Effect of Intravenous Vitamin C and N Acetylcysteine on Postoperative Pain and Opioid Consumption after Laparoscopic Gynaecologic Oncosurgeries: A Randomised Controlled Study

Abstract

Introduction: Postoperative pain is one of the common causes of increased postoperative morbidity and delayed recovery. Pain causes adverse effects such as hypertension, tachycardia, myocardial ischaemia, decreased alveolar ventilation, poor wound healing, and postoperative morbidity. Vitamin C and N-acetylcysteine (NAC), which is a novel co-analgesic, are being studied to reduce postoperative pain and opioid consumption. Aim: To study the effect of intravenous Vitamin C and NAC on postoperative surgical pain and opioid consumption after laparoscopic gynaecologic oncosurgeries. Materials and Methods: The present study was a randomised controlled study conducted at the Department of Anaesthesiology, Kidwai Memorial Institute of Oncology, Bengaluru, Karnataka, India on 300 patients of American Society of Anaesthesiologists (ASA) physical status 1 and 2 scheduled for laparoscopic Gynaeconcology surgery after obtaining written informed consent. All the selected patients were randomly allocated into three groups. Group P was the control group in Group N patients received intravenous injections of NAC (50 mg/kg) and vitamin C infusion (50 mg/kg) in Group C. Patients were explained about the visual analogue pain scale preoperatively. In the postoperative period, VAS scores were recorded and noted along with the rescue analgesics received and side-effects. Results: Haemodynamic variables were comparable among all three groups. The number of patients who had VAS scores of more than 4 was lower in group C (Vitamin C) at various time intervals when compared to the NAC and placebo groups. It was also statistically significant at 45 minutes, 60 minutes, 90 minutes, 150 minutes, 180 minutes, 300 minutes, and 10 hours (p-value=0.014, <0.001, <0.001, <0.001, 0.003, 0.005, 0.006, respectively). Postoperative opioid consumption was significantly reduced in group C (Vitamin C) compared to the other two groups (p-value<0.001). Conclusion: Intraoperative Vitamin C usage reduced postoperative pain and fentanyl consumption in the postoperative period, and NAC can be used as a part of multimodal analgesia.

Keywords

• analgesia
• co-analgesics
• fentanyl
• pain scores