Impact of Real-Time Ultrasound-Guided Spinal Anesthesia Versus Landmark-Guided Spinal Anesthesia on Anesthesia Procedural Time

Intraspinal anesthesia, traceable to the late 19th century, involves injecting local anesthetics into the spinal canal to block nerve signals, relieving pain and relaxing muscles for surgery. Compared with general anesthesia, it has advantages: smaller impact on the central nervous system, lower drug dosage (reducing systemic poisoning risk), precise block plane control (protecting respiratory/cardiac function), and benefits for mothers and fetuses. However, traditional blind puncture faces challenges in special patients (obese, post-spinal surgery, or pathological cases). It relies on "loss of sensory resistance," prone to misjudgment, leading to dura rupture or spinal cord injury. Obese pregnant women have hard-to-palpate spinous processes; the elderly have ligament calcification/narrowed intervertebral spaces, affecting positioning and ultrasound imaging. Ultrasound guidance has advanced since 1984 (first used to measure epidural space depth, reducing complications). It aids obese pregnant women in locating spinal structures, guides pediatric epidural catheter placement, and improves first-attempt success with better resolution. Adjusting the ultrasound probe to a sagittal midline inner oblique angle solves imaging issues in elderly patients. Clinically, 24G/25G fine needles for ultrasound-guided lumbar puncture may deform; the "needle-in-a-needle" technique (using a larger guide needle) reduces tissue damage and accidental dura puncture, while minimizing skin punctures. Small-sample studies confirm ultrasound's value in vertebral localization and real-time guidance, but the efficacy of ultrasound vs. surface marking remains controversial due to lack of large-sample data. This article provides evidence-based reference via retrospective analysis of 3,597 cases.