Physiologic Eustachian Vinod

Misurya, MB, BS; DOMS; DLO;

Tube Inflation

MS

\s=b\ A new maneuver

(oral positive presof voluntary middle ear inflation is described. The efficacy of this new maneuver over the Valsalva maneuver was established by conducting an experiment in 50 normal volunteers and a clinical trial in 75 patients with Eustachian tube obstruction and in 25 patients with chronic serous otitis media. The lower opening pressure and higher available head of pressure, characteristic of this new maneuver, is hoped to be of definite therapeutic value in the management of the previously mentioned conditions. This maneuver has a potential for use in aviation medicine.

VALSALVA MANEUVER

sure)

(Arch Otolaryngol 101:730-732, 1975)

therapeutic importance Thevoluntary middle inflation health of

a

ear

maintaining the tympanic cleft is evident.1 The most popular of these is the time-hon¬ maneuver

of

in

a

ored Valsalva maneuver. A second mechanism of voluntary ventilation of the middle ears, first used by the Germans in the World War II, is the nasopharyngeal positive pressure ma¬ neuver.2 The other mechanisms of Eu¬ stachian tube inflation (eg, Toynbee maneuver, politzerization, and Eu¬ stachian tube catheterization) are of relatively minor importance for vol¬ untary inflation. Accepted for publication May 26, 1975. From the Department of Otolaryngology, Maharani Laxmi Bai Medical College, Jhansi, Uttar Pradesh, India. Reprints not available.

The Valsalva maneuver was first introduced in 1704 by Antonio Val¬ salva in his treatise, "Trachus De Aure Humana" (reported by Steven¬ son and Guthrie3). This maneuver consists of forceful expiration with the mouth and nose firmly closed, thus forcing the air to pass into the middle ear via the Eustachian tube. Originally, he recommended its use as a therapeutic measure for expelling the pus in cases of otitis media with a perforated tympanic membrane. Sub¬ sequently, it was employed for infla¬ tion of the middle ear in cases of ob¬ structed Eustachian tube,3 and by flyers during World War II. The mean pressures required to open the Eustachian tube are 33.7 mm Hg, 38 mm Hg, and 30 mm Hg as recorded by Chunn,4 Nordhoff (re¬ ported by Frenzel2) and Perlman,5·6 respectively. The nasopharyngeal positive pressure obtainable with the Valsalva maneuver ranged from 50 to 230

mm

Hg.2

FRENZEL MANEUVER

The Frenzel maneuver (nasopha¬ ryngeal positive pressure maneuver) consists of voluntarily closing the glottis, mouth and nose while simul¬ taneously contracting the superior pharyngeal constrictor and muscles of the floor of mouth. Unfortunately, there is relative difficulty in explain¬ ing and teaching this method. According to Chunn," the mean Eu-

stachian tube opening pressure is 6 mm Hg, in contrast to a mean open¬ ing pressure of 33 mm Hg with the Valsalva maneuver. This difference is due to active opening of the Eu¬ stachian tube and absence of naso¬ pharyngeal turgor during the Frenzel maneuver. Positive pressure can be achieved that is equal to or higher than with the Valsalva maneuver.2 TOYNBEE MANEUVER In

1853, Toynbee described

a ma¬

swallowing with a closed nose, thereby opening the Eustachian tube at ground level (reported by Politzer7). Toynbee believed that this maneuver generated a positive pres¬ sure within the middle ear cavity. Subsequently, Politzer has demon¬ strated that a negative pressure was left in the middle ear.7 This diaphasic pressure change is not great, ranging between +4 to —8 mm Hg.7 neuver

of

Since egress of air from the middle cavity has not been a great clini¬ cal problem, there appears to be little practical application of the Toynbee maneuver. One possible use would be the prevention of oxygen-absorption barotitis. ear

OTHER MECHANISMS

Since other mechanisms of Eu¬ stachian tube inflation, eg, politzerization and Eustachian tube catheterization, require an external instrument, their application as vol¬ untary methods of inflation cannot be recommended.

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METHOD

The pressure

The oral positive pressure maneuver of voluntary middle ear ventilation is accom¬ plished in the following steps.

Inflation of Oral

Cavity

The mouth is closed firmly and the oral is filled with air by inflating the cheeks as much as possible. The oral cavity is closed posteriorly by the tongue, which is relfexly uplifted and pressed against the hard palate. In this way, the oral cavity converts into a closed cavity that is filled up with pressurized air (mean pressure, 160 mm Hg).

cavity

for Middle Ear Inflation

Preparation

The palm of the hand is put the mouth while its thenar eminence is resting over one inflated cheek and the finger tips are resting over the other inflated cheek. The glottis is then closed by holding the breath and pinching the nose, thereby con¬ verting the nasopharynx into a closed cav¬ ity (only connected to the middle ear through the Eustachian tube). over

Inflation of Middle Ear

Finally, the act of swallowing synchro¬ nously with the squeezing of inflated cheeks is performed. The process of rapid and forceful manual squeezing of inflated cheeks should coincide with the late phase of the swallowing act. The main purpose is to pump the pressurized air (160 mm Hg) from the oral cavity into the nasopharynx, since in the late phase of swallowing the tongue and soft palate move down and connect the previously closed oral cavity with the nasopharynx. In this way, the oral cavity filled with pressurized air may be called a "natural Politzer bag." During the act of swallowing, there is a physiological active opening of the Eu¬ stachian tube. Therefore, the pressurized air of the nasopharynx can be forced easily into the middle ear through the Eustachian canal. In this way, the minimum pressure required for Eustachian insufflation is very much less (6 mm Hg).

EXPERIMENT A

comparative study between the

new

and the Valsalva maneuver was conducted regarding its efficacy in 50 nor¬ mal volunteers, 75 patients with Eu¬ stachian tube obstruction, and 25 patients with chronic serous otitis media. The minimum nasopharyngeal pressure required for opening the Eustachian tube was recorded in 50 normal volunteers while performing the new maneuver and the Valsalva maneuver. maneuver

connecting the

changes nose

recorded by ordinary blood the help of rub¬

were

to the

pressure instrument with

ber tubing. While the examiner's ear is connected to the ear of the subject through the diagnostic tube, the examiner watches the mercury column as he listens for the distinct sound that marks the moment when the tube is opened and the drum is forced outward. This particular pressure is the minimum Eustachian tube opening

pressure.6 CLINICAL TRIAL The oral positive pressure maneuver was tried in those patients with Eustachian tube obstruction (75) and chronic secretory otitis media (25) in whom the Valsalva ma¬ neuver was unsuccessful. The new method of voluntary Eu¬ stachian tube inflation was tried in 50 vol¬ unteers of various age and sex, and two factors were determined (Fig 1): (1) the minimum average Eustachian tube open¬ ing pressure is 6 mm Hg (ranged from 4 to 20 mm Hg), while the average maximum nasopharyngeal pressure is 160 mm Hg (ranged between 90 and 230 mm Hg); and (2) while performing the Valsalva maneu¬ ver in the same subjects, the minimum average Eustachian tube opening pressure is 40 mm Hg (8 to 72 mm Hg), and the average maximum nasopharyngeal pres¬ sure obtainable is 90 mm Hg (45 to 220 mm

Hg). Subsequently, this new maneuver successfully used in patients with

was

Eu¬ stachian tube obstruction (75) and chronic serous otitis media (25) in whom the Val¬ salva maneuver was unsuccessful.

COMMENT

The currently accepted methods of voluntary middle ear inflation—Val¬

salva and Frenzel maneuvers-have been considered. Since the remaining procedures require an external in¬ strument, their application to volun¬ tary inflation of the Eustachian tube is not recommended. The Toynbee maneuver appears to be of little prac¬ tical importance since the egress of air from the middle ear cavity has not been a great clinical problem. This new method also has several advantages as compared to the Val¬ salva maneuver. In the present series, the mean Eustachian tube opening pressure was 6 mm Hg in contrast to a high mean opening pressure with the Valsalva maneuver of 40 mm Hg. The difference in the opening pres¬ sure can be explained by two factors:

(1) this new method of voluntary in¬ flation of the Eustachian tube is asso¬ ciated with the muscular dilation of the tube, similar to that occurring during swallowing. In the Valsalva maneuver, this factor is missing8; and (2) the raised intrathoracic pressure that is seen during the Valsalva ma¬ neuver impairs the venous return from the head, resulting in the in¬ creased turgor of the nasopharyngeal tissue and congestion around the Eu¬ stachian tube lumen. This, in turn, compresses the tubai lumen. There¬ fore, its prolonged use might lead to an even higher tubai opening pres¬ sure.9 The new method can achieve positive pressure that is equal to or higher than that achieved via the Valsalva maneuver. Subsequently, in the 75 patients with Eustachian tube obstruction and the 25 patients with chronic secretory otitis media in whom the Valsalva '"

unsuccessful,

maneuver was

ful inflation

was

new maneuver.

success¬

accomplished by this

This establishes its

superiority over the Valsalva maneu¬ ver as a therapeutic measure for chronic

serous

otitis media.

Regarding the Frenzel maneuver (nasopharyngeal positive pressure method) of middle ear inflation, it

not feasible to compare it with the new method since training for the Frenzel maneuver is more tedious than the other methods because of the involuntary nature of functions nor¬ mally performed by those muscle groups that are involved in this ma¬ neuver. In addition, there is relative difficulty in explaining and teaching the Frenzel maneuver. However, this new maneuver of middle ear inflation can be explained and taught as easily as the Valsalva maneuver. The pres¬ ent method is preferable to the Fren¬ zel maneuver since its mean max¬ imum obtainable positive pressure (160 mm Hg) is higher than that of the Frenzel maneuver (150 mm Hg).2 The future prospects of this new maneuver of voluntary middle ear ventilation in aviation medicine are as follows. 1. The new method of middle ear inflation is independent of both intra¬ thoracic pressure and the phase of respiration. These features are of was

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great importance in aviation medi¬ cine.10 This

in¬

maneuver, being dependent of intrathoracic pressure, can be performed safely, with no fear of catastrophic outcome of the syn¬ new

cope. 2. This

procedure is independent of the phase of respiration. Therefore, middle ear air can be replenished with the alveolar air (concentration relatively low in oxygen and high in carbon dioxide) by the end expiratory tubai inflation. Poppen1 is optimistic in reducing the incidence of delayed

aerotitis media due to prolonged breathing of 100% oxygen (oxygen absorption barotitis), by replacing the oxygen of the middle ear with the air of alveolar composition. This end ex¬ piratory tubai inflation with the Val¬ salva maneuver is difficult, if not im¬

possible,

to

perform.

3. While performing the maneuver, it was determined that an equal or higher magnitude of positive pres¬ sure (mean pressure, 160 mm of Hg) can be achieved than with the Val¬ salva maneuver11 (mean maximum

obtainable in Valsalva method is 90 mm Hg in the present series, and 105 mm Hg in the series of Nordhoff2). This feature is of vital help as a built-in "safety valve fac¬ tor." A pilot who is afflicted with the temporary Eustachian tube obstruc¬ tion due to an upper respiratory tract infection has a much greater "head of pressure" to call on with the new ma¬ neuver.11 This added safety factor is likely to mitigate the in-flight dis¬ ability that is caused by the occur¬ rence of aerotitis media. pressure

References 1. Poppen JR: The ear in flying. Trans Am Otolaryngol Soc 31:282-291, 1941.

2. Frenzel H: Otorhinolaryngology, in German Aviation Medicine World War II. Washington

DC, US Government Printing Office, 1950, chap 2, pp 977-994.

3. Stevenson RS, Guthrie D: A History of Otolaryngology. Edinburgh, E & S Livingstone Ltd,

1949, p 20.

4. Chunn SP: A Comparison of the Efficiency of the Valsalva Maneuver and the Pharyngeal Pressure Test and the Feasibility of Teaching

Both Methods, ACAM thesis. USAF School of Aerospace Medicine, 1960. 5. Perlman HB: The Eustachian tube: Abnormal patency and normal physiologic state. Arch Otolaryngol 30:212-238, 1939. 6. Perlman HB: Quantitative tubal function. Arch Otolaryngol 38:453-465, 1943. 7. Politzer A: Diseases of the Ear. Philadelphia, Lea & Febiger, 1909. 8. Rich AR: A physiological study of the Eustachian tube and its related muscles. Bull Johns Hopkins Hosp 31:206-214, 1920.

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9.

Armstrong HC: Aerospace Medicine. BaltiWilliams & Wilkins Co, 1961, chap 11, pp

more,

162-174. 10. Duvoisin RC, Kruse F Jr, Saunders D: Convulsion syncope induced by the Valsalva maneuver in subjects exhibiting low G tolerance. Aerosp Med 33:92-96, 1962. 11. Kos CM: Effect of barometric pressure changes on hearing. Arch Otolaryngol 41:322\x=req-\ 326, 1945.

Physiologic eustachian tube inflation.

A new maneuver (oral positive pressure) of voluntary middle ear inflation is described. The efficacy of this new maneuver over the Valsalva maneuver w...
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