Grigoras 2012

Methods	Triple‐blind (participants, providers, outcome assessors) randomized controlled study Sequence generation by computer‐generated codes Follow‐up: 3 months
Participants	36 participants at Cork University Hospital in Cork, Ireland Operation: mastectomy or wide local excision + axillary node dissection, including sentinel node 2 groups, size: 17/19, all women Age (± SD): 55.9 (± 10.4), 56.8 (± 14.4)
Interventions	Group 1 (lidocaine group): immediately after intubation, IV bolus lidocaine (1.5 mg/kg in 10 min) followed by continuous IV infusion (1.5 mg/kg/h), stopped 60 min after skin closure. Group 2 (control group): immediately after intubation, IV bolus saline followed by continuous IV infusion of saline, stopped 60 min after skin closure. Neither group received preanaesthetic medication. Both groups had the same GA protocol, including propofol and fentanyl for induction, sevoflurane and nitrous oxide in O2 for maintenance. The remaining analgesic regimen was identical between groups, including intraoperative paracetamol 1 g and diclofenac 75 mg IV with morphine as needed and postoperative morphine PCA (1 mg max every 5 min), diclofenac (50 mg oral/rectal every 12 h as needed), paracetamol (1 g oral/rectal every 6 h as needed), tramadol (100 mg IM/oral as needed as rescue) Adjuvants: none Immediate post‐op pain control: improved
Outcomes	Dichotomous: pain/no pain at 3 months Continuous: short form McGill Pain Questionnaire (SF‐MPQ) at 3 months Other reported outcomes: measurement of area of peri‐incisional hyperalgesia, pain catastrophizing scale at 3 months post‐op (broken down by question), Hosptial Anxiety and Depression scale at 3 months post‐op
Notes	Funding Sources: source of funding not stated Conflicts of interest: "the authors declare no conflict of interest."
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "patients were randomly allocated to 1 of 2 groups based on computer generated codes"
Allocation concealment (selection bias)	Low risk	Codes were, quote: "maintained in sequentially numbered opaque envelopes"
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "on the morning of surgery an anaesthetist who was not involved in the patient’s evaluation opened the envelope and prepared either 1% lidocaine or normal saline in coded 50mL syringes. None of the investigators involved in patient management or data collection were aware of the group assignment...The anaesthetist, surgeon, and nursing staff were all blinded to the group allocations"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote:"a dedicated investigator, unaware of the patients’ group assignment" performed the outcome assessments. "None of the investigators involved in patient management or data collection were aware of the group assignment".
Incomplete outcome data (attrition bias) All outcomes	Low risk	There were no dropouts; all participants randomized were included in the final analysis at 3 months.
Selective reporting (reporting bias)	Low risk	A post‐hoc analysis of preoperative factors comparing participants who did and those who did not develop persistent postsurgical pain was done, but this was specified. The rest of listed outcomes were all reported.
Null bias	Low risk	Quote: "VAS pain scores at rest, 4 hours postoperatively were less in lidocaine group compared with control group"