Tianzhen Ji,1,* Lei Xie,1,* Tingyu Zhao,2,* Zhengjie Chen,3 Xiaofen Sun,4 Yan Zhang,1 Cheng Xu2 

1Department of Anesthesiology, Anhui Province Maternal and Child Medical Center, Hefei Maternal and Child Health Hospital, Hefei, Anhui, People’s Republic of China; 2Department of Anesthesiology, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 3Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Zhejiang, People’s Republic of China; 4Department of Anesthesiology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Cheng Xu, Department of Anesthesiology, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China, Email xucheng303@163.com

Background: Combined spinal–epidural (CSE) analgesia delivers rapid labor pain relief, yet high intrathecal opioid doses carry adverse effects, and ultra-low doses shorten block duration. Whether a low intrathecal dose of ropivacaine–sufentanil within CSE reduces clinician-delivered rescue boluses, compared with epidural analgesia (EA) or dural-puncture epidural (DPE), remains unclear.
Methods: Laboring women requesting neuraxial analgesia were randomized to three groups: EA, DPE, and CSE. In the CSE group, analgesia was initiated with 2 mL of solution (1 mL 0.1% ropivacaine plus 1 mL containing 1 μg sufentanil), while the EA and DPE groups received 15 mL of 0.09% ropivacaine with 0.4 μg/mL sufentanil. The primary outcome was the proportion of patients requiring supplemental provider-administered analgesia for breakthrough pain. Secondary outcomes included analgesia onset time, VAS scores at multiple time points, patient-controlled epidural analgesia button presses, and cumulative analgesic consumption.
Results: A total of 131 women completed the study: 42 (EA), 44 (DPE), and 45 (CSE). After adjusting for age, gestational age, cervical dilation, ASA status, BMI, and baseline VAS, the CSE group showed a significantly lower need for supplemental analgesia compared to EA (22% vs 48%; adjusted odds ratio [aOR]: 0.29, 95% CI: 0.10– 0.78; P=0.013). The DPE group (30%) also exhibited a lower incidence than EA, but the difference did not reach significance (aOR: 0.43, 95% CI: 0.16– 1.09; P=0.09). Between CSE and DPE, no significant difference emerged (aOR: 0.66, 95% CI: 0.24– 1.74; P=0.27). The primary hypothesis that CSE would outperform both EA and DPE was not fully supported. For secondary outcomes, the CSE group demonstrated faster onset and significantly lower VAS scores at prespecified intervals than DPE and EA (P< 0.001).
Conclusion: Low-dose intrathecal ropivacaine-sufentanil CSE reduced supplemental analgesia needs versus EA but not DPE. Although CSE produced a faster onset and greater sensory block, its superiority over DPE was not established. Thus, CSE and DPE are clinically acceptable, with CSE potentially favored where minimal breakthrough pain is prioritized; further multicenter studies are warranted to confirm these findings.
Trial Registration Number: ChiCTR2300076206. The trial is publicly available and is registered at www.chictr.org.cn on Sept 7, 2023.
Plain Language Summary: Why did we do this study?
Many women rely on an epidural for pain relief during labor, yet some still feel “breakthrough” pain and need extra medicine from the staff. Doctors can add a minimal dose of anaesthetic and opioid directly into the spinal fluid as part of a combined spinal–epidural (CSE). We wanted to know whether this low-dose CSE gives quicker and more reliable pain relief than the usual epidural (EA) or a related method called dural-puncture epidural (DPE).
What did we do?
We randomly assigned 131 laboring women to one of three groups: (1) EA – the standard epidural; (2) DPE – the needle pierces the outer spinal covering but no drug is injected there; (3) Low-dose CSE – 2 mL of anaesthetic plus opioid is placed inside the spinal fluid before the epidural starts. We recorded how often staff had to give rescue doses, how quickly pain eased, pain scores, drug use, and safety for mother and baby.
What did we find?
Women in the CSE group: (1) Needed staff-given rescue doses about half as often as those with a standard epidural; (2) Felt comfortable more quickly and used less extra medication. Results for DPE lay between the two and were not different from CSE for the primary measure.
What do the results mean?
Both CSE and DPE are safe and effective choices. Low-dose CSE may be preferred when rapid, dependable pain relief is important. Larger studies in several hospitals should confirm these findings.

Keywords: combined spinal-epidural, dural puncture epidural, epidural analgesia, labor analgesia