Clinical trial NCT03059498: PECS Block: Plasma Bupivacaine Level
Official title: Determining Plasma Bupivacaine Levels Following Pectoral Nerve Blocks: A Prospective Observational Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: EARLY_PHASE1
Conditions: Nerve Blocks
Keywords: PECS I and II
PECS blocks
Lead sponsor: Wake Forest University Health Sciences
Sponsor class: OTHER
First posted: 2017-02-23
Enrollment: 20
Sex: ALL
Minimum age (years): 18
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: OTHER

Brief summary: The purpose of this study is to determine peak plasma bupivacaine concentrations in a similar fashion for PECS I/II blocks. The investigators hypothesis is that the mean peak plasma levels for patients undergoing PECS I/II blocks will be less than the levels reported to cause early neurotoxicity of \[2.2 (0.9) micrograms/ml\]6 in patients receiving intravenous bupivacaine infusions.

Detailed description: Regional anesthesia techniques are common modalities used to provide analgesia following both upper and lower extremity surgeries. It is also often used for truncal procedures for the same purpose. A relatively new truncal block, first described in 2012 by Blanco, called the pectoralis nerve block (PECS I and II block) has been used successfully for breast surgery1-3. Despite its description and success in clinical practice, the extent of systemic absorption from this truncal plane block has not been described to date. However, in a study published in the British Journal of Anesthesia, this has been done for another truncal plane block, the transverse abdominus plane (TAP) block where the local anesthetic was noted to peak and had a mean total concentration of ropivacaine occurring at 30 minutes after the block4. During this study, samples were taken at 10, 20, 30, 45, 60, 90, 120, 180, and 240 minutes. The investigators anticipate that since this is a similar truncal plane block, absorption will be comparable in terms of timing. However, the concentration of drug absorbed may be different given the proximity to the ribs, intercostal and thoracic vasculature, and a higher concentration of local given the smaller plane for local anesthetic spread. Given that the investigators want to find the peak of the curve and the peak concentration of bupivacaine from the PECS block, the investigators feel will need 5 samples at the times outlined below. This number of samples was chosen to approximate a study published in 2004 where ten subjects received ropivacaine for scalp blocks and serum ropivacaine levels were measured at 15, 30, 45, 60, 90, and 120 minutes5. The investigators feel that the 120 minute measurement is well beyond the peak plasma level of bupivacaine given the findings in the TAP and scalp studies. Therefore,the investigators will collect the following samples at these times after the block is completed: 5, 10, 20, 40, 60, and 90 minutes. The purpose of this study is to determine peak plasma bupivacaine concentrations in a similar fashion for PECS I/II blocks. The investigators hypothesis is that the mean peak plasma levels for our patients undergoing PECS I/II blocks will be less than the levels reported to cause early neurotoxicity of \[2.2 (0.9) micrograms/ml\]6 in patients receiving intravenous bupivacaine infusions.

Eligibility criteria: Inclusion Criteria:

* Patients receiving a unilateral PECS I and II block for any surgery being provided by Wake Forest Baptist Medical Center

Exclusion Criteria:

* Subjects with contraindications to regional anesthesia, such as a history of allergy to amide local anesthetics,
* presence of a progressive neurological deficit,
* a pre-existing coagulopathy,
* infection at site of injection.
* or the following conditions:
* patient receiving any other additional local anesthetic from another procedure
* infection over site of block
* patient refusal
* significant renal or liver dysfunction on laboratory analysis
* weight \<60 kg
* pregnancy

Primary outcomes:
measure: Peak plasma bupivacaine concentration
timeFrame: 90 minutes after dose
measure: Bupivacaine mean concentration
timeFrame: 90 Minutes after dose
measure: Standard deviations of plasma bupivacaine concentrations
timeFrame: 90 minutes after dose
Secondary outcomes:
measure: Rates of block success
timeFrame: 30 minutes after block
measure: Rates of adequate ultrasound success of appropriate separation of the muscular layers for each block.
timeFrame: At the end of the block placement, 0 minutes timepoint.
measure: Rates of symptoms of local anesthetic systemic toxicity
timeFrame: 90 minutes after block
Other outcomes:
Locations:
city: Winston-Salem
country: United States
facility: Wake Forest Baptist Medical Center
state: North Carolina
Study officials:
affiliation: Wake Forest University Health Sciences
name: J. Douglas Jaffe, DO
role: PRINCIPAL_INVESTIGATOR
References: