Effect of Local Anesthetic Dose on Interscalene Block (Low Dose ISB)

Hospital for Special Surgery (HSS)

Status: Completed

Conditions: Shoulder Arthroscopy; Interscalene Block

Treatments: Procedure: Low Dose (20 ml) Local Anesthetic Volume for Interscalene Block; Drug: Low Dose (20 mL) Local Anesthetic (Mepivacaine:Bupivacaine); Drug: Control Dose (40 mL) Local Anesthetic (Mepivacaine:Bupivacaine); Procedure: Control Dose (40 mL) Local Anesthetic Volume for Interscalene Block

Study type: Interventional

Funder types: Other

Identifiers

NCT01701115

2012-011

Details and patient eligibility

About

The purpose of this study is to determine if a decrease in the standard volume of local anesthetic used to numb your shoulder area before shoulder arthroscopy will provide adequate anesthesia for the procedure and decrease the amount of time until you are ready for discharge from the hospital.

Full description

Traditionally, an interscalene block is done either with nerve stimulator or ultrasound guided using 40-60mL of local anesthetic. The study plans to investigate the difference in hand grip strength post-operatively in patients who will receive interscalene blocks with 40mL versus a lower dose (20mL) of local anesthetic. We suspect the lower dose will achieve adequate surgical anesthesia while creating less motor block and thus, increase patient satisfaction, present fewer complications or adverse affects and decrease time in the recovery room.

Enrollment: 154 patients

Sex: All

Ages: 18 to 80 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Age: 18 - 80 years old
• Surgical time < 2.5 hours
• ASA I, II or III
• Shoulder arthroscopy

Exclusion criteria

• Age < 18 or > 80 years old
• Chronic pain patients (on narcotics/opioids > 3 months)
• Open shoulder surgical procedure
• BMI > 40
• Pre-existing neurological condition
• Patient refusal of interscalene block
• Severe respiratory disease or hemidiaphragmatic dysfunction
• Allergy to any local anesthetics
• Planned general anesthesia

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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154 participants in 2 patient groups

Low Dose (20 mL) Local Anesthetic

Experimental group

Description:

Intervention to be administered is a total volume of 20 mL local anesthetic containing a 1:1 mixture of 1.5% Mepivacaine: 0.5% Bupivacaine.

Treatment:

Procedure: Low Dose (20 ml) Local Anesthetic Volume for Interscalene Block

Drug: Low Dose (20 mL) Local Anesthetic (Mepivacaine:Bupivacaine)

Control Dose (40 mL) Local Anesthetic

Active Comparator group

Description:

Intervention to be administered is a total volume of 40 mL local anesthetic containing a 1:1 mixture of 1.5% Mepivacaine: 0.5% Bupivacaine

Treatment:

Procedure: Control Dose (40 mL) Local Anesthetic Volume for Interscalene Block

Drug: Control Dose (40 mL) Local Anesthetic (Mepivacaine:Bupivacaine)