Continuous Adductor Canal Nerve Blocks: Relative Effects of a Basal Infusion v. Hourly Bolus Doses
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 24
- 试验地点
- 1
- 主要终点
- Tolerance to Cutaneous Electrical Current
研究概览
简要总结
Patients usually experience moderate-to-severe pain following the knee replacement that is often treated with a femoral nerve block (injection of numbing medicine placed around the main nerve of the knee joint). To make the nerve block last longer, a tiny tube is often placed next to the nerve and numbing medicine is infused for multiple days. However, while the numbing medicine takes away pain, it also decreases sensations, muscle strength, and proprioception (knowing where the leg is in space without looking at it) which greatly increases the risk of falling. Since falling can be catastrophic following major surgery, a femoral nerve blocks are being phased out by surgeons and anesthesiologists. The most-promising replacement is called an adductor canal nerve block. For this new type of block, a perineural catheter is inserted into a small canal in the middle of the upper leg. This canal contains the sensory nerve fibers leading to the knee, and only a single nerve that serves a relatively small muscle. Multiple studies have demonstrated a dramatic increase in muscle strength using the new adductor canal block compared with the traditional femoral block. However, practitioners perceptions of the new block is that it provides insufficient pain control following knee arthroplasty, even though all of the sensory nerves affected with the femoral block are also-theoretically-affected with the adductor canal block. One reason for this difference may be the small canal of the latter which is a relatively tight area in which the numbing medicine might not spread particularly well (due to pressure from surrounding tissues). One way to possibly counter this issue is by providing repeated boluses of the numbing medicine that will improve the medicine's spread relative to a more-traditional slow, continuous ("basal") infusion. This study seeks to compare these two techniques of medication administration through perineural adductor canal catheters:
Our primary aim is to test the hypothesis that, for continuous adductor canal blocks, providing local anesthetic as repeated, hourly bolus doses results in an increased sensory block compared with providing local anesthetic as a continuous basal infusion at an equivalent hourly dose.
As a secondary aim, we hypothesize that, for continuous adductor canal blocks, providing local anesthetic as repeated, hourly bolus doses results in either equivalent or less motor block compared with providing local anesthetic as a continuous basal infusion at an equivalent hourly dose.
详细描述
This investigation will be a randomized, observer-masked, controlled, split-body, human-subjects clinical trial. Of note, we will be using standard-of-care local anesthetics under their FDA approved purpose and do not plan to research a possible change of indication or use of these drugs as part of this research project.
Enrollment. Subjects will be volunteers of both sexes, age 18 and older. Volunteers will be solicited using newspaper advertisements, fliers, the CTRI Research Match, and an existing database of volunteers (IRB approved). If a volunteer meets inclusion/exclusion criteria and desires study participation, written, informed consent will be obtained. Selection for inclusion will not be based on race or socioeconomic status. The study population of interest includes men and women of all races and socioeconomic status. A urine pregnancy test will be administered to all women of childbearing age following written informed consent but before any study interventions. This urine test will be administered by CTRI nursing staff using standard, FDA-approved urine pregnancy testing devices.
Inclusion and Exclusion Criteria. See section #10 below.
Perineural catheter insertion. Following written, informed consent, subjects will be admitted to the UCSD CTRI Center for Clinical Research Services (CCR) inpatient unit and have demographic/morphometric data recorded (e.g., age, weight, height). An intravenous line will be placed in an upper extremity, followed by external monitors (pulse oximeter, blood pressure, and EKG), and oxygen by nasal cannula. Sedation will be provided with intravenous fentanyl (50 μg) and/or midazolam (1 mg), or oral valium (10 mg) and/or dilaudid (4 mg), as necessary. Subjects will then have bilateral adductor canal perineural catheters placed using standard UC San Diego techniques.
Treatment Group Assignment. Subjects will act as their own controls: The dominant side (left or right) will be randomized to one of two treatment groups: ropivacaine 0.2% administration as either a basal infusion (8 mL/h) or bolus doses (8 mL administered hourly). The non-dominant contralateral side will receive the other possible treatment. Randomization will be based on computer-generated codes. Randomization will be in blocks of two, and stratified by sex. An infusion pump with study infusate will be attached to each of the perineural catheters and initiated at Hour 0. The basal rate and bolus volume will depend upon the treatment group (note that the basal rate and bolus volume differ for each treatment group, but the total dose of local anesthetic is the same for each):
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
盲法说明
The only individual aware of the treatment group assignments is the investigational pharmacist who has no interaction with the study subjects. Treatment group assignments were released by the investigational pharmacy only after completion of data collection.
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •(1) age ≥ 18 years; and (2) willing to have bilateral adductor canal perineural catheters placed with subsequent ropivacaine administration and motor/sensory testing for 14 hours, requiring an overnight stay in the UCSD CTRI-CCR to allow dissipation of local anesthetic infusion effects by the following morning.
排除标准
- •(1) current daily analgesic use; (2) opioid use within the previous 4 weeks; (3) any neuro-muscular deficit of either femoral nerves and/or quadriceps muscles; (4) morbid obesity [weight > 35 kg/m2]; (5) pregnancy (as determined by a urine pregnancy test prior to any study interventions); and (6) incarceration. We expect to recruit a maximum of 30 healthy volunteers; with a target goal of 24 for the analysis. Selection for inclusion will not be based on gender, race, or socioeconomic status. The study population of interest includes men and women of all races and socioeconomic status. There will be no participants from vulnerable populations, such as pregnant women, children, or prisoners.
研究组 & 干预措施
RIGHT side BOLUS and left side basal
Bilateral adductor canal catheters were inserted and ropivacaine 0.2% administered concurrently. For the right catheter, the ropivacaine was administered as hourly bolus doses of 8 mL each a total of 8 times: one at time point zero and 1 on the hour for the following 7 hours. For the left catheter, the ropivacaine was administered as a continuous basal infusion (8 mL/h) from time point zero for the following 8 hours
干预措施: Bolus (Drug)
RIGHT side BOLUS and left side basal
Bilateral adductor canal catheters were inserted and ropivacaine 0.2% administered concurrently. For the right catheter, the ropivacaine was administered as hourly bolus doses of 8 mL each a total of 8 times: one at time point zero and 1 on the hour for the following 7 hours. For the left catheter, the ropivacaine was administered as a continuous basal infusion (8 mL/h) from time point zero for the following 8 hours
干预措施: Basal (Drug)
RIGHT side BASAL and left side bolus
Bilateral adductor canal catheters were inserted and ropivacaine 0.2% administered concurrently. For the right catheter, the ropivacaine was administered as a continuous basal infusion (8 mL/h) from time point zero for the following 8 hours. For the left catheter, the ropivacaine was administered as hourly bolus doses of 8 mL each a total of 8 times: one at time point zero and 1 on the hour for the following 7 hours.
干预措施: Bolus (Drug)
RIGHT side BASAL and left side bolus
Bilateral adductor canal catheters were inserted and ropivacaine 0.2% administered concurrently. For the right catheter, the ropivacaine was administered as a continuous basal infusion (8 mL/h) from time point zero for the following 8 hours. For the left catheter, the ropivacaine was administered as hourly bolus doses of 8 mL each a total of 8 times: one at time point zero and 1 on the hour for the following 7 hours.
干预措施: Basal (Drug)
结局指标
主要结局
Tolerance to Cutaneous Electrical Current
时间窗: After 8 h of infusion
Evaluated in the seated position using transcutaneous electrical stimulation (TES) in the same manner as described throughout the anesthesia literature (this is a "gold standard" for regional anesthesia studies). EKG pads will be positioned over the proximal patella and quadriceps tendon 1 cm medial of midline and attached to a nerve stimulator. The current will be increased from 0 mA until the subject reports slight discomfort (or, up to a maximum of 80 mA), at which time the current is recorded as the TES value and the nerve stimulator turned off.
次要结局
- Tolerance to Transcutaneous Electrical Current(baseline through Hour 14 (except Hour 8 which is the primary outcome) and then again at Hour 22)
- Maximum Voluntary Isometric Contraction of the Quadriceps(Baseline and then every hour through Hour 14, as well as Hour 22)
研究者
Brian M. Ilfeld, MD, MS
Professor of Anesthesiology, In Residence
University of California, San Diego