title: Imidazoline use in sinonasal surgery.
abstract: The nasal mucosa is very vascular, receiving more blood flow per cubic centimeter of tissue than does muscle, brain or liver (Drettner and Aust, 1974; [1]). This vascularity can present a major problem during sinus surgery. Surgeons routinely use topical vasoconstrictors in endoscopic sinus surgery however, the optimal regimen is not clear. Imidazoline nasal sprays are often used up to 1hour before sinonasal surgery to aid in intraoperative vasoconstriction. After the induction of anaesthesia, epinephrine-based topical and submucosal preparations are subsequently administered to further enhance vasoconstriction. Imidazolines are non-selective, partial alpha adrenoceptor agonists with a higher affinity, yet lower potency, for alpha adrenoceptors when compared to epinephrine. It is hypothesized that imidazolines block the action of epinephrine on the alpha adrenoceptors of the nasal mucosa resulting in less vasoconstriction, and a poorer intra-operative field, when compared to the use of epinephrine alone. This paper hypothesizes that preoperative imidazoline administration may adversely affect optimal intra-operative vasoconstriction.
authors.affiliation: North Shore Hospital, Waitemata District Health Board, Auckland, New Zealand.
authors.forename: R G
authors.initials: RG
authors.lastname: Campbell
authors.affiliation: Auckland City Hospital, Auckland District Health Board, Auckland, New Zealand.
authors.forename: S
authors.initials: S
authors.lastname: Nair
authors.affiliation: Macquarie University and the University of Sydney, Australia.
authors.forename: R
authors.initials: R
authors.lastname: Sacks
authors.affiliation: Department of Surgery, The University of Auckland, New Zealand. Electronic address: richard.douglas@auckland.ac.nz.
authors.forename: R G
authors.initials: RG
authors.lastname: Douglas
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D004837:Epinephrine / Q000037:antagonists & inhibitors; D006801:Humans; D048288:Imidazolines / Q000009:adverse effects / Q000494:pharmacology*; D008954:Models, Biological; D009297:Nasal Mucosa / Q000098:blood supply* / Q000601:surgery; D010256:Paranasal Sinuses / Q000601:surgery*; D014661:Vasoconstriction / Q000187:drug effects*
chemical_list: D000316:Adrenergic alpha-Agonists; D048288:Imidazolines; D004837:Epinephrine