BACKGROUND: Postoperative Pain control in Open Nephrectomy is one of the leading concerns of patients who underwent the procedure. Many efforts were made to determine the most efficient concoction for pain control, and studies have shown that opioids were the most efficient in reducing pain; however, it was observed that these opioids would produce side effects which hinders the goals of Enhanced Recovery after Surgery (ERAS). Lidocaine Intravenous infusion on the other hand, has been introduced as an adjunct as an opioid sparing alternative. It has been reported that it is effective in managing pain in different types of surgeries with promising results. OBJECTIVE: To determine the effectiveness of perioperative intravenous lidocaine infusion as an adjunct in postoperative analgesia in patients undergoing open nephrectomy. METHODOLOGY: This is a randomized, double-blind, placebo-controlled study among patients admitted at The Institution, who underwent Elective open nephrectomy. Randomization into two treatment groups was done via draw lots. Both groups received treatment 30mins prior to cutting time wherein induction of anesthesia using Midazolam 1 mg IV, Fentanyl 50mcg/dose IV, Propofol 1 % 1 mg/kg IV, with sevoflurane were used and adjusted accordingly. Rocuronium 0.6mg/kg IV was used as muscle relaxant. During induction, Group A received Lidocaine 2% (200mg) diluted to D5W in a 50ml syringe and infused intravenously via Target controlled infusion (TCI) with a maintenance rate of 40mcg/kg/min infusion intra-operatively at the start of cutting time. On the other hand, Group B will receive PNSS in a 50ml syringe. Postoperative outcome measured for this study includes numeric pain scores at 1, 2, 1 2, and 24 hours post operatively, number of morphine rescue doses and presence of adverse drug reactions. RESULTS Patients who received lidocaine had significantly lower mean pain scores across all time periods (7.6±1.2 at 1 hr, 3.4±1.3 at 2 hrs, 2.5±0.8 at 12 hrs, and 1.5±2.0 at 24 hrs) compared to those who received placebo (5.4± 1.6 at 1 hr, 5.4± 1.6 at 2 hrs, 4.9±1.1 at 12 hrs, and 3.5±1.5 at 24 hrs) (pvalue= 0.0021 ). The mean pain scores of both groups significantly decreased starting from 1 hour to 24 hours after surgery (p-value=0.0000). Patients who received lidocaine had significantly lower mean number of rescue morphine (1 .9±2.1) compared to those who received placebo (5.6±2. 9) (p-value=0.0001 ). No patients had significant adverse reactions from the lidocaine group, while 6 patients (33.3%) had nausea from the placebo group (p-value=0.019). Conclusion: Peri-operative intravenous Lidocaine Infusion (IVLI) is effective in reducing postoperative pain during the first, second, twelfth and twenty-fourth hours after nephrectomy. Also, the administration of perioperative IVLI significantly lowered the number of needed rescue morphine.
Pain Management