Pressure equalization (PE) tube placement is one of the most commonly performed surgical procedures, and purulent drainage through the tube is the most common complication of tube insertion. Fortunately, drainage usually quickly resolves with initial treatment. Occasionally, drainage persists and requires more aggressive therapy, including tube removal or chronic ear surgery (tympanomastoidectomy). Because management of acute and chronic drainage is distinctly different, discussion is divided into these two categories. In this chapter, acute drainage refers to new drainage, rather than a specific duration. Chronic drainage refers to persistent drainage after initial treatment has failed.
Acute Drainage
Frequently, the cause of acute drainage is either a recent viral upper respiratory infection (URI) or water contamination into the ear canal. Of these two, viral URI is far more common because a small amount of water in the canal is rarely harmful. Note that most URIs are viral whereas most middle ear drainage is bacterial. It is well known that acute bacterial otitis media most often results from a viral URI, usually within 2 weeks of onset. Inflammation and swelling of the eustachian tube and middle ear mucosa impair the protective mucociliary clearance and aeration of the middle ear, encouraging bacterial infection. In the same way, viral URI can initiate bacterial puru-lent discharge through a PE tube. The point is that drainage through a PE tube is presumed bacterial, even though it often results from a viral URI. The bacteria are similar to those of acute otitis media: Streptococcus pneumoniae, Hemophilus influenzae, and Moraxella catarrhalis. Treatment consists of broad-spectrum oral antibiotics such as amoxicillin (Amoxil) 40 mg kg day, amoxicillin-clavulanate (Augmentin) 40 mg kg day, cefpodoxime (Vantin) 10 mg kg day, or clarithromycin (Biaxin) 15 mg kg day for 10 days. The patient is instructed to keep water out of the ear (dry ear precautions).
Although water contamination of the middle ear through the canal and tube is usually harmless, it occasionally causes inflammation and bacterial discharge. If the history suggests water contamination, topical antibiotics alone often are sufficient to treat infection. Polymyxin–neomycin–hydrocortisone (Cortisporin, Colymycin) or a similar suspension is given in 3 drops tid, left in the ear each time for 5 min. A 5-day course of treatment is usually sufficient.
When the history suggests neither water contamination nor viral URI, often both a topical and an oral antibiotic are given for 10 days. A routine culture of the drainage at this point is not needed because infection usually clears quickly with this simple combined treatment.
Chronic Drainage
After topical or oral antibiotics, or both, have been given for initial treatment, the patient is reexamined at 10 days. If drainage is greatly improved but not yet resolved, the same antibiotics can be continued for another 10 days. However, if drainage is no better, several causative factors must be considered.
First, chronic drainage can persist because the bacteria are resistant to the antibiotic. Frequently this implies that the infection is caused by Pseudomonas aeruginosa, which is resistant to all oral antibiotics except ciprofloxacin. Moreover, even though most topical antibiotics will cover Pseudomonas, sometimes drainage is so profuse that the drop cannot penetrate the tube to the middle ear. If the ear is still draining without improvement after initial antibiotic treatment, the drainage should be cultured to determine whether Pseudomonas infection is present. Preliminary results often are known in 36 h.
