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Introduction

Endoscopic sinus surgery (ESS) is one of the most common surgical procedures performed by otolaryngologists. This minimally invasive technique is commonly used to restore sinus ventilation and function in patients with chronic sinusitis and nasal polyps for whom medical therapy has failed . In the procedure, sinus air cells and sinus ostia are opened under direct visualization with the intent to restore normal mucociliary drainage. The main advantage of ESS as compared to conventional procedures is its less invasive nature, which results in less post-operative discomfort, provides better visualization, and thereby reduces complications . The clinical outcomes after ESS are generally favorable, with success rates between 80% and 90% (i.e. majority of the patient’s symptoms resolved) .

Endoscopic sinus surgery can be difficult because of the complex anatomy and proximity of vital structures such as the intracranial and intraorbital compartments. The presence of nasal polyps may also contribute to the challenges encountered in this area, as they obscure the visual field and have been associated with increased intraoperative blood loss. During ESS, the narrow confines of the surgical field can easily become obscured by small amounts of bleeding. Thus, in order to achieve optimal visualization, reduce complication, decrease operation time (OT), and improve outcomes, it is most beneficial to minimize bleeding during surgery.

Traditionally, local anesthesia in ESS has consisted of one of the following: cotton-tip application of powdered cocaine (100–150 mg/side) to the nasal mucosa, transnasal injection of 1% lidocaine with 1:100,000 epinephrine, or transoral sphenopalatine block via the greater palatine canal (GPC) . In addition to their anesthetic effects, these methods can help to decrease bleeding in the operative field by causing hemostasis through a variety of mechanisms, including epinephrine-induced vasoconstriction, mechanical tamponade of the vessels, and a parasympathetic block allowing unopposed sympathetic activity .

The modern technique for GPC injection, where the needle is bent at a 45° angle and advanced 25 to 28 mm once inside the foramen, was described in 1988 by Stankiewicz . This was later reaffirmed by Douglass and Wormald in 2006 . To date, only one study has been published that evaluates the role of GPC injection in ESS. Wormald et al. have shown that transoral injection of the GPC with 2% lidocaine and 1:80,000 epinephrine improves visualization during ESS . The effects of GPC injection on quantitative blood loss in ESS, however, have yet to be described. In our study, we compare the estimated blood loss (EBL) during ESS between patients receiving transoral GPC and transnasal (TN) infiltration (combined) to patients receiving only TN infiltration.