Turning the Probe, Changing the View: A Novel Long Axis Approach to the Femoral Artery Block (FAB) for Managing Tourniquet Pain and Hypertension in Below-the-Knee Fracture Surgery: A Prospective, Randomized, Double-Blind Controlled Trial
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 84
- 试验地点
- 1
- 主要终点
- Incidence of tourniquet-induced hypertension
研究概览
简要总结
This is a prospective, randomized, double-blind controlled trial evaluating an ultrasound-guided femoral artery block (FAB) using a long-axis in-plane approach compared with a short-axis approach and a control group.
The study will include adult patients (ASA I-III) undergoing below-the-knee fracture surgery with tourniquet application. All patients will receive standardized anesthesia including sciatic nerve block and total intravenous anesthesia.
Participants will be randomized into three groups: short-axis FAB, long-axis FAB, or control (saline injection). The primary aim is to assess the effectiveness of the long-axis FAB in reducing tourniquet-induced hypertension. Secondary outcomes include hemodynamic stability, analgesic requirements, pain scores, block characteristics, and procedural performance metrics.
详细描述
Tourniquet application during lower limb orthopedic surgery is associated with significant hemodynamic responses, including pain and tourniquet-induced hypertension (TH), which may increase perioperative cardiovascular risk. Femoral artery block (FAB) is a novel ultrasound-guided regional anesthesia technique targeting the perivascular sympathetic plexus surrounding the femoral artery to attenuate these responses.
Previous studies have described FAB using a short-axis in-plane ultrasound approach. This study proposes a novel long-axis in-plane ultrasound technique, hypothesizing that longitudinal visualization of the femoral artery may improve anatomical alignment with perivascular sympathetic structures, resulting in more effective sympathetic blockade, improved safety, and enhanced clinical efficacy.
This is a prospective, randomized, double-blind controlled trial including adult patients (ASA I-III) scheduled for below-the-knee fracture surgery requiring tourniquet application for at least 45 minutes. After informed consent and baseline assessment, patients will be randomized into three groups: (1) short-axis FAB with ropivacaine, (2) long-axis FAB with ropivacaine, and (3) control group receiving normal saline injection.
All patients will receive standardized anesthetic management including sciatic nerve block at the popliteal level and total intravenous anesthesia using propofol and remifentanil via Target-Controlled Infusion (TCI) under BIS monitoring. Hemodynamic variables (blood pressure and heart rate) will be recorded at predefined intraoperative and postoperative time points. Tourniquet-induced hypertension will be defined as a >30% increase in systolic blood pressure from baseline.
Secondary outcomes include intraoperative opioid and vasopressor requirements, incidence of femoral and saphenous nerve spread, procedural performance metrics (imaging and needling time), postoperative pain scores (VAS), and opioid consumption in the recovery unit.
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
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age >18 years
- •Physical status ASA I-III
- •Fluent in Greek or English
- •Scheduled surgery: below-knee fractures
- •Tourniquet duration ≥45 minutes
排除标准
- •Refusal to participate
- •Local inflammation at block site
- •Known allergy to study drugs
- •Morbid obesity (BMI >40)
- •Communication inability
- •Systemic neurological disease affecting peripheral nerves
- •Chronic pain therapy
- •Diabetic neuropathy
- •Uncontrolled hypertension
研究组 & 干预措施
Short-axis femoral artery block
Ultrasound-guided femoral artery block using short-axis in-plane technique with 10 mL ropivacaine 0.5%.
干预措施: Femoral artery block - short-axis (Procedure)
Long-axis femoral artery block
Ultrasound-guided femoral artery block using long-axis in-plane technique with 10 mL ropivacaine 0.5%.
干预措施: Femoral artery block - long-axis (Procedure)
Saline control injection
Ultrasound-guided femoral artery injection using in-plane technique with 10 mL 0.9% normal saline.
干预措施: Normal saline injection (control) (Other)
结局指标
主要结局
Incidence of tourniquet-induced hypertension
时间窗: From tourniquet inflation to 90 minutes intraoperatively
Tourniquet-induced hypertension defined as an increase in systolic blood pressure greater than 30% from baseline values during tourniquet application.
次要结局
- Heart rate(From tourniquet inflation to 90 minutes intraoperatively)
- Intraoperative esmolol consumption(Intraoperative period)
- Intraoperative remifentanil consumption(Intraoperative period)
- Postoperative pain score (VAS)(0-60 minutes postoperative)
- Morphine consumption in recovery unit(0-60 minutes postoperative)
- Femoral nerve block spread(Immediate postoperative period)
- Saphenous nerve block spread(Immediate postoperative period)
- Imaging time(During FAB block procedure)
- Needling time(During FAB block procedure)
- Total block performance time(During FAB block procedure)
研究者
Banasiou Lamprini
Principal Investigator
National and Kapodistrian University of Athens