Morros 2009.

Methods	RCT, parallel design
Participants	129 ASA I ‐ II patients scheduled for elective orthopaedic surgery of elbow, forearm, wrist or finger Exclusion criteria: patient refusal, neurological disturbance, infection/inflammation of the upper extremity, coagulopathy, inability to communicate, those expected to have an axillary catheter
Interventions	Ultrasound with nerve stimulation (n = 65) versus nerve stimulation only (n = 62) Axillary brachial plexus block of median, musculocutaneous, cubital and radial nerve Each nerve blocked with 10 ml 1% mepivacaine (40 ml in total) in each group Ultrasound: 5 ‐ 10 MHz linear probe (Titan, Sonosite) out‐of‐plane approach, once brachial plexus structures seen nerve stimulator used Nerve stimulation (Stimuplex): pulse duration 0.3 msec, Freq 2 Hz; endpoint ‐ stimulation of motor response at 0.4 mA
Outcomes	Adequacy of motor and sensory block (defined as those given only nerve block) Supplementation rate (need for sedation) Time to perform block
Notes	2 anaesthesiologists with extensive experience in both techniques
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Use of random number table
Allocation concealment (selection bias)	Unclear risk	No details given
Blinding of participants and personnel (performance bias):adequacy of block, need for supplementation	High risk	Not possible to blind anaesthetist
Blinding of participants and personnel (performance bias): time outcomes	High risk	Not possible to blind anaesthetist
Blinding of outcome assessment (detection bias): adequacy of block, supplementation of block	Unclear risk	No details of who assessed outcomes
Blinding of outcome assessment (detection bias): time outcomes	Unclear risk	No details of who assessed outcomes
Incomplete outcome data (attrition bias) All outcomes	Low risk	No apparent losses
Selective reporting (reporting bias)	Unclear risk	Published protocol not sought
Baseline characteristics	Low risk	Age, gender, weight, height, ASA status reported. All comparable
Funding sources	Low risk	None apparent
Operator expertise	Unclear risk	Two anaesthesiologists with extensive experience in both techniques