Address Correspondence to:
Michael E. Pichichero, M.D.
Elmwood Pediatric Group
University of Rochester Medical Center
601 Elmwood Avenue, Box 672
Rochester, NY 14642
(585) 275-1534
FAX: (585) 756-0171
E-mail: Michael_Pichichero@urmc.rochester.edu

In January 1999 a report was issued from the drug resistant Streptococcus pneumoniae Therapeutic Working Group convened by the Centers for Disease Control (1). The objective of the group was to provide consensus recommendations for the management of acute otitis media (AOM). Representatives from the American Academy of Family Physicians, Society for Academic Emergency Medicine, National Foundation of Infectious Diseases, American College of Physicians, World Health Organization Network, American Academy of Otolaryngology- Head and Neck Surgery, American Academy of Pediatrics, Infectious Disease Society of America, National Institutes of Health, Centers for Disease Control and others participated in the discussions.

The consensus document stated "diagnostic tympanocentesis with culture and susceptibility testing of isolates, although difficult to achieve in most practice settings, may be necessary to guide the choice of therapy in difficult AOM cases. Obtaining a culture is particularly important if a child has recently received several courses of antimicrobial therapy and is therefore more likely to harbor a multiple resistant strain. In an era of increasing antimicrobial resistance, clinicians treating children with AOM should consider developing the capacity to perform tympanocentesis themselves or establish a ready referral mechanism to a clinician with this capacity".

Other investigators have advocated tympanocentesis for the child that is highly febrile, toxic, and in acute severe pain (2-5). With these indications for tympanocentesis (myringotomy) it is neither necessary nor appropriate for the child to concomitantly receive insertion of tympanostomy tubes (grommets). The procedure can be safely performed in an office practice setting without the necessity of general anesthesia. Otolaryngologists and properly trained and certified primary care physicians can and should perform the procedure with increasing frequency in an era of rising antibiotic resistant otitis media pathogens. To validate the skill of otolaryngologists and as an intermediate necessary step in the training of primary care physicians, a mannequin model was developed and validated as an effective training tool.
Description of the Mannequin

The mannequin consists of a plastic external shell head and shoulders mold with an external pinnae and auditory canal. The caliber and length and angulation of the external auditory canal are designed to the anatomical specifications simulating a 1-2 year old child. The material is slightly spongy, flesh colored, and moderately resistant to needle puncture.

A cartridge consisting of 4 simulated tympanic membranes inserts into the head portion of the mannequin model. A sliding mechanism produces positioning of the artificial tympanic membrane at an angulation that is anatomically correct. The tympanic membrane is engineered to simulate the appearance and feel of a pop when a tympanocentesis needle or myringotomy knife is used for penetration. Behind the tympanic membrane artificial pus is placed in the inferior portion of the simulated middle ear space. This is recommended as the target for tympanocentesis. The anterior inferior quadrant is suggested as the preferred location (out of concern for safety and the provision of increased depth before the posterial wall the middle ear space is encountered during the aspiration procedure). The superior half of the simulated middle ear space contains a red dye. This is an area of designated avoidance out of concern for possible injury to the malleus, incus or stapes. At a depth of approximately 5 mm a second membrane is present which prevents access to a second chamber containing a blue dye. The depth between the tympanic membrane surface and the second chamber is anatomically correlated with the depth of the middle ear space in a 1-2 year old child. Thus, the trainee is instructed to insert the tympanocentesis needle in the inferior half of the simulated tympanic membrane with preference to the preferred anterior inferior quadrant. The trainee is further advised to avoid the superior half of the tympanic membrane completely. Lastly the trainee is advised that if the tympanocentesis needle is advanced too far, that a blue dye will indicate that event.

Instruction is provided on hand positioning during the procedure. An operating head on a hand held otoscope is used. For this simulation, a 20 gauge, 3 1/2-inch long spinal needle is attached to either a 1 or 3-cc syringe. The needle is bent approximately 1/3 from the hub at a 45-90° in order to allow advancement of the needle via the exterior auditory canal to the tympanic membrane without blockage of visualization through the operating scope magnifying lens. Each tympanic membrane cartridge contains four artificial tympanic membrane/middle ear effusion discs to allow four attempts during the training session.

Each participant is allowed 15 minutes to complete the four tympanocentesis procedures. All participants are evaluated based on their success with each of the four test discs. The scoring system is ten points for a successful procedure (puncture of the inferior half without blue dye securing yellow pus, 5 points for puncture in the anatomically correct inferior half but with blue dye indicating that the needle was advanced too far, (thereby in real life resulting more often in increased bleeding from the periosteum of bone on the posterior middle ear space wall) and minus 5 points for a red dye indicating puncture in the superior portion of the tympanic membrane. Otolaryngologists are also timed as an additional assessment variable. An American Medical Association skill level three continuing education certificate is provided to those who secure a composite score after four tympanocentesis of at least 10 points. Failure occurs for those below 10 points and a score of 20 points indicates above average performance and a score of 30 points indicates superior performance. Each trainee is also assessed for three additional parameters: (1) familiarity with the procedure, (2) familiarity with instruments, and (3) manual dexterity. For these parameters the trainee is assessed as below average, pass or above average.

Performance Results
Performance regarding familiarity with the procedure, instruments and manual dexterity is presented in Table 1 for the otolaryngologists study group compared with the primary care physician study group.

Table 1

Performance on the actual tympanocentesis procedure for the otolaryngologist and physician group is shown in Table 2.

The length of time needed to complete the four tympanocentesis was procedures a mean of 4.9 minutes (range = 2.5-11.0 minutes) for otolaryngologists and a mean of 7.7 minutes (range = 3.0-14.0 minutes) for primary care physicians

Discussion

There is now an increasing recognized need for the performance of tympanocentesis in an office based setting for both otolaryngologists and properly trained/certified primary care physicians. A mannequin model has been designed to validate competency among otolaryngologists and facilitate training among primary care physicians. Training is integrated into an overall educational course organized by Outcomes Management Education Workshops (1325 S Congress Ave Suite 207, Boyton Beach, FL 33426; Phone: 561-733-6540; Fax: 561-733-4654; www.omew.com). During 1999-2000, over 3000 participants have completed tympanocentesis training. 

The AMA level three certificate awarded indicates proctor readiness for additional training among primary care providers. As such the certificate is not sufficient for a primary care physician trainee. Further instruction should be provided by a board eligible/certified otolaryngologist, preferably in the operating room suite during a session of tympanostomy tube insertions. In a typical morning if a trainee can perform the procedure on several patients to the satisfaction of the otolaryngologist then a letter could be provided to the trainee indicating competence. Independent performance of the procedure may then be followed. 

Performance of tympanocentesis in an office setting can be facilitated by use of an otomicroscope. This is not available during the mannequin training session. With regard to the necessity of utilizing the syringe evacuation method of middle ear effusion, this dexterity challenge can be overcome by attachment of a tympanocentesis needle to an appropriate collection device (e.g. Senturian trap) hooked to suction. In the non-anesthetized patient a papoose board is recommended for immobilization and a nurse assistant should be present to stabilize the head firmly and pull back on the pinnae if necessary. Sedation can be helpful. Use of Midazolam has been advocated (6) although in some communities its use mandates direct nurse observation, pulse oxymetry monitoring, and post procedure observation. An alternative approach which has been advocated that involves the oral administration of a mixture of Tylenol with codeine elixir (12 mg codeine/ 5 mL) to which Diazapam is added at a concentration of 2.5 mg/5 mL. The mixture is then administered according to the quantity of codeine at 1.2-1.3 mg codeine/ kg child which automatically accomplishes appropriate dosing of Diazapam. Pulse oxymetry monitoring is not mandated in most communities. Onset of action occurs within 15-20 minutes. Post-procedure observation is not necessary.

In conclusion, a tympanocentesis mannequin model validated and used to train > 3000 otolaryngologists, primary care physicians, physician assistants, nurse practitioners and physicians in training is now available. The mannequin has proven extremely useful as a training device in an era where the tympanocentesis procedure is undergoing a renaissance in use. The model could be considered for instruction of medical students and physicians in training, as part of their educational curriculum as well as a tool in CME accredited teaching activities for physicians in practice.

References

1. Dowell SF, Butler JC, Giebink GS, Jacobs MR, Jernigan D, Musher DM, et al. Acute otitis media: management and surveillance in an era of pneumococcal resistance - a report from the drug resistant Streptococcus pneumoniae therapeutic working group. Pediatr Infect Dis J 1999;18:1-9.
2. Giebink GS, Canafax DM, Kempthorne J. Antimicrobial treatment of acute otitis media. J Pediatr 1991;119:495-500.
3. Klein JO. Otitis media. Clin Infect Dis 1994;19:823-833.
4. Berman S. Otitis media in children. N Engl J Med 1995;332:1560-1565.
5. Pichichero ME. Acute otitis media: part I. improving diagnostic accuracy. Am Family Physician 2000;61:2051-2056.
6. Block SL. Tympanocentesis: why, when, how. Contemp Pediatr 1999;16:103-27.