![]() The patient may require anesthesia of the EAC. Do not place the patient with the affected ear facing up, as this may cause the foreign body to move farther into the EAC. 3 Place the patient supine with their face toward the ceiling. 3 Smaller children can be swaddled in a papoose made from a sheet and tape or a commercial immobilization device. The parent or attendant should wrap one arm around the child's arms and body while stabilizing the head with their other arm. Children can sit on the lap of a parent or attendant with the affected ear facing the Emergency Physician. The most convenient position for adult patients is to remain seated with the affected ear facing the Emergency Physician. Warn the patient that they may experience an occasional loud noise, especially if suction is used. Discuss the importance of remaining still during the procedure. The discussion should include discomfort, dizziness, minor bleeding, postprocedural otitis externa, and TM perforation. Otherwise, irrigate the object with alcohol, remove it with instruments, or extract it with suction.Įxplain the procedure and potential complications to the patient and/or their representative. ![]() Irrigation can be attempted if the object is very small and irrigation is expected to rapidly succeed in removal before swelling occurs. 15 Organic foreign bodies will absorb water and swell, making removal more difficult. 1, 15 A relative contraindication for irrigation with water is an organic object, such as a dry bean, seed, or rice. 9, 11, 12 Completely impacted foreign bodies that leave no space for the irrigant fluid to flow behind it will only be driven deeper into the EAC, making subsequent removal even more difficult. Some authors recommend alternate methods for any patient who has never had an ear exam to document the integrity of the TM. 9, 11– 14 Water forced into the middle ear can lead to otitis media, labyrinthitis, mastoiditis, disruption of the ossicles, and loss of balance or hearing. 11 The most important contraindication for irrigating the EAC is an acute or chronically ruptured TM. Irrigation is almost always safe to attempt. 2, 5, 9 These cases are likely to result in injury if the foreign body is removed in the Emergency Department. 3 Finally, objects that are difficult to remove and a patient (usually a young child) who cannot hold still or be held still for the procedure should be referred to an Otolaryngologist. Direct removal will require anesthesia and possibly an approach from outside the EAC to avoid denuding the skin of the EAC. 2, 3, 5, 9 Another contraindication is a large object that has impaled itself in the wall of the EAC. These foreign bodies require removal under general anesthesia with the aid of an operating microscope. ![]() Removal will cause further damage to the TM as well as potential disruption of the middle ear ossicles and loss of hearing. Examples are foreign bodies that have perforated or impaled the TM. The major contraindication to removal in the Emergency Department is probable injury with direct removal. This in turn relies on a Rudnev's point-plane incidence estimate, which in turn relies on Kollár's generalization of the Guth-Katz incidence theorem.Rather than contraindications to removal, these can also be thought of as indications for referral to an Otolaryngologist for removal of the foreign body. The key ingredient in these arguments is recent progress connected to the restriction theory of the finite field paraboloid by Rudnev and Shkredov. While this min-entropy rate is inferior to Chattopadhyay and Zuckerman's construction, our extractors have the advantage of exponential small error which is important in some applications. We give an improved analysis of one of Bourgain's extractors which shows that it in fact extracts from sources with min-entropy rate near $\frac =.477\ldots$, moreover we construct a variant of this extractor which we show extracts from sources with min-entropy rate near $4/9 $ = $.444\ldots$. In the current work, we revisit the Fourier analytic approach. This remained essentially the state of the art until a 2015 breakthrough of Chattopadhyay and Zuckerman in which they gave an alternative approach which produced extractors with arbitrarily small min-entropy rate. His approach combined Fourier analysis with innovative but inefficient tools from arithmetic combinatorics and yielded an unspecified min-entropy rate which was greater than $.499$. In 2005 Bourgain gave the first explicit construction of a two-source extractor family with min-entropy rate less than $1/2$.
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