ABSTRACT
OBJECTIVE: Recent research has focused on the use of N-methyl-D-aspartate (NMDA) receptor antagonists for pain management. Several drugs are known to have this action, including ketamine, which exerts its main analgesic effect through NMDA receptor antagonism. This study aimed to evaluate the effect of low-dose ketamine infusion on opioid exposure for patients undergoing myomectomy surgery under general anaesthesia. METHODS: A total of 70 women were included in this prospective double-blind trial study. The patients included in this study were American Society of Anaesthesiologists physical status I-II, aged between 18 and 50 years and scheduled for laparotomy myomectomy surgery. Patients were randomised to receive either a bolus of 0.2 mg kg-1 of ketamine followed by a continuous infusion of 0.2 mg kg-1 hr-1 during the operation or a placebo of normal saline. Both groups also received morphine as needed for pain relief. The primary outcome was the total amount of morphine used during the intraoperative and postoperative periods. Intraoperative and postoperative mean blood pressure, heart rate and postoperative visual analogue scale for pain were assessed. RESULTS: Total mean morphine consumption was significantly lower in the ketamine group than in the control group (26±3.5 mg vs. 34.7±3.3 mg, respectively, p<0.05). However, there were no statistical differences between the groups regarding haemodynamics, postoperative pain score and complications. CONCLUSION: The use of ketamine in low infusion doses intraoperatively during an elective myomectomy procedure produced an opioid-sparing effect by reducing perioperative morphine consumption without significant side effects.
ABSTRACT
BACKGROUND AND AIMS: The use of dexamethasone as an adjuvant to local anesthetic rarely has been described. Some studies have demonstrated the analgesic effect of local spinal and systemic corticosteroids in combination with bupivacaine. It works by decreasing inflammation and blocking transmission of nociceptive C-fibers and by stopping the ectopic discharge of the nerve. The aim of this randomized controlled trial was to compare the efficacy of epidural levobupivacaine alone versus a combination of levobupivacaine with dexamethasone for labor analgesia. MATERIAL AND METHODS: This prospective double-blind trial included the 60 primigravidas during vaginal delivery with a cervical dilatation ≥4 cm and 50% effacement randomly assigned to one of two groups - Group A (n=30): epidural levobupivacaine 0.125% in normal saline in a total volume of 15 mL and Group B (n=30): epidural levobupivacaine 0.125% in normal saline combined with dexamethasone 4 mg in a total volume of 15 mL. At first request of analgesia, 10 mL of 0.125% levobupivacaine was administrated through epidural catheter. Further analgesia was provided with 8 mL of 0.125% levobupivacaine hourly. Primary outcome measure was the duration of epidural analgesia. Secondary outcome measures include pain score by Visual Analog Scale score before the block and 15 min following it, the total amount of levobupivacaine used, Apgar score and umbilical vein blood gas analysis, maternal satisfaction, and side effects recorded. RESULTS AND CONCLUSION: The duration of epidural analgesia was significantly longer (P < 0.05) upon adding dexamethasone to levobupivacaine. Total epidural levobupivacaine consumption was significantly lower (P = 0.05) in Group B. There were no statistical differences between the two groups regarding hemodynamics, pain score, neonatal outcome, and complications. Epidural dexamethasone plus levobupivacaine prolongs the duration of epidural analgesia during management of labor pain with hemodynamic stability and limited maternal and neonatal adverse effects.
