Abstract:

Objective To investigate the clinical efficacy of the median and paramedian approaches in ultrasound-guided combined spinal-epidural anesthesia for patients with hemorrhoidectomy and to evaluate the differences between the two techniques. Methods A retrospective analysis was performed on 90 AIDS patients who underwent hemorrhoidectomy under combined spinal-epidural anesthesia from February 2024 to March 2025. The patients were categorized into two groups based on the ultrasound-guided puncture approach： a midline approach group and a paramedian approach group. In the midline approach group， anatomical landmarks such as the spinous process space， facet joint， and transverse process were identified in the transverse axial plane for accurate localization. The puncture site was determined as the midpoint of the interspinous space along the spinal midline， and an out-of-plane puncture technique was utilized. In the paramedian approach group， positioning was performed by scanning the lamina in the sagittal oblique plane. The dorsal complex structure space with the clearest visibility was centered under the probe， and an in-plane puncture technique was applied， with the needle advanced from the caudal to the cephalad direction to complete the combined spinal-epidural procedure. Data regarding puncture performance， complications， and anesthetic efficacy were systematically recorded and assessed for both groups. Results Intergroup analysis demonstrated that the paramedian approach group exhibited significantly fewer total puncture attempts and a higher success rate on the first attempt （P < 0.05）. No significant differences were observed between the two groups regarding the need to change puncture levels or modify the puncture approach （P > 0.05）. The midline approach group showed a significantly higher incidence of paresthesia and a greater frequency of postoperative puncture site tenderness at two days post-surgery compared to the paramedian approach group （P < 0.05）. Anesthetic efficacy was comparable between the two groups， with no statistically significant difference detected （P > 0.05）. Conclusions In hemorrhoidectomy procedures for AIDS patients， the paramedian approach demonstrates advantages over the median approach in terms of puncture success and reduced complications associated with ultrasound-guided combined spinal-epidural anesthesia. However， no significant difference in anesthetic efficacy is observed between the two approaches.

Key words: ultrasound guidance, combined spinal-epidural anesthesia, midline approach, paramedian approach, acquired immune deficiency syndrome