Plasma Kinetics of Levobupivacaine After Transversus Abdominis Plane (TAP) Block in Abdominal Surgery: A Prospective Study and Definition of a Safety Window for Intravenous Lidocaine Administration
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 26
- 主要终点
- Maximum Plasma Levobupivacaine Concentration (Cmax)
研究概览
简要总结
This prospective single-center observational pharmacokinetic study will evaluate plasma levobupivacaine concentrations after ultrasound-guided transversus abdominis plane (TAP) block in adult patients undergoing elective abdominal surgery under general anesthesia at CHU Liège. Participants receiving TAP block as part of standard clinical care (levobupivacaine 0.375%, total volume 40 mL, maximum dose 150 mg) will undergo serial blood sampling at 3, 7, 15, 30, 60, 120, and 180 minutes after block completion. Plasma levobupivacaine concentrations will be measured using validated LC-MS/MS methods. The primary objectives are to estimate maximum plasma concentration (Cmax) and time to maximum concentration (Tmax). Secondary objectives include characterization of the concentration-time profile, AUC0-180, interindividual variability, and exploratory associations with clinical factors (age, sex, BMI, type of surgery). The study also aims to inform a pragmatic safety window for subsequent intravenous lidocaine infusion used in multimodal analgesia protocols. Approximately 26 participants will be enrolled. No modification of routine anesthesia or analgesic care is required apart from study-related blood sampling.
详细描述
This prospective single-center pharmacokinetic observational study is designed to characterize systemic exposure to levobupivacaine after ultrasound-guided transversus abdominis plane (TAP) block performed as part of routine perioperative analgesia for elective abdominal surgery under general anesthesia.
TAP block is widely integrated into multimodal analgesic pathways because it may reduce postoperative pain and opioid requirements. However, administration of relatively large volumes of local anesthetic into fascial planes can result in measurable systemic absorption. Although levobupivacaine has a favorable safety profile compared with racemic bupivacaine, understanding peak plasma concentrations and their timing remains clinically relevant, particularly when additional analgesic strategies such as intravenous lidocaine may be considered during the perioperative period.
Eligible adult participants scheduled for abdominal surgery and already planned to receive TAP block according to institutional practice will be enrolled after informed consent. No changes to standard anesthetic or surgical management are mandated by the study. The TAP block will be performed by experienced anesthesiologists using the institutional standard technique with levobupivacaine 0.375% (total volume 40 mL; maximum dose 150 mg).
The reference time (T0) will be defined as completion of local anesthetic injection. Serial blood samples will be obtained during the early postoperative period at predefined time points up to 180 minutes after T0 to capture the expected absorption phase and early elimination profile. Plasma levobupivacaine concentrations will be quantified using a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay.
The primary pharmacokinetic parameters of interest are maximum observed plasma concentration (Cmax) and time to maximum concentration (Tmax). Secondary analyses will include concentration-time profiles, area under the curve from 0 to 180 minutes (AUC0-180), interindividual variability, and exploratory evaluation of associations between exposure metrics and selected demographic or clinical variables such as age, body mass index, sex, and surgical category.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 75 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age ≥18 years
- •Scheduled elective abdominal surgery under general anesthesia
- •Planned ultrasound-guided TAP block as part of standard perioperative analgesic care
- •Able to understand and speak French sufficiently to understand the study information and consent form
- •Able and willing to provide written informed consent
排除标准
- •Refusal or inability to provide informed consent
- •Known allergy or hypersensitivity to amide local anesthetics
- •Severe hepatic impairment
- •Renal impairment (estimated glomerular filtration rate <50 mL/min/1.73 m²)
- •Contraindication to repeated blood sampling or inability to complete the sampling schedule
- •Participation in another clinical study that could affect absorption, distribution, metabolism, or elimination of local anesthetics
- •Pregnancy
- •Emergency surgery or life-threatening urgent condition
- •Immediate postoperative instability requiring intensive care transfer (e.g., hemodynamic instability)
- •Inability to understand French sufficiently for study information and consent
- •Persons requiring special legal protection for consent (e.g., minors, guardianship, incapacity to consent)
研究组 & 干预措施
TAP Block Pharmacokinetic Cohort
Adult participants undergoing elective abdominal surgery under general anesthesia at CHU Liège who receive an ultrasound-guided transversus abdominis plane (TAP) block with levobupivacaine 0.375% (total volume 40 mL; maximum dose 150 mg) as part of standard perioperative analgesic management. This is a single observational cohort. The intervention of interest is the routine TAP block, after which serial blood samples are collected up to 180 minutes to characterize plasma levobupivacaine pharmacokinetics. No experimental treatment is assigned by the study.
干预措施: Ultrasound-Guided Transversus Abdominis Plane Block with Levobupivacaine (Procedure)
结局指标
主要结局
Maximum Plasma Levobupivacaine Concentration (Cmax)
时间窗: From completion of TAP block (T0) to 180 minutes post-block placement
Maximum observed plasma concentration (Cmax, µg/mL) of levobupivacaine after TAP block, determined from serial plasma samples collected during the first 180 minutes after completion of the block.
Time to Maximum Plasma Levobupivacaine Concentration (Tmax)
时间窗: From completion of TAP block (T0) to 180 minutes post-block placement
Time to maximum observed plasma concentration (Tmax, minutes) of levobupivacaine after TAP block, determined from serial plasma samples collected during the first 180 minutes after completion of the block.
次要结局
- Area Under the Plasma Concentration-Time Curve From 0 to 180 Minutes (AUC0-180) of Levobupivacaine(From completion of TAP block (T0) to 180 minutes post-block placement)
- Plasma Levobupivacaine Concentration at Each Sampling Time Point(From completion of TAP block (T0) to 180 minutes post-block placement.)
- Interindividual Variability of Maximum Plasma Levobupivacaine Concentration (Cmax)(From completion of TAP block (T0) to 180 minutes post-block placement)
- Association Between Area Under the Plasma Concentration-Time Curve (AUC0-180) and Clinical Factors(From completion of TAP block (T0) to 180 minutes post-block placement)
- Time to Reach Plasma Levobupivacaine Concentration Below Prespecified Safety Threshold(From completion of TAP block (T0) to 180 minutes post-block placement)
- Interindividual Variability of Area Under the Plasma Concentration-Time Curve (AUC0-180)(From completion of TAP block (T0) to 180 minutes post-block placement)
研究者
Michele Carella
Clinical Professor
University of Liege