Cui 2010.

Methods	Randomized, placebo‐controlled trial. Participants, personnel, and outcome assessors were blinded. This study evaluated the effects of systemic administration of lidocaine on postoperative pain and morphine requirements after propofol‐remifentanil‐based anaesthesia in patients undergoing thoracic surgery. The study was conducted in China from 1 January to 31 July 2008.
Participants	Number assessed for eligibility: N/A Number randomized: 45 → 22:23 Number analysed: 20:20 Inclusion criteria Patients (18 to 65 years) undergoing thoracic surgery of at least 3 to 6 hrs, ASA I to II Exclusion criteria Chronic pain, analgesics or opioids 7 days before surgery, drug or alcohol abuse, psychiatric disorder or obesity, cardiovascular disorder, central nervous disease they could communicate with the investigator, contraindications to propofol, opioids, and lidocaine; they had contraindications to the self‐administration of morphine (PCA device), their intra‐operative time lasted more than 6 hrs or their immediate extubation was not planned after surgery. Baseline details Experimental group (n = 20) Mean age (years): 54 M = 65%, F = 35% Mean weight (kg): 65 ASA I/II: 6:14 Mean duration of anaesthesia (min): 244 Main surgical procedures (n): pulmonary lobectomy (7), oesophagectomy (9), cardiectomy (4) Control group (n = 20) Mean age (years): 40 M = 0%, F = 100% Mean weight (kg): 55 ASA I/II: N/A Mean duration of anaesthesia (min): 288 Main surgical procedures (n): pulmonary lobectomy (6), oesophagectomy (9), cardiectomy (5)
Interventions	Experimantal group (20 patients) No bolus; lidocaine was given as a continuous infusion (33 µg/kg/min) from induction of anaesthesia until skin closure. Control group (20 patients) The control group received the same volume normal saline.
Outcomes	Dichotomous Side effects (drowsiness, metal taste, perioral numbness, visual disturbances) Continuous Pain score on coughing (VAS 0 to 10) at 6 hrs Morphine requirement during PACU at 30, 30 to 60 min, and 0 to 120 min after extubation and PCA morphine consumption on the ward at 2 to 6 hrs, 6 to 48 hrs, and total morphine consumption 0 to 48 hrs (data presented as median with IQR)
Notes	Small trial sample size (< 200 patients) No sample size calculation reported Medication "During the preoperative anaesthetic evaluation, patients were instructed in the use of the PCA pump, the four‐point verbal rating scale (VRS‐4, 0 = no pain, 1 = slight pain, 2 = moderate pain, 3 = intense or severe pain) and the 100 mm VAS for pain (from 0 = no pain to 100 = worst pain), and were premedicated with 10 mg diazepam orally on the evening before surgery. Postoperative pain was treated with morphine. At the patient’s demand, boluses of morphine (1.0 to 2.0 mg, 2 min intervals) were given to keep the VRS‐4 score less than 2 and Riker’s sedation–agitation status less than 5 during the period immediately after general anaesthesia. Subsequently, 2 hrs after tracheal extubation, patients were connected to a PCA device set to deliver 1.0 mg morphine as an intravenous bolus with a 5min lockout interval, and this PCA regimen was continued for 48 hrs after completion of surgery." Anaesthesia The anaesthesia regime was standardized in both groups. Funding "The present work was supported by the following grants: Clinical‐Basic Medicine Cooperation Fund of Capital Medical University, Research Fund of the Beijing Friendship Hospital, National Natural Science Foundation of China (30670782 and 30871219), Beijing Natural Science Foundation (5072008), Key Scientific Developing Programme of Beijing Municipal Commission of Education (KZ200810025012), Beijing Municipal Programme for Hundred‐Thousand‐Ten Thousand Excellent Talents of the New Century (Li J), and the Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality (PHR200906116)."
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "…a random‐number table was generated to specify the group each patient would be assigned upon entry into the trial."
Allocation concealment (selection bias)	Unclear risk	Quote: "...envelope containing the group assignment was prepared." Not clear if envelopes were sequentially numbered, sealed and opaque.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "…a nurse who was not involved in the patient’s evaluation opened the envelope and prepared remifentanil, lidocaine and physiological saline solution syringes." Quote: "the investigators involved in patient management or data collection were not aware of the group assignment."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "the investigators involved in patient management or data collection were not aware of the group assignment."
Incomplete outcome data (attrition bias) All outcomes	Low risk	Dropout rate (experimental/control): 9%:13% Quote: "...five patients were excluded from this research (three in the control group and two in the lidocaine group) because the duration of the operation exceeded 6 hrs."
Selective reporting (reporting bias)	Unclear risk	There is no reference to a trial registry and no published study protocol.
Other bias	Low risk	The study appears to be free of other sources of bias.