NASAL & SINUS SURGERY
Common nasal and sinus surgeries include polyp-ectomy, endoscopic sinus surgery, maxillary sinus-otomy (Caldwell–Luc procedure), rhinoplasty, and septoplasty.
Patients undergoing nasal or sinus surgery may have a considerable degree of preoperative nasal obstruc-tion caused by polyps, a deviated septum, or muco-sal congestion from infection. This may make face mask ventilation difficult, particularly if combined with other causes of difficult ventilation (eg, obesity, maxillofacial deformities).
Nasal polyps are often associated with allergic disorders, such as asthma. Patients who also have a history of allergic reactions to aspirin should not be given any nonsteroidal antiinflammatory drugs (including ketorolac) for postoperative analgesia. Nasal polyps are a common feature of cystic fibrosis.
Because of the rich vascular supply of the nasal mucosa, the preoperative interview should concen-trate on questions concerning medication use (eg, aspirin, clopidogrel) and any history of bleeding problems.
Many nasal procedures can be satisfactorily per-formed under local anesthesia with sedation. The anterior ethmoidal nerve and sphenopalatine nerves (Figure 19–3) provide sensory innervation to the nasal septum and lateral walls. Both can be blocked by packing the nose with gauze or cotton-tipped applicators soaked with local anesthetic. The topical anesthetic should be allowed to remain in place at least 10 min before instrumentation is attempted. Supplementation with submucosal injec-tions of local anesthetic is often required. Use of an epinephrine-containing solution or cocaine (usually a 4% or 10% solution) will shrink the nasal mucosa and potentially decrease intraoperative blood loss. Intranasal cocaine (maximum dose, 3 mg/kg) is rap-idly absorbed (reaching peak levels in 30 min) and may be associated with cardiovascular side effects .
General anesthesia is often preferred for nasal surgery because of the discomfort and incom-plete block that may accompany topical anesthesia. Special considerations during and shortly following induction include using an oral airway during face mask ventilation to mitigate the effects of nasal obstruction; intubating with a reinforced or pre-formed Mallinckrodt oral RAE® (Ring–Adair–Elwyn)
endotracheal tube (Figure 36–1); and tucking the patient’s padded arms, with protection of the fingers, to the side. Because of the proximity of the surgical field, it is important to tape the patient’s eyes closed to avoid a corneal abrasion. One exception to this occurs during dissection in endoscopic sinus sur-gery, when the surgeon may wish to periodically check for eye movement because of the close prox-imity of the sinuses and orbit (Figure 37–1); none-theless, the eyes should remain protected until the surgeon is ready to observe them. NMBs are often utilized because of the potential neurological or ophthalmic complications that might arise if the patient moves during sinus instrumentation.Techniques to minimize intraoperative blood loss include supplementation with cocaineor an epinephrine-containing local anesthetic, maintaining a slightly head-up position, and pro-viding a mild degree of controlled hypotension. A posterior pharyngeal pack is often placed to limit the risk of aspiration of blood. Despite these pre-cautions, the anesthesiologist must be prepared for major blood loss, particularly during the resection of vascular tumors (eg, juvenile nasopharyngeal angiofibroma).
Coughing or straining during emergence from anesthesia and extubation should be avoided, as these events will increase venous pressure and increase postoperative bleeding. Unfortunately, rela-tively deep extubation strategies that are commonly and appropriately utilized to accomplish this goal also may increase the risk of aspiration.
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