CHAPTER SIX
Test troubleshooting
58
Test troubleshooting
6
Test troubleshooting
6.1
OAE test problems
The most frequent cause of unsuccessful OAE recordings is failure to fit the
probe correctly, so that it is deep enough in the ear canal. The presence of
fluid and debris in the ear canal or middle ear will also inhibit recordings.
If a pass result is not obtained, remove the probe and inspect the probe tip.
Discard the tip if it has collected debris or moisture. Also check that the
probe coupler tubes are clear and replace these if a blockage is noticed.
Then refit the probe and try again. Problems of debris and middle ear
fluid occur mostly in babies younger than 6 hours and are often cleared
by feeding or turning the baby. If there is no success during the first OAE
testing attempts, a second OAE testing session usually brings success
when the ear has had time to clear.
Babies are best tested when they are sleeping or sleepy and successful
OAE recordings are most often made one hour after a feed. The baby may
settle down more easily if swaddled. Babies older than one month may be
too active to test. When testing a child it can help to entertain them during
the test, so they don’t become too restless. Try to keep the probe cable out
of their reach; using the probe cable clip may help. Instruct adults to be still
and remain quiet.
Noises from the patient may not prevent successful recording, but will
increase the test time. Constant environmental background noise, for
example from air conditioning or machinery, may prevent a successful test.
Testing should only be conducted in rooms where the noise level recording
on the Otoport is mainly below the noise reject level when the probe is not
fitted in the ear. Some intermittent noise can be tolerated, but constant
high noise will inhibit successful recordings.