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

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Hospital for Special Surgery, New York
ClinicalTrials.gov Identifier:
NCT01701115
First received: September 24, 2012
Last updated: January 29, 2014
Last verified: January 2014
  Purpose

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.


Condition Intervention
Shoulder Arthroscopy
Interscalene Block
Procedure: Low Dose (20 ml) Local Anesthetic Volume for Interscalene Block
Procedure: Control Dose (40 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)

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Effect of Local Anesthetic Dose on Interscalene Block for Shoulder Arthroscopy, Patient Satisfaction and Return of Handgrip Strength

Resource links provided by NLM:


Further study details as provided by Hospital for Special Surgery, New York:

Primary Outcome Measures:
  • Handgrip Strength [ Time Frame: A one time assessment pre-operatively in the holding area and each hour (every hour up until 180 minutes) post-operatively in the PACU until patient discharge ] [ Designated as safety issue: No ]
    The primary outcome will be handgrip strength as measured by a dynamometer. A reading will be obtained at baseline (before the interscalene block), upon arrival to the PACU, every 60 minutes after entering the PACU and one reading immediately prior to patient discharge. Two measurements will be taken bilaterally at each time point.


Secondary Outcome Measures:
  • Patient Readiness to Discharge [ Time Frame: Participants will be followed every 15 minutes from entry into the PACU until discharge from the hospital up to 180 minutes post PACU arrival. ] [ Designated as safety issue: No ]

    Patient readiness to discharge- Evaluated every 15 minutes using the PADDS discharge criteria.

    1. BP and pulse within 20% of preoperative baseline
    2. Steady gait, no dizziness, or meets preoperative level
    3. Minimal nausea and vomiting: successfully treated with PO medication
    4. The patient should have minimal or no pain
    5. Postoperative bleeding should be consistent with expected blood loss for the procedure

  • Success of the Block [ Time Frame: 10 minutes post block induction in the Operating Room ] [ Designated as safety issue: No ]
    Evaluated by the level of sedation necessary and the surgeon rating of the block. The block will be considered a success if the sedation did not exceed fentanyl 100mcg or propofol 80mcg/kg/min, and the surgeon rated the block as successful with no patient movement or acceptable with minimal patient movement. Conversion to general anesthesia will also be considered a block failure.

  • Patient Satisfaction [ Time Frame: POD 2 - 3 (48-72 hours after the surgical procedure) ] [ Designated as safety issue: No ]
    Patient satisfaction will be evaluated using an online survey. If the patient does not complete the survey in 2 days following discharge, the patient will receive a phone call and the survey will be completed over the phone. While the survey is not a validated measurement of patient satisfaction, it has successfully been used at our institution for other research projects (IRB # 11100).

  • Side Effects [ Time Frame: Duration of stay in the PACU ] [ Designated as safety issue: No ]

    Side effects will also be evaluated by the blinded research assistant

    1. Hoarseness- The patient will subjectively state whether they sound hoarse
    2. Horners- Will be evaluated post-operatively in the PACU


Estimated Enrollment: 154
Study Start Date: August 2012
Study Completion Date: August 2013
Primary Completion Date: August 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Low Dose (20 mL) Local Anesthetic
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.
Procedure: Low Dose (20 ml) Local Anesthetic Volume for Interscalene Block

Anesthetic volume:

Investigational group: A 1:1 Mepivacaine 1.5%: Bupivacaine 0.5% mixture for a total of 20 mL

Drug: Low Dose (20 mL) Local Anesthetic (Mepivacaine:Bupivacaine)
Other Names:
  • Mepivacaine
  • Bupivacaine
Active Comparator: Control Dose (40 mL) Local Anesthetic
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
Procedure: Control Dose (40 mL) Local Anesthetic Volume for Interscalene Block

Anesthetic volume:

Control group: A 1:1 Mepivacaine 1.5%: Bupivacaine 0.5% mixture for a total of 40 mL

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

Detailed 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.

  Eligibility

Ages Eligible for Study:   18 Years to 80 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

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
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01701115

Locations
United States, New York
Hospital for Special Surgery
New York, New York, United States, 10021
Sponsors and Collaborators
Hospital for Special Surgery, New York
  More Information

No publications provided

Responsible Party: Hospital for Special Surgery, New York
ClinicalTrials.gov Identifier: NCT01701115     History of Changes
Other Study ID Numbers: 2012-011
Study First Received: September 24, 2012
Last Updated: January 29, 2014
Health Authority: United States: Institutional Review Board

Keywords provided by Hospital for Special Surgery, New York:
Interscalene Block

Additional relevant MeSH terms:
Anesthetics, Local
Bupivacaine
Mepivacaine
Anesthetics
Central Nervous System Depressants
Physiological Effects of Drugs
Pharmacologic Actions
Sensory System Agents
Peripheral Nervous System Agents
Central Nervous System Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on July 24, 2014