Anesth Analg 2002;94:467-469
© 2002 International Anesthesia Research Society
GENERAL ARTICLES
The Modified Nasal Trumpet Maneuver
Charles Beattie, PhD, MD
Department of Anesthesiology, Vanderbilt University, Nashville, Tennessee
Address correspondence and reprint requests to Charles Beattie, PhD, MD, Department of Anesthesiology, Vanderbilt University Medical Center, 1313 21st Ave. S, Room 504 Oxford House, Nashville, TN 37232-4125. Address e-mail to chas.beattie{at}mcmail.vanderbilt.edu
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Abstract
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The last decade has witnessed a proliferation of devices or methods that facilitate intubation in difficult circumstances, maintain ventilation, or which do both. These all require properly functioning and specially designed apparatus, the use of which requires variable degrees of expertise.
This technical communication describes the authors experience with a simple technique that uses virtually universally available materialsa nasal trumpet (airway) and an endotracheal tube (ETT) connectorto rescue patients in the cannot-ventilate/cannot-intubate scenario. The methodology is straightforward, ventilation is usually immediate, stomach contents can be evacuated while ventilation proceeds, and it does not require mouth opening. Moreover, while ventilation and oxygenation is continuing, a fiber-optic intubation can proceed without interference.
IMPLICATIONS: A simple technique is proposed that can be used to rescue patients who are in a condition of cannot intubate/cannot ventilate. The described maneuver may save patients from requiring a surgical airway.
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Methods
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The author was consulted for 35 adult patients over 15 yr and in two major academic institutional settings who were in a condition of cannot ventilate/cannot intubate. Seventeen had received sedation and long or intermediate acting, nondepolarizing muscle relaxants and were not making respiratory efforts. Eighteen had received succinylcholine along with sedatives, opiates, or both. Seventeen of these patients were making inspiratory efforts; 12 of these were seriously or completely obstructed, and ventilation was ineffectual. Many were elective surgical patients, and the unanticipated difficult airway was discovered at induction. Surgeons were on site in most instances, and several were in various stages of preparing to initiate a surgical airway. All patients had undergone multiple attempts at intubation from different anesthesia personnel who used different blades. Oral and nasal airways had been or were being used. Different stylets and tube sizes had been attempted. In most cases, blood and secretions were copious. Two-person mask ventilation was being attempted in 12 cases.
The materials used consisted of a 30 or 32 French soft nasal airway (trumpet) and a 7.5- or 8-mm ETT connector. The ETT connector was inserted into the flared or proximal end of the nasal airway, i.e., the modified nasal trumpet (MNT) (Fig. 1). Some airways were further modified by a cut fenestration, or "Murphy eye," of the nasal trumpet on the side opposite the beveled opening with scissors.

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Figure 1. The Modified Nasal Trumpet (MNT). Ordinary nasal airway with an endotracheal tube (ETT) connector wedged into the flared end. Also shown is an optional "Murphy eye," a fenestration cut (with scissors) into the distal end opposite and slightly proximal to the bevel.
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Establishing Ventilation
Ventilation attempts in progress were suspended. A lubricated MNT was inserted into a patients nostril and attached to the circle system. Care was taken to medially orient the beveled opening if the MNT was not fenestrated. All oral instrumentation was removed. The other nostril was occluded, and the mouth and lips were shut tightly (Fig. 2). Positive pressure was applied to the bag. If the patient was making respiratory efforts, the bag squeeze was synchronized with the inspiratory phase (assist). The bag was squeezed firmly but slowly. Time was allowed for exhalation.

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Figure 2. Patient being ventilated (control or assist) through the modified nasal trumpet (MNT), which has been placed in the right nostril. Note mouth and lips held firmly shut and other naris occluded with thumb.
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If the initial squeeze did not obviously inflate the lungs, the MNT was pulled out 12 cm, and bag squeeze was repeated. If not successful, the MNT was moved to the opposite nostril. If still not successful, the degree of muscle relaxation was assessed. If the muscle relaxant had dissipated, the patient was reparalyzed with succinylcholine. If paralysis did not lead to the ability to ventilate, a surgical airway was indicated.
Intubation
With ventilation and oxygenation in progress via the MNT, nasal fiber-optic intubation proceeded through the opposite nostril (Fig. 3). The ETT was occluded during its insertion through the nose to prevent leakage. With the fiberscope passed through the ETT, the annular leak was overcome with increased flows through the MNT. The ongoing ventilation was helpful as the airway was opened during positive pressure. The scope was advanced through the cords; the ETT was advanced into the trachea, and the circle system switched to the ETT from the MNT.

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Figure 3. As ventilation proceeds through the modified nasal trumpet (MNT), the other nostril has received a partially inserted endotracheal tube (ETT) through which is passed a fiber-optic scope. When the ETT is advanced into the trachea, the circle system is transferred to the tube.
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Results
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Patients making some respiratory efforts (almost completely ineffectual) were assisted and this maneuver increased their oxygen saturation. Four required changing the MNT to the other nostril, which was effective.
Of the patients not making respiratory effort, 11 were immediately ventilated with positive pressure through the MNT, 2 required slight adjustment (pull out of 12 cm), 3 required changing the MNT to the other nostril, and 2 required reparalysis with succinylcholine. Presumably laryngospasm or active straining prevented inflation of the lungs.
All patients were successfully ventilated; none required a surgical airway. Since preparing a fenestration on the side opposite the beveled trumpet opening, no patient has required a change in the insertion nostril.
Five patients had an obviously distended abdomen before insertion of the MNT. While ventilation proceeded, a nasogastric tube was placed through the unused nostril and into the stomach, with complete evacuation of the contents. A sufficient seal could be maintained by gently squeezing the nasogastric tube nostril during passage to permit positive-pressure ventilation via the MNT. Fiber-optic intubation was successful in all cases where it was attempted.
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Discussion
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Nasal trumpets are ubiquitous. Their contemporary use is commonly limited to the relief of upper-airway obstruction in two circumstances: 1) after extubation of the trachea in a spontaneously breathing patient, or 2) during mask ventilation when an oral airway (and jaw lift) has failed to produce an acceptable airway. It has not been previously reported that a standard, single-lumen nasopharyngeal airway could be used effectively to deliver positive-pressure ventilation as a rescue device in the cannot-ventilate/cannot-intubate scenario.
McIntyre (1) reviewed the history of the nasopharyngeal airway in 1996. Nasopharyngeal tubes, mostly of double design, were used extensively in the early 1900s, usually for delivery of a volatile anesthetic by insufflation (24). With most patients undergoing endotracheal intubation or mask ventilation, and with the disappearance of insufflation to administer inhaled anesthetics, the double-nasal tube design was used little.
Almost 60 yr later, in an effort to develop an acceptable alternative to endotracheal intubation, Elam et al. (5) and Weisman et al. (6,7) improved some features of the dual-tube binasal system and used it in a wide variety of surgical procedures under general anesthesia, including some requiring controlled ventilation. They studied 1205 patients in two reports, including 27 successful resuscitations. To maintain the airway for the time required to perform elective surgeries, they used an elastic band around the head and chin to hold the mouth closed. There were no episodes of gastric distension or aspiration.
Simplicity, availability, and the minimal training requirement characterize the MNT maneuver for use in emergency situations. The mating of the ETT connector to the nasal trumpet can occur quickly. It is possible for the nasal trumpet beveled opening to become imbedded in, or to abut, pharyngeal tissue. Changing the insertion nostril is a common early corrective action. Further modification of the device by cutting a "Murphy eye" near the distal end has reduced the need to change nostrils.
Because it is a supraglottic technique, the MNT maneuver requires relaxed or open cords. Initial inability to ventilate has been corrected by the administration of a muscle relaxant, but one must be confident that such inability to ventilate is, in fact, a supraglottic problem. The technique is not suitable for a patient with occluded or compressed nasal passages.
Gastric distention, regurgitation, or aspiration has not occurred using the MNT maneuver. If desired, a nasogastric tube can be passed down the unused nostril while ventilation proceeds. The ability to ventilate continuously while performing the fiber-optic intubation is another valuable feature of the technique. This method is an attractive option for elective, asleep, and fiber-optic assisted intubation as well, eliminating the need for special masks. Figure 4 illustrates the relationship of an inserted MNT to anatomical structures of the airway. It suggests why positive pressure delivered expressly into the perilaryngeal opening (like the laryngeal mask airway) may stent open the airway during inspiration.

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Figure 4. This schematic shows the presumed position of a properly sized and inserted modified nasal trumpet (MNT). When positive pressure is delivered through the device, the periglottic space is distended, tending to open the larynx, thus facilitating the pulmonary exchange of air.
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The MNT maneuver can be a valuable addition to our airway armament for the following reasons: (a) mask fit is eliminated as a source of inadequate ventilation, (b) mouth opening and neck manipulation are not required, c) the technique requires minimal experience, skill, and equipment, and d) the technique succeeds in establishing an airway after other conventional methods have failed.
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References
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McIntyre JWR. Oropharyngeal and nasopharyngeal airways. I (18801995). Can J Anaesth 1996; 43: 62935.[Web of Science][Medline]
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Connell K. A new ether-vaporizer: a preliminary report on the technic of intrapharyngeal insufflation anesthesia. JAMA 1913; 60: 8924.[Abstract/Free Full Text]
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Rockey AE. Anesthesia in war surgery: drop-ether pharyngeal anesthesia in plastic facial surgeryread by proxy during the Fourth Annual Meeting of the Interstate Association of Anesthetists with the Indiana State Medical Association. Hotel Claypool, Indianapolis, IN, September 2527, 1918. Am J Surg Anesth Suppl 1919; 33: 89.
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Gwathmey JT. Anesthesia. New York: The Macmillan Company 1924:157,1601.
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Elam JO, Titel JH, Feingold A, et al. Simplified airway management during anesthesia or resuscitation: a binasal pharyngeal system. Anesth Analg 1969; 48: 30716.[Free Full Text]
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Weisman H, Weis TW, Elam JO, et al. Use of double nasopharyngeal airways in anesthesia. Anesth Analg 1969; 48: 35661.[Free Full Text]
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Weisman H, Bauer RO, Huddy RA, et al. An improved binasopharyngeal airway system for anesthesia. Anesth Analg 1972; 51: 1113.[Free Full Text]
Accepted for publication October 9, 2001.
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