Myringotomy and Tympanostomy Tube Insertion (BMT)
Surgical drainage of middle year fluid is indicated for failure of medical management in young infants and children. It is often accompanied by viral or bacterial upper respiratory tract infection’s (URI’s) and inflammation of the middle year. If left untreated it may result in conductive hearing loss. Simple myringotomy once healed may lead to recurrence, therefore a ventilating tube is often placed allowing for continuous drainage till the tube is extruded in 6–12 months. Children with cleft palate almost always require BMT at the time of repair of the cleft. In some instances, surgical removal of retained ventilating tube is necessary along with a patch or fat graft. Uncomplicated mild URI does not pose additional risks provided endotracheal intubation is avoided.
B. Anesthetic Considerations
BMT procedure is brief and is usually carried out using inhalation anesthesia with sevoflurane and nitrous oxide in oxygen via a facemask and spontaneous ventilation. Nitrous oxide is often used to hasten induction. However, benefits of its use during maintenance of anesthesia (diffusion into middle year cavity and bulging of tympanic membrane) must be weighed against its con of OR pollution and exposure to operating room personnel. An oral airway is usually placed to maintain airway patency, ventilation, and depth of anesthesia. Assisted ventilation and continuous positive airway pressure (CPAP) may be necessary in the very young infants to maintain airway patency. An intravenous (IV) placement is usually not necessary but an IV set with fluid should be available.
Pain and discomfort following the procedure is managed with intramuscular ketorolac or oral or rectal acetaminophen. Acetaminophen with codeine (black box warning) or hydrocodone (better tasting) have been found to be superior to plain acetaminophen. Intranasal fentanyl or dexmedetomidine are useful in providing additional pain relief and reducing emergence excitement from sevoflurane anesthesia. Oral midazolam is useful for very anxious children but its use may have unwanted side effects of emergence delirium or prolonged sedation.
Middle Ear, Outer Ear, and Mastoid Surgery
Persistent nonhealing of tympanic membrane may result in middle year perforation requiring tympanoplasty with a patch or fat graft. Ossicular chain reconstruction is often necessary. Persistent otitis media often leads to mastoiditis and formation of a cholesteatoma (invasive growth of keratinizing squamous epithelium) requiring mastoidectomy and reestablishing middle year ventilation. Stapedectomy is performed to treat otosclerosis. Inner ear procedures include surgery to the cochlear implant, endolymphatic sac, and the labyrinth. Outer ear procedures may be performed to correct congenital or acquired ear malformations. Patients with Goldenhar or Treachers Collins syndromes frequently pose airway challenges. Ear procedures, particularly inner ear procedures, are prone to postoperative nausea and vomiting.
B. Anesthetic Considerations