Addition of Clonidine to Ropivacaine in Adductor Canal Block

NCT ID: NCT03057015

Last Updated: 2018-05-03

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: PHASE4
• Total Enrollment: 80 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2017-05-22
• Study Completion Date: 2019-02-28

Brief Summary

Total knee arthroplasty (knee replacement) is a common orthopedic procedure for osteoarthritis. This procedure is performed either under general anesthesia or spinal anesthesia; after the procedure in the recovery room, these patients undergo adductor canal block, which is a nerve block to provide 8-14 hours of postoperative pain control. For this nerve block, 15-20 ml of local anesthetic is combined with adjuvant medications to improve the quality of pain control as well as the duration of pain relief. The primary local anesthetic used for adductor canal block is ropivacaine, and the commonly used adjuvants are epinephrine and dexamethasone.

There is conflicting data available in the literature regarding efficacy of addition of clonidine to the local anesthetic injection in peripheral nerve blocks, and there is no data assessing the efficacy of this medication in adductor canal blocks.

Once the consent process is completed, patients are enrolled in two arms. Upon conclusion of surgery, a sealed and coded envelope with either clonidine or the placebo syringe will be given to the acute pain service staff performing the nerve block. This will be mixed with local anesthetic solution and injected in the adductor canal under ultrasound guidance.

The primary outcome measure will be the duration of analgesia, which will be assessed as the time interval between placement of adductor canal block to the first request of opioid analgesic by patients (which will be obtained from hospital electronic medical records). Secondary outcomes will include:

1. Duration of sensory block, which will be assessed as the time interval between injection of local anesthetic and report of postoperative pain of 3 or more on an 11 point scale (0=no pain; 10= worst pain imaginable) by the patient (this will be assessed every 4 hours).

2. Duration of motor block, which will be assessed as the time interval between the onset of motor block to complete recovery of motor block by assessing straight leg raise strength (this will be assessed every 4 hours).

3. Cumulative 24 and 48 hour opioid analgesic use.

4. Post-block pain scores, evaluated by an 11 point pain score (0-10), which will be done every 15 minutes for the first hour after surgery and every 4 hours thereafter for 24 hours.

Conditions

Postoperative Pain

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: QUADRUPLE

Study Groups

Clonidine

50 mcg clonidine + 0.5% ropivacaine + 2 mg dexamethasone + 5 mcg/ml epinephrine in 20 ml solution

Group Type: EXPERIMENTAL

Clonidine

Intervention Type: DRUG

50 mcg Clonidine added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in the treatment group.

Ropivacaine

Intervention Type: DRUG

Clonidine or Placebo added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in both treatment and placebo groups.

Dexamethasone

Intervention Type: DRUG

Clonidine or Placebo added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in both treatment and placebo groups.

Epinephrine

Intervention Type: DRUG

Clonidine or Placebo added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in both treatment and placebo groups.

Placebo

0.5 ml normal saline + 0.5% ropivacaine + 2 mg dexamethasone + 5 mcg/ml epinephrine in 20 ml solution

Group Type: PLACEBO_COMPARATOR

Placebo

Intervention Type: DRUG

Normal saline added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in the placebo group.

Ropivacaine

Intervention Type: DRUG

Clonidine or Placebo added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in both treatment and placebo groups.

Dexamethasone

Intervention Type: DRUG

Clonidine or Placebo added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in both treatment and placebo groups.

Epinephrine

Intervention Type: DRUG

Clonidine or Placebo added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in both treatment and placebo groups.

Interventions

Clonidine

50 mcg Clonidine added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in the treatment group.

Intervention Type: DRUG

Placebo

Normal saline added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in the placebo group.

Intervention Type: DRUG

Ropivacaine

Clonidine or Placebo added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in both treatment and placebo groups.

Intervention Type: DRUG

Dexamethasone

Clonidine or Placebo added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in both treatment and placebo groups.

Intervention Type: DRUG

Epinephrine

Clonidine or Placebo added to the solution of 0.5% ropivacaine, 2 mg dexamethasone and 5 mcg/ml epinephrine for adductor canal block-present in both treatment and placebo groups.

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

• Men and women ages 18 and older
• ASA physical status classification system I, II and III (healthy patient or patient with mild to moderate systemic disease)
• Patient coming in for elective total knee arthroplasty under general or neuraxial anesthesia and postoperative adductor canal block
• Patients staying for at least 24 hrs post operatively
• Patients who provide informed consent
• Patients presenting for surgery >1 hour in length and <6 hours.

Exclusion Criteria

• History of recent common colds, upper respiratory infections or immune deficiencies
• Patients allergic to clonidine
• Pregnant women (all women of childbearing age undergo pregnancy testing prior to anesthesia as per UVMMC peri-operative protocol)
• Patients who are already on chronic clonidine therapy for management of blood pressure
• Patients on chronic opioid therapy defined as more than 10 mg of oxycodone per day (or equivalent doses of other opioid analgesics)

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Vermont

OTHER

Sponsor Role: lead

Responsible Party

Borzoo Farhang

Clinical Instructor of Anesthesiology

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Borzoo Farhang, DO

Role: PRINCIPAL_INVESTIGATOR

University of Vermont Medical Center

Locations

University of Vermont Medical Center

Burlington, Vermont, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Borzoo Farhang, DO

Role: CONTACT

borzoo.farhang@uvmhealth.org

8028819927

Facility Contacts

Borzoo Farhang, DO

Role: primary

borzoo.farhang@uvmhealth.org

802-881-9927

Other Identifiers

CHRMS 17-0107

Identifier Type: -

Identifier Source: org_study_id