Analysis of Factors Influencing Epidural Depth in Patients Undergoing Percutaneous Nephrolithotomy and Development of a Predictive Model
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 3,278
- 试验地点
- 1
- 主要终点
- epidural depth
研究概览
简要总结
Accurate estimation of epidural depth is critical for safe epidural anesthesia during percutaneous nephrolithotomy (PCNL). Although various imaging modalities can predict epidural depth, they increase healthcare burden and are not always feasible in emergency or bedside settings. Identifying simple, easily obtainable clinical parameters-such as sex, age, and body mass index (BMI)-for predicting epidural depth has become a research priority. However, systematic investigations specifically targeting the Chinese population remain scarce. This retrospective study aims to identify independent factors influencing epidural depth in PCNL patients and to develop simple, level-specific predictive models for different puncture sites, thereby providing a practical reference for clinical epidural anesthesia.
详细描述
Percutaneous nephrolithotomy (PCNL) is the standard minimally invasive surgical procedure for removal of kidney stones larger than 2 cm and is established as the gold standard for the management of complex renal calculi. This procedure may be performed under either general anesthesia or regional anesthesia, including epidural or spinal anesthesia. Accumulating meta-analyses have demonstrated that, compared with general anesthesia, regional anesthesia is associated with reduced postoperative pain scores and lower total hospital costs, without compromising the stone-free rate. Furthermore, in awake patients undergoing regional anesthesia, respiratory movements may generate a so-called "respiratory-synchronous stone fragmentation effect," which facilitates the expulsion of stone debris.
Successful epidural anesthesia relies critically on accurate identification of the epidural space and precise control of puncture depth. Insufficient puncture depth may result in improper catheter placement and subsequent block failure, whereas excessive puncture depth increases the risk of dural puncture, leading to cerebrospinal fluid leakage and post-dural puncture headache. In severe cases, inadvertent injection of a large dose of local anesthetics into the subarachnoid space can cause life-threatening cardiovascular and respiratory depression. Therefore, preprocedural estimation of the skin-to-epidural space distance is of considerable clinical importance.
Although racial differences in epidural depth have been reported, systematic investigations specifically targeting the Chinese population remain scarce. Various imaging modalities, including computed tomography, magnetic resonance imaging, and ultrasound, can be used to predict epidural depth. However, these examinations increase healthcare burden and are not always feasible in emergency or bedside settings. Consequently, identifying simple, easily obtainable clinical parameters-such as sex, age, and body mass index (BMI)-for predicting epidural depth has become a research priority.
In this context, the present study aimed to identify factors influencing epidural depth through a retrospective analysis of clinical data from PCNL patients and to develop simple, level-specific predictive models for different puncture sites, thereby providing a practical reference for clinical epidural anesthesia.
研究设计
- 研究类型
- Observational
- 观察模型
- Other
- 时间视角
- Retrospective
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
- •Successful epidural puncture and catheter placement using the midline approach
- •Clear documentation of puncture level and puncture depth in the anesthesia record
排除标准
- •Dural puncture during anesthesia (including those who subsequently had a successful repuncture)
- •Use of the paramedian approach for epidural puncture
- •Uncertain epidural anesthesia effect requiring combined general anesthesia
- •Incomplete clinical data
研究组 & 干预措施
T11-T12
On operating room admission, after providing written informed consent for anesthesia, patients underwent standard monitoring (ECG, NIBP, pulse oximetry). Baseline demographic and anthropometric data, including hospital admission ID, sex, height, and weight, were recorded, and body mass index (BMI) was calculated. After positioning in the lateral decubitus position, the T11-T12 interspace was selected for puncture using a midline approach, and the loss-of-resistance technique confirmed epidural space entry. Puncture depth (skin-to-epidural space) was recorded from needle shaft markings to the nearest 0.1 cm.
T12-L1
On operating room admission, after providing written informed consent for anesthesia, patients underwent standard monitoring (ECG, NIBP, pulse oximetry). Baseline demographic and anthropometric data, including hospital admission ID, sex, height, and weight, were recorded, and body mass index (BMI) was calculated. After positioning in the lateral decubitus position, the T12-L1 interspace was selected for puncture using a midline approach, and the loss-of-resistance technique confirmed epidural space entry. Puncture depth (skin-to-epidural space) was recorded from needle shaft markings to the nearest 0.1 cm.
L1-L2
On operating room admission, after providing written informed consent for anesthesia, patients underwent standard monitoring (ECG, NIBP, pulse oximetry). Baseline demographic and anthropometric data, including hospital admission ID, sex, height, and weight, were recorded, and body mass index (BMI) was calculated. After positioning in the lateral decubitus position, the L1-L2 interspace was selected for puncture using a midline approach, and the loss-of-resistance technique confirmed epidural space entry. Puncture depth (skin-to-epidural space) was recorded from needle shaft markings to the nearest 0.1 cm.
L2-L3
On operating room admission, after providing written informed consent for anesthesia, patients underwent standard monitoring (ECG, NIBP, pulse oximetry). Baseline demographic and anthropometric data, including hospital admission ID, sex, height, and weight, were recorded, and body mass index (BMI) was calculated. After positioning in the lateral decubitus position, the L2-L3 interspace was selected for puncture using a midline approach, and the loss-of-resistance technique confirmed epidural space entry. Puncture depth (skin-to-epidural space) was recorded from needle shaft markings to the nearest 0.1 cm.
结局指标
主要结局
epidural depth
时间窗: during epidural anesthesia
epidural depth
Epidural depth
时间窗: Perioperative/Periprocedural
Epidural depth, defined as the vertical distance from the skin surface to the epidural space measured at the time of puncture using the loss-of-resistance technique via the midline approach. Depth was recorded from the needle shaft markings to the nearest 0.1 cm.
次要结局
- Adjusted R²(through study completion, an average of 1 month)
- Root mean square error (RMSE)(through study completion, an average of 1 month)
研究者
Hongbo Zheng
Attending Physician
Tongji Hospital