Continuous Transversus Abdominis Plane Nerve Blocks: Relative Effects of a Basal Infusion vs. Repeated Bolus Doses (A Randomized, Double-Masked, Active-Control, Split-Body, Crossover Study)
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
- Sensory Deficit (Cold Roller), Mid-axillary Line
研究概览
简要总结
Single-injection transversus abdominis plane (TAP) blocks have been used to treat postoperative pain, and are become very popular within the United States because of their high analgesic potency and relative ease of placement. Unfortunately, the longest local anesthetic available lasts only 8-12 hours. Continuous TAP blocks-also termed "perineural infusion"-involve bathing the multiple nerves of the abdominal wall in local anesthetic using a percutaneously-inserted perineural catheter inserted just anterior (ventral) and cephalad to the anterior superior iliac spine. For most catheter locations, an infusion is preferred to a single-injection nerve block because the duration of analgesia may be extended to better match the duration of surgical pain. But, unlike brachial plexus, femoral, and sciatic nerve perineural infusion, a continuous basal infusion of local anesthetic does not provide adequate analgesia for TAP catheters. This may be due to the fact that the TAP is a relatively tight space, so it might require a bolus of fluid to adequately spread the perineural local anesthetic to the multiple required nerves (as evidence of this, single-injection TAP blocks are very effective, although with a limited duration). The result is that while single-injection TAP blocks are widely used, TAP catheters have not been adopted. This scenario leaves surgical pain untreated following the resolution of the single-injection TAP block. The recent development of an infusion pump that can automatically deliver repeated bolus doses may allow the spread of local anesthetic to the multiple sensory nerves necessary to provide adequate analgesia, with a duration that better matches postoperative requirements. The investigators therefore propose a randomized, double-masked, controlled trial to determine if delivering local anesthetic as a repeated bolus dose results in improved local anesthetic spread/effects compared with a continuous basal infusion for TAP catheters.
详细描述
This investigation will be a randomized, observer-masked, controlled, split-body, human-subjects clinical trial. Of note, the investigators 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.
Volunteers will be solicited using the CTRI Research Match and an existing database of volunteers (IRB approved). If a volunteer meets inclusion/exclusion criteria (see Eligibility Criteria) and desires study participation, written, informed consent will be obtained using a UCSD IRB-approved/stamped ICF. 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.
Perineural catheter insertion: Following written, informed consent, subjects will be admitted to the UCSD CTRI Center for Clinical Research Services (CCR) 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). Bilateral TAP perineural catheters (FlexBlock, Teleflex Medical, Reading, PA, USA) will be inserted using ultrasound guidance using a technique previously described. To check the perineural catheter placement accuracy, 5 mL of normal saline will be administered via the catheters under ultrasound guidance with the definition of a successful catheter insertion an increase in fluid volume within the TAP (the plane between the transversus abdominis muscle and internal oblique muscle). Inaccurately inserted catheters will be replaced.
Treatment Group Assignment: Subjects will act as their own controls: the right side will be randomized to one of two treatment groups: ropivacaine 0.2% administration as either a basal infusion (8 mL/h) or bolus doses (24 mL administered every 3 hours). The left side will receive the other possible treatment. Randomization will be based on computer-generated codes. Randomization will be in blocks of four. An infusion pump with study infusate will be attached to each of the perineural catheters and initiated at Hour 0. Which side of the participant's body will receive the basal rate and which side will receive bolus volume will depend upon the treatment group assignment but the total dose of local anesthetic is the same for each side.
The tubing from the pumps to the subjects will be gently wound at least 5 rotations and covered with opaque tape, masking which perineural catheter is receiving which treatment (ropivacaine is clear, so the flow through the clear tubing from the tape to the perineural catheters will not be visually distinguishable).
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
- •healthy volunteers weighing more than 45 kg;
- •must be willing to have bilateral transverses abdominis plane nerve block catheters be placed with subsequent ropivacaine administration and sensory testing for 6 hours
排除标准
- •BMI greater than 40 (BMI=weight in kg/ [height in meters];
- •regular opioid use within the previous 2 months;
- •previous participation within the same study;
- •allergy to study medications;
- •known renal insufficiency (creatinine > 1.5 mg/dL);
- •incarceration; and
- •any known neuro-muscular deficit of either abdominal wall.
研究组 & 干预措施
RIGHT side BOLUS and left side basal
Bilateral transversus abdominis catheters were inserted and ropivacaine 0.2% administered concurrently. For the right catheter, the ropivacaine was administered as two separate bolus doses of 24 mL each: one at time point zero and one 3 hours later. For the left catheter, the ropivacaine was administered as a continuous basal infusion (8 mL/h) from time point zero for the following 6 hours
干预措施: Bolus (Drug)
RIGHT side BOLUS and left side basal
Bilateral transversus abdominis catheters were inserted and ropivacaine 0.2% administered concurrently. For the right catheter, the ropivacaine was administered as two separate bolus doses of 24 mL each: one at time point zero and one 3 hours later. For the left catheter, the ropivacaine was administered as a continuous basal infusion (8 mL/h) from time point zero for the following 6 hours
干预措施: Basal (Drug)
RIGHT side BASAL and left side bolus
Bilateral transversus abdominis 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 6 hours. For the left catheter, the ropivacaine was administered as two separate bolus doses of 24 mL each: one at time point zero and one 3 hours later
干预措施: Bolus (Drug)
RIGHT side BASAL and left side bolus
Bilateral transversus abdominis 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 6 hours. For the left catheter, the ropivacaine was administered as two separate bolus doses of 24 mL each: one at time point zero and one 3 hours later
干预措施: Basal (Drug)
结局指标
主要结局
Sensory Deficit (Cold Roller), Mid-axillary Line
时间窗: 6 hours following the initiation of local anesthetic administration
The distance of sensory deficit to cold measured in centimeters along the mid-axillary line. A cold roller is a device that looks like a paint application roller, but the roller itself is metal that can be brought to freezing. It is placed in the mid-axillary line and moved up and down until the sensory deficit to cold is revealed and subsequently measured.
次要结局
- Sensory Deficit (Cold Roller), Mid-axillary Line(Hourly from Hours 0-5 following the initiation of local anesthetic administration)
- Sensory Deficit (Von Frey Hairs), Mid-axillary Line(Hourly from Hours 0-6 following the initiation of local anesthetic administration)
- Sensory Deficit (Cold Roller), Transverse Horizontal Line(Hourly from Hours 0-6 following the initiation of local anesthetic administration)
- Sensory Deficit (Von Frey Hairs), Transverse Horizontal Line(Hourly from Hours 0-6 following the initiation of local anesthetic administration)
研究者
Brian M. Ilfeld, MD, MS
Professor of Anesthesiology, In Residence
University of California, San Diego