Age-Based and Weight-Based Bupivacaine Dosing for Pediatric Spinal Anesthesia for Elective Infra-Umbilical Surgeries

A Comparative Study Between Age-Based and Weight-Based Bupivacaine Dosing for Pediatric Spinal Anesthesia in Children Undergoing Elective Infra-Umbilical Surgeries: A Randomized Double-Blinded Controlled Trial

Pediatric anesthesia presents distinctive challenges, particularly concerning appropriate dosage administration of local anesthetics for spinal anesthesia (SA). Spinal anesthesia in infants has been linked to a lower incidence of hypotension, hypoxia, bradycardia, and postoperative apnea in comparison to general anesthesia (GA); ensuring a high level of cardiovascular and respiratory stability.

Additionally, SA has been linked to lower operating room time, post-anesthesia care unit, hospital length of stay, corticosteroid administration, narcotic requirements, postoperative emesis, and cardiopulmonary complications in comparison to GA.

A reduction in systemic blood pressure frequently accompanies neuraxial blocks in adults, necessitating intervention. Nevertheless, spinal, caudal, or epidural blocks administered to children under six years old are not associated with any substantial alterations in blood pressure. In children aged 6 to 10, there is a linear decrease in blood pressure that will reach a plateau at approximately a 30% decrease in those beyond the age of 10. Conversely, younger children require no additional precautions.

Bupivacaine, has a narrow therapeutic index in children, and its dosing requires careful consideration to strike a balance between effective anesthesia and the risk of toxicity. The traditional method of dosing bupivacaine in pediatric spinal anesthesia is based on the child's body weight. This weight-based dosing considers the assumption that children's drug clearance correlates with their body mass. However, this approach might not account for the maturational changes in drug handling by pediatric patients or the variability in spinal column length and cerebrospinal fluid volumes, not always proportional to weight but may evolve with age.

Emerging evidence suggests that age-based dosing may be more effective. It hypothesizes that developmental pharmacokinetics, including changes in body composition, organ function, and drug-receptor differences, can influence bupivacaine metabolism and action more significantly than body mass alone. By accounting for the age-related anatomical and physiological changes, age-based dosing could result in more precise and effective anesthesia with a decreased risk of adverse outcomes.

To the authors knowledge, there is no study comparing age-based and weight-based bupivacaine dosing for pediatric spinal anesthesia in children undergoing elective infra-umbilical surgery.

Study Overview

• Status: Not yet recruiting
• Conditions: Spinal Anesthesia; Local Anesthetic; Bupivacaine
• Intervention / Treatment: Drug: Weight-based dosing; Drug: Age-based dosing

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Kareem MA Nawwar, M.D.; Phone Number: +201003878369; Email: drknawwar@cu.edu.eg

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• ASA I and II
• Both genders
• Elective infra-umbilical surgeries with anticipated duration ≤ 90 minutes.

Exclusion Criteria:

• Guardian refusal.
• Children with major congenital heart disease, including septal defects.
• Patients with neuromuscular disorders or high intracranial pressure.
• Children with spinal deformities or morbid obesity (BMI above the 99th percentile).
• Children with a history or family history of coagulation disorders.
• Children with local infection at the site of skin puncture for spinal anesthesia.
• Children with known allergy to bupivacaine.
• Surgeries requiring head down (Trendelenburg) or prone position.
• Unexpected prolongation of surgery > 90 minutes.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Weight-based dosing; Hyperbaric bupivacaine 0.5% dosage will be calculated and administered intrathecally as 0.4 mg/kg or 0.08 ml/kg if body weight ≤ 15 kg and 0.3 mg/kg or 0.06 ml/kg if body weight > 15 kg	Drug: Weight-based dosing; Hyperbaric bupivacaine 0.5% dosage will be calculated and administered intrathecally as 0.4 mg/kg or 0.08 ml/kg if body weight ≤ 15 kg and 0.3 mg/kg or 0.06 ml/kg if body weight > 15 kg
Active Comparator: Age-based dosing group; Hyperbaric bupivacaine 0.5% will be administered at the dose of age divided by 5 (in ml). The age in months after the completion of a year was noted and considered as the next age if it is more than 6 months and the same age if it is ≤ 6 months.	Drug: Age-based dosing; Hyperbaric bupivacaine 0.5% will be administered at the dose of age divided by 5 (in ml). The age in months after the completion of a year was noted and considered as the next age if it is more than 6 months and the same age if it is ≤ 6 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The peak sensory level	The sensory level of subarachnoid block, tested by firm skin pinch.	5 mins after intrathecal bupivacaine injection

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Block level time	Time from injection of local anesthetic intrathecally to achieving full motor and adequate sensory block	10 minutes from intrathecal injection of local anesthetic
Duration of the block	Duration from intrathecal injection of local anesthetic till return of motor power of the lower limbs	120 minutes from intrathecal injection of local anesthetic
Postoperative pain score	Postoperative pain levels using the Face, Legs, Activity, Cry, and Consolability (FLACC) scale	3 hours from intrathecal injection of local anesthetic
Incidence of failed spinal blocks	Percentage of failed spinal blocks requiring conversion to general anesthesia	2 hours from attempting subarachnoid block application

Collaborators and Investigators

• Sponsor: Cairo University
• Investigators: Study Director: Kareem MA Nawwar, M.D., Cairo University; Study Chair: Manal M Elgohary, M.D., Cairo University; Study Director: Hany M Elhady, M.D., Cairo University; Principal Investigator: Bassant A Heikal, M.B.B.Ch., Cairo University

Study record dates

Study Major Dates

• Study Start (Estimated): January 30, 2025
• Primary Completion (Estimated): May 30, 2025
• Study Completion (Estimated): June 5, 2025

Study Registration Dates

• First Submitted: January 25, 2025
• First Submitted That Met QC Criteria: January 25, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: January 25, 2025
• Last Verified: January 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: MS-503-2024

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No