Skip to main content
. 2016 Feb 18;2016(2):CD007874. doi: 10.1002/14651858.CD007874.pub2

Kim 2013a.

Methods Double‐blind randomized controlled trial
Participants Age (years, mean ± SD): Group C = 38.32 ± 15.73, Group L = 35.52 ± 15.57, Group N = 41.86 ± 15.67, Group LN = 47.26 ± 13.97
Gender (M:F): Group C = 25:25, Group L = 20:30, Group N = 29:21, Group LN = 20:30
Inclusion criteria: Age 18 years to 68 years old, ASA I‐II, undergoing elective surgery
Exclusion criteria: if patients met any of the following criteria: the regular use of sedatives or analgesics; an allergy to lidocaine; a pre‐existing movement disorder; pre‐existing drug abuse; inability to co‐operate or give informed consent; any anticipated difficulty in obtaining an airway; thrombophlebitis (or any other pain‐causing lesion); the presence of chronic obstructive pulmonary disease (COPD); or any contraindication to the administration of N2O (e.g. pneumothorax
Recruitment: 205 adult patients randomly assigned (200 were analysed)
Setting: Korea
Interventions Pretreatment with venous occlusion
A total of 205 adult patients received one of the following combinations:
NaCl and 100% O2 (Group C; n = 50);
0.5 mg/kg pretreated lidocaine and 100 % O2 (Group L; n = 50);
NaCl and a mixture of 67% N2O/O2 (Group N; n = 50);
0.5 mg/kg lidocaine and a mixture of 67% N2O/O2 (Group LN; n = 50).
Vein occlusion was released after 1 min, and 5 ml propofol was injected over 10 sec. The remainder of the induction dose of propofol (with a 3 ml bolus of normal saline and 0.6 mg/kg rocuronium) was then injected. The response to the rocuronium injection was assessed with a 4‐point scale (0–3)
Outcomes Pain intensity assessed on 11‐point scale using a 0‐10, visually enlarged, laminated, Numeric Rating Scale
Outcomes reported and used
  1. Incidence of pain

  2. Adverse effects


Outcomes sought but not reported
  1. Incidence of high‐intensity pain

  2. Patient satisfaction


Outcomes reported but not used
  1. Mean of pain intensity

Notes Period of the study: dates not reported
Risk of bias
Bias Authors' judgement Support for judgement
Random sequence generation (selection bias) Low risk A computer‐generated randomization table
Allocation concealment (selection bias) Unclear risk N/A
Blinding of participants and personnel (performance bias) 
 All outcomes Unclear risk N/A
Blinding of outcome assessment (detection bias) 
 All outcomes Low risk "The investigator recording the pain scores was blinded to the drugs given and to the gas mixture administered to the patients."
Incomplete outcome data (attrition bias) 
 All outcomes Low risk "A total of 205 patients were initially recruited into the study. Three patients were excluded because of difficulty with venous cannulation on the dorsum of the hand. Two patients in group N could not complete the study (one developed excitement and laughing and the other was oversedated)."
Selective reporting (reporting bias) Unclear risk N/A
Other bias Low risk The study appears to be free of other sources of bias