Your darn ears feel plugged after a viral illness such as a bad cold or a grueling air flight (or both) where you’d swear the pilot was having a jolly good time doing a few stunts while landing the plane, as the copilot with the sick sense of humor intentionally messed with the cabin pressure controls because he was bored out of his mind.
You clear or “pop” your ears by blowing your nose vigorously or by doing a Toynbee Maneuver, where you exhale forcefully from your nose against tightly-closed nostrils squeezed with your fingers. You feel a “pop” and the ear fullness and hearing improves. You do this repeatedly for the next few days to clear your ears.
When this occurred to you in times past, the ear problem eventually resolved and you returned to your happy state of being. Yet after one particular flight or after a bout with a really nasty virus, you find you’re still popping your ears. You do this over and over again…ad infinitum…but disappointedly it doesn’t “stick”—your hearing doesn’t remain permanently improved. So what goes?
The problem could be the eustachian tubes. As the prior post explains (The Eustachian Tube Part 1: Ear Popping and Eustachian Tube Dysfunction) air is forced into your middle ear (ME) from your eustachian tube (ET) to equalize ME pressure. Things that affect the eustachian tube, causing it to collapse and close such as swelling of the tube from a cold or the pressure difference from a change in altitude while travelling, will cause negative ME pressure. Blowing air into the ET and into the ME helps to restore pressure back to normal and thus improve hearing and resolution of the ear plugging or fullness.
After a while (and it can take months…yes, months!) the ET recovers and the ME pressure remains constantly the same as atmospheric pressure--the normal pressure of the environment outside the ear. However, some folks continue to “pop” their ears with the Toynbee maneuver, despite the return of the ET and ME to its normal state of being. They still feel the need to clear the ears, noting a brief improvement in hearing.
These folks create a temporary condition of positive middle ear pressure, or pressure that is greater that the outside atmospheric pressure. This is a relative term and this condition and, like negative ME pressure, is not normal. Both problems cause symptoms. Both can cause alterations in the shape and sound conducting qualities of the ear drum or tympanic membrane (abbreviated TM).
Another problem that leaves one with a sense of ear pressure or ear fullness arises from the cochlea. After a viral illness or a session of loud noise exposure such as a rock concert or the deafening roar of a crazy Chinese New Year’s celebration where scores of people light whole packs of fire crackers all at once, one often comes away with plugged ears and muffled hearing, and perhaps a bit of ear-ringing to boot. Popping the ears is a natural thing to do, but the effect is not related to restoring normal ME pressure, but temporarily changing the TM shape and thus the hearing dynamics which can improve hearing briefly. The ME pressure was never changed during the noise exposure. On the contrary, there is a loss of hearing due to injury to the inner ear--the snail-shaped organ called the cochlea--caused by loud noise or a viral infection of the ear. In this case, it is the cochlear hearing loss itself that causes the plugged, full or muffled sensation (we call this phenomenon aural fullness). As the cochlea recovers (hopefully), hearing improves along with the sensation of fullness. However, in some cases the hearing does not return to normal and that sense of aural fullness persists. Popping the ears in this case temporarily increases the pressure in the ME where it is abnormally greater than atmospheric pressure. This causes the TM to bulge out and likely changes its vibratory character and temporarily improves hearing. However, since the ET is functioning normally, the ME pressure quickly equalizes and returns to normal and that sensation of improved hearing goes away.
The problem is a state of positive pressure cannot be maintained forever, nor should it. The process of the ear returning back to its normal state may take a long while, such that the improvements are not noticeable, due to the rather long recovery. And once the ME and ET do return back to their baseline, or if cochlear hearing recovers, there could be a habitual problem of repeated ear-popping long after the necessity for this has passed. Only now, the person feels improvement above his/her baseline hearing. In other words, the Toynbee maneuver causes a noticeable but hearing improvement that is temporarily better than that person’s “normal” (or baseline) state of hearing. As such, he/she repeatedly pops the ears to “clear” them.
This phenomenon of aural fullness can also occur with more gradual permanent cochlear hearing loss, where the ear fullness is felt chronically without an antecedent cold or travel through altitudes. The hearing loss itself is the cause of aural fullness and not the ME or ET.
Despite normal ET function and ME pressure, they still notice brief improvement in hearing. This is true in some respects. As they blow air through a normal ET and ME, the middle ear pressure increases. This increases air density in the ME, which in turn causes the TM to bulge out. This change in TM shape can improve hearing but is short lived. Also sound conducts better through denser air, as there are more molecules to pass sound waves from one to another (see Hearing and the Physics of Sound Mechanics). However, this persistent positive pressure cannot and should not persist.
If the ENT exam and tympanograms (device that measures middle ear pressure) is normal, I try to convince these patients to avoid popping their ears, since the need to do so has passed. If instead they are popping their ears by manipulating their jaw (i.e., popping their TMJ, I strongly instruct them to avoid doing this, since they aren’t opening their ETs but creating another problem (see the post Ear Popping and Crackling Noises),
Patients often feel in these situations that if the pressure could just release from the ear by popping a whole in the TM or placement of a ventilation tube, all will be well. On the contrary, a tube would simple equalize ME pressure; air crossing to and from the tube will naturally keep the ME pressure normal at all times. And when the patient does a Toynbee maneuver and blows air up into his nose, there will be little to no effect on the TM since the air forced into the ET and into the ME will simply exit from the tube. They’re literally blowing it out of their ear and will notice no change in hearing.
On the flip side, there are no means to keep the ME pressure greater than normal; this defeats the purpose of the ET. You don’t want to have continuous positive pressure, since this will cause the TM to bulge and potentially pop a hole into it, and resulting in no benefit. I’ve had some people ask about plugging the ET, but this creates negative ME pressure, leading to other things such as above, leading to more hearing loss and ear pain.
So, in summary:
A Toynbee maneuver increases middle ear pressure and is helpful while having an actual eustachian tube problem (which causes negative middle ear pressure) where pressure is returned to normal atmospheric pressure. However, this can become a habitual process once the middle ear and eustachian tube return to normal function, and patients continue doing the maneuver unnecessarily. Positive pressure is created instead (which is not natural) and will temporarily improve hearing due to alteration of TM and thus changing the hearing dynamics briefly. When the ET does recover, this is no longer necessary and one should avoid doing this maneuver unless flying or travelling through altitudes.
So do us all a favor and stop blowing air into your ears. We wouldn't want your brain to explode or other such unpleasant mishaps to befall you.
©Randall S. Fong, M.D.