Dexmedetomidine Use in SZMN Blocks for Pediatric T&A Pain Control

Dexmedetomidine Use in Suprazygomatic Maxillary Nerve Blocks for Pediatric Adenotonsillectomy Pain Control

The suprazygomatic maxillary nerve (SZMN) block is a well-established, safe and effective regional technique for pain management following cleft palate procedures. However, it has not been studied for patients undergoing tonsillectomy and adenoidectomy (T&A) procedures. The goal of this study is to determine whether the SZMN block can be utilized to improve pain control and decrease morbidity in pediatric patients undergoing T&A. An additional goal will be to determine whether the use of dexmedetomidine as a local anesthetic adjunct can prolong the analgesic effects of the SZMN block to cover the entire duration of pain experienced.

Patients between 6 months and 18 years undergoing T&A surgical procedures will be reviewed for potential study enrollment. If participants agree to participate, they will be randomized into one of the three groups: the suprazygomatic maxillary nerve (SZMN) block treatment cohort the SZMN block with Dexmedetomidine treatment cohort the control cohort (standard of care). After anesthesia induction, patients randomized into the SZMN-treatment group or SZMN+Dexmedetomidine treatment group will receive bilateral single injection SZMN blocks under general anesthesia in the operating room. Participants enrolled into the control group will receive the standard of care with no changes to their anesthetic or surgical care. This group will not receive the SZMN block. Postoperative pain scores and opioid consumption for all three groups will be collected in the PACU and for each postoperative day for a total of 14 postoperative days. We will also collect the following data: time to discharge readiness, postoperative nausea/vomiting, emergence delirium, oxygen desaturation and respiratory events, ability to tolerate oral intake, bleeding, hospital readmission, and adverse events related to the nerve block.

Suprazygomatic maxillary nerve block, Tonsillectomy and Adenoidectomy, Regional Anesthesia, Dexmedetomidine, Pediatric

Patients in the two intervention groups will receive bilateral suprazygomatic maxillary nerve block such that 5 mL of local anesthetic is deposited on each side. Patients in the SZMN+Dexmedetomidine group will receive Dexmedetomidine in addition to the local anesthetic with placement of the suprazygomatic maxillary nerve block (0.25 mcg/kg on each side for a total dose of 5 mcg/kg, max 20 mcg total).

All three groups will receive a small circular band-aid on their temples (site of suprazygomatic maxillary nerve block placement).

Patients randomized into the SZMN treatment group will receive bilateral single injection SZMN blocks under general anesthesia in the operating room. The injection will occur through the pterygomaxillary fissure into the pterygomaxillary fossa. Patients will receive 5 ml of local anesthetic per side.

Patients randomized into the SZMN+Dexmedetomidine treatment group will receive bilateral single injection SZMN blocks under general anesthesia in the operating room. The injection will occur through the pterygomaxillary fissure into the pterygomaxillary fossa. Patients will receive 5 ml of local anesthetic along with 0.25 mcg/kg (max 10 mcg) Dexmedetomidine on each side (total of 0.5 mcg/kg, total max 20 mcg).

Patients in this group will receive the standard of care for T&A procedures within the pediatric population.

Post-operative nausea, vomiting, delirium, ability to tolerate oral intake, bleeding, respiratory events, hospital readmission, time to discharge readiness

Inclusion Criteria: Ages 6 months - 18 years Give consent/parental consent to participate in study Patients undergoing tonsillectomy and adenoidectomy Exclusion Criteria: Participants who do not consent or have parental consent Patients who require urgent/emergent intervention Patients who undergo additional combined surgical procedures with separate incisions (in addition to the adenotonsillectomy) Patients with known difficult airway, clinical hemodynamic instability, coagulopathy, chronic pain history, chronic pain medication use, and unrepaired congenital heart disease Patients under age 6 months

Grainger J, Saravanappa N. Local anaesthetic for post-tonsillectomy pain: a systematic review and meta-analysis. Clin Otolaryngol. 2008 Oct;33(5):411-9. doi: 10.1111/j.1749-4486.2008.01815.x.

Chiono J, Raux O, Bringuier S, Sola C, Bigorre M, Capdevila X, Dadure C. Bilateral suprazygomatic maxillary nerve block for cleft palate repair in children: a prospective, randomized, double-blind study versus placebo. Anesthesiology. 2014 Jun;120(6):1362-9. doi: 10.1097/ALN.0000000000000171.