A Phase 4 interventional study of Sphenopalatine ganglion block (Ropivacaine) and Sham sphenopalatine ganglion block (Saline) in Postoperative Pain, Tonsillectomy and Adenotonsillectomy, sponsored by Vinícius C Quintão, MD, MSc, PhD. Not yet recruiting. Open to participants aged 2 Years to 13 Years. Per ClinicalTrials.gov, last updated 2026-08-28.
Sponsored by Vinícius C Quintão, MD, MSc, PhD · Phase 4, Interventional, and Treatment
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:
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.
5,640 studies on the registry are indexed under Pain, Postoperative; 1,230 are open to participants now.
This study's planned enrollment of 145 is above the median of 75 across 4,821 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →Vinícius C Quintão, MD, MSc, PhD is the lead sponsor of 3 studies on the registry; 2 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Intraoperative sphenopalatine ganglion block performed after anesthetic induction and orotracheal intubation, before the start of surgery, with a swab and 1% ropivacaine, maximum 10 mg.
Drug: Sphenopalatine ganglion block (Ropivacaine)
Sham intraoperative sphenopalatine ganglion block performed after anesthetic induction and orotracheal intubation, before the start of surgery, with a swab and saline.
Drug: Sham sphenopalatine ganglion block (Saline)
Following induction of general anesthesia and orotracheal intubation, prior to the start of surgery, the study intervention will be performed. The patient will be in a supine position with the neck extended. Extension can be facilitated with a pillow or a folded sheet under both shoulders. A long applicator with a cotton swab at the tip is soaked with ropivacaine 1% anesthetic (maximum dose 10 mg). It is then inserted parallel to the floor of the nose until resistance is felt. The swab will be positioned at the posterior pharyngeal wall superior to the middle turbinate. The applicator will be retained in the nostril for 5-10 minutes and then removed. The procedure is repeated similarly in the other nostril. The swab does not come into direct contact with the ganglion, but the local anesthetic infiltrates the surrounding tissue. The connective tissue and mucous membrane covering the ganglion facilitate the spread and penetration of the drug.
Following induction of general anesthesia and orotracheal intubation, prior to the start of surgery, the study intervention will be performed. The patient will be in a supine position with the neck extended. Extension can be facilitated with a pillow or a folded sheet under both shoulders. A long applicator with a cotton swab at the tip is soaked with Saline (sham block). It is then inserted parallel to the floor of the nose until resistance is felt. The swab will be positioned at the posterior pharyngeal wall superior to the middle turbinate. The applicator will be retained in the nostril for 5-10 minutes and then removed. The procedure is repeated in the same manner in the other nostril. The swab does not come into direct contact with the ganglion, but the saline infiltrates the surrounding tissue. The connective tissue and mucous membrane covering it facilitate the spread and penetration of the saline.
Incidence of postoperative pain in the Post-Anesthesia Care Unit (PACU) after adenotonsillectomy
Comparison of the incidence of immediate postoperative pain in the PACU between children who received sphenopalatine ganglion block (SPGB) with ropivacaine 1% and children who received sham block (0.9% NaCl). Pain will be measured using the highest pain score recorded in the PACU, using an age-appropriate scale: * \< 4 years: Revised FLACC Scale * \> 4 and \< 6 years: Revised FACES Scale * ≥ 6 years: Numeric Rating Scale (NRS) A score ≥ 4 on any of these scales will be considered as presence of pain. The analysis will compare the proportion of patients with pain (score ≥4) between the two groups, with estimation of the risk difference and 95% confidence interval.
Time frame: From admission to the PACU until PACU discharge, assessed at admission and every 20 minutes, up to an estimated 60 minutes
Use of rescue opioids and/or analgesics in the PACU (Post-Anesthesia Care Unit)
Use of rescue opioids and/or analgesics in the PACU (Post-Anesthesia Care Unit): yes or no.
Time frame: From admission to the PACU until PACU discharge, up to an estimated 60 minutes
Use of rescue opioids and/or analgesics at the time of hospital discharge
Use of rescue opioids and/or analgesics at the time of hospital discharge: yes or no.
Time frame: At hospital discharge, assessed up to an estimated 24 hours after surgery
Postoperative pain at the time of hospital discharge
Postoperative pain at the time of hospital discharge: yes or no.
Time frame: At hospital discharge, assessed up to an estimated 24 hours after surgery
Nausea and vomiting in the PACU
Nausea and vomiting in the PACU? yes or no.
Time frame: From admission to the PACU until PACU discharge, up to an estimated 60 minutes
Nausea and vomiting at the time of hospital discharge
Nausea and vomiting at the time of hospital discharge: yes or no.
Time frame: At hospital discharge, assessed up to an estimated 24 hours after surgery
Consumption of rescue antiemetics in the PACU
Consumption of rescue antiemetics in the PACU: yes or no.
Time frame: From admission to the PACU until PACU discharge, up to an estimated 60 minutes
Consumption of rescue antiemetics at the time of hospital discharge
Consumption of rescue antiemetics at the time of hospital discharge: yes or no.
Time frame: At hospital discharge, assessed up to an estimated 24 hours after surgery
Intraoperative bleeding
Surgeon's opinion on perioperative bleeding: very reduced, reduced, usual, increased, or very increased.
Time frame: Assessed intraoperatively, at the end of the surgical procedure
Postoperative bleeding
Postoperative bleeding: yes or no The surgeon will inform you if bleeding resulting from the surgical procedure occurs up to 30 days after the surgery.
Time frame: From the end of surgery up to 30 days after surgery
Surgical reintervention
Surgical reintervention: yes or no Need for surgical re-intervention.
Time frame: From the end of surgery up to 30 days after surgery
Medical consultations outside the scheduled
Medical consultations outside the scheduled postoperative control due to complications within the first 30 days of surgery: 1. Consultations only. 2. Readmission for observation. 12. Critical perioperative respiratory events: laryngospasm, stridor, bronchial aspiration, hypoxia (O2 saturation \< 90% for 2 minutes), use of supplemental oxygen in the PACU.
Time frame: From the end of surgery up to 30 days after surgery
Morbidity in the first 30 days after surgery
Morbidity in the first 30 days after surgery: admission to intensive care unit or ICU, readmission due to: NGO infection, dehydration, pulmonary infection, pulmonary complications, seizure.
Time frame: From the end of surgery up to 30 days after surgery
Mortality in the first 30 days after surgery
Mortality: yes or no
Time frame: From the end of surgery up to 30 days after surgery
No study locations are listed for this record.
Plan to share: No
Start is estimated for Sep 2026; primary completion for Aug 2028, 23 months later.
Of 531 non-industry phase 4 interventional studies under Pain, Postoperative, half reached primary completion within 16 months of starting (the median), counting those still running; a quarter within 8 and three quarters within 32. This study's planned 23 months is above that.
Counting every sponsor, half of 541 studies reached it within 16 months; a quarter within 8 and three quarters within 32.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Ropivacaine
Vinícius C Quintão, MD, MSc, PhD