Minimum Effective Dose of 0.5% Bupivacaine for Ultrasound-guided Spinal Anesthesia Using Taylor's Approach

Not Applicable

Completed

• Conditions: Lower Limb Surgery
• Interventions: Procedure: spinal anesthesia

• Registration Number: NCT03899038
• Lead Sponsor: Huazhong University of Science and Technology

Brief Summary

This study aims to determine the minimum effective dose of bupivacaine 0.5% in 90% of patients undergoing lower limb surgery with ultrasound-guided spinal anesthesia using Taylor's approach. A biased coin design up-and-down sequential method is applied. The initial dose is 15 mg of bupivacaine 0.5%. After 45 successful spinal anesthesia, the ED90 of bupivacaine 0.5% will be calculated.

Detailed Description

The minimum effective dose of local anesthetics for spinal anesthesia using Taylor's approach is not known. This study aims to determine the minimum effective dose of bupivacaine 0.5% using a biased coin design up-and-down sequential method. Patients will receive real-time ultrasound guided spinal anesthesia using Taylor's approach. The initial dose is chosen as 15 mg on the basis of clinical experience. Subsequently, if a patient has an inadequate block, the bupivacaine dose is increased by 2 mg in the next subject. If a patient has a successful block, the next subject is randomized to receive either a lower dose (with a decrement of 2 mg), with a probability of b = 0.11, or the same dose, with a probability of 1 - b = 0.89. Forty five successful blocks will be accomplished. MED90 will be calculated by isotonic regression.

Study Timeline

• Study First Submitted: 2019-03-27
• Study First Submitted QC: 2019-03-29
• Study First Posted: 2019-04-02
• Study Start: 2019-04-08
• Primary Completion: 2019-07-09
• Study Completion: 2019-07-31
• Status Verified: 2019-09
• Last Update Submitted: 2019-09-14
• Last Update Posted: 2019-09-18

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 56

Inclusion Criteria

• American Society of Anesthesiologists physical statusⅠ- Ⅲ
• Lower limb surgery, expected operation time within 2 hours

Exclusion Criteria

• Patient refusal
• American Society of Anesthesiologists physical status IV/V
• Peripheral neuropathy
• skin infection at the site of injection
• allergy to bupivacaine or lidocaine
• BMI > 35 kg/m2
• coagulation disorders

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Deceasing	spinal anesthesia	Spinal anesthesia with decreasing dose. Real-time ultrasound-guided spinal anesthesia Using Taylor's approach.
Similar	spinal anesthesia	Spinal anesthesia with similar dose. Real-time ultrasound-guided spinal anesthesia Using Taylor's approach.

Primary Outcome Measures

Name	Time	Method
The minimum effective dose of bupivacaine in spinal anesthesia using Taylor's approach	up to 6 months	The minimum effective dose of bupivacaine in spinal anesthesia using Taylor's approach is based on 45 successful spinal anesthesia performed in patients undergoing lower limb surgery.

Secondary Outcome Measures

Name	Time	Method
postoperative neurological complications	up to 3 months postoperation	postoperative neurological complications
the duration of sensory spinal anaesthesia for the lower extremity	up to 3 days postoperation	the duration of sensory spinal anaesthesia for the lower extremity
the upper level of the sensory block 25 min after bupivacaine injection	25 min	the upper level of the sensory block 25 min after bupivacaine injection
the incidence of hypotension	during anethesia and operation	the incidence of hypotension

Trial Locations

Locations (1)

Department of Anaesthesiology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology; 🇨🇳 Wuhan, Hubei, China