Peak Plasma Levels of Bupivacaine After an Erector Spinae Block (ESP)

NCT ID: NCT03841409

Last Updated: 2022-05-31

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 18 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2019-06-14
• Study Completion Date: 2019-10-16

Brief Summary

The primary objective of the study is to measure plasma levels of bupivacaine following erector spinae (ESP) regional block in patients undergoing mastectomy.

Detailed Description

Breast cancer is one of the most frequent types of cancer in women. Mastectomy is important in treating these cases; however, sometimes it is associated with acute and chronic pain. Multimodal analgesia, combining drug therapy and regional anesthesia, can help in preventing acute and perhaps chronic pain in breast cancer patients undergoing mastectomy.

Erector spinae block is a new regional anesthesia technique that has emerged to treat thoracic pain following thoracic and breast surgery. It consists of injecting local anesthetics in the space located between the erector and paravertebral muscles using ultrasound guidance. The injection can be done at the level of T5 allowing distribution of the drug to upper and lower dermatomes.

The dose of local anesthetic injected after erector spinae block should aim to maximize analgesia while minimizing the chance of toxic systemic concentrations. Defining the rate of absorption of local anesthetics into the blood after an erector spinae block will therefore help anesthesiologists determinate optimal analgesic doses, in terms of both safety and effectiveness.

This observational study will determine bupivacaine pharmacokinetics after single shot erector spinae block with bupivacaine, to further define the right dose and duration of surveillance in post-anesthesia care.

Methods:

For the erector spinae block, the patient will be placed in the sitting position. Using an ultrasound machine with a high frequency linear probe (Sonosite, HFL50 15-6MHz) placed in the parasagittal plane, 3cm away from the midline, the anesthesiologist will position an insulated hyperechoic needle (50-80 mm, 22 gauge, SonoPlex STIM, Nanoline, Pajun, Germany) at the level of the 5th thoracic vertebrae, between the erector spinae and the paravertebral muscles. The anesthesiologist will confirm the correct position of the needle with the injection of 1 mL of 5% dextrose. Then, after negative aspiration, he will inject bupivacaine 0.5% with epinephrine 5 mcg/mL in 5 ml aliquots for a total dose of 2mg/kg of ideal body weight (maximum of 150mg).

The end of injection will be considered as T0. Collection of 4.5mL of blood will be performed at T10min, T20min, T30min, T45min, T60min, T90min, T120min, T180min, and T240min.

Blood tubes will be immediately placed on ice to be ultimately sent to the laboratory for centrifugation and measurement of bupivacaine level using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for each of the samples.

General anesthesia will then be induced in the operating room with no additional bupivacaine allowed by the anesthesiologist or the surgeon. After surgery, in the Post-Anesthesia Care Unit, the level of the sensory block will be identified by pinprick and the quality of analgesia will be evaluated using a verbal numerical rating scale, and opioid consumption will be noted.

Conditions

Pharmacokinetics; Anesthesia, Local

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Bupivacaine dosage in ESP block

The pharmacokinetics of bupivacaine 0.5% with epinephrine 5 mcg/mL for a total dose of 2mg/kg of ideal body weight following an ESP block will be determined by the collection of blood samples at predetermined time points.

Collection of blood samples

Intervention Type: OTHER

Nine blood samples will be collected to determine bupivacaine pharmacokinetics at T10min, T20min, T30min, T45min, T60min, T90min, T120min, T180min, and T240min. T0 will be defined as the end of bupivacaine injection.

Interventions

Collection of blood samples

Nine blood samples will be collected to determine bupivacaine pharmacokinetics at T10min, T20min, T30min, T45min, T60min, T90min, T120min, T180min, and T240min. T0 will be defined as the end of bupivacaine injection.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• ASA I-III
• Undergoing unilateral mastectomy under erector spinae block and general anesthesia

Exclusion Criteria

• Patient's refusal or inability to consent
• Allergy, hypersensibility or resistance to local anesthetic
• Contra-indication to regional anesthesia: infection in the designated area, acquired or congenital coagulopathy
• Severe hepatic or renal insufficiency (GFR<30 mL/min)

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 90 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Centre hospitalier de l'Université de Montréal (CHUM)

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Stephan Williams, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Centre hospitalier de l'Université de Montréal (CHUM)

Locations

Centre Hospitalier de l'Université de Montréal (CHUM)

Montreal, Quebec, Canada

Countries

Canada

Other Identifiers

18.308

Identifier Type: -

Identifier Source: org_study_id