Injection Pressure & Adductor Canal Block

The Impact of Injection Pressure During Adductor Canal Nerve Block

This is a prospective, randomized, single-blinded human clinical trial that will examine how injection pressure influences the spread of a given volume of injectate in the adductor canal, during adductor canal nerve block.

Study Overview

• Status: Terminated
• Conditions: Injury of Anterior Cruciate Ligament; Orthopedic Disorders
• Intervention / Treatment: Procedure: High Pressure Injection; Procedure: Low Pressure Injection

Detailed Description

This is a prospective, randomized, single-blinded human clinical trial that will examine how injection pressure influences the spread of a given volume of injectate in the adductor canal, during adductor canal nerve block. The study population will be patients undergoing elective anterior cruciate ligament repair in the distal lower extremity and receiving preoperative adductor canal nerve blocks for postoperative analgesia. They will be randomized into two groups of 25 patients each. The investigators speculate that high injection pressures (>20 psi) will lead to greater spread of local anesthetic than low injection pressures (<15 psi) during mid-thigh adductor canal nerve blocks. The primary endpoint is the spread of injectate, defined as the distance between the uppermost and lowermost limits of spread of local anesthetic as assessed by ultrasound. The secondary endpoints are the incidence of femoral and sciatic nerve blocks 30 minutes after block placement, amount of IV opioid administered intraoperatively and postoperatively, preoperative and postoperative pain (Numeric Rating Scale, 0-10), and postoperative physical therapy milestone achievement.

• Study Type: Interventional
• Enrollment (Actual): 26
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Florida
    • Miami, Florida, United States, 33136
      • University of Miami Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion criteria:

1. Planned general anesthetic.
2. American Society of Anesthesia classes I, II, or III.
3. Patients aged 18-65.
4. English-speaking patients.

Exclusion criteria:

1. ASA classes IV and V.
2. Patients younger than 18 or older than 65.
3. Contraindication to regional anesthesia (coagulopathy, patient refusal).
4. Allergy to local anesthetic or other study medications.
5. BMI > 35 kg/m2.
6. Chronic opioid use (daily or almost daily use for > 3 months).
7. Active illicit drug use.
8. Additional surgical site other than the limb for adductor canal block.
9. Pregnancy.
10. Preexisting neuropathy in the operative limb.
11. Inability to communicate to investigators or hospital staff.
12. Inability to speak or understand English.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: High Pressure; High pressure injection of Ropivacaine local anesthetic at greater than 20 psi	Procedure: High Pressure Injection; Adductor canal block performed at greater than 20 psi injection pressure
Active Comparator: Low Pressure; Low pressure injection of Ropivacaine local anesthetic at less than 15 psi	Procedure: Low Pressure Injection; Adductor canal block performed at less than 15 psi injection pressure

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Spread of Injectate	Our primary endpoint is the spread of injectate, defined as the distance between the uppermost and lowermost limits of spread of local anesthetic as assessed by ultrasound.	Immediate post-procedure on day 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Events of Femoral Nerve Block 30 Minutes After Block Placement	Sensory testing will use a pinprick method in the femoral (anterior thigh), saphenous (medial calf proximal to the medial malleolus, top of the patella) and sciatic (posterolateral calf, plantar surface of the foot) nerve distributions; if patients are unable to feel the stimulus in the femoral nerve distribution, then an outcome of a femoral nerve block will be recorded.	post-procedure and postoperative on day 1
Number of Events of Sciatic Nerve Block 30 Minutes After Block Placement	Sensory testing will use a pinprick method in the femoral (anterior thigh), saphenous (medial calf proximal to the medial malleolus, top of the patella) and sciatic (posterolateral calf, plantar surface of the foot) nerve distributions; if patients are unable to feel the stimulus in the sciatic nerve distribution, then an outcome of a sciatic nerve block will be recorded.	post-procedure and postoperative on day 1
Postoperative Pain Scores (Numeric Rating Scale, 0-10)	Patients will rate their pain after surgery on a scale from 0-10, with 0 being no pain, and 10 being the worst pain of their life.	postoperative on day 1
Postoperative Physical Therapy Milestone Achievement	The patient will be evaluated by physical therapy postoperatively using the Lower Extremity Function Scale (LEFS). The LEFS is a self-reporting measure (0-80 score range, where 0 is complete disability and 80 is fully functional).	postoperative week 1
Postoperative Physical Therapy Milestone Achievement	The patient will be evaluated by physical therapy postoperatively using the Lower Extremity Function Scale (LEFS). The LEFS is a self-reporting measure (0-80 score range, where 0 is complete disability and 80 is fully functional).	postoperative week 2
Postoperative Physical Therapy Milestone Achievement	The patient will be evaluated by physical therapy postoperatively using the Lower Extremity Function Scale (LEFS). The LEFS is a self-reporting measure (0-80 score range, where 0 is complete disability and 80 is fully functional).	postoperative week 3
Postoperative Physical Therapy Milestone Achievement	The patient will be evaluated by physical therapy postoperatively using the Lower Extremity Function Scale (LEFS). The LEFS is a self-reporting measure (0-80 score range, where 0 is complete disability and 80 is fully functional).	postoperative week 4
Opioid Administration	Intraoperative and immediate postoperative opioid administration. Calculated as morphine milliequivalent (in milligrams).	day 1

Collaborators and Investigators

• Sponsor: University of Miami
• Investigators: Principal Investigator: Andres Missair, MD, University of Miami

Study record dates

Study Major Dates

• Study Start (Actual): December 3, 2015
• Primary Completion (Actual): November 9, 2016
• Study Completion (Actual): December 9, 2016

Study Registration Dates

• First Submitted: September 25, 2015
• First Submitted That Met QC Criteria: September 28, 2015
• First Posted (Estimate): September 30, 2015

Study Record Updates

• Last Update Posted (Actual): January 13, 2020
• Last Update Submitted That Met QC Criteria: January 6, 2020
• Last Verified: January 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Wounds and Injuries; Leg Injuries; Knee Injuries; Anterior Cruciate Ligament Injuries; Musculoskeletal Diseases
• Other Study ID Numbers: 20150583

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO