Ear Tube Placement in Kids WITHOUT Sedation (Starting at 12 Months of Age)

A recent report describes how using a relatively old technology, ear tube placement can now be performed in children starting at 12 months of age with chronic ear infections or hearing loss due to fluid buildup without the need for sedation of any kind nor aggressive restraints (ie papoose). Historically, ear tube placement in the office without sedation is typically performed starting at around 12 years of age using standard local anesthesia techniques. Any younger, a child could not be trusted to stay still during the procedure due to presence of some discomfort.

In any case, a Texan ear group reports how they accomplished this simple procedure at such young ages.

First, the ear canal is cleaned as much as possible of all earwax and debris. The ear canal is than filled with an anesthetic liquid (concoction of lidocaine, epinephrine, and sodium bicarbonate). Over 10 minutes, iontophoresis was than used to induce profound local anesthesia to the ear canal and eardrum. The liquid was than suctioned out and ear tube placement was performed with a reported 90% success rate (78 of 86 ears; 17 subjects were 3 years old or younger; 8 were 12 months old).

The key to success required 3 "new" elements.

• Iontophoresis device made by Acclarent. There are other iontophoresis devices in the market (Medtronic and Otomed), but none adapted for simultaneous bilateral ear canal usage that works within 10 minutes. Iontophoresis works by applying a gentle electric current in order to actively move charged drug molecules into the skin. In this particular case, positively charged lidocaine and epinephrine.
• Optimal anesthetic solution for iontophoresis. Dubbed "EMGIM", it contains 1:12,000 epinephrine with 3.3% lidocaine hydrochloride and 0.7% sodium bicarbonate. The solution is prepared fresh prior to use by combining 10 mL of 4% lidocaine hydrochloride with 1 mL of 1:1,000 epinephrine. After mixing the lidocaine and epinephrine, 1 mL of 8.4% sodium bicarbonate is added.
• Ear tube delivery device and placement system. Typically, a competent ENT can place an ear tube in about 10-20 seconds. However, when dealing with kids who may potentially move unexpectedly and operating within a very small ear canal space, a faster and more reliable way of placing a tube was required. Hence, this new device. [link]

Of course, during the actual procedure, age-appropriate distraction was needed to minimize movement, especially given aggressive restraint was not used.

Sounds great as sedation is something to be avoided if at all possible. However, there is one problem... the Acclarent iontophoresis device is NOT yet FDA approved contrary to what the report states (direct communication with Acclarent executives October 1, 2013). Hopefully in 2014. As such, beyond a research setting, this in-office technique is not yet available for use in the United States.

As an aside, there are FDA-approved iontophoresis devices for use in pediatric head and neck surgical procedures mainly for sub-cutaneous mass excisions and abscess incision and drainage. Check out Phoresor for such applications using lidocaine infused electrodes. It's even sold on Amazon.


References:
Otologic Iontophoresis: A No-Papoose Technique. Annals of Otology. Rhinology & Laryngology 122(8):487-491. Aug 2013.

In-Office Tympanostomy Tube Placement Under Local Anesthesia Using a Novel Tube Delivery Device. Triological Meeting Poster. Dec 2012.

Iontophoresis: a needle-free, electrical system of local anesthesia delivery for pediatric surgical office procedures. J Pediatr Surg. 1999 Jun;34(6):946-9.

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Local Anesthetic Allergy

Rarely, a patient presents with a history of being allergic to lidocaine or another kind of local anesthetic. Often, the "allergic" reaction described (racing heart, light-headed, dizziness, etc) is more attributable to the epinephrine which is often used in conjunction with the anesthetic; therefore not a true allergy, but a not unexpected possible side effect.

Also, if a true allergy is present, it may not be to the anesthetic itself, but the preservative contained within, typically metabisulfite and/or methylparaben. The exception are single-dose vials which are preservative-free, unless they contain epinephrine. Any local anesthetic containing epinephrine, whether a single-dose or multi-dose vial, has metabisulfite in it. The preservative in the multi-dose vial of lidocaine and other anesthetics typically contain methylparaben. As such, the muti-dose vial of lidocaine with epinephrine would contain both metabisulfite and methylparaben.

In any case, if a true allergy to the anesthetic itself is present, there is the possibility that another type of anesthetic can be used. Why?

There are two different classes of local anesthetics divided into amino esters and amino amides. Chemically, amino amides have an amide link between the intermediate chain and the aromatic end, whereas amino esters have an ester link between the intermediate chain and the aromatic end.

Amino Ester

Amino Amide

There are other differences. Pharmacologically, amino esters are metabolized in the plasma whereas amino amides are metabolized in the liver. Amino esters are unstable in solution, but amino amides are very stable in solution.

Amino esters are also much more likely than amino amides to cause allergic hypersensitivity reactions.

Amino Esters (only one "i" in the spelling of the name):

• Cocaine
• Procaine
• Tetracaine (in the form of cetacaine)*
• Chloroprocaine*
• Benzocaine (in the form of cetacaine)*
• Cetacaine (benzocaine and tetracaine)*
• Propoxycaine

Amino Amides (two "i"'s in the spelling of the name):

• Lidocaine*
• Mepivacaine*
• Prilocaine
• Bupivacaine*
• Ropivacaine*
• Levobupivacaine
• Articaine
• Etidocaine
• Trimecaine
• EMLA (lidocaine/prilocaine)

* is next to those commonly carried in hospitals.

Much appreciate the assistance of Margaret Rowe, PharmD who helped write this blog article.

Source:
Local Anesthetics. Emedicine 4/19/13

Local Anesthetic. Wikipedia

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