Ropivacaine Plasma Concentrations and Pharmacokinetics Following Erector Spinae Plane Block in the Pediatric Population

Phase 4

Completed

Conditions: Anesthesia, Local

Interventions: Drug: Ropivacaine

Registration Number: NCT04298099

Lead Sponsor: Baylor College of Medicine

Brief Summary: The primary aim of this study is to evaluate the pharmacokinetics of serum ropivacaine concentrations following erector spinae plane peripheral nerve blocks in the pediatric population.

Secondary outcomes will assess the efficacy of the block with perioperative morphine equivalent consumption and pain scores.

Detailed Description: This pilot study will enroll patients at Texas Children's Hospital, aged 6 months to \<18 years scheduled to undergo a clinically indicated thoracic surgery with the adjunct of an erector spinae plane block for perioperative pain. A single shot erector spinae plane block is commonly offered for unilateral video-assisted thoracoscopic surgery (VATS) and unilateral chest tube insertions. Following parental consent and child assent to the block, participants will be assigned sequentially to either ropivacaine 0.2% at 0.3ml/kg or ropivacaine 0.5% at 0.3ml/kg. This pilot study poses no additional risk to the patient and the thoracic surgical procedures outlined are those for which an erector spinae plane block would be offered. Furthermore, the block dosing of 0.3ml/kg volumes with ropivacaine 0.2% or 0.5% are not outside of the standard of care or accepted dosages for peripheral nerve blocks.

Venous sample serum ropivacaine levels will be collected prior to ESP block and at 30, 60, 90-minutes and 2, 4, 6 -hours from intravenous access in situ. A baseline alpha-1 acid glycoprotein (AGP) test will be collected and processed by TCH Pathology. Amide local anesthetics are predominantly protein bound to AGP. It is the unbound form that is active. While this study seeks to understand the pharmacokinetics of ropivacaine following a single shot erector spinae plane block, correlate of the AGP will simultaneously ascertain the free vs bound portion.

Samples will be analyzed for the total and free serum ropivacaine concentrations. Pain scores will be collected from nursing records starting from arrival in the Post-Anesthesia Care Unit every 4 hours (up to 12 hours after arrival in PACU). Pain will be measured using The Face, Legs, Activity, Cry, Consolability scale (FLACC), the Wong-Baker FACES Pain Rating Scale (FACES), and the Visual Analogue Scale (VAS).

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 4

Inclusion Criteria

Age: 6 months - < 18 years old;
Chest tubes or minimally invasive video assisted thoracic surgery;
Surgery scheduled between 7AM and 5PM
Weight greater than 4kg

Exclusion Criteria

Renal dysfunction;
Liver dysfunction;
Hypoalbuminemia;
Allergy to local anesthetic;
Spinal hardware or instrumentation;
Scoliosis;
Obesity defined as a BMI >95% percentile

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Ropivacaine 0.2% at 0.3ml/kg	Ropivacaine	Ropivacaine 0.2% at 0.3ml/kg
Ropivacaine 0.5% at 0.3ml/kg	Ropivacaine	Ropivacaine 0.5% at 0.3ml/kg

Primary Outcome Measures

Name	Time	Method
Ropivacaine Concentrations	Prior to administration and at 30, 60, 90-minutes and 2, 4, 6-hours following intravenous access in situ	Pharmacokinetics(PK) of free and total serum ropivacaine concentrations following erector spinae plane peripheral nerve block administration. Blood samples were drawn at the indicated time points for each subject. Laboratory assays will be completed and resulted for all subject samples collected.

Secondary Outcome Measures

Name	Time	Method
Post-anesthesia Care Unit Pain Scores Using VAS	Every 4 hours (up to 12 hours after arrival in PACU)	The visual analog scale (VAS) is a validated, subjective measure for acute and chronic pain. Scores are recorded by making a handwritten mark on a 10-cm line that represents a continuum between "no pain" and "worst pain." A score of 0 represents no pain and 10 represents the worst the pain could be. Scores will be tracked from nursing inputs.
Post-anesthesia Care Unit Pain Scores Using FLACC Scale	Every 4 hours (up to 12 hours after arrival in PACU)	The Face, Legs, Activity, Cry, Consolability Scale (FLACC) is a measurement used to assess pain for children between the ages of 2 months and 7 years or individuals that are unable to communicate their pain. The scale is scored in a range of 0-10 with 0 representing no pain. The scale has five criteria, which are each assigned a score of 0, 1 or 2. Scores will be tracked from nursing inputs. There scale was utilized for one subject. The measure data was collected \<2 hours post-op.
Post-anesthesia Care Unit Pain Scores Using FACES Pain Rating Scale	Every 4 hours (up to 12 hours after arrival in PACU)	The FACES Pain Rating Scale is a tool originally created for children to help them communicate their pain. Now the scale is used around the world with people ages 3 and older. The scale uses 6 faces scored 0-10 with 0 representing no pain. Each facial criteria increases by a score of 2. Scores will be tracked from nursing inputs. There was no data collected for this measure as this scale was not used. Subjects were assessed with a different validated Pain Scale, not data was collected using this scale.
Morphine Equivalents	12 hours	Consumption of morphine per subject was collected post-operatively.