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Updated: Feb 22, 2026
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External Cephalic Version: Is it an Effective and Safe Procedure?
Published on: June 6, 2020
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The 90% effective dose of spinal ropivacaine for external cephalic version: A sequential dose-finding study
Qiao Shi1,2, Jing Zheng1,2, Tao Xu1,2
1Department of Anesthesiology, the International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, China.
The Journal of International Medical Research
|February 20, 2026
Summary
The optimal intrathecal ropivacaine dose for external cephalic version (ECV) with spinal anesthesia is 3.0 mg, combined with fentanyl. This dose balances effective pain relief and safety during the procedure.
Area of Science:
- Anesthesiology
- Obstetrics
- Pain Management
Background:
- Spinal anesthesia enhances external cephalic version (ECV) success.
- Optimal ropivacaine dosage for ECV spinal anesthesia is not well-defined.
- Higher ropivacaine doses may pose increased risks.
Purpose of the Study:
- Determine the 90% effective dose (ED90) of intrathecal ropivacaine for ECV.
- Establish optimal analgesic and safety profile for ropivacaine in ECV.
Main Methods:
- Double-blind, prospective, sequential dose-finding study.
- 40 parturients received spinal anesthesia with ropivacaine and fentanyl.
- Dose adjustments based on analgesic efficacy (VAS ≤30 mm) using a biased coin up-and-down design.
Main Results:
- The estimated ED90 of intrathecal ropivacaine with fentanyl was 3.22 mg.
- Median VAS scores were significantly lower in the 3.5 mg group (p < 0.05).
- Maternal and fetal hemodynamics remained stable across dose groups.
Conclusions:
- A 3.0 mg dose of ropivacaine with 10 µg fentanyl offers a good balance of efficacy and safety.
- This dosage is recommended for clinical use in spinal anesthesia for ECV.
- Further research may explore refined dosing strategies for ECV pain management.
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