Nair Nayantara, Gnanasekar Rajiv, Joshi Reesha, Lakshmi R
School of Medicine, Saveetha Medical College and Hospital, Tamil Nadu, India.
Department of Anaesthesia, Saveetha Medical College and Hospital, Tamil Nadu, India.
J Anaesthesiol Clin Pharmacol. 2022 Oct-Dec;38(4):548-552. doi: 10.4103/joacp.JOACP_691_20. Epub 2022 Sep 9.
The main challenge in administration of spinal anesthesia in patients is the unpredictability of the exact skin to subarachnoid space depth (SSD). Approximation of SSD and needle length comes at the expense of patient comfort and multiple attempts increases complications. Our study aimed to evaluate the validity of Stocker's formula to estimate SSD in comparison to ultrasonography and depth of needle insertion. We also aimed to determine an equation to describe the relationship between patient weight and SSD in an Indian population.
This was a prospective observational study. A total of 234 adults of American Society of Anesthesiologists (ASA) category 1 and 2 were selected for the study. The patients underwent spinal anaesthesia and SSD data were determined using weight-based Stocker's formula (DS), ultrasonography (DU), and actual depth of needle insertion (DA). Correlation analysis was performed to determine variables that can predict the SSD. A linear regression was calculated to describe the relationship between patient weight and SSD. SSD data were determined using weight-based Stocker's formula ultrasonography, and actual depth of needle insertion.
Mean SSD using Stocker's formula, ultrasonography, and actual depth of needle insertion was 4.92 ± 0.6 cm, 4.47 ± 0.6 cm, and 4.81 ± 0.6 cm. Our study showed a significant correlation between Stocker's formula and SSD measured by actual depth of needle insertion ( = 0.376). This was described by the derived formula: SSD (cm) =2.522+ [0.031 × weight (kg)].
SSD correlates well with the weight of adult patients. Measurement with Stocker's formula and actual depth showed better correlation than Stocker's formula and ultrasonography. This is valuable in resource-poor areas with a lack of ultrasound machines or expertise in training.
在患者中实施脊髓麻醉的主要挑战在于精确的皮肤至蛛网膜下腔深度（SSD）难以预测。估算SSD和针长会以患者舒适度为代价，而多次尝试会增加并发症。我们的研究旨在评估与超声检查和针插入深度相比，斯托克公式估算SSD的有效性。我们还旨在确定一个方程来描述印度人群中患者体重与SSD之间的关系。
这是一项前瞻性观察性研究。总共选择了234名美国麻醉医师协会（ASA）1级和2级的成年人进行研究。患者接受脊髓麻醉，并使用基于体重的斯托克公式（DS）、超声检查（DU）和针实际插入深度（DA）来确定SSD数据。进行相关性分析以确定可预测SSD的变量。计算线性回归以描述患者体重与SSD之间的关系。使用基于体重的斯托克公式、超声检查和针实际插入深度来确定SSD数据。
使用斯托克公式、超声检查和针实际插入深度测得的平均SSD分别为4.92±0.6厘米、4.47±0.6厘米和4.81±0.6厘米。我们的研究表明，斯托克公式与通过针实际插入深度测得的SSD之间存在显著相关性（ = 0.376）。由推导公式描述为：SSD（厘米）=2.522 + [0.031×体重（千克）]。
SSD与成年患者体重密切相关。与超声检查相比，使用斯托克公式测量与实际深度显示出更好的相关性。这在缺乏超声设备或培训专业知识的资源匮乏地区很有价值。
