SUPraclavicular Regional Anaesthesia affecting Bispectral Index™? as Level Of Consciousness monitor (SUPRABLOC): a Pilot Randomised Controlled trial

The Effect of Supraclavicular Brachial Plexus Blockade on Bispectral Index (BIS) in Adults Undergoing Forearm Surgery: a Pilot Randomised Controlled trial

Status

Active, not recruiting

Phases

Phase 2

Study type

Interventional

Source

PACTR

Registry ID

PACTR202110574604922

Enrollment

Registered

2021-10-13

Start date

2019-10-01

Completion date

Unknown

Last updated

2026-08-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Anaesthesia

Interventions

Supraclavicular brachial plexus block with 0.5 percent Bupivacaine

Supraclavicular blockade not administered

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Patients presenting for elective and emergency surgery in orthopaedic theatres. Forearm, wrist and hand surgery.

Exclusion criteria

Exclusion criteria: American Society of Anesthesiologists (ASA) class 3 or more. Not fasted for 6 hours or more pre-operatively. Known allergies to the local anaesthetics used. Signs of peripheral neuropathy or other neurological disorder affecting the limb to be blocked. Failed block or block complications. Contraindication to peripheral nerve block (including bleeding tendencies). Sedation required in the induction room due to anxiousness or any other reason. Known systemic neurological or psychiatric illnesses or receiving neuroleptic medication. Those who received narcotics, anxiolytics or analgesics is the preceding 8 hours. Baseline oxygen saturation on room air less than 94%. Patients less than 18 or more than 65 years of age. Patients whose oxygen saturation decreased to below 94% or whose blood pressure deviated more than 20% from baseline values after receiving the block

Design outcomes

Primary

Measure	Time frame
Primary objectives were formulated to test feasibility of performing a larger trial and included assessment of recruitment, acceptance and completion rates, equipment performance, ease of data collection and simplicity of data collection forms and block success rate. Due to the fact that emphasis should not be placed on the statistical significance of intervention effects in pilot trials, the estimated differences between treatment arms and sample size estimates for formal RCT are included in secondary objectives. Primary objectives included a)Assessment of the proportion of patients that can be included after exclusion criteria, b)Assessment of the rate of patient acceptance or refusal to partake in the study, c)Assessment of the proportion of patients who complete the study, d)Investigating the amount of BIS electrodes that need replacing during the study, e)Assessing the quality of BIS recordings by investigating the proportion of inadequate contact of the adhesive causing non-reading BIS values, f)To assess the ease of completing the data form and ease of data collection as determined by the opinion of the person completing this form and g)To assess the rate of supraclavicular block success. A Priori cut-off values for progression to formal RCT were established as follows, a)The proportion of patients that can be asked to participate in the study after initial screening should ideally be = 50% of patients screened, b)Rate of acceptance to participate in the study should be = 50% of patients approached, c)Study should be completed by = 80% of patients, d)Amount of BIS electrodes that need replacing should be = 15% of total number used, e)Less than 10% total inadequate contact as shown by individual BIS contact drop = 15, f)Opinion of ease of completing the data form = 3 on a scale of 1 to 5 (1= Very difficult, 2= Slightly difficult, 3=Normal difficulty, 4=Relatively easy, 5=Easy), g)Block success rate, as judged by inability to completely flex elbow = 90%.	—

Measure

Time frame

Primary objectives were formulated to test feasibility of performing a larger trial and included assessment of recruitment, acceptance and completion rates, equipment performance, ease of data collection and simplicity of data collection forms and block success rate. Due to the fact that emphasis should not be placed on the statistical significance of intervention effects in pilot trials, the estimated differences between treatment arms and sample size estimates for formal RCT are included in secondary objectives. Primary objectives included a)Assessment of the proportion of patients that can be included after exclusion criteria, b)Assessment of the rate of patient acceptance or refusal to partake in the study, c)Assessment of the proportion of patients who complete the study, d)Investigating the amount of BIS electrodes that need replacing during the study, e)Assessing the quality of BIS recordings by investigating the proportion of inadequate contact of the adhesive causing non-reading BIS values, f)To assess the ease of completing the data form and ease of data collection as determined by the opinion of the person completing this form and g)To assess the rate of supraclavicular block success. A Priori cut-off values for progression to formal RCT were established as follows, a)The proportion of patients that can be asked to participate in the study after initial screening should ideally be = 50% of patients screened, b)Rate of acceptance to participate in the study should be = 50% of patients approached, c)Study should be completed by = 80% of patients, d)Amount of BIS electrodes that need replacing should be = 15% of total number used, e)Less than 10% total inadequate contact as shown by individual BIS contact drop = 15, f)Opinion of ease of completing the data form = 3 on a scale of 1 to 5 (1= Very difficult, 2= Slightly difficult, 3=Normal difficulty, 4=Relatively easy, 5=Easy), g)Block success rate, as judged by inability to completely flex elbow = 90%.

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Secondary

Measure	Time frame
Due to the fact that emphasis should not be placed on the statistical significance of intervention effects in pilot trials, the estimated differences between treatment arms and sample size estimates for formal RCT are included in secondary objectives. Secondary objectives included a)To measure the proportion of patients with BIS values falling below 80 and the difference between treatment arm means in BIS values and b)To gather and generate data from which the sample size of a definitive RCT can be estimated. Criteria for progression to formal RCT were as follows, a)We suggest that the minimum clinically important difference (MCID) between treatment arms should be estimated as a difference in mean BIS value of = 10 and a difference of patients in whom BIS values drop below 80 that is = 20%, b)Sample size for a definitive RCT is to be calculated and judged whether feasible or not. We recommend that sample sizes up to 300 patients in total would be reasonable to execute as a formal RCT.	—

Measure

Time frame

Due to the fact that emphasis should not be placed on the statistical significance of intervention effects in pilot trials, the estimated differences between treatment arms and sample size estimates for formal RCT are included in secondary objectives. Secondary objectives included a)To measure the proportion of patients with BIS values falling below 80 and the difference between treatment arm means in BIS values and b)To gather and generate data from which the sample size of a definitive RCT can be estimated. Criteria for progression to formal RCT were as follows, a)We suggest that the minimum clinically important difference (MCID) between treatment arms should be estimated as a difference in mean BIS value of = 10 and a difference of patients in whom BIS values drop below 80 that is = 20%, b)Sample size for a definitive RCT is to be calculated and judged whether feasible or not. We recommend that sample sizes up to 300 patients in total would be reasonable to execute as a formal RCT.

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Countries

South Africa

Contacts

Public ContactNadeema Williams

Administrative Officer

nadeemaw@sun.ac.za0027219389028

Outcome results

None listed

Source: PACTR (via WHO ICTRP) · Data processed: Aug 9, 2026