Nerve of Arnold Block for Postoperative Pain

(NOA Trial)

Overseen By Karthik Swamy

Age: < 18

Sex: Any

Trial Phase: Phase 4

Sponsor: University of South Alabama

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: Unknown

What You Need to Know Before You Apply

What is the purpose of this trial?

Background: Bilateral myringotomy with tympanostomy tube (BMT) placement is one of the most common pediatric surgical procedures. Despite its brief duration, many children experience significant postoperative pain. Current standard care typically involves intramuscular (IM) administration of an opioid (fentanyl) combined with a non-steroidal anti-inflammatory drug (ketorolac). While this multimodal approach provides adequate pain control for approximately 75% of children, it is associated with opioid-related side effects including respiratory depression, nausea, vomiting, and sedation. Additionally, nearly one-quarter of children still experience moderate-to-severe pain despite this regimen.

The Nerve of Arnold block is a regional anesthesia technique that involves injection of local anesthetic near the auricular branch of the vagus nerve, which provides sensory innervation to the external auditory canal and tympanic membrane. This technique offers the potential for targeted, opioid-sparing analgesia with extended duration and minimal systemic side effects. However, high-quality evidence comparing this regional technique to standard systemic analgesia in pediatric patients is lacking.

Study Objective: This study aims to determine whether the Nerve of Arnold block is non-inferior to the standard combination of IM fentanyl and IM ketorolac in controlling postoperative pain in children undergoing BMT placement.

Study Design: This is a prospective, randomized, double-blind, non-inferiority trial. Three hundred children aged 6 months to 6 years scheduled for bilateral myringotomy with tympanostomy tube placement will be randomized 1:1 to receive either: (1) Standard care: IM fentanyl (1-2 mcg/kg) plus IM ketorolac (0.5 mg/kg) with sham Nerve of Arnold block, or (2) Intervention: Bilateral Nerve of Arnold block with bupivacaine 0.25% plus sham IM injections. Both patients and outcome assessors will be blinded to treatment assignments.

Primary Outcome: The proportion of patients experiencing moderate-to-severe pain (Face, Legs, Activity, Cry, Consolability \[FLACC\] scale score ≥4) in the Post-Anesthesia Care Unit (PACU). Non-inferiority will be declared if the upper bound of the 95% confidence interval for the difference in proportions is less than 10 percentage points.

Secondary Outcomes: Secondary outcomes include mean and maximum FLACC scores, rescue analgesic requirements, respiratory depression, postoperative nausea and vomiting, PACU length of stay, parent satisfaction, and pain at 24 hours postoperatively.

Clinical Significance: If the Nerve of Arnold block is shown to be non-inferior to standard care, it could provide a valuable opioid-sparing alternative for postoperative pain management in pediatric ear surgery, potentially reducing opioid-related adverse events while maintaining effective analgesia. This would be particularly beneficial for patients with contraindications to opioids or NSAIDs and aligns with national efforts to reduce opioid exposure in pediatric populations.

Are You a Good Fit for This Trial?

This trial is for children aged 6 months to 6 years undergoing ear surgery (BMT placement). It's not specified who can't join, but typically those with allergies or conditions that could interfere with the study might be excluded.

Inclusion Criteria

I am between 6 months and 6 years old.

I am scheduled for ear tube surgery in both ears.

ASA physical status I-II

Exclusion Criteria

My procedure will be on one side only.

I am not allergic to fentanyl, ketorolac, or bupivacaine.

I have a bleeding disorder or I am on blood thinners.

What Are the Treatments Tested in This Trial?

Interventions

• Nerve of Arnold Block

Trial Overview The trial compares a standard pain relief method using fentanyl and ketorolac injections against a regional anesthesia technique called Nerve of Arnold block. The goal is to see if the nerve block controls pain just as well without opioid side effects.

How Is the Trial Designed?

Group I: Nerve block arm Experimental Treatment 4 Interventions

Patients receive bilateral Nerve of Arnold block with bupivacaine 0.25% with epinephrine 1:200,000 (0.2 mL per side) plus dexmedetomidine 5 mcg per side (maximum total bupivacaine dose 2.5 mg/kg) after induction of anesthesia. sham intramuscular injection with normal saline is performed to maintain blinding.

Group II: IM Arm standard Care Active Control 3 Interventions

Patients receive intramuscular fentanyl 2 mcg/kg (maximum 100 mcg) plus intramuscular ketorolac 0.5 mg/kg (maximum 30 mg) after induction of anesthesia. Sham bilateral Nerve of Arnold block with normal saline 0.2 mL per side is performed to maintain blinding.

Who Is Running the Clinical Trial?

University of South Alabama

Lead Sponsor

Trials

44

Recruited

15,800+