PharmacokineticsNCT02755532

Bupivacaine Pharmacokinetics in Ultrasound-guided Axillary Brachial Plexus Block.

A study testing Bupivacaine 0,25% and Bupivacaine 0,5% in people with Pharmacokinetics and Anesthetics, Local, run by Federal University of São Paulo.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

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Trial summary

Who is it for?: Ages 18 to 65 years
Conditions the study is for: Pharmacokinetics, Anesthetics, Local
What is being tested?: Bupivacaine 0,25% and Bupivacaine 0,5%
Type of treatment: Injection or infusion
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 30 participants
Where: No sites listed yet
Study dates: Jan 2014to Oct 2015
Phase: Interventional
Are there results?: None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 to 65 years
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

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.

Who cannot join

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

About this study

Official title: A Clinical and Pharmacokinetic Study to Evaluate the Influence of Two Bupivacaine Concentrations on Peak Plasma After Ultrasound-guided Axillary Brachial Plexus Block

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.

Conditions: Pharmacokinetics, Anesthetics, Local
Being tested: Bupivacaine 0,25%, Bupivacaine 0,5%
Keywords: Pharmacokinetics, Bupivacaine, Axillary brachial plexus block

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

Bupivacaine 0,25%Drug
Venous blood samples were collected prior to blocking , every 15 min during the first hour after completion of the blocking and every 30 min during the second hour after completion using an exclusive cannula. Then, 5 ml was drawn off and was stored in two EDTA tubes (BD, Franklin Lakes, NJ, USA). The EDTA tubes were centrifuged at 3,500xg for 10 min to obtain the blood plasma. This plasma was then stored in cryogenic tubes in a freezer at -80 °C until the time of the analysis. A high-performance liquid chromatography apparatus (Shimadzu, Kyoto, Japan) coupled to a Bruker mass spectrometer (MS), model Amazon (USA), with electrospray source ionization and a sequential mass spectrometry system (MS/MS) were used for the analysis. After obtaining the precursor ion, a fragment was obtained via a collision-induced dissociation process. The following molecular ions were selected: 289.0 m/z==>140.1 m/z. The methodology was validated according to the international FDA recommendations.
Bupivacaine 0,5%Drug
Venous blood samples were collected prior to blocking , every 15 min during the first hour after completion of the blocking and every 30 min during the second hour after completion using an exclusive cannula. Then, 5 ml was drawn off and was stored in two EDTA tubes (BD, Franklin Lakes, NJ, USA). The EDTA tubes were centrifuged at 3,500xg for 10 min to obtain the blood plasma. This plasma was then stored in cryogenic tubes in a freezer at -80 °C until the time of the analysis. A high-performance liquid chromatography apparatus (Shimadzu, Kyoto, Japan) coupled to a Bruker mass spectrometer (MS), model Amazon (USA), with electrospray source ionization and a sequential mass spectrometry system (MS/MS) were used for the analysis. After obtaining the precursor ion, a fragment was obtained via a collision-induced dissociation process. The following molecular ions were selected: 289.0 m/z==>140.1 m/z. The methodology was validated according to the international FDA recommendations.

Study groups in NCT02755532
Study group	Role	What they receive
Bupivacaine 0,25%	Active comparator	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. Receives: Drug: Bupivacaine 0,25%
Bupivacaine 0,5%	Active comparator	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. Receives: Drug: Bupivacaine 0,5%

What is being measured

The primary outcome is the main question the study is designed to answer.

Peak Venous Plasma level of bupivacaine.
The aim of this study was to evaluate the difference in peak plasma levels obtained after ultrasound guided axillary brachial plexus block using two different bupivacaine concentrations to maintain the infused mass. Venous blood samples were collected prior to blocking , every 15 min during the first hour after completion of the blocking and every 30 min during the second hour after completion using an exclusive cannula. Then, 5 ml was drawn off and was stored in two EDTA tubes (BD, Franklin Lakes, NJ, USA). The EDTA tubes were centrifuged at 3,500xg for 10 min to obtain the blood plasma. This plasma was then stored in cryogenic tubes in a freezer at -80 °C until the time of the analysis. A high-performance liquid chromatography apparatus (Shimadzu, Kyoto, Japan) coupled to a Bruker mass spectrometer (MS), model Amazon (USA), with electrospray source ionization and a sequential mass spectrometry system (MS/MS) were used for the analysis.
Measured: 2 hours

Secondary outcomes (1)

Latency - The latency period was defined as the time interval between time zero and the time when surgical anesthesia was obtained.
This evaluation occurred every 5 min until the 30th min after blocking. During this period, if surgical anesthesia was not obtained, then a complementary bupivacaine injection was administered distal to the axilla and the patient was excluded from the protocol. Surgical anesthesia was defined as a motor scale of 2 or lower; an absence of cold and pinprick sensation.
Measured: 30 minutes

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

Jan 2014Oct 2015

First posted29 Apr 2016 (estimated)
Study startJan 2014
Primary completionJul 2015
Study completionOct 2015

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Publications (9)Papers the sponsor has linked to this study.
Other trials for PharmacokineticsStudies of the same condition, open and under way.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase N/A
Primary purpose: Basic science
Allocation: Randomised
Intervention model: Parallel groups
Masking: Double blind
Who is masked: Participant, Investigator
Enrolment: 30 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT02755532
Sponsor's protocol ID: Bupvacaine Pharmacokinetic
Status last verified: Apr 2016
First submitted: 22 Apr 2016
Last updated: 29 Apr 2016
Results posted: No
Data monitoring committee: Yes
Individual data sharing: No

Publications

Mulroy MF. Systemic toxicity and cardiotoxicity from local anesthetics: incidence and preventive measures. Reg Anesth Pain Med. 2002 Nov-Dec;27(6):556-61. doi: 10.1053/rapm.2002.37127. No abstract available.
PubMed 12430104
Rosenberg PH, Veering BT, Urmey WF. Maximum recommended doses of local anesthetics: a multifactorial concept. Reg Anesth Pain Med. 2004 Nov-Dec;29(6):564-75; discussion 524. doi: 10.1016/j.rapm.2004.08.003.
PubMed 15635516
Liu SS, Ortolan S, Sandoval MV, Curren J, Fields KG, Memtsoudis SG, YaDeau JT. Cardiac Arrest and Seizures Caused by Local Anesthetic Systemic Toxicity After Peripheral Nerve Blocks: Should We Still Fear the Reaper? Reg Anesth Pain Med. 2016 Jan-Feb;41(1):5-21. doi: 10.1097/AAP.0000000000000329. No abstract available.
PubMed 26650424
Vasques F, Behr AU, Weinberg G, Ori C, Di Gregorio G. A Review of Local Anesthetic Systemic Toxicity Cases Since Publication of the American Society of Regional Anesthesia Recommendations: To Whom It May Concern. Reg Anesth Pain Med. 2015 Nov-Dec;40(6):698-705. doi: 10.1097/AAP.0000000000000320.
PubMed 26469367
Dillane D, Finucane BT. Local anesthetic systemic toxicity. Can J Anaesth. 2010 Apr;57(4):368-80. doi: 10.1007/s12630-010-9275-7. Epub 2010 Feb 12.
PubMed 20151342
Lee LA, Posner KL, Cheney FW, Caplan RA, Domino KB. Complications associated with eye blocks and peripheral nerve blocks: an american society of anesthesiologists closed claims analysis. Reg Anesth Pain Med. 2008 Sep-Oct;33(5):416-22. doi: 10.1016/j.rapm.2008.01.016.
PubMed 18774510
Auroy Y, Narchi P, Messiah A, Litt L, Rouvier B, Samii K. Serious complications related to regional anesthesia: results of a prospective survey in France. Anesthesiology. 1997 Sep;87(3):479-86. doi: 10.1097/00000542-199709000-00005.
PubMed 9316950
Takeda A, Ferraro LH, Rezende AH, Sadatsune EJ, Falcao LF, Tardelli MA. Minimum effective concentration of bupivacaine for axillary brachial plexus block guided by ultrasound. Braz J Anesthesiol. 2015 May-Jun;65(3):163-9. doi: 10.1016/j.bjane.2013.11.007. Epub 2015 Feb 16.
PubMed 25925026
Cohen LS, Rosenthal JE, Horner DW Jr, Atkins JM, Matthews OA, Sarnoff SJ. Plasma levels of lidocaine after intramuscular administration. Am J Cardiol. 1972 Apr;29(4):520-3. doi: 10.1016/0002-9149(72)90442-0. No abstract available.
PubMed 5016830

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

Official record

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Study at a glance

From the registry record, last updated by the sponsor on 29 Apr 2016. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: A Clinical and Pharmacokinetic Study to Evaluate the Influence of Two Bupivacaine Concentrations on Peak Plasma After Ultrasound-guided Axillary Brachial Plexus Block
ClinicalTrials.gov ID: NCT02755532
Acronym / sponsor ID: Bupvacaine Pharmacokinetic
Conditions: Pharmacokinetics, Anesthetics, Local
Keywords: Pharmacokinetics, Bupivacaine, Axillary brachial plexus block
Study type: Interventional
Recruitment status: Completed
Enrolment: 30 participants (actual)
Lead sponsor: Federal University of São PauloUniversity, hospital or other
Collaborators: Fundação de Amparo à Pesquisa do Estado de São Paulo
Study start: Jan 2014
Primary completion: Jul 2015 (actual)
Study completion: Oct 2015 (actual)
First posted: 29 Apr 2016 (estimated)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Study design

Primary purpose: Basic science
Allocation: Randomised
Intervention model: Parallel groups
Masking: Double blind (participant, investigator)
Number of arms: 2

Arm	Type	Receives
Bupivacaine 0,25%	Active comparator	Drug: Bupivacaine 0,25%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.
Bupivacaine 0,5%	Active comparator	Drug: Bupivacaine 0,5%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.

Who may qualify

Ages: 18 to 65 years
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (4 listed)

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.

Key exclusion criteria (4 listed)

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

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
Bupivacaine 0,25%Venous blood samples were collected prior to blocking , every 15 min during the first hour after completion of the blocking and every 30 min during the second hour after completion using an exclusive cannula. Then, 5 ml was drawn off and was stored in two EDTA tubes (BD, Franklin Lakes, NJ, USA). The EDTA tubes were centrifuged at 3,500xg for 10 min to obtain the blood plasma. This plasma was then stored in cryogenic tubes in a freezer at -80 °C until the time of the analysis. A high-performance liquid chromatography apparatus (Shimadzu, Kyoto, Japan) coupled to a Bruker mass spectrometer (MS), model Amazon (USA), with electrospray source ionization and a sequential mass spectrometry system (MS/MS) were used for the analysis. After obtaining the precursor ion, a fragment was obtained via a collision-induced dissociation process. The following molecular ions were selected: 289.0 m/z==>140.1 m/z. The methodology was validated according to the international FDA recommendations.	Drug	Bupivacaine 0,25%
Bupivacaine 0,5%Venous blood samples were collected prior to blocking , every 15 min during the first hour after completion of the blocking and every 30 min during the second hour after completion using an exclusive cannula. Then, 5 ml was drawn off and was stored in two EDTA tubes (BD, Franklin Lakes, NJ, USA). The EDTA tubes were centrifuged at 3,500xg for 10 min to obtain the blood plasma. This plasma was then stored in cryogenic tubes in a freezer at -80 °C until the time of the analysis. A high-performance liquid chromatography apparatus (Shimadzu, Kyoto, Japan) coupled to a Bruker mass spectrometer (MS), model Amazon (USA), with electrospray source ionization and a sequential mass spectrometry system (MS/MS) were used for the analysis. After obtaining the precursor ion, a fragment was obtained via a collision-induced dissociation process. The following molecular ions were selected: 289.0 m/z==>140.1 m/z. The methodology was validated according to the international FDA recommendations.	Drug	Bupivacaine 0,5%

Primary outcome

Peak Venous Plasma level of bupivacaine.
Time frame: 2 hours
The aim of this study was to evaluate the difference in peak plasma levels obtained after ultrasound guided axillary brachial plexus block using two different bupivacaine concentrations to maintain the infused mass. Venous blood samples were collected prior to blocking , every 15 min during the first hour after completion of the blocking and every 30 min during the second hour after completion using an exclusive cannula. Then, 5 ml was drawn off and was stored in two EDTA tubes (BD, Franklin Lakes, NJ, USA). The EDTA tubes were centrifuged at 3,500xg for 10 min to obtain the blood plasma. This plasma was then stored in cryogenic tubes in a freezer at -80 °C until the time of the analysis. A high-performance liquid chromatography apparatus (Shimadzu, Kyoto, Japan) coupled to a Bruker mass spectrometer (MS), model Amazon (USA), with electrospray source ionization and a sequential mass spectrometry system (MS/MS) were used for the analysis.

1 secondary outcome

Latency - The latency period was defined as the time interval between time zero and the time when surgical anesthesia was obtained.
Time frame: 30 minutes

Results and safety

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 29 Apr 2016.
Background: PubMed 12430104Mulroy MF. Systemic toxicity and cardiotoxicity from local anesthetics: incidence and preventive measures. Reg Anesth Pain Med. 2002 Nov-Dec;27(6):556-61. doi: 10.1053/rapm.2002.37127. No abstract available.
Background: PubMed 15635516Rosenberg PH, Veering BT, Urmey WF. Maximum recommended doses of local anesthetics: a multifactorial concept. Reg Anesth Pain Med. 2004 Nov-Dec;29(6):564-75; discussion 524. doi: 10.1016/j.rapm.2004.08.003.
Results publication: PubMed 26650424Liu SS, Ortolan S, Sandoval MV, Curren J, Fields KG, Memtsoudis SG, YaDeau JT. Cardiac Arrest and Seizures Caused by Local Anesthetic Systemic Toxicity After Peripheral Nerve Blocks: Should We Still Fear the Reaper? Reg Anesth Pain Med. 2016 Jan-Feb;41(1):5-21. doi: 10.1097/AAP.0000000000000329. No abstract available.
Results publication: PubMed 26469367Vasques F, Behr AU, Weinberg G, Ori C, Di Gregorio G. A Review of Local Anesthetic Systemic Toxicity Cases Since Publication of the American Society of Regional Anesthesia Recommendations: To Whom It May Concern. Reg Anesth Pain Med. 2015 Nov-Dec;40(6):698-705. doi: 10.1097/AAP.0000000000000320.
Results publication: PubMed 20151342Dillane D, Finucane BT. Local anesthetic systemic toxicity. Can J Anaesth. 2010 Apr;57(4):368-80. doi: 10.1007/s12630-010-9275-7. Epub 2010 Feb 12.
Results publication: PubMed 18774510Lee LA, Posner KL, Cheney FW, Caplan RA, Domino KB. Complications associated with eye blocks and peripheral nerve blocks: an american society of anesthesiologists closed claims analysis. Reg Anesth Pain Med. 2008 Sep-Oct;33(5):416-22. doi: 10.1016/j.rapm.2008.01.016.
Results publication: PubMed 9316950Auroy Y, Narchi P, Messiah A, Litt L, Rouvier B, Samii K. Serious complications related to regional anesthesia: results of a prospective survey in France. Anesthesiology. 1997 Sep;87(3):479-86. doi: 10.1097/00000542-199709000-00005.
Results publication: PubMed 25925026Takeda A, Ferraro LH, Rezende AH, Sadatsune EJ, Falcao LF, Tardelli MA. Minimum effective concentration of bupivacaine for axillary brachial plexus block guided by ultrasound. Braz J Anesthesiol. 2015 May-Jun;65(3):163-9. doi: 10.1016/j.bjane.2013.11.007. Epub 2015 Feb 16.
Results publication: PubMed 5016830Cohen LS, Rosenthal JE, Horner DW Jr, Atkins JM, Matthews OA, Sarnoff SJ. Plasma levels of lidocaine after intramuscular administration. Am J Cardiol. 1972 Apr;29(4):520-3. doi: 10.1016/0002-9149(72)90442-0. No abstract available.
Individual participant dataSharing planned: No

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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Leonardo HC Ferraro, PhD principal investigator

Federal University of São Paulo

Questions about this trial

What is this clinical trial studying?

A study testing Bupivacaine 0,25% and Bupivacaine 0,5% in people with Pharmacokinetics and Anesthetics, Local, run by Federal University of São Paulo.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 4 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 29 Apr 2016. Status can change between updates, so confirm with the study contact before making plans.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Peak Venous Plasma level of bupivacaine. (time frame: 2 hours). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT02755532, which also lists 9 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Apr 2016.