Intermittent Epidural Bolus Versus Epidural Infusion for Posterior Spinal Fusion After Adolescent Idiopathic Scoliosis

Patient-controlled Intermittent epidural bolus versus epidural infusion for posterior spinal fusion after adolescent idiopathic scoliosis.

Scoliosis surgery is commonly performed in adolescent due to idiopathic scoliosis. It is reported that the postoperative pain after scoliosis surgery that occurs due to Surgical trauma and severe reflex muscle spasm be severe and excruciating. There are many methods for postoperative pain management. It is used often opioid , paracetamol and non-steroidal anti-inflammatory drug with patient- controlled intravenous analgesia (IV-PCA). In addition; intrathecal opioids, one catheter epidural with intermittent dosing bolus of morphine or continuous infusion (either opioids or local anaesthetics or both), double epidural catheter with continuous infusion and intravenous ketamine infusion were preferred other postoperative pain management models.

Epidural analgesia is accepted procedure with the efficacy and safety profile for postoperative pain management in major orthopedic surgery including scoliosis surgery. Epidural analgesia techniques commonly have been used in continuous infusion of local anesthetics with or without opioid. It was emphasized that there was not adequate data in the literature to provide argument concerning the use of epidural opioids after spinal surgery. The objective of this study was to compare the effects and side effects patient- controlled intermittent bolus epidural analgesia (PCIEA) and patient- controlled continuous epidural analgesia (PCCEA) with morphine for postoperative pain control in adolescent idiopathic scoliosis after posterior spinal fusion.

Methods The study was conducted after obtaining written consent from all patients and guardian, approval from the Inonu University Faculty of Medicine Ethics Committee. This prospective randomized controlled double-blinded study was conducted 47 patient between 8-18 years, American Society of Anesthesia Classification (ASA) I-II, with idiopathic scoliosis, scheduled for elective posterior spinal fusion.

Patients with a history of allergy to the drugs used in the study protocol, drug abused , preoperative neurologic deficit, inability to use a visual analogue scale, pulmonary, cardiac and neuropsychiatric disorders were excluded. Exclusion criteria during the study were accidental perforation of dura, faulty epidural catheter placement, postoperative neurologic deficit or uncontrollable nausea, vomiting and pruritus.

The patients who were not premedicated were instructed on the visual analog scale (VAS) and the patient-controlled analgesia (PCA) device that was implanted during the postoperative period.

Patients were divided into two groups using the envelope drawing method. Patients who received epidural morphine with PCIEA represented Group 1, epidural morphine with PCCEA represented Group 2. The anesthetist who collected data and the patients were blinded.

All operations were performed by the same surgical team. The posterior instrumentation with pedicle screws was applied to thoracic and lumbar spine. Epidural catheter was inserted by surgeon under direct visualization at the midpoint of the incision and advanced 5-6 cm cephalad to thoracic 4-5 before surgical closure. Intubated patients was taken to in the reanimation intensive care unit after operation, IV acetaminophen 15 mg / kg was started before extubation and repeated every 6 hours.

After extubation and a neurological examination, patients in the PCİEA group received morphine 50 µg/kg in 10 mL bolus, lockout time 1 hour, no infusion. In Group 2, PCECA infusion the following initial setting loading morphine 0.02mg/kg in 8mL, was maintained 0.01 mg/kg continuous infusion 4mL, 0.05 mg/kg 2mL bolus dose. 30 minute lock-out interval. 4 hour limit was 4 mg/kg.

Pain score, morphine usage, postoperative nausea and vomiting, pruritus, rate their satisfaction ,sedation scores and motor block were assessed by researchers who were blinded to the study groups at postoperatively 2., 4., 6., 8., 12., 18., ve 24.hour, in all patients.