in the skin, subcutaneous tissue and muscles at the site of surgical incision

Bilateral ultrasound guided injection of local anesthetic (ropivacaine 0.35%, 40ml) in the erector spinae plane (below erector spinae plane muscle group and above the tranverse process of the vertebra)

Blinded injection of local anestetic (ropivacaine 0.35%, 40ml) in the skin, subcutaneous tissue and muscles at the site of surgical incision.

Inclusion Criteria: -Planned 1 or 2 level surgical laminectomy Exclusion Criteria: Allergy to local anesthetics Refusal of consent Uncompensated cardiopathies, nephropathies, liver disease or peripheral neuropathies Hemopathies that predispose to bleeding Gastrointestinal ulcer or bleeding Local infection Psychiatric or neurological disorders (except those attributed to primary disease for which intervention is planned) History of abuse (or use in the 24 hours prior to surgery) Alcohol addiction ASA > 3