Analgesic Effect of IntraPeritoneal LIGNOcaine in Gynaecological Open Surgery

The incidence of postoperative pain is highly prevalent among surgical patients. Inadequate postoperative pain control can slow the recovery and it increases the risk of postoperative complications, namely lung collapse and chronic pain. Although morphine is the one of the gold standard analgesia option for postoperative pain, it comes with many unwanted adverse effects, such as severe nausea and vomiting, low blood pressure and dizziness. Thus, multimodal analgesia regime, including local anaesthetic (lignocaine) is strongly advocated for postoperative analgesia. The normal route of lignocaine is injected into vein for the properties of analgesia and anti-inflammatory. It exerts its effect via the systemic absorption of drugs to block the central neuronal pain transmission. In recent years, studies have demonstrated that instillation of lignocaine inside abdominal cavity can reduce internal organ pain by blocking free nerve ending inside abdomen with minimal systemic absorption of drug and lower complications of systemic toxicity of local anaesthesia as compared to the intravenous route of lignocaine. Several RCTs showed the beneficial effect of intraperitoneal lignocaine for the reduction of postoperative visceral pain after laparoscopic surgery. However, gynaecological open surgery (cystectomy, hysterectomy) involves greater degree of manipulation and trauma on the internal organs with greater visceral pain, resulting in longer duration of hospitalisation and delayed functional mobility recovery. It is believed that the intraperitoneal lignocaine reduces inflammatory response after surgery and exert analgesia effect by blocking the neural signal transmission at site of tissue injury. Therefore, it is important to conduct this study to examine the analgesic effect of intraperitoneal lignocaine in women undergoing gynaecological open surgery.