NCT02607488.

Trial name or title	Perioperative systemic lidocaine for enhanced bowel recovery after bariatric surgery: a dose dependent study
Methods	Randomized, double‐blinded, controlled trial. The aim of this study is to investigate whether perioperative administration of low rather than high intravenous infusion rates of lidocaine can achieve early postoperative restoration of bowel motility at lower plasma levels. The study is conducted in Egypt.
Participants	Estimated enrolment: 180 Inclusion criteria 18 years to 65 years, obese patients with a body mass index equal or greater than 35 kg/m2, ASA II and III, patients scheduled for laparoscopic bariatric surgery under general anaesthesia Exclusion criteria History of significant cardiac, respiratory, hepatic, renal disease, history of an atrioventricular block grade II to III, long QT‐syndrome, pre‐existing disorder of the gastrointestinal tract, patients with history of alcohol or drug abuse, allergy to amide local anaesthetics, history of epilepsy, pregnancy, patients receiving cardiovascular medications, steroids or patients receiving opioid analgesic medication within 24 hours before the operation, conversion from a laparoscopic to an open laparotomy
Interventions	Experimental (lidocaine 1%) Participants will receive an intravenous bolus of 0.1 mL/kg of lidocaine 1.5% solution followed by a continuous infusion 0.1 mL/kg/h of lidocaine 1% solution which will be continued for 24 hours after surgery. Experimental (lidocaine 1.5%) Participants will receive an intravenous bolus of 0.1 mL/kg of lidocaine 1.5% solution followed by a continuous infusion 0.1 mL/kg/h of lidocaine 1.5% solution which will be continued for 24 hours after surgery. Experimental (lidocaine 2%) Participants will receive an intravenous bolus of 0.1 mL/kg of lidocaine 1.5% solution followed by a continuous infusion 0.1 mL/kg/h of lidocaine 2% solution which will be continued for 24 hours after surgery. Control Participants will receive an intravenous bolus of 0.1 mL/kg of saline 0.9% solution followed by a continuous infusion 0.1 mL/kg/h of Saline 0.9% which will be continued for 24 hours after surgery. All medications in the study protocol will be based on the dosing body weight (IBW + 0.4 × (actual body weight−IBW).
Outcomes	Primary outcome Postoperative recovery of bowel function (times to first passage of flatus, first defecation, and tolerating liquids measured in hours from the end of surgery) Secondary outcomes Perioperative changes in heart rate (heart rate will be recorded before induction of anaesthesia, 5 mins after induction, every 15 mins intraoperatively, and then 1 h, 4 h, 12 h, 24 h, 36 h, 48 h after surgery) Perioperative changes in blood pressure (blood pressure will be recorded before induction of anaesthesia, 5 mins after induction, every 15 mins intraoperatively, and then 1 h, 4 h, 12 h, 24 h, 36 h, 48 h after surgery) Pain scores (four‐hourly pain scores at rest and during movement and cough) Intraoperative total use of fentanyl Perioperative use of intravenous fluids Perioperative use of norepinephrine Perioperative use of dobutamine The balance between the fluid intake and output Postoperative cumulative morphine use Times to clinical recovery (times to spontaneous breathing, eye opening, obeying verbal commands, and extubation) Length of postanaesthesia care unit stay Time to readiness for hospital Time to actual discharge from hospital Perioperative changes in cognitive function (mini mental score preoperatively (baseline) and 24 h and 48 h after surgery Overall patient satisfaction score Postoperative nausea and vomiting Postoperative pruritus Postoperative sedation Number of participants with surgery‐related complications (occurrence of bleeding, fever, wound dehiscence, wound infection, anastomotic leak, abscess, peritonitis, infection) Associated comorbidities (preoperative diabetes, renal impairment, hepatic dysfunction, cardiac dysfunction, pulmonary disease, endocrine disease) Number of participants with lidocaine treatment‐related adverse events (arrhythmia, sedation, nausea and vomiting, light‐headedness, headache, perioral numbness, tunnel vision, or seizures) Serum lidocaine level Plasma albumin level
Starting date	The study started in November 2015 (currently recruiting)
Contact information	Mohamed R El Tahan, MD, mohamedrefaateltahan@yahoo.com; Samah El Kenany, MD, sk_20022000@yahoo.com
Notes	N/A