{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,12]],"date-time":"2026-09-12T11:46:54Z","timestamp":1789213614877,"version":"build-2803163510"},"reference-count":17,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,12,11]],"date-time":"2020-12-11T00:00:00Z","timestamp":1607644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Background: The trigeminocardiac reflex (TCR) is a brainstem reflex following stimulation of the trigeminal nerve, resulting in bradycardia, asystole and hypotension. It has been described in maxillofacial and craniofacial surgeries. This case series highlights TCR events occurring during sphenopalatine ganglion (SPJ) neurostimulator implantation as part of the Pathway CH-2 clinical trial \u201cSphenopalatine ganglion Stimulation for Treatment of Chronic Cluster Headache\u201d. Methods: This is a case series discussing sphenopalatine ganglion neurostimulator implantation in the pterygopalatine fossa as treatment for intractable cluster headaches. Eight cases are discussed with three demonstrating TCR events. All cases received remifentanil and desflurane for anesthetic maintenance. Results: Each patient with a TCR event experienced severe bradycardia. In two cases, TCR resolved with removal of the introducer, while the third case\u2019s TCR event resolved with both anticholinergic treatment and surgical stimulation cessation. Conclusion: Each TCR event occurred before stimulation of the fixed introducer device, suggesting the cause for the TCR events was mechanical in origin. Due to heightened concern for further TCR events, all subsequent cases had pre-anesthesia external pacing pads placed. Resolution can occur with cessation of surgical manipulation and\/or anticholinergic treatment. Management of TCR events requires communication between surgical teams and anesthesia providers, especially during sphenopalatine ganglion implantation when maxillary nerve stimulation is possible.<\/jats:p>","DOI":"10.3390\/brainsci10120973","type":"journal-article","created":{"date-parts":[[2020,12,13]],"date-time":"2020-12-13T20:56:57Z","timestamp":1607893017000},"page":"973","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Trigeminocardiac Reflex Induced by Maxillary Nerve Stimulation during Sphenopalatine Ganglion Implantation: A Case Series"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5122-3771","authenticated-orcid":false,"given":"Yousef","family":"Hammad","sequence":"first","affiliation":[{"name":"Department of Oral &amp; Maxillofacial Surgery, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Allison","family":"Mootz","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Pain Management, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3664-8266","authenticated-orcid":false,"given":"Kevin","family":"Klein","sequence":"additional","affiliation":[{"name":"Departments of Anesthesiology &amp; Pain Management and Otolaryngology, Head &amp; Neck Surgery, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John R.","family":"Zuniga","sequence":"additional","affiliation":[{"name":"Departments of Oral &amp; Maxillofacial Surgery and Neurology, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"71","DOI":"10.4103\/jnacc-jnacc-24.17","article-title":"Brain and heart connections: The trigeminocardiac reflex!","volume":"4","author":"Singh","year":"2017","journal-title":"J Neuroanaesth. Crit. Care"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"184","DOI":"10.1016\/j.tripleo.2009.03.050","article-title":"Trigeminocardiac reflex: A MaxFax literature review","volume":"108","author":"Bohluli","year":"2009","journal-title":"Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"727","DOI":"10.1007\/s00701-005-0535-1","article-title":"Trigeminocardiac reflex during skull base surgery: Mechanism and management","volume":"147","author":"Koerbel","year":"2005","journal-title":"Acta Neurochir."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1097\/ANA.0b013e3181a2bf22","article-title":"Trigemino-Cardiac Reflex Examination Group (TCREG). The Trigemino-cardiac Reflex: An Update of the Current Knowledge","volume":"21","author":"Schaller","year":"2009","journal-title":"J Neurosurg. 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Neurosurg."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"745","DOI":"10.1227\/00006123-198812000-00010","article-title":"Trigeminal depressor response during percutaneous microcompression of the trigeminal ganglion for trigeminal neuralgia","volume":"23","author":"Brown","year":"1988","journal-title":"Neurosurgery"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1081","DOI":"10.1016\/S1474-4422(19)30322-9","article-title":"Safety and Efficacy of Sphenopalatine Ganglion Stimulation for Chronic Cluster Headache: A Double-blind, Randomized Controlled Trial","volume":"18","author":"Goadsby","year":"2019","journal-title":"Lancet Neurol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1016\/S1474-4422(02)00104-7","article-title":"Pathophysiology of cluster headache: A trigeminal autonomic cephalgia","volume":"1","author":"Goadsby","year":"2002","journal-title":"Lancet Neurol."}],"container-title":["Brain Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-3425\/10\/12\/973\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:44:02Z","timestamp":1760179442000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-3425\/10\/12\/973"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,12,11]]},"references-count":17,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2020,12]]}},"alternative-id":["brainsci10120973"],"URL":"https:\/\/doi.org\/10.3390\/brainsci10120973","relation":{},"ISSN":["2076-3425"],"issn-type":[{"value":"2076-3425","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,12,11]]}}}