Block of the Sphenopalatine Nerve Ganglion for Postoperative Analgesia in Transsphenoidal Approaches: a Prospective, Randomized and Double-blind Study

Transsphenoidal surgery is considered safe and effective and is currently the procedure of choice for the removal of intrasellar lesions. Direct transnasal access to the sphenoid sinus, without the need for detachment of the nasal septum, provides less postoperative morbidity compared to traditional methods. Sphenopalatine ganglion block is known for its efficacy in otorhinolaryngological surgeries in which the sinuses are approached by transnasal endoscopy, as an important part of postoperative analgesia. However, in a neurosurgical environment, specifically in the treatment of tumors of the sella turcica, the use of the blockade of the referred ganglion to produce postoperative analgesia has been used in a scarce way in the literature. The primary objective of the study is to verify whether blocking the sphenopalatine nerve ganglion in the nasopharynx posterior wall provides better postoperative pain control in surgeries with nasal access for transsphenoidal approach, compared to the placebo group. As secondary objectives, the investigators will observe the consumption of opioids in the intraoperative period, in addition to the incidence of nausea, vomiting and postoperative headache also within 24 hours. Forty patients with physical status P1, P2 or P3 will be prospectively analyzed by the American Society of Anesthesiology (ASA) to undergo microsurgery for tumors with a sellar and / or suprasellar location, with transsphenoidal access, in patients with an age range between 18 and 64 years old, including men and women. As for the surgical technique, both the use of the microscope and the endoscope will be considered. They will be randomly allocated to a placebo group (group P; 0.9% saline, n = 20) and a test group (group R; ropivacaine 1%, n = 20).