Comparison of Ultrasound-Guided Caudal Epidural Blocks and Spinal Anesthesia for Anorectal Surgery: A Randomized Controlled Trial

Abstract

Introduction: The aim of this study is to observe the effect of spinal anesthesia (SA) and ultrasound-guided caudal epidural blocks (CEB) on perioperative satisfaction in patients undergoing anorectal surgery.

Methods: A group of 106 patients were randomly allocated to receive either SA (the SA group) or CEB (the CEB group), and 11 patients were excluded. Finally, 95 patients were left, with 48 in the SA group and 47 in the CEB group for data analysis. The primary endpoint was patient satisfaction with the quality of their anesthetic technique. The secondary outcome measures included postoperative pain at 2, 4, 8, 16, 24, and 48 h after surgery at rest, time to first analgesic request, analgesia requirements, incidence of phantom limb syndrome (PLS), time until return of bowel function, time to ambulation, incidence of postoperative nausea and vomiting (PONV), intraoperative mean arterial pressure (MAP) reduction > 20% from baseline, and surgeon satisfaction.

Results: A significantly lower proportion of patients in the SA group was highly satisfied with the quality of their anesthetic technique compared with the CEB group (20.8% versus 68.1%). NRS scores at rest were significantly lower at 4, 8, 16, and 24 h after surgery in the CEB group compared with the SA group. The time to first analgesic request was significantly earlier for patients in the SA group compared with patients in the CEB group. Analgesia requirements, the incidence of PLS, the incidence of PONV, and intraoperative MAP reduction > 20% from baseline were significantly decreased in the CEB group. There were no significant differences between the groups in time until return of bowel function, surgeon satisfaction, or time to ambulation.

Conclusions: Ultrasound-guided caudal epidural blocks have higher patient satisfaction compared with spinal anesthesia.

Trial registration: This study was registered in the Chinese Clinical Trial Registry (ChiCTR 2000041026) on 06/12/2020.

Keywords: Anorectal surgery; Caudal epidural blocks; Phantom limb syndrome; Postoperative pain; Spinal anesthesia.

Fig. 1

Ultrasound image of caudal epidural blocks. 1, cornuae of sacrum; 2, sacrococcygeal ligament; 3, sacral canal; 4, base of sacrum, posterior surface

Fig. 2

Patient flow diagram

Fig. 3

Pain intensity at rest after surgery measured by NRS scores. *P < 0.05 considered statistically significant