Lidocaine and Magnesium and Ketamine in Gynecological Surgery

The aim of this study will be to investigate the effect of a combination of intravenous infusions of lidocaine and magnesium versus a combination of intravenous infusions of lidocaine and ketamine versus an intravenous infusion of lidocaine alone on recovery profile, quality of recovery and postoperative pain after elective gynecological surgery

Inadequately treated postoperative pain after gynecological surgery may untowardly affect early recovery and also lead to the development of chronic pain. Opioid-based analgesia is associated with side-effects, such as respiratory depression, postoperative nausea and vomiting and occasional induction of tolerance and hyperalgesia. Therefore, in recent years research has focused on the quest for non-opioid-based regimens for perioperative analgesia in the context of multimodal analgesic techniques. These techniques have been shown to possess significant advantages, such as allowing earlier mobilization after surgery, early resumption of enteral feeding and reduced hospital length of stay.

In this context, the intraoperative intravenous injection of lidocaine has been reported to improve postoperative pain control, reduce opioid consumption and improve the quality of postoperative functional recovery after general anesthesia. Intraoperative infusions of ketamine (an N-methyl-D-aspartate receptor inhibitor) have also been correlated with reduced pain scores and a decrease in analgesic requirements postoperatively. Lastly, magnesium (acting through modification of the action of N-methyl-D-aspartate receptors) is another agent, which, as an adjuvant to general anesthesia may improve postoperative recovery and pain control through inhibition of cardiovascular response, reduction in general anesthetic needs, enhanced analgesia and anti-inflammatory response.

There is insufficient data in literature investigating the effect of combinations of these agents intraoperatively. It would be of interest to demonstrate whether the administration of combinations of infusions can lead to enhanced postoperative recovery, an improved opioid-sparing effect and a decrease in the development of chronic pain as compared to the administration of a sole agent alone. Therefore, the aim of this study will be to investigate the effect of a combination of intravenous infusions of lidocaine and magnesium versus a combination of intravenous infusions of lidocaine and ketamine versus an intravenous infusion of lidocaine alone on recovery profile, quality of recovery and postoperative pain after elective gynecological surgery.

Eligibility Criteria:
Inclusion Criteria:

* adult female patients
* American Society of Anesthesiologists (ASA) classification I-II
* elective open gynecological surgery

Exclusion Criteria:

* body mass index (BMI) \>35 kg/m2
* contraindications to local anesthetic administration or non-steroidal agents administration
* systematic use of analgesic agents preoperatively
* chronic pain syndromes preoperatively
* neurological or psychiatric disease on treatment
* pregnancy
* severe hepatic or renal disease
* history of cardiovascular diseases/ arrhythmias/ conduction abnormalities
* drug or alcohol abuse
* language or communication barriers
* lack of informed consent