Applicability and effectiveness of ultrasound combined with nerve stimulator-guided lumbosacral plexus block in the supine versus lateral position during surgeries for lower limb fracture-a prospective randomized controlled trial

BACKGROUND: Patients with lower limb fracture often have acute pain and discomfort from changes in position, and such pain affects early postoperative recovery. This study aimed to compare the applicability and effectiveness of ultrasound combined with nerve stimulator-guided lumbosacral plexus block (LSPB) in the supine versus lateral position during lower limb fracture surgery. METHODS: We included 126 patients who underwent elective internal fixation for lower limb fracture who were divided into the S group and the L group by the random number table method and underwent LSPB guided by ultrasound combined with a nerve stimulator in the supine and lateral positions, respectively. The primary outcome was the dose of sufentanil used in surgery. The secondary outcomes were the maximum VAS (visual analogue scale) pain score at position placing for LSPB, the time of position placing, the time for nerve block,the number of puncture attempts,the haemodynamic indicators, the VAS score at 1, 12, and 24 h following surgery, postoperative satisfactory degree to analgesia and adverse events related to nerve block. RESULTS: There was no statistically significant difference in dose of sufentanil used between the two groups(P = 0.142). The maximum VAS pain score at position placing(P < 0.01), the time of position placement(P < 0.01), the time for lumbar plexus block and the time of puncture attempts were significantly lower in the S group than in the L group (P < 0.01). However, the time for sacral plexus block was higher in the S group than in the L group (P = 0.029). There was no significant difference in haemodynamic indicators,number of puncture attempts for the sacral plexus, postoperative VAS scores, postoperative satisfactory degree to analgesia or adverse events related to nerve block between the two groups (all P > 0.05). CONCLUSIONS: Our study provides a more comfortable and better accepted anaesthetic regimen for patients undergoing lower limb fracture surgery. LSPB in the supine position is simple to apply and has definite anaesthetic effects. Additionally, it has a high level of postoperative analgesia and therefore should be widely applied. TRIAL REGISTRATION: The trial was registered prior to patient enrolment at the Chinese Clinical Trail Registry (Date:11/03/2021 Number: ChiCTR2100044117). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12871-022-01710-9.