Bupivacaine Pharmacokinetics in Ultrasound-guided Axillary Brachial Plexus Block.

Federal University of São Paulo

Status: Completed

Conditions: Anesthetics, Local; Pharmacokinetics

Treatments: Drug: Bupivacaine 0,5%; Drug: Bupivacaine 0,25%

Study type: Interventional

Funder types: Other

Identifiers

NCT02755532

Bupvacaine Pharmacokinetic

Details and patient eligibility

About

Introduction: The risk of systemic toxicity when using bupivacaine is a persistent problem, making its pharmacokinetic study crucial to the safety of regional anesthesia (RA). Little evidence exists regarding the effect of different concentrations of this drug on peak plasma levels. The present study compares two bupivacaine concentrations to establish how the concentration and exchange area affect the peak plasma level of this drug during axillary brachial plexus block. Latency and postoperative analgesia periods were also compared.

Methods: 32 patients were randomly assigned to two groups. In the 0.25% group, 10 ml of 0.25% bupivacaine was injected per nerve; in the 0.5% group, 5 ml of 0.5% bupivacaine was injected per nerve. Peripheral blood samples were collected every 15 min during the first hour and every 30 min during the second hour to establish serum level dosage. High-performance liquid chromatography coupled with mass spectrometry was used for the analysis.

Enrollment: 30 patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• candidates for elective surgery of the distal forearm and hand for whom brachial plexus anesthesia and analgesia were indicated.
• physical status of I or II according to American Society of Anesthesiologists (ASA) criteria
• body mass index (BMI) of less than 35 kg/m2
• Signed the free and informed consent document.

Exclusion criteria

• cognitive impairment
• infection at the block puncture site
• coagulopathy
• history of bupivacaine allergy

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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30 participants in 2 patient groups

Bupivacaine 0,25%

Active Comparator group

Description:

Routine surgical procedure monitoring with an electrocardiogram, sphygmomanometer, and pulse oximeter was performed. One experienced anesthesiologist performed an ultrasound guided axillary brachial plexus block (S Series, FUJIFILM Sonosite, Seattle, USA) with the patient in the supine position. Local anesthetic injection was performed on each nerve identified in this pathway (i.e., the radial nerve, the ulnar nerve, the median nerve, and the musculocutaneous nerve) In the group bupicavaine 0.25%, 10 ml of 0.25% bupivacaine was injected into each nerve, for a total of 40 ml per patient.

Treatment:

Drug: Bupivacaine 0,25%

Bupivacaine 0,5%

Active Comparator group

Description:

Routine surgical procedure monitoring with an electrocardiogram, sphygmomanometer, and pulse oximeter was performed. One experienced anesthesiologist performed an ultrasound guided axillary brachial plexus block (S Series, FUJIFILM Sonosite, Seattle, USA) with the patient in the supine position. Local anesthetic injection was performed on each nerve identified in this pathway (i.e., the radial nerve, the ulnar nerve, the median nerve, and the musculocutaneous nerve). In the group bupivacaine 0.5% , 5 ml of 0.5% bupivacaine was injected into each nerve, for a total of 20 ml per patient.

Treatment:

Drug: Bupivacaine 0,5%