Sherif 2017.

Methods	Randomized, controlled trial. No statement on blinding. Postoperative pain control for morbidly obese patients represents a challenge because of their sensitivity towards opioid‐induced respiratory depression. We elected both dexmedetomidine and xylocaine (lidocaine) continuous infusions as adjuvants because they lack respiratory depression side effect. It is not stated where the study was conducted. Date not specified. Trial identifier: N/A
Participants	Sample size: 150 (3 groups, n = 50, respectively) Only two groups are of interest for this review. Inclusion criteria Patients with ASA physical status Exclusion criteria N/A
Interventions	Experimental group (N/A patients) Lidocaine 2 mg/kg bolus over 10 minutes followed by 1.5 mg/kg/h continuous infusion during the whole operation period Control group (N/A patients) Saline in a similar manner (control group)
Outcomes	The total morphine consumption was designed to be the primary outcome variable, pain score, and QoR‐40 was set as secondary outcome variables. Pain score was measured by NRS, while the QoR score was estimated by the QoR‐40 questionnaire
Notes	Small trial sample size (< 200 patients) Anaesthesia N/A Funding N/A Notes Only abstract available