Comparative Efficacy and Dose-Response of Intrathecal Dexmedetomidine in Attenuating Post-Spinal Shivering: Double-Blinded Randomized Controlled Trial
试验速览
- 阶段
- 3 期
- 状态
- 尚未招募
- 入组人数
- 120
- 试验地点
- 1
- 主要终点
- Incidence of clinically significant shivering
研究概览
简要总结
Dexmedetomidine, a highly selective α2-adrenergic agonist, when used intrathecally as an adjuvant to local anesthetics, prolongs sensory/motor block and may blunt thermoregulatory shivering mechanisms. Several randomized controlled trials and meta-analyses have demonstrated decreased shivering incidence with intrathecal dexmedetomidine, but reported doses vary (commonly 2.5, 5, and 10 µg, and in some trials up to 15-20 µg), and the balance between efficacy and adverse effects (sedation, bradycardia, and hypotension) is not fully established. Hence, a head-to-head randomized comparison of several low-to-moderate intrathecal doses is warranted.
Objective: to compare the safety and efficacy of three intrathecal dexmedetomidine doses (2.5 µg, 5 µg, 10 µg) versus placebo for the prevention of post-spinal shivering.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- Double (Participant, Outcomes Assessor)
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
- •Adult patients (age 18-75 years)
- •Scheduled for ureteric stone removal surgery
- •ASA(American Society of Anesthesiologists) physical status I, II, or III
- •Able to provide informed consent
排除标准
- •Known allergy to dexmedetomidine, bupivacaine, or other study medications
- •Preexisting bradycardia (heart rate <50 beats per minute)
- •Second- or third-degree atrioventricular (AV) block without a pacemaker
- •Severe hepatic dysfunction
- •Uncontrolled hypotension
- •Pregnancy
- •Chronic use of α₂-agonists or antagonists (e.g., clonidine, tizanidine)
- •Infection at the planned spinal puncture site
- •Coagulopathy or bleeding disorder
- •Inability to rate or communicate shivering (e.g., language barrier, cognitive impairment)
研究组 & 干预措施
Group P
Patients in this group will receive the standard spinal anesthetic consisting of hyperbaric bupivacaine 0.5% (15 mg) combined with an equivalent volume of normal saline (0.9% NaCl), containing no active dexmedetomidine. The total intrathecal injection volume will be standardized to 3.5 mL across all groups by adjusting the volume of saline added.
干预措施: Group P (Placebo Control Group) (Drug)
Group D2.5
Patients in this group will receive the standard spinal anesthetic (15 mg hyperbaric bupivacaine 0.5%) supplemented with a low dose of 2.5 µg of dexmedetomidine. Normal saline will be added to achieve the standardized total intrathecal volume of 3.5 mL.
干预措施: Group D2.5 (Low-Dose Dexmedetomidine Group) (Drug)
Group D5
Patients in this group will receive the standard spinal anesthetic combined with a moderate dose of 5 µg of dexmedetomidine. The total volume will be adjusted to 3.5 mL with normal saline.
干预措施: Group D5 (Moderate-Dose Dexmedetomidine Group) (Drug)
Group D10
Patients in this group will receive the standard spinal anesthetic supplemented with a higher dose of 10 µg of dexmedetomidine, with normal saline used to standardize the total volume to 3.5 mL.
干预措施: Group D10 (Higher-Dose Dexmedetomidine Group) (Drug)
结局指标
主要结局
Incidence of clinically significant shivering
时间窗: Throughout the intraoperative period until 60 minutes post-spinal.
Incidence of clinically significant shivering within 60 minutes after spinal injection, defined as Crossley and Mahajan shivering scale grade ≥2 (scale 0-4)The highest intensity of shivering experienced by the patient, scored on the 0-4 scale. The Crossley and Mahajan shivering scale is a clinically validated, four-grade ordinal scale (0-4) used to objectively quantify the severity of post-anesthetic shivering. It is defined as follows: Grade 0 signifies no shivering; Grade 1 indicates mild, intermittent fasciculations of the face, neck, or chest; Grade 2 represents visible, intermittent shivering involving more than one muscle group; Grade 3 denotes generalized, continuous shivering of the whole body; and Grade 4 describes gross, bed-shaking tremors that interfere with monitoring or procedure. Grade ≥2 is typically considered clinically significant and often triggers therapeutic intervention. The scale is assessed through direct visual observation of the patient by trained personnel.
次要结局
- Time to first shivering episode(Intraoperative period, up to 60 minutes post-spinal.)
- Requirement of rescue anti-shivering drug(Intraoperative period, as needed.)
- Dose of rescue anti-shivering drug(Intraoperative period, as needed.)
- Patient satisfaction(Postoperatively (e.g., prior to discharge from PACU).)
- Sedation level(Postoperative 24 hour)
- Time to first analgesic request(24 hours Postoperatively.)
研究者
Neveen Abd El Maksoad Kohaf
Lecturer of Clinical Pharmacy
Al-Azhar University