Sphenopalatine Ganglion Block for Pain Relief After Pediatric Adenotonsillectomy

Effect of Sphenopalatine Ganglion Block for Postoperative Pain Control After Adenotonsillectomy in Children

The aim of this clinical trial is to discover whether sphenopalatine ganglion block (SPGB) reduces postoperative pain in children aged 2 to 13 years undergoing tonsil surgery (with or without adenoid removal).

The main questions it aims to answer are:

• Does SPGB reduce postoperative pain in children undergoing throat surgery?
• Do children who receive SPGB require less pain medication after surgery?
• Do children who receive SPGB experience less nausea and vomiting after surgery?
• Do children who receive SPGB experience less bleeding during and after surgery?
• Do children who received SPGB experience fewer complications after surgery?

Researchers will perform SPGB after the child has been placed under general anesthesia, before the surgeon begins the tonsil surgery. Each child will be randomly assigned to receive the SPGB with either a local anesthetic (ropivacaine) or a placebo (saline solution, which looks the same but contains no active medication). This allows researchers to compare pain outcomes between the two groups.

To perform the SPGB, a long cotton-tipped applicator soaked in either the anesthetic or the saline solution is gently placed in each of the child's nostrils and left in place for 5-10 minutes before being removed.

Tonsillectomy, with or without adenoidectomy, is one of the most common surgical procedures performed in children. Despite being frequent, it is associated with significant postoperative morbidity, particularly severe pain, postoperative nausea and vomiting, and bleeding. Current pain management relies heavily on opioids and nonsteroidal anti-inflammatory drugs, both of which carry risks in this population: opioids are associated with respiratory depression, of particular concern in children with obstructive sleep apnea, and increased postoperative nausea and vomiting, while NSAIDs raise concerns about postoperative bleeding.

The sphenopalatine ganglion block is a simple, minimally invasive technique that has shown promising analgesic effects in adults undergoing sinonasal and other otorhinolaryngologic surgeries, with evidence suggesting reduced postoperative pain, reduced opioid consumption, and reduced intraoperative bleeding. However, evidence supporting the safe and effective use of sphenopalatine ganglion block specifically in children undergoing adenotonsillectomy remains limited.

This study is designed to evaluate whether sphenopalatine ganglion block reduces postoperative pain compared with a sham block in children undergoing tonsillectomy or tonsillotomy, with or without adenoidectomy, for indications such as obstructive sleep apnea or recurrent tonsillitis.

Eligible participants will be randomized 1:1 using a web-based block randomization system managed by a person external to the clinical team. An unblinded team member, not otherwise involved in the child's anesthetic or surgical care, will prepare the study medication (ropivacaine or saline) according to the randomization result. All other members of the clinical and research team, as well as the participants and their families, will remain blinded to group allocation.

Based on an alpha of 0.05, a statistical power of 95%, and a medium effect size (Cramer's V = 0.3 for the chi-square test; d = 0.6 for the Mann-Whitney test), a total sample size of 145 participants was determined to provide adequate power for both the primary and key secondary outcomes.

This is the first randomized clinical trial to evaluate the effect of sphenopalatine ganglion block specifically on postoperative pain control after adenotonsillectomy in children, and its findings are intended to help inform evidence-based perioperative pain management guidelines for this common pediatric surgical population.

Inclusion Criteria:

• Children aged 2 to 13 years admitted for tonsillectomy/tonsillotomy with or without adenoidectomy;
• Patients classified as Physical Status I and II according to the American Society of Anesthesiologists (ASA);
• Otolaryngologists responsible for the patient according to the study and willing to report the data necessary for this study.

Exclusion Criteria:

• Children with hypersensitivity or allergy to the drugs used in the study protocol for AG and/or BGEP;
• Use of concomitant medications for anesthesia or pain control that are not in the study protocol in the pre or intraoperative period;
• Children with a history of chronic orofacial pain;
• Failure to provide written Informed Consent Form (ICF) or Informed Assent form (IAF) to participate in the study.