BLOCK IN THE ERETOR SPINA PLANE (ESP BLOCK) IN PATIENTS UNDERGOING MYOCARDIAL REVASCULARIZATION SURGERY: PROSPECTIVE, RANDOMIZED, DOUBLE-BLIND, PLACEBO CONTROLLED CLINICAL STUDY.

• Grant number: 24/20458-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2025
• End date: December 31, 2025
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Filomena Regina Barbosa Gomes Galas
• Grantee: Gustavo Meneses Dantas
• Host Institution: Instituto do Coração Professor Euryclides de Jesus Zerbini (INCOR). Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Submuscular regional blocks in deep fascia guided by ultrasound and special needles in cardiac surgery have gained enormous importance in terms of shortening intubation time, facilitating respiratory physiotherapy, reducing the use of opioids and reducing their negative consequences. Regional anesthesia is part of the current concept of multimodal analgesia in surgery, within the process of accelerating postoperative recovery.This is a clinical, prospective, randomized, double-blind, placebo-controlled study with the inclusion of 78 patients who underwent elective coronary artery bypass grafting at the Instituto do Coração of HCFMUSP. Patients will be randomized to one of two treatment strategies: local anesthetic or placebo in a 1:1 ratio. All patients will undergo standardized general anesthesia at the institution and after anesthetic induction, with the patient on mechanical ventilation and catheterized central and arterial accesses, erector spinae blockade will be performed. Blockade in both groups will be performed by the study researcher and anesthesia by the institution's anesthesiologist.To ensure masking of treatment, pharmacists (non-blinded staff) at the surgical center pharmacy will dispense study medications (ropivacaine or placebo) and Contiplex C catheters to the graduate student on the day of surgery and according to the list of randomization. For the local anesthetic treatment group (group I), the graduate student must aspirate 20 mL of the 0.2% ropivacaine solution (100 mL bags) in two 20 mL syringes and 10 mL of the solution in a 10 mL syringe, totaling 50 mL of the solution. In the placebo group (Group II), the graduate student must aspirate 2 syringes of 20 mL and 1 syringe of 10 mL, totaling 50 mL of 0.9% saline solution (100 mL bags). The remaining 50 mL in the bag (ropivacaine or placebo) must be returned to the pharmacy for correct disposal in an appropriate container.According to randomization, patients will undergo regional blocks as follows:In both groups, the patient will be positioned on the side to perform the blockade. Needling will be performed in a plane, introducing the needle and following its path, positioning its tip in the transverse process. Then, distilled water is deposited between the transverse process and the fascia of the erector spinae muscle, accompanying the divulsion of the fascia, and once the space is confirmed, the syringes will be exchanged for syringes containing the study medication (Ropivacaine 0.2% or placebo 0.9% SF), according to randomization. Then, 25 ml of Ropivacaine or placebo will be injected on each side of the thorax and after puncture and infusion of the initial dose, a catheter (Contiplex C, Bbraun®, Germany) will be introduced on each side of the thorax, also under ultrasound guidance. After fixing the catheters, the patient will return to horizontal dorsal decubitus (DHD) to start the surgery.All patients will undergo the institution's standard management: multimodal analgesia with common analgesics (dipyrone 4 to 8 g/day or paracetamol 1500 to 2250 mg/day), tramadol 200 to 400 mg/day, in addition to rescue analgesia if necessary. (morphine 02 mg). The PCA pumps will be programmed with a maintenance flow of 4 ml/hr and a bolus of 06 mls, with a minimum interval between shots of 60 minutes. The PCA and respective catheters will be removed on the third postoperative day (POD).Patients will be monitored from the point of view of pain until the 5th postoperative day and throughout the hospital stay to monitor secondary outcomes. Postoperative pain assessment will be performed using a numerical verbal scale at rest and during movement. In addition, patients will be followed up after discharge at 30 days and 6 months to assess chronic pain using the brief pain inventory performed over the phone.