The Effect of Lidocaine to Prevent the Development of Chronic Post-Surgical Pain

After approval from Northwestern University's IRB, female subjects undergoing urologic, gynecologic or breast surgery will be included in the study. Informed consent will be obtained from all participants. Subject will be randomized using a computer generated table of random numbers into two groups: Group L will receive a 1.5 mg/kg bolus of intravenous lidocaine followed by a 2mg/kg/hr infusion that will be started at the time of surgical induction and will be discontinued one hour after the end of the surgical procedure. Group P will receive the same amount of saline in the same fashion. This dose regimen of systemic lidocaine chosen in the current study has been consistently associated with a reduction of acute postoperative pain.4 There will be no visual characteristic differences between any of the infusions studied and they will all be labeled as a study drug. Patients will receive a standard anesthetic regimen consisting of propofol, fentanyl, succinylcholine, and sevoflurane. Patients will receive ondansetron 4mg and dexamethasone 4 mg to prevent postoperative nausea and vomiting. They will also receive 10 mcg/kg of hydromorphone at the end of surgery to prevent postoperative pain. In the PACU, patients will receive additional doses of hydromorphone to keep pain <4/10 (on a scale where 0 means no pain and 10 is the worst pain possible). On PACU discharge, patients will receive a patient-controlled IV hydromorphone analgesia pump set at 0.2mg IV bolus, no basal infusion and a lockout time of 15 minutes. The intraoperative and postoperative data (pain scores, opioid consumption, side effects) will be collected by a research assistant blinded to the group allocation). Other data collection variables include : Preoperative (Age, BMI, ethnicity, comorbidities, preoperative medication(s), psychiatric disease, pain in the operative area, pain at other locations), Intraoperative (description of surgical procedure, surgical duration, surgical procedure on nerve areas, preservation of the nerves in the operative area nerve, indication for the surgical procedure, intraoperative opioids dose, and Postoperative pain instruments (evaluation of early pain, twenty four hour opioid consumption, drugs and other treatments used in the postoperative period.

QOR 40 questionnaire will be completed by the participant at 24 hours after surgery if they have not been discharged from the hospital. If they have been discharged, the research assistant will contact the participant by telephone to complete the questionnaire.

Patients will be evaluated for the presence and severity of chronic pain as well as the quality of life impact of pain at baseline, three and six months after surgery using a validated instrument in accordance with the IMMPACT recommendations to assess chronic pain and its impact on the patient's quality of life (Brief pain Inventory).8 To characterize the chronic pain, both the short form McGill pain questionnaire and the Modified LANNS scale will be also administered at three and six months.9,10 If there is no response to the 3 month questionnaire, the subject will be contacted by telephone to complete the questionnaire.

Subjects who are experiencing suicidal ideation will be referred to Northwestern Memorial Hospital Emergency Department. The primary care surgeon will also be notified by the principal investigator. Mood will be assessed using the Beck Depression Inventory.14