Conditions: Surgical Anesthesia
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 49
Healthy volunteers: no

Brief summary:
This is a dose finding study to identify the minimum effective anesthetic concentration (MEAC) of ropivacaine to produce insensate body parts sufficient for surgery in supraclavicular and infraclavicular approaches to the brachial plexus, parasacral and popliteal approaches to the sciatic nerve, femoral nerve and transversus abdominis plane (TAP) blocks in adults.

Detailed description:

Arms:
arm 1: Sequential allocation of ropivacaine concentration depending on the success or failure of surgical anesthesia of the previous patient

Interventions: intervention 1: Ropivacaine concentration
Intervention descriptions: intervention 1: Single shot preoperative perineural injection of ropivacaine to achieve surgical anesthesia. The concentration of ropivacaine is lowered by 0.05% after every successful surgical anesthesia specific to that block and raised by 0.05% after every unsuccessful surgical anesthesia specific to that block

Protocol document: