Clinical Effects of Individualized Spinal Anesthesia Dosing Based on Ultrasound-Measured Dural Sac Cross-Sectional Area in Patients Undergoing Transurethral Resection of the Prostate: A Prospective, Randomized Controlled Trial
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 60
- 试验地点
- 1
- 主要终点
- Incidence of Intraoperative Hypotension
研究概览
简要总结
This randomized controlled study will evaluate whether individualizing the dose of spinal anesthesia according to the ultrasound-derived dural sac cross-sectional area (DSCSA) can improve hemodynamic stability in patients undergoing transurethral resection of the prostate (TURP).
Participants aged 40 years or older will be randomly assigned to one of two groups. In the individualized-dose group, the anteroposterior diameter of the dural sac will be measured by ultrasound at the L3-L4 level, and DSCSA will be calculated from this measurement. The dose of intrathecal bupivacaine will then be individualized according to the calculated DSCSA. In the control group, participants will receive a fixed dose of intrathecal bupivacaine. Both groups will also receive intrathecal fentanyl.
The main outcome is the incidence of intraoperative hypotension. The study will also evaluate the number of hypotensive episodes, minimum mean arterial pressure, vasopressor and atropine requirements, sensory and motor block characteristics, respiratory monitoring parameters, cerebral oxygenation, and adverse events.
The study aims to determine whether a DSCSA-guided dosing strategy can reduce excessive spinal block and improve hemodynamic stability while maintaining effective spinal anesthesia.
详细描述
This prospective, randomized controlled study compares two routinely used approaches to determining the intrathecal bupivacaine dose for spinal anesthesia in patients undergoing transurethral resection of the prostate (TURP). No new drug, new indication, or experimental treatment will be introduced. Both dosing approaches are currently used in routine clinical practice; the study will prospectively and randomly compare their clinical effects.
Participants will be randomly assigned to either a dural sac cross-sectional area (DSCSA)-guided individualized dosing group or a fixed-dose control group.
Before spinal anesthesia, the anteroposterior diameter of the dural sac will be measured by ultrasound at the L3-L4 intervertebral level. DSCSA will be calculated using the formula A = π × (D/2)².
In the individualized-dose group, a DSCSA of 150 mm² will be used as the reference value corresponding to 10 mg of intrathecal bupivacaine. The bupivacaine dose will be adjusted proportionally according to the participant's calculated DSCSA and limited to a minimum of 6 mg and a maximum of 12.5 mg. Fentanyl 25 micrograms will be added intrathecally.
In the fixed-dose group, participants will receive 10 mg (2 mL of 0.5%) intrathecal bupivacaine together with fentanyl 25 micrograms.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Supportive Care
- 盲法
- Double (Participant, Outcomes Assessor)
盲法说明
Participants and outcome assessors will be blinded to group allocation. The clinician performing spinal anesthesia will follow the assigned dosing protocol and therefore will not be blinded to the intervention.
入排标准
- 年龄范围
- 40 Years 至 —（Adult, Older Adult）
- 性别
- Male
- 接受健康志愿者
- 否
入选标准
- •Male participants aged 40 years or older
- •American Society of Anesthesiologists (ASA) physical status I-III
- •Scheduled to undergo transurethral resection of the prostate (TURP) for prostate cancer
排除标准
- •Refusal of spinal anesthesia
- •Local infection or wound at the planned puncture site
- •Current anticoagulant therapy
- •Neurological disease, including multiple sclerosis, myelopathy, or peripheral neuropathy
- •Known allergy to any of the study medications
- •Inability to maintain the required position during ultrasound measurement or spinal puncture
研究组 & 干预措施
DSCSA-Guided Individualized Dose
The dural sac cross-sectional area (DSCSA) will be estimated from the ultrasound-measured anteroposterior dural sac diameter at the L3-L4 level. The intrathecal bupivacaine dose will be individualized according to the DSCSA, using 150 mm² as the reference area corresponding to 10 mg bupivacaine. The calculated bupivacaine dose will be limited to 6-12.5 mg. Fentanyl 25 micrograms will also be administered intrathecally.
干预措施: DSCSA-Guided Individualized Spinal Anesthesia Dosing (Procedure)
DSCSA-Guided Individualized Dose
The dural sac cross-sectional area (DSCSA) will be estimated from the ultrasound-measured anteroposterior dural sac diameter at the L3-L4 level. The intrathecal bupivacaine dose will be individualized according to the DSCSA, using 150 mm² as the reference area corresponding to 10 mg bupivacaine. The calculated bupivacaine dose will be limited to 6-12.5 mg. Fentanyl 25 micrograms will also be administered intrathecally.
干预措施: Fentanyl (FEN) (Drug)
Fixed Dose
Participants will receive a fixed intrathecal dose of 10 mg (2 mL of 0.5%) bupivacaine together with fentanyl 25 micrograms.
干预措施: Fentanyl (FEN) (Drug)
DSCSA-Guided Individualized Dose
The dural sac cross-sectional area (DSCSA) will be estimated from the ultrasound-measured anteroposterior dural sac diameter at the L3-L4 level. The intrathecal bupivacaine dose will be individualized according to the DSCSA, using 150 mm² as the reference area corresponding to 10 mg bupivacaine. The calculated bupivacaine dose will be limited to 6-12.5 mg. Fentanyl 25 micrograms will also be administered intrathecally.
干预措施: Bupivacaine (Drug)
Fixed Dose
Participants will receive a fixed intrathecal dose of 10 mg (2 mL of 0.5%) bupivacaine together with fentanyl 25 micrograms.
干预措施: Bupivacaine (Drug)
结局指标
主要结局
Incidence of Intraoperative Hypotension
时间窗: During surgery (from completion of spinal anesthesia until the end of surgery)
Intraoperative hypotension is defined as a decrease in mean arterial pressure (MAP) of ≥20% from baseline or an MAP \<65 mmHg. Participants meeting either criterion at least once during surgery will be classified as having intraoperative hypotension. The outcome will be reported as the percentage of participants with intraoperative hypotension.
次要结局
- Number of Intraoperative Hypotension Episodes(During surgery (from completion of spinal anesthesia until the end of surgery))
- Minimum Intraoperative Mean Arterial Pressure(During surgery (from completion of spinal anesthesia until the end of surgery))
- Percentage of Participants With a ≥30% Decrease in Mean Arterial Pressure(During surgery (from completion of spinal anesthesia until the end of surgery))
- Percentage of Participants Requiring Ephedrine(During surgery (from completion of spinal anesthesia until the end of surgery))
- Total Ephedrine Dose(During surgery (from completion of spinal anesthesia until the end of surgery))
- Percentage of Participants Requiring Atropine(During surgery (from completion of spinal anesthesia until the end of surgery))
- Total Atropine Dose(During surgery (from completion of spinal anesthesia until the end of surgery))
- Maximum Sensory Block Level(During surgery (from completion of spinal anesthesia until the end of surgery))
- Time to Achieve T10 Sensory Block(Up to 30 minutes after spinal anesthesia)
- Time to Two-Dermatome Sensory Regression(From maximum sensory block until two-dermatome regression, assessed up to 3 hours after spinal anesthesia)
- Time to Recovery to Modified Bromage Score 0(From completion of spinal anesthesia until recovery to Modified Bromage score 0, assessed up to 3 hours after spinal anesthesia)
- Number of Integrated Pulmonary Index ≤4 Episodes(During surgery (from completion of spinal anesthesia until the end of surgery))
- Incidence of Adverse Events(During surgery (from completion of spinal anesthesia until the end of surgery))
研究者
Ezgi Budak Ozyalcın
Specialist in Anesthesiology and Reanimation
Istanbul University - Cerrahpasa